This document provides an overview of renal physiology:
- The kidney removes waste, regulates fluid and electrolytes through the nephron, which filters blood and reabsorbs necessary components.
- Filtration occurs in the glomerulus and reabsorption everywhere else along the nephron. Tight control of sodium is central to water reabsorption.
- The loop of Henle and countercurrent exchange allow the medulla to concentrate urine up to 1,200 mOsm/kg, while the distal convoluted tubule and collecting duct reabsorb remaining sodium and water under aldosterone and ADH control.
The document summarizes the histology of the kidney. It describes the major structures of the kidney including the cortex, medulla, nephrons, renal corpuscles, glomerular filtration, renal tubules, and collecting system. It explains that the kidney filters blood to produce urine using nephrons as the functional unit, which contain a renal corpuscle for filtration and renal tubules for reabsorption and secretion.
Renal blood flow (The Guyton and Hall physiology)Maryam Fida
In an average 70-kilogram man, the combined blood flow through both kidneys is about 1100 ml/min, or about 22 per cent of the cardiac output. Two kidneys makes about 0.4 % of total body weight but receive very high blood flow as compared with other body organ. The purpose of additional blood flow is to supply sufficient plasma for high rates of GF which is essential for regulating body fluid volumes & solute concentrations.
Characteristics of the renal blood flow:
1, High blood flow. 1100 ml/min, or 22 percent of the cardiac output. 94% to the cortex.
2, Two capillary beds
High hydrostatic pressure in glomerular capillary (about 60 mmHg) and low hydrostatic pressure in peritubular capillaries (about 13 mmHg)
Blood flow to renal medulla is supplied by vasa recta.
Blood flow in vasa recta of medulla is very low as compared to blood flow in cortex.
Blood flow in renal medulla is 1-2 % of total renal blood flow.
Vasa recta are important to form concentrated urine.
Applied aspects of Kidney and RFT by Dr. MP.pptxPandian M
This document provides an overview of common renal disorders, including their pathophysiology, symptoms, and diagnostic tests. It discusses common urinary symptoms like polyuria, nocturia, dysuria, incontinence, and enuresis. It also covers renal failure, differentiating between acute and chronic renal failure. Nephrotic syndrome and its associated features are explained. Classification and mechanisms of action of diuretic drugs are outlined. Various renal function tests are described, including analysis of urine and blood, clearance tests using substances like inulin to measure glomerular filtration rate, and renal imaging techniques.
The document discusses the structure and function of the gastrointestinal tract, including the layers of the GI wall, innervation by the enteric and autonomic nervous systems, and hormonal control of GI functions. It covers topics like the roles of motility, digestion, secretion and absorption in the GI system. Key hormones that control GI processes like gastric acid secretion, pancreatic enzyme release and gallbladder contraction are also explained.
There are four major types of neuroglial cells in the central nervous system: astrocytes, ependymal cells, microglial cells, and oligodendrocytes. Astrocytes regulate the flow of ions and molecules to and from neurons. Ependymal cells line the brain ventricles and spinal cord canal and produce cerebrospinal fluid. Microglial cells support neurons by phagocytizing dead cells and debris. Oligodendrocytes insulate axons with myelin to speed signal transmission between neurons.
This document discusses renal physiology, including renal blood flow, oxygen consumption, regulation of blood flow, glomerular filtration, and factors affecting glomerular filtration rate (GFR). Some key points:
- Renal blood flow is approximately 1/4 of cardiac output, or 1200 ml/min. Blood flow to the cortex is higher than to the medulla.
- Glomerular filtration is determined by the net filtration pressure and filtration coefficient. Forces increasing filtration are glomerular hydrostatic pressure and oncotic pressure in Bowman's space. Forces decreasing filtration are plasma oncotic pressure and hydrostatic pressure in Bowman's space.
- GFR is regulated through autoregulation mechanisms like tub
This document contains a question bank for a physiology exam covering topics in biophysics and biochemistry of cells, blood, the cardiovascular system, the central nervous system, comparative physiology, and the endocrine system. It includes over 100 short answer and essay questions on these topics, some with suggested point values or word counts for the answers.
The document discusses the functions of the juxtaglomerular apparatus and hormonal control in the urinary system. It describes the juxtaglomerular apparatus as a specialized structure located where the distal tubule contacts the renal corpuscle. It regulates renal functions through the renin-angiotensin-aldosterone system and vasopressin response to osmolarity levels which control water retention and excretion. These systems work together to maintain fluid and electrolyte balance.
The document summarizes the histology of the kidney. It describes the major structures of the kidney including the cortex, medulla, nephrons, renal corpuscles, glomerular filtration, renal tubules, and collecting system. It explains that the kidney filters blood to produce urine using nephrons as the functional unit, which contain a renal corpuscle for filtration and renal tubules for reabsorption and secretion.
Renal blood flow (The Guyton and Hall physiology)Maryam Fida
In an average 70-kilogram man, the combined blood flow through both kidneys is about 1100 ml/min, or about 22 per cent of the cardiac output. Two kidneys makes about 0.4 % of total body weight but receive very high blood flow as compared with other body organ. The purpose of additional blood flow is to supply sufficient plasma for high rates of GF which is essential for regulating body fluid volumes & solute concentrations.
Characteristics of the renal blood flow:
1, High blood flow. 1100 ml/min, or 22 percent of the cardiac output. 94% to the cortex.
2, Two capillary beds
High hydrostatic pressure in glomerular capillary (about 60 mmHg) and low hydrostatic pressure in peritubular capillaries (about 13 mmHg)
Blood flow to renal medulla is supplied by vasa recta.
Blood flow in vasa recta of medulla is very low as compared to blood flow in cortex.
Blood flow in renal medulla is 1-2 % of total renal blood flow.
Vasa recta are important to form concentrated urine.
Applied aspects of Kidney and RFT by Dr. MP.pptxPandian M
This document provides an overview of common renal disorders, including their pathophysiology, symptoms, and diagnostic tests. It discusses common urinary symptoms like polyuria, nocturia, dysuria, incontinence, and enuresis. It also covers renal failure, differentiating between acute and chronic renal failure. Nephrotic syndrome and its associated features are explained. Classification and mechanisms of action of diuretic drugs are outlined. Various renal function tests are described, including analysis of urine and blood, clearance tests using substances like inulin to measure glomerular filtration rate, and renal imaging techniques.
The document discusses the structure and function of the gastrointestinal tract, including the layers of the GI wall, innervation by the enteric and autonomic nervous systems, and hormonal control of GI functions. It covers topics like the roles of motility, digestion, secretion and absorption in the GI system. Key hormones that control GI processes like gastric acid secretion, pancreatic enzyme release and gallbladder contraction are also explained.
There are four major types of neuroglial cells in the central nervous system: astrocytes, ependymal cells, microglial cells, and oligodendrocytes. Astrocytes regulate the flow of ions and molecules to and from neurons. Ependymal cells line the brain ventricles and spinal cord canal and produce cerebrospinal fluid. Microglial cells support neurons by phagocytizing dead cells and debris. Oligodendrocytes insulate axons with myelin to speed signal transmission between neurons.
This document discusses renal physiology, including renal blood flow, oxygen consumption, regulation of blood flow, glomerular filtration, and factors affecting glomerular filtration rate (GFR). Some key points:
- Renal blood flow is approximately 1/4 of cardiac output, or 1200 ml/min. Blood flow to the cortex is higher than to the medulla.
- Glomerular filtration is determined by the net filtration pressure and filtration coefficient. Forces increasing filtration are glomerular hydrostatic pressure and oncotic pressure in Bowman's space. Forces decreasing filtration are plasma oncotic pressure and hydrostatic pressure in Bowman's space.
- GFR is regulated through autoregulation mechanisms like tub
This document contains a question bank for a physiology exam covering topics in biophysics and biochemistry of cells, blood, the cardiovascular system, the central nervous system, comparative physiology, and the endocrine system. It includes over 100 short answer and essay questions on these topics, some with suggested point values or word counts for the answers.
The document discusses the functions of the juxtaglomerular apparatus and hormonal control in the urinary system. It describes the juxtaglomerular apparatus as a specialized structure located where the distal tubule contacts the renal corpuscle. It regulates renal functions through the renin-angiotensin-aldosterone system and vasopressin response to osmolarity levels which control water retention and excretion. These systems work together to maintain fluid and electrolyte balance.
The document summarizes urine formation and micturition. Urine is formed through glomerular filtration in the kidneys where water and small molecules pass through the glomerular membrane into the filtrate. Most of the filtrate is reabsorbed in the renal tubules, with less than 1% excreted as urine. Micturition is the process of emptying the bladder through contraction of the detrusor muscle and relaxation of the internal urethral sphincter.
The basal ganglia consist of several structures including the caudate nucleus, putamen, globus pallidus, substantia nigra, and subthalamic nucleus. They are located within the cerebral hemispheres and are involved in motor control and cognition. Two main circuits exist - the putamen circuit for executing movements and the caudate circuit for cognitive motor control. Diseases that impact the basal ganglia like Parkinson's and Huntington's result from dysfunction of neurotransmitter pathways and can cause both hyperkinetic and hypokinetic movement disorders. Common treatments involve replacing dopamine or modifying basal ganglia circuitry.
Movements in the GIT( the guyton and hall physiology)Maryam Fida
movements in GIT
1. Propulsive Movements -------- Peristalsis
2. Mixing Movements
Moves food forward along GIT at an appropriate rate for digestion and absorption
A contractile ring appears around the gut and then moves forward
Stimulation at any point in the gut can cause a contractile ring to appear in the circular muscle, and this ring then spreads along the gut tube
Directional movement toward Anus
Can occur in either direction but normally occurs towards anus
Requires active myenteric plexus
Stimulus for intestinal peristalsis
Distention of the gut
Irritation
Parasympathetic nervous signals
Peristalsis is absent:
Congenital absence of myenteric plexus
Atropine (paralyzes cholinergic nerve endings)
Peristalsis also occurs in
Bile ducts
Glandular ducts
Ureters
Many other smooth muscle tubes of the body
Law of the Gut or Peristaltic Reflex or Myenteric reflex:
Peristaltic reflex plus anal direction of movement of peristalsis is called "law of the gut”
Contractile ring normally begins on orad side of distended segment
The gut sometimes relaxes several centimeters downstream toward the anus, called "receptive relaxation," thus allowing food to be propelled easily anally
The document discusses the physiology of the kidney. It provides an overview of renal functions such as regulating water, electrolyte and acid-base balance, and excreting waste products. It describes the structure of the kidney including nephrons, glomeruli and tubules. It discusses glomerular filtration, the processes of filtration, reabsorption and secretion, and how clearance is used to measure glomerular filtration rate and renal blood flow.
The document discusses the formation of concentrated urine through a countercurrent system and urea recycling in the kidneys. It explains that concentrated urine is formed through (1) high levels of ADH hormone and (2) development and maintenance of a hyperosmotic renal medullary interstitium. This gradient is established through a countercurrent system using the loop of Henle and vasa recta blood vessels, as well as urea recycling back into the medulla. Sodium and other solutes are deposited in the medulla through these mechanisms to draw water out of the urine as it passes through the kidneys, resulting in highly concentrated urine.
The cerebral cortex is a thin sheet of neural tissue that surrounds the cerebrum. It plays a key role in functions like memory, awareness, language, and consciousness. It is divided into two hemispheres and four lobes. It has six layers and is made up of grey matter on the inside and white matter on the outside. The cortex contains several functional areas including sensory, motor, and associated areas. The sensory areas process somatosensation, vision, hearing, smell, and taste. The motor areas control voluntary movement. The associated areas integrate information for functions like cognition and language.
1. Renal blood flow is tightly regulated to maintain a constant rate of around 1200 mL/min despite wide changes in blood pressure, through mechanisms like autoregulation and tubuloglomerular feedback.
2. The kidneys receive a high blood flow of around 20-30% of cardiac output despite their small size, and oxygen consumption in the kidneys is very high, second only to the heart.
3. Blood enters the kidneys through the renal artery and is distributed through a branching network of arteries before entering the glomerular capillaries and surrounding the nephron tubules, with the renal veins collecting the blood and returning it to circulation.
Tubular reabsorption (The Guyton and Hall physiology)Maryam Fida
It is the second step of urine formation.
It is defined as;
“ The process by which water and other substances are transported by renal tubules back to blood is called Tubular Reabsorption”.
Tubular reabsorption is highly selective.
Some substances like glucose and amino acids are completely absorbed from tubules. So, the urinary excretion is zero.
Ions such as Na+, Cl-, HCO3- are highly absorbed but rate of absorption and excretion varies, according to body needs.
Materials Not Reabsorbed
Nitrogenous waste products
Urea
Uric acid
Creatinine
Excess water
The renal system consists of the kidneys and urinary bladder. The kidneys play a vital role in maintaining fluid balance and composition in the body, regulating the internal environment. The kidneys are composed of nephrons which filter blood, reabsorbing necessary substances and secreting waste products to produce urine. Urine is stored in the bladder and emptied during micturition.
The cerebellum plays an important role in motor control and coordination. It receives input from various sources, including the spinal cord, brainstem, and cerebral cortex. This input is processed within the cerebellar cortex and nuclei. The cerebellum then sends output to motor areas of the brainstem and cerebral cortex to coordinate movement, balance, and posture. It acts as a comparator, receiving feedback on actual movements and comparing them to intended movements, in order to calibrate motor output and prevent overshooting during voluntary motor acts such as walking and running. Damage to the cerebellum can cause ataxia or lack of coordination.
The document discusses the central nervous system. It begins by describing the general design of the nervous system, noting that the CNS contains over 100 billion neurons and synapses allow signals to pass in a forward direction. It then discusses the divisions of the nervous system, describing the central nervous system as consisting of the brain and spinal cord. The spinal cord functions to transmit sensory and motor signals and mediate reflexes. The document goes on to describe the structure and tracts of the spinal cord, as well as the sensory and motor parts of the nervous system. It discusses the different levels of function in the CNS including the spinal cord, lower brain, and higher brain levels. The document concludes by describing CNS synapses and various types
Nephron (The Guyton and Hall physiology)Maryam Fida
Structural and Functional unit of kidney is called nephron.
There are about 1.3 million nephron in each kidney.
New nephrons can not be regenerated by kidneys.
Functioning nephrons decrease about 10 % every 10 years at the age of 40.
At the age of 80, there are 40 % of functioning nephrons as compared to 40 yrs.
It is formed by two parts.
1. GLOMERULUS
2. BOWMAN’S CAPSULE
1- Glomerulus:
It consists of tuft of glomerular capillaries.
There is anastomosing & branching network of glomerular capillaries.
Glomerular capillaries have high hydrostatic pressure (nearly 60 mm Hg) as compared with other capillaries.
Glomerulus is surrounded by a membranous cover called Bowman’s capsule.
Each glomerulus is about 0.2 mm in diameter.
Glomerulus and Bowman’s capsule together constitute renal corpuscle.
Each renal tubule is divided into various part as they have different functions.
i- Proximal convulated tubule.
It is continuation of Bowman’s capsule.
ii- Loop of Henle. It is continuation of prox. conv. tubule.
* Loop of Henle has three parts.
a- descending limb,
b- u turn or bend in medulla and
c- ascending limb.
Ascending limb has initial thin segment followed by thick segment.
At the end of thick ascending limb, there is short segment called macula densa, which plays important role in controlling functions of nephron.
The central nervous system (CNS) and peripheral nervous system (PNS) have 3 general functions: collect information through receptors, process and evaluate information, and respond to information. Neurons communicate via action potential propagation and neurotransmitter release. The sensory division has somatic and visceral components, with visceral sensory being part of the autonomic nervous system. The motor division has somatic and autonomic components. Nervous tissue in the CNS contains glial cells and neurons. During development, the neural plate forms the neural groove and neural tube from ectoderm. The CNS contains around 100 billion neurons organized into the brain and spinal cord.
The document provides an overview of kidney anatomy and physiology. It discusses:
1. The basic functions and structures of the kidney, including filtration, homeostasis, and hormone production.
2. The anatomy of the kidney, including locations of the cortex, medulla, renal pyramids and other structures.
3. The nephron as the functional unit of the kidney, describing its role in filtration, reabsorption, secretion and other processes.
4. Key physiological concepts like the countercurrent multiplier mechanism and regulation of electrolytes and acid-base balance.
Kidney (STRUCTURE AND FUNCTIONS) (: The Guyton and Hall physiology)Maryam Fida
STRUCTURE AND FUNCTIONS OF KIDNEY
There are two kidneys in body , Rt & Lt, lying on post abdominal wall, outside peritoneal cavity.
There weight is aprx. 150 Gm and size is clenched fist.
On medial side, there is a region called hilum through which pass blood & lymphatic vessels, nerve fibers and ureterKidney is surrounded by a protective fibrous capsule.
Each kidney has two major zones, outer thick known as cortex and part known as medulla.
Medulla is divided into multiple cone shaped tissue masses called renal pyramid.
The base of pyramid begins at junction of cortex & medulla and terminates in papilla which projects into space of renal pelvis.
Renal pelvis is funnel shaped continuation of upper end of ureter.
1- Excretion of metabolic waste products such as urea, creatinine, uric acid, Bilirubin, hormones & drugs.
2-. ELIMINATE HARMFUL FOREIGN COMPOUNDS.
Such as toxins, drugs, heavy metals, pesticides.
3- Regulation of water & electrolyte balance to maintain normal homeostasis of body by re-absorption and adjustment of rate of excretion of various substances.
4- Regulation of Arterial Pressure.
*Long term regulation by excreting variable amounts of water and sodium
and
*short term by secreting vaso-active substance (renin).
Important questions of physiology for 1st year mbbs students by dr. mudassar ...Dr. Mudassar Ali Roomi
This document provides an outline of important topics in cardiac physiology, including:
1) The phases of the cardiac cycle, including isovolumic contraction and relaxation.
2) The phases of the action potential in ventricular and SA nodal fibers and what a pre-potential is.
3) The components of the cardiac conduction system and timings of impulse conduction, including what AV nodal delay is and its importance.
4) Features of the normal ECG waves, segments and intervals.
This document discusses glomerular filtration and the glomerular filtration rate (GFR). It defines glomerular filtration as the process where plasma filters through the glomerular capillaries into Bowman's capsule, the first step in urine formation. The GFR is the rate at which plasma is filtered and is an important measurement of kidney function. Normal GFR is about 125 mL/min. The kidneys filter the plasma around 60 times per day. Renal blood flow to the kidneys is high at around 1200 mL/min and is regulated by the afferent and efferent arterioles. Glomerular filtration is governed by the filtration coefficient and Starling forces of hydrostatic and oncotic pressures
This document summarizes the anatomy and physiology of the nephron, specifically the collecting tubules and juxtaglomerular apparatus. The collecting tubule is the final segment of the nephron before entering the collecting duct system. It can be divided into the cortical and medullary collecting tubules. The cortical collecting tubule reabsorbs sodium, potassium, and water. The medullary collecting tubule is responsible for acidification of urine and is permeable to water and urea. The juxtaglomerular apparatus is formed by modified cells in the afferent arteriole and macula densa. It detects changes in chloride concentration and blood pressure, triggering the release of renin and regulating the
The document provides an overview of the nervous system, including its general functions of sensation, integration, and motor response. It describes the main cell types of the nervous system as neurons, which perform the major functions, and neuroglia, which play a supporting role. Neurons are classified as afferent, interneurons, or efferent. The central nervous system consists of the brain and spinal cord, which contain gray matter for signal processing and white matter for tract formation. The peripheral nervous system connects to the central nervous system via afferent and efferent tracts in the spinal cord.
The document provides information on the historical background and structure of neurons. It discusses how Purkinje, Golgi, and Cajal contributed to understanding neurons through their research using early microscopes. Their work led to the Neuron Doctrine which established that the neuron is the fundamental unit of the nervous system. The document then describes the main structures of the neuron in detail, including the cell body and its organelles, plasma membrane, and nerve cell processes. It classifies neurons based on morphology, size, and function and provides examples of each type.
The document discusses the human digestive system. It describes the stages of digestion including mechanical digestion in the mouth using teeth and chemical digestion using enzymes. It outlines the organs of the digestive system including the mouth, esophagus, stomach, small intestine, large intestine and anus. It provides details on the functions of these organs and disorders that can affect the digestive system.
The document discusses three compounds - adenosine, ADH, and histamine - and their effects on fluid balance. It summarizes their pathways, expected effects based on known mechanisms, and experimental results measuring drip rate and weight change. The results matched expectations for adenosine and ADH based on their vasodilation and vasoconstriction effects. For histamine, drip rate increased as expected, but weight decreased instead of increased, possibly due to species differences in receptor locations.
The document summarizes urine formation and micturition. Urine is formed through glomerular filtration in the kidneys where water and small molecules pass through the glomerular membrane into the filtrate. Most of the filtrate is reabsorbed in the renal tubules, with less than 1% excreted as urine. Micturition is the process of emptying the bladder through contraction of the detrusor muscle and relaxation of the internal urethral sphincter.
The basal ganglia consist of several structures including the caudate nucleus, putamen, globus pallidus, substantia nigra, and subthalamic nucleus. They are located within the cerebral hemispheres and are involved in motor control and cognition. Two main circuits exist - the putamen circuit for executing movements and the caudate circuit for cognitive motor control. Diseases that impact the basal ganglia like Parkinson's and Huntington's result from dysfunction of neurotransmitter pathways and can cause both hyperkinetic and hypokinetic movement disorders. Common treatments involve replacing dopamine or modifying basal ganglia circuitry.
Movements in the GIT( the guyton and hall physiology)Maryam Fida
movements in GIT
1. Propulsive Movements -------- Peristalsis
2. Mixing Movements
Moves food forward along GIT at an appropriate rate for digestion and absorption
A contractile ring appears around the gut and then moves forward
Stimulation at any point in the gut can cause a contractile ring to appear in the circular muscle, and this ring then spreads along the gut tube
Directional movement toward Anus
Can occur in either direction but normally occurs towards anus
Requires active myenteric plexus
Stimulus for intestinal peristalsis
Distention of the gut
Irritation
Parasympathetic nervous signals
Peristalsis is absent:
Congenital absence of myenteric plexus
Atropine (paralyzes cholinergic nerve endings)
Peristalsis also occurs in
Bile ducts
Glandular ducts
Ureters
Many other smooth muscle tubes of the body
Law of the Gut or Peristaltic Reflex or Myenteric reflex:
Peristaltic reflex plus anal direction of movement of peristalsis is called "law of the gut”
Contractile ring normally begins on orad side of distended segment
The gut sometimes relaxes several centimeters downstream toward the anus, called "receptive relaxation," thus allowing food to be propelled easily anally
The document discusses the physiology of the kidney. It provides an overview of renal functions such as regulating water, electrolyte and acid-base balance, and excreting waste products. It describes the structure of the kidney including nephrons, glomeruli and tubules. It discusses glomerular filtration, the processes of filtration, reabsorption and secretion, and how clearance is used to measure glomerular filtration rate and renal blood flow.
The document discusses the formation of concentrated urine through a countercurrent system and urea recycling in the kidneys. It explains that concentrated urine is formed through (1) high levels of ADH hormone and (2) development and maintenance of a hyperosmotic renal medullary interstitium. This gradient is established through a countercurrent system using the loop of Henle and vasa recta blood vessels, as well as urea recycling back into the medulla. Sodium and other solutes are deposited in the medulla through these mechanisms to draw water out of the urine as it passes through the kidneys, resulting in highly concentrated urine.
The cerebral cortex is a thin sheet of neural tissue that surrounds the cerebrum. It plays a key role in functions like memory, awareness, language, and consciousness. It is divided into two hemispheres and four lobes. It has six layers and is made up of grey matter on the inside and white matter on the outside. The cortex contains several functional areas including sensory, motor, and associated areas. The sensory areas process somatosensation, vision, hearing, smell, and taste. The motor areas control voluntary movement. The associated areas integrate information for functions like cognition and language.
1. Renal blood flow is tightly regulated to maintain a constant rate of around 1200 mL/min despite wide changes in blood pressure, through mechanisms like autoregulation and tubuloglomerular feedback.
2. The kidneys receive a high blood flow of around 20-30% of cardiac output despite their small size, and oxygen consumption in the kidneys is very high, second only to the heart.
3. Blood enters the kidneys through the renal artery and is distributed through a branching network of arteries before entering the glomerular capillaries and surrounding the nephron tubules, with the renal veins collecting the blood and returning it to circulation.
Tubular reabsorption (The Guyton and Hall physiology)Maryam Fida
It is the second step of urine formation.
It is defined as;
“ The process by which water and other substances are transported by renal tubules back to blood is called Tubular Reabsorption”.
Tubular reabsorption is highly selective.
Some substances like glucose and amino acids are completely absorbed from tubules. So, the urinary excretion is zero.
Ions such as Na+, Cl-, HCO3- are highly absorbed but rate of absorption and excretion varies, according to body needs.
Materials Not Reabsorbed
Nitrogenous waste products
Urea
Uric acid
Creatinine
Excess water
The renal system consists of the kidneys and urinary bladder. The kidneys play a vital role in maintaining fluid balance and composition in the body, regulating the internal environment. The kidneys are composed of nephrons which filter blood, reabsorbing necessary substances and secreting waste products to produce urine. Urine is stored in the bladder and emptied during micturition.
The cerebellum plays an important role in motor control and coordination. It receives input from various sources, including the spinal cord, brainstem, and cerebral cortex. This input is processed within the cerebellar cortex and nuclei. The cerebellum then sends output to motor areas of the brainstem and cerebral cortex to coordinate movement, balance, and posture. It acts as a comparator, receiving feedback on actual movements and comparing them to intended movements, in order to calibrate motor output and prevent overshooting during voluntary motor acts such as walking and running. Damage to the cerebellum can cause ataxia or lack of coordination.
The document discusses the central nervous system. It begins by describing the general design of the nervous system, noting that the CNS contains over 100 billion neurons and synapses allow signals to pass in a forward direction. It then discusses the divisions of the nervous system, describing the central nervous system as consisting of the brain and spinal cord. The spinal cord functions to transmit sensory and motor signals and mediate reflexes. The document goes on to describe the structure and tracts of the spinal cord, as well as the sensory and motor parts of the nervous system. It discusses the different levels of function in the CNS including the spinal cord, lower brain, and higher brain levels. The document concludes by describing CNS synapses and various types
Nephron (The Guyton and Hall physiology)Maryam Fida
Structural and Functional unit of kidney is called nephron.
There are about 1.3 million nephron in each kidney.
New nephrons can not be regenerated by kidneys.
Functioning nephrons decrease about 10 % every 10 years at the age of 40.
At the age of 80, there are 40 % of functioning nephrons as compared to 40 yrs.
It is formed by two parts.
1. GLOMERULUS
2. BOWMAN’S CAPSULE
1- Glomerulus:
It consists of tuft of glomerular capillaries.
There is anastomosing & branching network of glomerular capillaries.
Glomerular capillaries have high hydrostatic pressure (nearly 60 mm Hg) as compared with other capillaries.
Glomerulus is surrounded by a membranous cover called Bowman’s capsule.
Each glomerulus is about 0.2 mm in diameter.
Glomerulus and Bowman’s capsule together constitute renal corpuscle.
Each renal tubule is divided into various part as they have different functions.
i- Proximal convulated tubule.
It is continuation of Bowman’s capsule.
ii- Loop of Henle. It is continuation of prox. conv. tubule.
* Loop of Henle has three parts.
a- descending limb,
b- u turn or bend in medulla and
c- ascending limb.
Ascending limb has initial thin segment followed by thick segment.
At the end of thick ascending limb, there is short segment called macula densa, which plays important role in controlling functions of nephron.
The central nervous system (CNS) and peripheral nervous system (PNS) have 3 general functions: collect information through receptors, process and evaluate information, and respond to information. Neurons communicate via action potential propagation and neurotransmitter release. The sensory division has somatic and visceral components, with visceral sensory being part of the autonomic nervous system. The motor division has somatic and autonomic components. Nervous tissue in the CNS contains glial cells and neurons. During development, the neural plate forms the neural groove and neural tube from ectoderm. The CNS contains around 100 billion neurons organized into the brain and spinal cord.
The document provides an overview of kidney anatomy and physiology. It discusses:
1. The basic functions and structures of the kidney, including filtration, homeostasis, and hormone production.
2. The anatomy of the kidney, including locations of the cortex, medulla, renal pyramids and other structures.
3. The nephron as the functional unit of the kidney, describing its role in filtration, reabsorption, secretion and other processes.
4. Key physiological concepts like the countercurrent multiplier mechanism and regulation of electrolytes and acid-base balance.
Kidney (STRUCTURE AND FUNCTIONS) (: The Guyton and Hall physiology)Maryam Fida
STRUCTURE AND FUNCTIONS OF KIDNEY
There are two kidneys in body , Rt & Lt, lying on post abdominal wall, outside peritoneal cavity.
There weight is aprx. 150 Gm and size is clenched fist.
On medial side, there is a region called hilum through which pass blood & lymphatic vessels, nerve fibers and ureterKidney is surrounded by a protective fibrous capsule.
Each kidney has two major zones, outer thick known as cortex and part known as medulla.
Medulla is divided into multiple cone shaped tissue masses called renal pyramid.
The base of pyramid begins at junction of cortex & medulla and terminates in papilla which projects into space of renal pelvis.
Renal pelvis is funnel shaped continuation of upper end of ureter.
1- Excretion of metabolic waste products such as urea, creatinine, uric acid, Bilirubin, hormones & drugs.
2-. ELIMINATE HARMFUL FOREIGN COMPOUNDS.
Such as toxins, drugs, heavy metals, pesticides.
3- Regulation of water & electrolyte balance to maintain normal homeostasis of body by re-absorption and adjustment of rate of excretion of various substances.
4- Regulation of Arterial Pressure.
*Long term regulation by excreting variable amounts of water and sodium
and
*short term by secreting vaso-active substance (renin).
Important questions of physiology for 1st year mbbs students by dr. mudassar ...Dr. Mudassar Ali Roomi
This document provides an outline of important topics in cardiac physiology, including:
1) The phases of the cardiac cycle, including isovolumic contraction and relaxation.
2) The phases of the action potential in ventricular and SA nodal fibers and what a pre-potential is.
3) The components of the cardiac conduction system and timings of impulse conduction, including what AV nodal delay is and its importance.
4) Features of the normal ECG waves, segments and intervals.
This document discusses glomerular filtration and the glomerular filtration rate (GFR). It defines glomerular filtration as the process where plasma filters through the glomerular capillaries into Bowman's capsule, the first step in urine formation. The GFR is the rate at which plasma is filtered and is an important measurement of kidney function. Normal GFR is about 125 mL/min. The kidneys filter the plasma around 60 times per day. Renal blood flow to the kidneys is high at around 1200 mL/min and is regulated by the afferent and efferent arterioles. Glomerular filtration is governed by the filtration coefficient and Starling forces of hydrostatic and oncotic pressures
This document summarizes the anatomy and physiology of the nephron, specifically the collecting tubules and juxtaglomerular apparatus. The collecting tubule is the final segment of the nephron before entering the collecting duct system. It can be divided into the cortical and medullary collecting tubules. The cortical collecting tubule reabsorbs sodium, potassium, and water. The medullary collecting tubule is responsible for acidification of urine and is permeable to water and urea. The juxtaglomerular apparatus is formed by modified cells in the afferent arteriole and macula densa. It detects changes in chloride concentration and blood pressure, triggering the release of renin and regulating the
The document provides an overview of the nervous system, including its general functions of sensation, integration, and motor response. It describes the main cell types of the nervous system as neurons, which perform the major functions, and neuroglia, which play a supporting role. Neurons are classified as afferent, interneurons, or efferent. The central nervous system consists of the brain and spinal cord, which contain gray matter for signal processing and white matter for tract formation. The peripheral nervous system connects to the central nervous system via afferent and efferent tracts in the spinal cord.
The document provides information on the historical background and structure of neurons. It discusses how Purkinje, Golgi, and Cajal contributed to understanding neurons through their research using early microscopes. Their work led to the Neuron Doctrine which established that the neuron is the fundamental unit of the nervous system. The document then describes the main structures of the neuron in detail, including the cell body and its organelles, plasma membrane, and nerve cell processes. It classifies neurons based on morphology, size, and function and provides examples of each type.
The document discusses the human digestive system. It describes the stages of digestion including mechanical digestion in the mouth using teeth and chemical digestion using enzymes. It outlines the organs of the digestive system including the mouth, esophagus, stomach, small intestine, large intestine and anus. It provides details on the functions of these organs and disorders that can affect the digestive system.
The document discusses three compounds - adenosine, ADH, and histamine - and their effects on fluid balance. It summarizes their pathways, expected effects based on known mechanisms, and experimental results measuring drip rate and weight change. The results matched expectations for adenosine and ADH based on their vasodilation and vasoconstriction effects. For histamine, drip rate increased as expected, but weight decreased instead of increased, possibly due to species differences in receptor locations.
This document describes Sixth Sense technology, a wearable gestural interface developed by Pranav Mistry. It consists of a camera, projector, and mirror attached to a pendant that is wirelessly connected to a mobile device. The camera tracks hand gestures which are processed by the mobile device to project digital information onto surrounding surfaces using the projector and mirror. Some applications include making calls, getting maps/directions, checking the time, accessing product information, and taking photos. The system allows users to interact naturally via gestures to access information about the physical world around them.
This document discusses urinary elimination and provides guidelines for assisting residents. It covers normal urination, things to report if the urine is abnormal, proper use of bedpans and briefs, performing peri-care to prevent infections, and catheter care procedures to keep the area clean.
The document summarizes urine formation and regulation of glomerular filtration rate (GFR). Urine is formed through three processes: glomerular filtration, tubular reabsorption, and tubular secretion. GFR is determined by the permeability and surface area of the glomerular capillaries as well as the net filtration pressure. The kidneys regulate GFR through mechanisms like autoregulation and the renin-angiotensin system to balance filtration and reabsorption according to the body's needs.
The document is a PowerPoint presentation on the urinary system. It summarizes the key functions and organs of the urinary system, including waste elimination and homeostasis regulation. It describes the anatomy and physiology of the kidneys, ureters, urinary bladder, and urethra. It explains how the kidneys filter blood to form urine and the processes of glomerular filtration, tubular reabsorption, and secretion.
The document provides an overview of renal physiology, including:
1) The functions of the urinary system include producing and expelling urine, regulating fluid balance, and producing hormones like renin and erythropoietin.
2) The nephron is the functional unit of the kidney and includes structures for glomerular filtration, tubular reabsorption and secretion, and urine excretion.
3) Glomerular filtration occurs due to hydrostatic pressure differences and filtration barriers, producing around 180L of filtrate per day that must be mostly reabsorbed to prevent fluid loss.
The kidneys produce urine through ultrafiltration and selective reabsorption. During ultrafiltration in the glomerulus, water and small molecules are filtered from the blood into the renal capsule. Then in the nephron tubules, useful materials like water, salts, glucose and amino acids are reabsorbed back into the blood while waste products remain and pass into the urine. The composition of urine is affected by diet and conditions like diabetes, as well as environmental factors such as temperature.
The urinary system consists of the kidneys, ureters, urinary bladder and urethra. The kidneys filter the blood to remove wastes and produce urine. The nephron is the functional unit of the kidney that filters blood and forms urine. Urine passes from the kidneys through the ureters into the bladder, and is then emptied through the urethra. Urine formation involves glomerular filtration, tubular reabsorption and secretion, and a countercurrent mechanism in the kidney. The urinary system regulates water and electrolyte balance and removes nitrogenous wastes from the body.
Acute Renal Failure (ARF) can be caused by pre-renal, renal, or post-renal factors that lead to a deterioration in renal function over hours or days. Complications of ARF include fluid overload, hyperkalemia, and acidosis. Although post-renal causes only account for 10% of ARF cases, they are important to identify and exclude as the condition may be reversible if caused by urinary tract obstruction. Indications for urgent dialysis in ARF include severe metabolic acidosis, refractory pulmonary edema, hyperkalemia over 7 mmol/L, uraemic encephalopathy, and uraemic pericarditis.
This document provides an overview of the structure and function of the urinary system. It discusses the key organs - kidneys, ureters, urinary bladder and urethra. It then focuses on kidney anatomy, including internal structures like the cortex, medulla and nephrons. Nephrons are described as the functional units that form urine, consisting of a glomerulus for filtration and renal tubules for processing. The mechanisms of blood filtration and urine production by nephrons are also summarized.
I am a medical student. I have one friend who is persuing his MBBS degree in Taishan Medical UNiversity. I got these notes from him.
These notes are by Dr. Bikesh, He is a famous lecturer of TMU.
These notes have helped me a lot and i also watch his lecture videos , which are great; highly simple and huge content.
I am uploading with Renal physiology. If you want some other topics i would upload for you.
"Let the Knowledge be spread" Dr. Bikesh
The document provides an overview of renal anatomy and physiology. It describes the microscopic structure of the nephron, including the glomerulus and its role in filtering blood. The major functions of the kidneys are also summarized, such as regulating fluid balance and electrolytes, producing hormones, and eliminating waste. Key anatomical structures involved in these functions are the glomerulus, proximal and distal tubules, as well as the surrounding blood vessel network that allows for reabsorption and secretion.
1. The document discusses fluid and electrolyte balance and disturbances, focusing on sodium, potassium, fluid volume deficits, and fluid volume excesses. It describes the regulation of body fluid compartments and how electrolyte imbalances can occur.
2. Specific electrolyte imbalances like hyponatremia, hypernatremia, hypokalemia, and hyperkalemia are explained in terms of their causes, clinical manifestations, and nursing management.
3. Critical thinking exercises are provided to help nurses understand how to assess and care for patients experiencing fluid and electrolyte disturbances like hyponatremia and hypokalemia. Monitoring, diet modifications
The document is from a chapter on the urinary system from a human anatomy and physiology textbook. It provides information on kidney functions such as filtering blood and regulating fluid balance. It describes the internal structures of the kidney including nephrons, which filter blood to form urine. Key processes in urine formation are glomerular filtration, tubular reabsorption and secretion. Factors such as blood pressure and hormones regulate glomerular filtration rate to control the production and composition of urine.
The document summarizes the key structures and mechanisms involved in urine formation by the kidneys. The glomeruli, proximal canaliculi, and distal canaliculi are responsible for filtration, reabsorption, and secretion to form urine. Filtration occurs as blood is filtered in the glomeruli, producing primary urine. Most of the filtered substances are then reabsorbed back into the bloodstream in the canaliculi. Remaining substances and waste are excreted in the final urine output, with the kidneys processing around 180 L of blood filtrate per day.
Urine is formed via glomerular filtration, reabsorption, and secretion in the nephron. Glomerular filtration is the initial process where plasma is filtered from the renal bloodstream into Bowman's capsule through small pores in the glomerular capillaries. The glomerular filtration rate measures the volume of filtrate produced per unit of time and is a key indicator of kidney function. Filtration occurs due to Starling forces and other factors that allow plasma and solutes but not cells to pass through the glomerular membrane into the filtrate.
I am a medical student. I have one friend who is persuing his MBBS degree in Taishan Medical UNiversity. I got these notes from him.
These notes are by Dr. Bikesh, He is a famous lecturer of TMU.
These notes have helped me a lot and i also watch his lecture videos , which are great; highly simple and huge content.
I am uploading with Renal physiology. If you want some other topics i would upload for you.
"Let the Knowledge be spread" Dr. Bikesh
Spermatogenesis and oogenesis both use meiosis to produce gametes. Spermatogenesis occurs in the testes and results in 4 haploid sperm from one diploid germ cell. Oogenesis occurs in the ovaries and results in one haploid egg and 3 polar bodies from the original diploid oocyte. Both processes arrest at different stages of meiosis until fertilization.
This document discusses renal physiology and osmoregulation through urine dilution and concentration. It covers plasma osmolality, how the body regulates changes in osmolality through thirst, antidiuretic hormone (ADH) secretion, and the countercurrent multiplier and exchanger mechanisms in the loop of Henle and vasa recta. These systems allow precise control of plasma osmolality and the production of dilute or concentrated urine depending on the body's needs.
This patient presented with acute onset quadriparesis due to severe hyperkalemia. Laboratory investigations revealed high serum potassium of 8.7 mEq/L, metabolic acidosis, renal dysfunction, and glucosuria. The hyperkalemia was likely due to a combination of factors - decreased renal excretion due to recent initiation of ACE inhibitors and spironolactone for hypertension, worsening of renal function due to NSAID use and UTI, and potassium shift into extracellular space due to severe hyperglycemia and acidosis. Immediate treatment focused on reducing potassium levels while the underlying causes were addressed.
The document summarizes renal functions, morphology, anatomy, urine formation, and clinical assessment of renal function. It describes the categories of acute renal failure as prerenal, intrinsic renal, or postrenal. Prerenal azotemia is caused by decreased effective blood volume or impaired renal blood flow and is reversible. Intrinsic renal azotemia directly involves the renal parenchyma, commonly from acute tubular necrosis or glomerulonephritis. Postrenal azotemia results from bilateral ureteric obstruction. Laboratory findings and urinalysis can help distinguish the three categories.
The document discusses renal and kidney function including:
1. The functions of the kidney including regulation of fluid balance, electrolytes, acid-base balance, and hormone production.
2. The structure of the nephron and how it filters blood to form urine through processes like glomerular filtration and reabsorption.
3. Factors that influence kidney function like the renin-angiotensin-aldosterone system and how different drugs can impact renal excretion and dosing considerations in renal failure.
This document discusses dyselectrolytemias (fluid and electrolyte disturbances) that commonly occur in intensive care unit patients. It notes that disturbances of sodium, potassium, chloride, calcium, phosphate, and magnesium are increased risk factors for poor prognosis. The document outlines some of the key mechanisms that can lead to electrolyte imbalances, such as reduced kidney perfusion, activation of hormonal systems, and renal tubular damage. It emphasizes that inappropriate fluid and electrolyte administration is often the most important cause of dyselectrolytemias. The document stresses that treatment must be closely monitored with serial electrolyte measurements.
This document discusses dyselectrolytemias (fluid and electrolyte disturbances) that commonly occur in intensive care units. It covers several key points:
- Fluid and electrolyte disturbances are among the most common clinical problems in ICU patients and increase morbidity and mortality. Disturbances can involve sodium, potassium, chloride, calcium, phosphate, and magnesium.
- Critical illnesses like trauma, sepsis, brain damage and heart failure can disrupt fluid and electrolyte homeostasis through mechanisms like reduced kidney perfusion, activation of hormones, and renal tubular damage. Inappropriate fluid/electrolyte administration is also important.
- Hypo- and hypernatremia are independent risk factors for poor prognosis in ICU
Diuretics and antidiuretics detail STUDYNittalVekaria
diuretics and antidiuretics detail study
-diuretic are the drug which increase the urine formation and excretion.
- antidiuretic work by decrease the urine formation.
classification, mechanism of action, use ,pharmacokinetic, pharmacodynamic,adverse effect
-newer drug
-banned diuretic and antidiuretic drug
Acute renal replacement therapy (RRT) is indicated for acute kidney injury (AKI) with severe complications such as hyperkalemia, acidosis, or fluid overload. Other indications include toxic ingestions that can be cleared by RRT like toxic alcohols, lithium, and salicylates. RRT may also be used to manage severe electrolyte imbalances other than from AKI, including sodium levels less than 110 or greater than 160 mmol/L, and hyperthermia over 40°C.
The document discusses the anatomy and physiology of the nephron, the functional unit of the kidney. It describes how nephrons filter blood to form urine via glomerular filtration. Damage to nephrons or decreased blood flow can cause acute kidney injury (AKI), also called acute renal failure (ARF). The causes, types (prerenal, intrinsic renal, postrenal), diagnosis and treatment of ARF are explained in detail. Early dialysis is important for managing complications of severe ARF like fluid overload, electrolyte abnormalities and uremia.
The urinary system filters wastes from the blood and regulates fluid balance through the kidneys and urine production. The kidneys contain nephrons which filter blood to form urine and regulate electrolyte and acid-base balance. Urine passes from the kidneys through ureters to the bladder and is eliminated through the urethra. Precise control of filtration, reabsorption and secretion allows the kidneys to regulate fluid balance and remove nitrogenous and other wastes from the body.
The document discusses the structures and functions of the nephron, the basic functional unit of the kidney. It describes the key parts of the nephron including the glomerulus, Bowman's capsule, proximal convoluted tubule, loop of Henle, distal convoluted tubule and collecting duct. It explains the role of each part in filtering the blood and reabsorbing useful substances while removing waste from the kidney filtrate to produce urine. Specifically, it details how different sections of the nephron are permeable or impermeable to water and salts to establish osmotic gradients that allow for their selective reabsorption and concentration in the urine.
Diuretics are drugs that increase urine output by interfering with sodium reabsorption in the kidneys. They are commonly used to treat hypertension by lowering blood volume and pressure. The main classes of diuretics act on different parts of the kidney tubule: loop diuretics act on the ascending loop of Henle; thiazide diuretics act on the distal tubule; and potassium-sparing diuretics act on the late distal tubule or collecting duct. While all diuretics lower blood pressure, their specific sites of action determine their degree of natriuresis and potassium retention or loss.
Diuretics are drugs that promote the excretion of sodium and water from the body by acting on the kidney. They work by interfering with sodium transport mechanisms in different segments of the nephron. The main types are loop diuretics which act on the thick ascending limb of the loop of Henle, thiazide diuretics which act on the early distal tubule, and potassium-sparing diuretics which act on the late distal tubule and collecting duct. Diuretics are important drugs used to treat hypertension, heart failure, and edema.
The document discusses kidney function and urine formation processes. It then summarizes the key functions of the kidneys, which include regulating electrolyte and fluid balance and removing waste from the blood. It describes the three main processes involved in urine formation - filtration, reabsorption, and secretion. The document then focuses on hypertension, describing classifications of blood pressure and types of hypertension. It outlines mechanisms for blood pressure control and discusses non-pharmacological and pharmacological approaches to hypertension management.
Post-obstructive diuresis refers to high urine output that can occur after relief of urinary tract obstruction. It is caused by accumulation of water, sodium, and urea during the period of obstruction. There are two main types - physiological diuresis which is self-limiting as fluid balance returns to normal, and pathological diuresis where inappropriate water loss continues beyond normalization of volume status. Treatment involves careful fluid management to replace losses based on urine output and electrolyte monitoring, as most cases will resolve spontaneously once homeostasis is restored. However, those with risk factors like edema may require closer monitoring and intravenous fluids.
This document discusses electrolyte imbalances and fluid compartments in the body. It defines key terms like osmosis, diffusion, and active transport that govern fluid and electrolyte movement. Specific electrolytes like sodium, potassium, calcium, and magnesium are explained in depth, outlining their roles, causes of imbalance, symptoms, and treatments for conditions like hyponatremia, hyperkalemia, hypocalcemia, and hypomagnesemia. Fluid compartments of intravascular, interstitial, and intracellular spaces are defined in relation to fluid movement and homeostasis in the body.
ARF is an abrupt decline in kidney function that results in a failure to excrete waste products and maintain fluid and electrolyte balance. It is characterized by azotemia, fluid overload, and electrolyte abnormalities. ARF has been replaced by the term AKI which represents a spectrum of acute impairment in kidney function defined by increases in creatinine or decreases in urine output. Prerenal, renal, and postrenal classifications are used and treatment involves identifying and reversing the underlying cause as well as managing fluid, electrolyte, and other abnormalities through restriction of intake and use of dialysis in severe cases.
The document provides an overview of renal alterations and metabolic alterations that will be covered in a PCCN review course. It includes topics like acute renal failure, electrolyte imbalances, diabetes, shock states, and sepsis. Objectives are outlined covering renal function, IV fluid therapy, electrolyte disturbances, intracranial hemorrhage, stroke, DKA, HHNK, DI, SIADH, and shock. Details are then provided on acute renal failure, electrolytes like potassium, sodium, magnesium, and glucose, as well as their related imbalances.
1. Acute renal failure (ARF) and chronic renal failure (CRF) were defined. ARF is abrupt in onset and often reversible, while CRF develops over time and is generally irreversible.
2. There are three main types of ARF - pre-renal from decreased blood flow, intrinsic/intra-renal from kidney damage, and post-renal from urinary tract obstruction.
3. Causes, pathophysiology, signs and symptoms, and diagnostic tests for ARF were outlined, along with the multiple phases ARF can progress through. Management of fluid, electrolyte, and acid-base imbalances was also discussed.
The document summarizes renal physiology and kidney function. It discusses:
1) The structure of the kidney including nephrons, collecting ducts, and microvasculature. Nephron number is established prenatally and cannot be replaced if lost.
2) Urine formation through selective retention and elimination of solutes and water by different nephron segments including the glomerulus, proximal tubule, loop of Henle, and collecting ducts.
3) Causes, types (prerenal, intrarenal, postrenal), phases, prevention and management of acute renal failure and end-stage renal disease where dialysis or transplantation is needed for survival.
1. Brown-Séquard syndrome was first described in 1850 based on observations of machete injuries in sugar cane farmers, with key features being ipsilateral motor paralysis and mixed sensory loss below the level of the spinal cord lesion.
2. Understanding the anatomy of ascending and descending spinal tracts is important for explaining the clinical features of Brown-Séquard syndrome and other spinal cord injuries.
3. Injuries can disrupt motor or sensory tracts differently, causing varying neurological deficits depending on whether the lesion involves upper or lower motor neurons.
The document discusses several inflammatory arthropathies known as spondylarthropathies. They are commonly associated with the HLA B27 gene and involve entheses, synovium, and the spine. Major types include ankylosing spondylitis, psoriatic arthropathy, reactive arthritis, and enteropathic arthritis. They often present with enthesitis, uveitis, and spondylitis and are treated with NSAIDs, DMARDs, anti-TNF drugs, or surgery depending on the specific condition and symptoms.
Lung cancer is classified into two main types - non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC). NSCLC makes up about 80% of cases and can be further divided into squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. SCLC accounts for 10-15% of lung cancers and grows more quickly. The main symptoms are cough, chest pain, and coughing up blood. Risk factors include smoking, asbestos exposure, and radiation exposure. Diagnosis involves tests such as sputum analysis, biopsies, CT scans, and PET scans to determine the cancer type and stage. Treatment options depend on the cancer type and stage but may include surgery, chemotherapy
Eczema herpeticum is a potentially life-threatening herpes infection that occurs when herpes simplex virus infects disrupted skin in patients with pre-existing skin conditions like eczema or atopic dermatitis. It presents with clusters of vesicles and punched-out erosions that spread and become hemorrhagic and crusted. Diagnosis involves identifying characteristic lesions along with fever and pain, and can be confirmed with tests like Tzanck smear, viral culture, or antibody testing. Aggressive treatment with IV acyclovir is required to prevent complications like herpes keratitis, which can lead to blindness. Early recognition and effective antiviral therapy are important given the potential severity of eczema her
The vagus nerve connects organs in the neck and below to the brainstem. It has both sensory and motor functions and helps control the heart rate, digestion, and other involuntary processes. Stimulation of the vagus nerve has been shown to reduce seizures, experimental pain, and inflammation, and may help treat conditions like epilepsy, obesity, and heart disease. Damage to the vagus nerve or its connections in the brainstem can impact swallowing, heart rate variability, and level of consciousness.
Poor water and sanitation are responsible for a huge global burden of disease, with contaminated water alone contributing to about 2.4 million preventable deaths per year, mainly in children. While progress has been made in increasing access to safe water and improved sanitation, current rates of progress will not meet the Millennium Development Goal targets. Water and sanitation remain a low priority on international development agendas despite their importance for health and achieving the MDGs. Coordinated efforts are still needed to address this critical issue.
This document discusses medical student electives in developing countries. It notes potential benefits like exposure to rare diseases and personal growth, but also flags ethical issues. Electives could exploit local health systems and raise false expectations. They may perpetuate neo-colonial practices by benefiting students and health systems in wealthy countries more than local populations. The document also examines how non-governmental organizations can undermine public health systems and calls for electives to minimize harm, respect local needs, and establish long-term exchange programs to provide mutual benefit.
This document provides an overview of global health by defining key terms, outlining major players and organizations, and summarizing the history and evolution of the field from 1945 to the present day. It describes how global health has shifted from a focus on infectious disease control to addressing social determinants of health and health issues that transcend national borders. Major milestones discussed include the founding of the UN and WHO, the Alma-Ata Declaration, structural adjustment policies, the Millennium Declaration and MDGs, debt relief campaigns, and the establishment of the Global Fund. The summary highlights the ongoing tension between disease-specific and comprehensive primary healthcare approaches.
The document discusses how international organizations like the WTO and treaties it has established like TRIPS and GATS impact healthcare. The WTO aims to liberalize trade and its dispute process enforces agreements. TRIPS established intellectual property standards that require drug patenting, raising prices. Some countries like Brazil and South Africa have issued compulsory licenses to produce cheaper generics, facing opposition from pharmaceutical companies but helping improve access to treatment.
Global health examines influences on health across borders, including issues like globalization, poverty, and human rights. It draws from multiple disciplines. Globalization refers to reducing barriers between countries, leading to increased trade, investment, and communication. This has effects like economic growth but also rising inequalities. Agreements like TRIPS have increased pharmaceutical patent protection globally, raising concerns about access to medicines, especially in developing countries. Networks of both commercial and civil society actors have been important in debates over balancing intellectual property with public health.
Migration of health care workers has both positive and negative effects on health. It reduces the availability of health services in source countries while increasing access in destination countries. This unequal distribution of health workers is driven by push factors like low pay and poor working conditions in source countries and pull factors like higher wages in destination countries. As a result, source countries experience worse health outcomes due to lack of health workers, while destination countries receive an indirect subsidy through the receipt and employment of trained medical professionals from poorer nations. Proposed policy responses aim to strengthen health systems in source countries, implement ethical recruitment practices, and foster partnerships between nations to promote more equitable health worker distribution.
Global institutions play major roles in health financing and policy. The key players discussed are the World Health Organization (WHO), World Bank, International Monetary Fund (IMF), and World Trade Organization (WTO). The WHO is the UN agency for health, working with 192 member states. The World Bank aims to reduce poverty through loans and policy advice to developing countries. The IMF promotes international monetary cooperation and provides temporary financial assistance. The WTO, formed in 1995, ensures trade flows freely through treaties and enforcement mechanisms, which some criticize can undermine public health systems.
Haemochromatosis is an autosomal recessive condition characterized by excessive iron accumulation in the body. It affects around 0.5% of Caucasians and usually presents in the 40s-50s with a triad of pigmentation, diabetes mellitus, and hepatomegaly. Diagnosis involves blood tests showing elevated serum iron, transferrin saturation over 50%, and elevated serum ferritin. Liver biopsy can confirm iron deposition and damage. Treatment aims to reduce iron stores through weekly venesection of 1 unit of blood for 6-12 months followed by maintenance venesection.
Ascites is an abnormal collection of fluid in the peritoneal cavity, commonly caused by portal hypertension due to cirrhosis. It results from sodium and water retention triggered by vasodilation and activation of the renin-angiotensin system, as well as increased hydrostatic pressure and transudation of fluid from the liver and spleen into the peritoneal cavity. Hypoalbuminemia due to decreased liver function also contributes by reducing plasma oncotic pressure. Spironolactone is used as treatment as it is an aldosterone antagonist. Management involves dietary sodium restriction, diuretics, stopping alcohol, monitoring for complications, and procedures such as paracentesis or shunts.
The liver has two lobes, separated by veins, and is divided into sections supplied by individual blood vessels. Blood flows through hepatic arteries and portal veins into sinusoids, where waste is filtered by Kupffer cells in the space of Disse before draining into hepatic veins. The liver performs many functions including synthesizing proteins, metabolizing carbohydrates and lipids, and detoxifying hormones and drugs. Liver function can be assessed through blood tests of enzymes and proteins.
Antidepressants such as SSRIs, TCAs, and MAOIs work by increasing levels of serotonin, norepinephrine, or both in the brain. SSRIs are generally first-line treatment and safer in overdose than TCAs, but TCAs may be better for severe depression. Both classes of drugs can cause side effects like dry mouth, nausea, and sexual dysfunction. Antidepressants may take 10-20 days to work and should be continued for at least 6 months after symptoms improve to prevent relapse. Combining certain antidepressants can be dangerous due to increased serotonin levels.
Gout is caused by deposition of uric acid crystals in the joints, which leads to acute inflammation. It typically presents as sudden severe pain, swelling and redness in one joint, most commonly the big toe. Diagnosis is made based on symptoms and identification of crystals in joint fluid under polarized microscopy. Treatment involves medications to reduce symptoms during acute attacks as well as long-term drugs like allopurinol or probenecid to lower uric acid levels and prevent future episodes. Without treatment, gout can progress to a chronic stage with multiple joint involvement and growth of tophi deposits in the tissues.
Review of orthopaedic services: Prepared for the Auditor General for Scotland...meducationdotnet
1. Orthopaedics is a large specialty that treats musculoskeletal conditions through surgery, medication, and rehabilitation. It accounts for a significant portion of NHS spending and activity in Scotland.
2. Waiting times for orthopaedic services have reduced in recent years through changes to service delivery and additional funded activity. However, further improvements to meet 18-week referral targets will be challenging to sustain.
3. There is variation in orthopaedic efficiency across Scotland that is not fully explained by resources or procedures. The report finds opportunities to use existing resources more efficiently through measures like increasing day surgery and reducing hospital length of stay.
This document discusses the use of muscle relaxants in anesthesia and the potential role of sugammadex as a reversal agent. It provides background on why muscle relaxants are used, types of muscle relaxants, and current problems with reversal agents. It then summarizes research on sugammadex, which appears to be a more effective reversal agent than anticholinesterases, allowing faster recovery from neuromuscular blockade. Sugammadex may allow safer use of muscle relaxants and replace agents like suxamethonium, but economic factors will also influence its adoption.
This document contains a series of slides related to ophthalmology. It tests the reader's knowledge on topics like visual acuity measurements, refractive errors, eye abnormalities, causes of vision loss, and eye examination techniques. The slides include images showing conditions like cataracts, glaucoma, retinal detachments, and more. Key details are provided about diagnoses, symptoms, investigations, and treatments.
3. Renal Physiology
• Nephron
– Functional unit
– From Bowman’s capsule to
collecting duct
– 2 types
• Cortical (superficial)
– Majority
• Juxtamedullary
– Longer LoH
4. Renal Physiology
• Massive concentrating ability - GFR 120 ml/min => Urine 1 ml/min
• 2 main processes
– Filtration [Bowman’s capsule]
– Reabsorption [Everywhere else]
• Water tends to follow Na+
[Na transport central]
5. Renal Physiology
• Proximal convuluted tubule
– 70% filtered Na reabsorbed
– Active & Iso-osmotic - Volume reduction only
6. Renal Physiology
• Loop of Henle
– Active Na reabsorption only in Thick ascending limb
• Water impermeable
• Rise in medullary osmolality
7. Renal Physiology
• Loop of Henle
– Descending limb can lose water and ions
• Concentrated and dehydrated
– Fluid in ascending limb becomes dilute
• Na loss
12. Renal Physiology
• Renal blood supply
– Glomerular filtration is not energy-intensive
– Most energy (and O2) use in the kidney is for
Na/K/ATPase active pumps: Na reabsorption
• Mainly in thick ascending limb of LoH
13. Renal Physiology
• Blood flow to nephron
– Hairpin-bend arrangement
– Highest O2 consumption in outer medulla
• Blood leaving capillary bed hypoxic
• O2 tends to leave capillaries on entering to diffuse across (close apposition)
– Medulla therefore hypoxic
• Of most concern in outer medulla
14. Renal Physiology
• Problems
– Highest energy consumption in area with relative hypoxia
– Hypotension
• Glomerular filtration hydrostatic pressure initially maintained:
afferents dilate (flow remains)
• Blood flow still relatively maintained to outer medulla
– Allows concentration to continue
• Feedback mechanism reduces glomerular filtration
– Reduces energy expenditure by medulla
– Reduces Na loss
15. Renal Physiology
Glomerular blood flow
• If autoregulation fails…
– <70mmHg
– Flow becomes pressure
dependant
– Filtration therefore falls…
– And if GFR falls, then less
can be excreted.
16. Renal Failure
• So…
– Renal failure often the effect of distant
processes
– “Innocent bystander”
• But…
– Early intervention can reduce likelihood
17. Renal Failure
• What is it?
– Sudden (usually) reversible failure of kidneys to
excrete nitrogenous and other waste
– Multiple definitions
– Now: ADQI
• Review evidence
• Set research agenda
• Make management recommendations
In acute renal failure, and use of renal replacement
23. Renal Failure
• Does renal failure matter?
– Acceptable casualty??
– Another organ failure??
24. Renal Failure
• Renal failure is an independent risk
factor for mortality
– Levy et al (1996): similar illness severity
with renal failure-up to x6.5 risk of death
– CCMed (2002): similar disease severity
and renal failure x2 mortality of those
without renal failure
25. Renal Failure
• Balancing
– Optimal support for all organ systems
– Overall patient support
Means kidneys sometimes do suffer
Remember this is not benign!
26. Urine Acidification
• PCT: Na-H exchange
– Na-K-ATPase
• Catalysed by Carbonic Anhydrase
• DCT/CD: H loss independent of Na in
tubular lumen
– ATP driven proton pump
• Stimulated by aldosterone
27. Urine Acidification
• Maximum gradient against which
transport mechanisms can secrete
corresponds to urine pH 4.5
• Buffers allow more H secretion
H+
+ HCO3
-
H2CO3 (C. Anhydrase: PCT only)
H+
+ HPO4
2-
H2PO4
-
(DCT / CD)
H+
+ NH3 NH4
+
(PCT and DCT)
28. • Carbonic anhydrase is in PCT
– Allows formation of CO2 and H2O in tubular
fluid
• CO2 diffuses across membranes, becoming
available to form H2CO3
• Since most of H+
removed from tubule, pH of
fluid changes little
29. Drug Effects
• Alcohol: inhibits vasopressin
• Caffeine: inhibits vasopressin
• CA inhibitors: decrease H secretion; resultant rise in
Na and K loss
• Metolazone, thiazides: Inhibit Na-Cl cotransport in
early DCT
• Loops: inhibit Na-K-2Cl cotransporter in medullary
thick ascending LoH
• K-sparing naturietics: inhibit Na-K exchange in CD by
inhibiting aldosterone
Editor's Notes
First, the boring bits:
Kidneys (2 of them usually): Outer cortex and Inner medulla.
They:
Remove fluid; Remove electrolytes; Remove metabolic waste
The mechanisms are tightly controlled in health to ensure homeostasis.
Kidneys receive around 20% of cardiac output (400mls/100g/min): around 1 litre / min.
The functional renal unit-the nephron-starts with the Bowman’s capsule, where initial filtration occurs.
There are 2 ‘types’ of nephron:
The majority are cortical (or superficial), with a short loop of Henle
Just over 10% are juxtamedullary, with loops of Henle descending into the outer medulla.
They have a massive ability to concentrate: they filter about 120mls per minute of glomerular filtrate, and from this, they produce around 1ml of urine per minute.
There are 2 main processes: filtration and reabsorption.
Filtration happens at the Bowman’s capsule, producing fluid having basically the same composition as plasma, without the plasma proteins.
Reabsorption takes place in the rest of the nephron.
In the PCT, around 70% of the filtered Na is reabsorbed (by active transport mechanisms); Cl follows, and the osmotic gradient draws water out of the tubule. This results in a reduction in volume, with no change in osmolality.
In the Loop of Henle, active Na reabsorption happens only in the thick ascending portion of the loop.
This area is not permeable to water, so the osmolality in the medullary interstitium rises (helped by a countercurrent multiplier system).
The descending limb can lose ions and water, so as it passes through the medulla, it is concentrated and reduced in volume.
As fluid passes up the ascending limb, it actually becomes more DILUTE as Na is lost (finishing at 100 mOsmol/kg).
Most of the remaining Na is reabsorbed in the DCT, partially under the control of aldosterone.
Water is reabsorbed in the DCT and collecting duct, as it passes through the high osmolality of the medulla on the way to the renal pelvis.
It’s here that the final concentrating of the urine occurs, depending on the osmolality generated in the medulla, and the degree of permeability of the collecting duct allowed by ADH.
The blood supply to the glomerulus (from the renal artery) is via afferent arterioles, with glomerular capillary drainage via efferent arterioles.
The presence of these afferent and efferent arterioles means tight autoregulation of the blood flow across the glomerulus: if systemic arterial pressure falls, the afferents dilate, reducing renal vascular resistance, to limit the decrease in blood flow; filtration can therefore continue.
Blood flowing from the efferent arterioles then enters a second capillary system, surrounding the loop of Henle: the vasa recta.
Now, the main reason some of the nephrons extend deep into the outer medulla is that this affords them excellent concentrating ability. The vasa recta allows a hypertonic medulla, but means this area is relatively hypoxic.
The main area in which concentrating takes place is the thick ascending limb of the loop of Henle, where active sodium reabsorption occurs, using the Na/K/ATPase pump.
Fine, but this requires significant amounts of energy, as it’s an active process.
The arrangement of the vasa recta is something like this (slide): hairpin bend.
While overall renal oxygen consumption is relatively low, in the outer medulla, where active sodium reabsorption tends to occur, oxygen extraction is very high.
Blood leaving the vasa recta tends to be relatively hypoxic, and because the 2 limbs are so closely apposed, oxygen diffuses across the capillaries before they enter the medulla proper. This is the downside of a system designed to maintain a very concentrated interstitium to facilitate the reabsorption process.
As a result, the part of the kidney with the highest oxygen usage is operating on the edge of aerobic metabolism, at around 2kPa.
I’ve mentioned that autoregulation aims to maintain glomerular perfusion;
when the kidney is faced with reduced blood flow, such as when someone is hypotensive
The first thing that happens is afferent dilation to maintain forward flow through the glomerulus.
Renal blood flow redistributes from the cortex to preferentially maintain perfusion to the outer part of the medulla. This allows filtration to occur in the nephrons with the longest loops of Henle, maximizing the ability of the kidneys to concentrate urine, so minimizing fluid loss, while still excreting waste products.
A feedback mechanism (tubulo-glomerular feedback) kicks in when interstitial blood flow falls (because the maintenance of glomerular flow has meant efferent constriction now, as well as afferent). This mechanism lets the kidney reduce its oxygen requirement by reducing the volume of glomerular filtrate, and therefore the quantity of sodium needing reabsorbed.
Blood flow to the medulla is maintained until the resistance to flow exceeds the input pressure. At this point, perfusion is lost.
Fine, so that’s all well and good, but what actually happens in the real world.
Often, renal failure occurs as the effect of the body’s attempts at self preservation in the face of severe illness, often referred to as the Innocent bystander.
The thing is, the outcome can be affected, either made worse or better, by our intervention.
Now, as an aside, what exactly is renal failure?
It could be defined as the sudden (usually reversible) failure of kidneys to excrete nitrogenous and other waste products.
The problem is that previously there were many definitions, leading to confusion.
This has now been streamlined and clarified with the Acute Dialysis Quality Initiative producing the RIFLE criteria.
ADQI was set up in 2000 to look critically at renal failure: the evidence for treatment, what needed further research, and how certain conditions should be managed.
Thankfully, fairly early on, they realized that having come across over 30 definitions for acute renal failure, a major problem was the lack of any clear consensus definition.
In 2004 they published their international consensus classification for acute kidney injury: RIFLE.
We now have standardized definitions based on either GFR criteria (change in GFR or change in Creatinine) or urinary output criteria: the Urinary output was included to improve sensitivity, and increase awareness of the potential reversibility in the early stages.
There are 3 grades of injury severity:RiskInjuryFailure
With 2 outcome classes:LossEnd stage kidney disease
Note that RIFLE “F” is present if the rise in creatinine is less than x3, as long as the new creatinine is over 4mg/dl (eqv to 350micromols/l), with a rise of at least 40micromols/l.
These criteria have been studied subsequently in differing environments, including medical intensive care, cardiothoracic surgery, trauma, and found reliable, easy to use and repeatable.There is a continuum here, from reversible oliguria, to established disease. This is why identifying problems earlier and treating the cause, may help prevent development of established renal failure.
What causes acute renal failure?
The most important question to be answered is: is the renal impairment caused by a pathological process outside or within the kidney?
Often, renal failure is the result of several insults.
Paper in Critical Care Medicine 2001 (Bellomo), looking at the epidemiology, management, and outcome of severe ARF of critical illness in Australia.
They found the most common reasons for patients developing ARF were
Ischaemia/hypotension
Severe sepsis/septic shock
Acute lung disease (usu. Pneumonia)
Myocardial pump failure
Rhabdomyolysis
Nephrotoxic drugs
Patients with certain pre-morbid conditions
Have an impaired ability to compensate and therefore are more vulnerable to insults
In ICU, many patients already have these problems, compounded by a bucketload of medications…
Such that the background of limited reserve, along with
Hypovolaemia
Hypotension
Sepsis
Loss of autoregulation
Drugs
Some specific toxins
Can all lead to ischaemia of the outer medulla with death of the proximal and thick ascending limb tubular cells, resulting in established ARF.
Before I go on to what we can do about this, I want to ask: does it really matter?
After all, if someone’s kidneys fail, can’t we just stick them on a washing machine and that’s that?
Well, and probably fairly obviously if I’m asking the question, That’s not just the end of it!
There’s lots of evidence out there that it’s not just a bit of an inconvenience, but the development of ARF can significantly affect outcome.
Certainly, in general, people don’t die OF renal failure, but
1996: Levy et al JAMA Looked at almost 200 patients with renal failure due to contrast nephropathy, and compared them to a group with the same severity of illness but no renal failure. They felt renal failure contributed a x6.5 risk of death with similar severity scoring.
Several studies in post-cardiac surgery patients, showing that development of renal failure elevates risk of death.
Large multi-centre study in Critical Care Medicine 2002 looking at ICU patients: almost 900 with ARF out of 17000.
Of patients with similar disease severity, those with renal failure had a mortality almost twice that of those with no renal failure.
I’m not going into the details of all of this, and while remembering that a lot of the detail of managing a patient in ICU means walking a line between support for ALL their organ systems, which does sometimes mean allowing renal function to suffer to allow other systems to recover.
The point is that renal failure is not benign. So, if we can prevent it, surely we should try??