fourth important cation , Second most abundant cation in intracellular fluid after K+., co- factor for more than 300 enzymes , functions of magnesium,Mg-ATP substrate , Mg-GTP substrate, ATP metabolism, muscle contraction and relaxation,normal neurological function and release of neurotransmitters are Mg dependent, green leafy vegetables are particularly rich in magnesium. Absorption in intestine and re absorption in Kidney .Paracellular -Claudin-16/-19, TRPM 6/ 7. Factor affecting for absorption and res absorption ,Action potential conduction in nodal tissue. Neuromuscular Irritability,As Constituent of Bones and Teeth: Hypomagnesemia Causes of Hypomagnesemia -Decreased intake, Redistribution from extracellular to intracellular, Increased losses -Renal Gastrointestinal. hypermagnesemia. sing and symptom of Mg deficiency, familial hypomagnesemia . Hypomagnesemia clinical manifestation, endocrinological manifestation , biochemical manifestation, method of estimations , calmagite , methylbule, Xylidyl blue, forzaman dye, enzymatic method, Magnesium Tolerance Test
fourth important cation , Second most abundant cation in intracellular fluid after K+., co- factor for more than 300 enzymes , functions of magnesium,Mg-ATP substrate , Mg-GTP substrate, ATP metabolism, muscle contraction and relaxation,normal neurological function and release of neurotransmitters are Mg dependent, green leafy vegetables are particularly rich in magnesium. Absorption in intestine and re absorption in Kidney .Paracellular -Claudin-16/-19, TRPM 6/ 7. Factor affecting for absorption and res absorption ,Action potential conduction in nodal tissue. Neuromuscular Irritability,As Constituent of Bones and Teeth: Hypomagnesemia Causes of Hypomagnesemia -Decreased intake, Redistribution from extracellular to intracellular, Increased losses -Renal Gastrointestinal. hypermagnesemia. sing and symptom of Mg deficiency, familial hypomagnesemia . Hypomagnesemia clinical manifestation, endocrinological manifestation , biochemical manifestation, method of estimations , calmagite , methylbule, Xylidyl blue, forzaman dye, enzymatic method, Magnesium Tolerance Test
Dr. Sachin Verma is a young, diligent and dynamic physician. He did his graduation from IGMC Shimla and MD in Internal Medicine from GSVM Medical College Kanpur. Then he did his Fellowship in Intensive Care Medicine (FICM) from Apollo Hospital Delhi. He has done fellowship in infectious diseases by Infectious Disease Society of America (IDSA). He has also done FCCS course and is certified Advance Cardiac Life support (ACLS) and Basic Life Support (BLS) provider by American Heart Association. He has also done a course in Cardiology by American College of Cardiology and a course in Diabetology by International Diabetes Centre. He specializes in the management of Infections, Multiorgan Dysfunctions and Critically ill patients and has many publications and presentations in various national conferences under his belt. He is currently working in NABH Approved Ivy super-specialty Hospital Mohali as Consultant Intensivists and Physician.
This chapter is largely about the water and electrolytes ( salts )in your plasma and how the body manages to keep you from drying up and blowing away even if you are in the hot Texas sun and without liquid drink.
Calcium metabolism disorders
1. CALCIUM METABOLISM DISORDERS
2. OVERVIEW: Calcium definition and requirement . Calcium metabolism regulators : VD , PTH and calcitonin. Functions of calcium. Calcium metabolic bone diseases. Calcium metabolism disorders. CASE !!
3. WHAT IS CALCIUM? Calcium is a mineral that is essential to bone health, cardiovascular health, muscle maintenance, circulatory health, and blood clotting. Calcium also acts as an enzyme activator. While calcium is found in milk and dairy products, it is also available from other food sources, such as green leafy vegetables, seafood (eating salmon with the bones provides an even greater dose), almonds, blackstrap molasses, broccoli, enriched soy and rice milk products, figs, soybeans and tofu.
Dr. Sachin Verma is a young, diligent and dynamic physician. He did his graduation from IGMC Shimla and MD in Internal Medicine from GSVM Medical College Kanpur. Then he did his Fellowship in Intensive Care Medicine (FICM) from Apollo Hospital Delhi. He has done fellowship in infectious diseases by Infectious Disease Society of America (IDSA). He has also done FCCS course and is certified Advance Cardiac Life support (ACLS) and Basic Life Support (BLS) provider by American Heart Association. He has also done a course in Cardiology by American College of Cardiology and a course in Diabetology by International Diabetes Centre. He specializes in the management of Infections, Multiorgan Dysfunctions and Critically ill patients and has many publications and presentations in various national conferences under his belt. He is currently working in NABH Approved Ivy super-specialty Hospital Mohali as Consultant Intensivists and Physician.
This chapter is largely about the water and electrolytes ( salts )in your plasma and how the body manages to keep you from drying up and blowing away even if you are in the hot Texas sun and without liquid drink.
Calcium metabolism disorders
1. CALCIUM METABOLISM DISORDERS
2. OVERVIEW: Calcium definition and requirement . Calcium metabolism regulators : VD , PTH and calcitonin. Functions of calcium. Calcium metabolic bone diseases. Calcium metabolism disorders. CASE !!
3. WHAT IS CALCIUM? Calcium is a mineral that is essential to bone health, cardiovascular health, muscle maintenance, circulatory health, and blood clotting. Calcium also acts as an enzyme activator. While calcium is found in milk and dairy products, it is also available from other food sources, such as green leafy vegetables, seafood (eating salmon with the bones provides an even greater dose), almonds, blackstrap molasses, broccoli, enriched soy and rice milk products, figs, soybeans and tofu.
This presentation looks at sodium and how it affects you. Sodium is one of the body’s three major electrolytes that help to control the fluids going in and out of the body’s tissues and cells, the other two are potassium and chloride.
Sodium is part of sodium chloride, which is ordinary table salt and is also a seasoning and a preservative
detail description about the fluid and electrolyte balance. fluids and electrolytes needed during surgeries and during trauma are described. a note is added on acid base balance in the body
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
1. Potassium and Sodium Metabolism
Dr Zahid Azeem
AJK Medical College
Muzaffarabad
For. . MBBS- batch-2018
2. DEFINITION
Sodium is the most abundant ion of the
extra cellular compartment.
Water is the most abundant constituent of
the body 50% of body weight in women &
60% of the body wt in men is water, out
of which 40% is intracellular and 20% is
in extracellular compartment.
Total body water
(60% of body wt
I.C.F. (40 of
body wt)
E.C.F. (20% of
body wt)
Interstitial fluid
15%
Intravascular 5%
4. SODIUM
• Sodium -> the a abundant cation of ECF
• Sodium salts -> important part of
osmotically active solutes in plasma &
interstitial fluid.
• Sodium and its corresponding anions
represent almost all of the osmotically active
solutes in the extracellular fluid under normal
conditions…………. Tonicity
.
5. Small changes in osmolality are
counteracted by thirst regulation,
antidiuretic hormone (ADH) secretion, and
renal concentrating or diluting
mechanisms.
Preservation of normal serum osmolality
(i.e., 285-295 mOsm/L) guarantees
cellular integrity by regulating net
movement of water across cellular
membranes.
6. ADH
Its mechanism of action
•ADH is also called arginine vasopressin or
simply vasopressin.
•ADH is a small peptide hormone
produced by the hypothalamus that binds
to the vasopressin 1 and 2 receptors
(V1 and V2).
•Vasopressin release is regulated by
osmoreceptors in the hypothalamus, which
are sensitive to changes in plasma osmolality
of as little as 1 % to 2%.
7. •Under hyperosmolar conditions,
osmoreceptor stimulation leads to stimulation
of thirst and vasopressin release.
These two mechanisms result in increased
water intake and retention, respectively.
•Vasopressin release is also regulated by
baroreceptors in the carotid sinus and aortic
arch; under conditions of hypovolemia, these
receptors stimulate vasopressin release to
increase water retention by the kidney.
8. Regulatory systems
Detects ECF volume changes
Detects Sodium concentration
Modify rate of sodium
absorption/excretion
SODIUM HOMEOSTASIS
9. DEFENSE OF ECF VOLUME ANDDEFENSE OF ECF VOLUME AND
IONIC COMPOSITION OF THE BODYIONIC COMPOSITION OF THE BODY
Angiotensin
Angiotensin -I
Angiotensin -II
Hypothalamus
ADH
Thirst
Hypovolemia
Hyperosmalarity
Vasoconstriction
Adrenal cortex
Aldosterone
Kidney
Na+, water
retention
Renin
ACE
10.
11. KIDNEY -- > homeostasis
At a GFR of 125 ml/ min &
serum sodium -> 145 mmol/L ,
kidney filters > 26 mol/ day of sodium ( 1.5
kg of NaCl )
More than 99% of filtered sodium is
reabsorbed along nephrons
12. In KIDNEY :
Sodium is reabsorbed along different
segments of nephrons :
1) 50-75 % of filtered sodium reabsorbed
via secondary active co transporters
2) Thin ascending loop of Henle doesn’t
reabsorb sodium
3) Thick ascending loop of Henle reabsorbs
20-25%
13. 4) Distal convoluted tubule:
i) early DCT : 5-10% reabsorption by NaCl
co transporter
ii) late DCT : 2-5% enters here
* fine regulation, under control of
Aldosterone
* Although sodium reaching here is a small
fraction of filtered sodium, it is here where
it is decided how much sodium will be
excreted
14. Hyponatremia
Hyponatremia is defined as a serum
sodium concentration lower than
136 mmol/L.
Hyperglycemia can also cause
hyponatremia, via osmotically
induced water movement from cells
into the blood (translocational
hyponatremia)
15. Hyponatremia in a patient with
hypovolemia
Hypovolemic hyponatremia represents a
decrease in total body sodium in excess of
a decrease in total body water.
REASONS;
Simultaneous sodium and water loss can
be due to renal
(such as diuretic use) or extrarenal causes.
16. Hypovolemia results in a decrease in renal
perfusion, a decrement in the glomerular filtration
rate, and an increase in proximal tubule
reabsorption of
sodium and water;
18. Increase in total body water exceeds increase in
total body sodium. Patients are edematous.
RENAL CAUSES(urinary sodium > 20mEq/L): Acute
or Chronic renal failure
NON RENAL CAUSES: CHF, Cirrhosis, nephrotic
syndrome
Hypervolemic Hyponatremia
19. In general, hypervolemic hyponatremia
due to an extrarenal cause is
characterized by a low urine sodium
concentration (<10 - 20 mEq/L)
This distinguishes it from hypervolemic
hyponatremia due to intrinsic renal
causes, where the urine sodium is > 20
mEq/L
{ In renal causes, kidney can not
re-absorb Na } .
20. Patient has a normal store of sodium but an
excess of total body water
The most common form seen in hospitalized
patients. The most common cause is the
inappropriate administration of hypotonic fluid
The syndrome of inappropriate antidiuresis is the
most common cause of euvolemic hyponatremia
Euvolemic Hyponatremia
21. Clinical Signs of Hyponatrema
Nausea, vomiting, anorexia, muscle
cramps, confusion, and lethargy, and
culminate ultimately in seizures and
coma.
Seizures are quite likely at [Na+
] of
113 mEq/L or less.
22. Hypernatremia
Defined as a serum sodium
concentration greater than 145
mEq/L, occurs when too little total
body water exists relative to the
amount of total body sodium, thereby
raising the sodium concentration.
23. An increase in serum sodium
concentration is almost always a
reflection of water loss rather than
sodium gain.
Water loss results in the development
of plasma hyperosmolality; via
hypothalamic sensors, this acts as a
stimulant to thirst and production of
ADH.
24. •Given that even small rises in the serum
osmolality trigger the thirst mechanism,
•Hypernatremia is relatively uncommon
unless the thirst mechanism is impaired or
access to free water is restricted.
As a result, hypovolemic hypernatremia
tends to occur in the very young, the very
old.
25. It is typically due to extracellular fluid
losses accompanied by inability to
take in adequate amounts of free
water.
Febrile illnesses, vomiting,
diarrhea, and renal losses are
common causes.
26. Hypervolemic hypernatremia
Although uncommon. Sodium bicarbonate
injection during cardiac arrest,
administration of hypertonic saline solution
and inappropriately prepared infant
formulas are several examples of induced
hypernatremia.
28. How much sodium does the patient
need?
Sodium deficit = Total body
water x (desired Na – actual
Na)
Total body water is estimated as
lean body weight x 0.5 for
women or 0.6 for men
29. Question:
In elderly patients :
Decreased GFR with age limits ability to
excrete sodium prone to over expansion
of ECF
Why Hyponatremia?????????????
Impaired thirst mechanism with decreased
ability to concentrate urine
Why Hypernatremia????????
31. BODY POTASSIUM
-K+ is the major intracellular ion
-serum potassium is normally regulated within a narrow
range of 3.5 to 5.0 mmol/L.
-75% of which is in skeletal muscles
-K+ is taken up by all cells via the Na-K ATPase pump
-K+ is one of the most permeable ion across cell
membranes and exits the cells mostly via K channels (and
in some cells via K-H exchange or via K-Cl cotransport)
32. Introduction
The total body stores are approximately 50 to 55
meq/kg.
The main intracellular cation.
98% located ICF,150 meq/L.
2% located ECF,4meq/L.
90% readily exchangeable
10% non exchangeable
Amount ingested = up to 100meq/d = 2.5 gm/d
92% urinary excretion
8% GIT excretion
32
34. potassium homeostasis
External potassium balance is determined by rate of potassium intake
(100 meq/day) and rate of urinary (90 meq/day) and fecal excretion
(10 meq/day).
Internal potassium balance depends on distribution of potassium between
muscle, bone, liver, and red blood cells (RBC) and the extracellular fluid (ECF).
36. Potassium homeostasis
1.Internal balance ( ICF and ECF K+ distribution)
2. External balance ( Renal excretion of K+)
1.Internal balance
Physiological and pathological conditions can influence this
process.
o Hormones like insulin , catecholamines ,aldosterone
o Acid base imbalance
o Changes in osmolarity
o Exercise
o Cell lysis
37. Hormonal control of K+ homeostasis
Insulin and beta 2agonsists shifts K+ to the cell, by increase the
activity of Na+
,K+
-ATPase, the 1Na+
-1K+
-2Cl-
symporter, and the
Na+
-Cl-
symporter.
Aldosterone acting on uptake of K+
into cells and altering urinary
K+
excretion.
Stimulation of α-adrenoceptors releases K+
from cells, especially
in the liver.
insulin and epinephrine act within a few minutes, aldosterone
requires about an hour to stimulate uptake of K+
into cells.
02/12/15 37Potassium homeostasis and its
renal handling
40. Miscellaneous factors …..
1.Acid base imbalance
Metabolic acidosis increases the plasma [K+
].
Metabolic alkalosis decreases the plasma [K+
] .
2.Plasma osmolarity
Hyperosmolarity associated with hyperkalemia .
A fall in plasma osmolality has the opposite effect.
3.Cell lysis
o Crush injury,burns,tumor lysis syndrome, rhabdomyolysis
associated with destruction of cells and release of K+
to ECF.
4. Exercise
vigorous exercise, plasma [K+
] may increase by 2.0 mEq/L.
42. Renal handling of potassium
The PCT reabsorbs about 67% of the filtered K+
under most
conditions by K+
-H+
exchanger and K+
-Cl-
symport.
20% of the filtered K+
is reabsorbed by the TALH.
The distal tubule and collecting duct are able to reabsorb or
secrete K+
.
02/12/15 Potassium homeostasis and its
renal handling
42
43. ……….cont’d
The rate of K+
reabsorption or secretion by the
distal tubule and collecting duct depends on a
variety of hormones and factors.
Most of the daily variations in potassium excretion
is caused by changes in potassium secretion in the
distal and cortical collecting tubules.
02/12/15 Potassium homeostasis and its
renal handling
43
45. K+
SECRETION BY PRINCIPAL CELLS
Secretion from blood into the tubule lumen is a two-step
process:
1.uptake of K+
from blood across the basolateral membrane by
Na+
,K+
-ATPase and
2. diffusion of K+
from the cell into tubular fluid via K+
channels.
Three major factors that control the rate of K+
secretion by the
distal tubule and the collecting duct
A. The activity of Na+
,K+
-ATPase .
B. The driving force (electrochemical gradient) for movement of
K+
across the apical membrane.
C. The permeability of the apical membrane to K+
.
46.
47. Cellular K buffering
When K is added to the ECF, most of the added K is
taken up by the cells, reducing the ECF K+ increase
If K is lost from the ECF, some K+ leaves the cells,
reducing the ECF K decline
Buffering of ECF K through cell K uptake is impaired in
the absence of aldosterone or of insulin or of
catecholamines
Cell K exit to the ECF increases when osmolarity
increases (as in diabetes mellitus) and in metabolic
acidosis, when it is exchanged for ECF protons (H+)
When cells die, they release their very high K content
to the ECF
49. Sources of K
Banana, orange, apple, pineapple
Almond, dates, beans, potatoes
Editor's Notes
A: potassium homeostasis depends on maintenance of external and internal potassium balance. External potassium balance is determined by rate of potassium intake (100 meq/day) and rate of urinary (90 meq/day) and fecal excretion (10 meq/day). Internal potassium balance depends on distribution of potassium between muscle, bone, liver, and red blood cells (RBC) and the extracellular fluid (ECF). This distribution is regulated by several hormones and is affected by acid-base balance and tonicity of plasma. (Movement of potassium between the ECF and cells is indicated by the small arrows.) [Modified from Stanton and Giebisch (130).] B: factors affecting potassium distribution between extra- and intracellular fluid (18, 41, 110).
Summary of potassium transport along the nephron. Following filtration, potassium is extensively reabsorbed along the proximal tubule and the loop of Henle. Potassium is secreted along the initial and cortical collecting tubule. Net secretion can be replaced by net reabsorption in states of potassium depletion. Also shown are the two cell types lining the distal tubule and cortical collecting duct. PCT, proximal tubule; TAL, thick ascending limb; CCT, cortical collecting tubule; DCT, distal convoluted tubule; S, secretion; R, reabsorption; ALDO, aldosterone; ADH, antidiuretic hormone; MCD, medullary collecting duct; ICT, initial connecting tubule. [Reprinted from Giebisch and Wang (41).]