The document provides information on the anatomy and physiology of the brain, spinal cord, nerves, and eye. It discusses the nervous supply of the eye including sensory, autonomic, and motor innervation. Specific topics covered include the pupillary light reflex pathway, oculo-cardiac reflex, corneal reflex, eye blocks and their complications. Details are given on the blood supply and anatomy of the spinal cord. The Circle of Willis and common sites of cerebral aneurysms are described. Intracranial pressure, the Monro-Kellie doctrine, normal ICP values, and methods to measure ICP clinically are outlined.
The thyroid gland synthesizes the hormones thyroxine (T4) and triiodothyronine (T3) through a process involving iodine uptake, oxidation, and coupling reactions within thyroglobulin. T3 and T4 regulate metabolism, growth, and development. The parathyroid glands, vitamin D, and calcitonin work together to regulate calcium homeostasis by increasing or decreasing calcium absorption and resorption in the kidneys and bones. Common endocrine disorders include hypercalcemia, hypocalcemia, hyperparathyroidism, Addison's disease, Cushing's syndrome, and pheochromocytoma.
This document discusses cardiovascular physiology concepts including:
1. Normal pressures within the heart chambers and pulmonary circulation.
2. Uses of the Swan-Ganz catheter for diagnosis and treatment.
3. The Frank-Starling mechanism and factors that affect preload and contractility.
4. Hemodynamic changes that occur during the cardiac cycle, Valsalva maneuver, exercise, and respiration.
5. How the pressure-volume loop is used to assess ventricular function and how conditions like heart failure alter the loop.
This document discusses the anatomy and physiology of the cardiovascular system. It begins by describing the conduction system of the heart, including the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers. It then discusses the membrane potential of ventricular cardiac muscle cells and its relationship to electrocardiograms. Several major cardiovascular reflexes are also outlined, including the arterial baroreceptor reflex. The document provides detailed descriptions of coronary artery anatomy and blood flow regulation to the myocardium. Pathophysiology of ventricular septal defects and their management are summarized.
This document discusses anticoagulant drugs including unfractionated heparin, low molecular weight heparins, warfarin, and novel oral anticoagulants. It covers the mechanisms of action, indications, monitoring, perioperative management, and reversal of anticoagulation for bleeding events. Key points include how unfractionated heparin acts by inhibiting thrombin and other clotting factors, how warfarin inhibits vitamin K to reduce clotting factor production, and advantages of novel oral anticoagulants over warfarin in terms of pharmacokinetics and indications.
Systolic anterior motion of mitral valve - SAMgagsol
This document summarizes the hospital course of an 80-year-old female admitted with weakness and nausea. Key findings include:
- Hypertrophic cardiomyopathy with systolic anterior motion (SAM) of the mitral valve was seen on echocardiogram.
- She developed respiratory acidosis and was intubated. Atrial fibrillation was also found.
- She was treated with antibiotics for possible sepsis, amiodarone for atrial fibrillation, and beta blockers were increased to control heart rate.
- SAM occurs in HCM and involves anterior movement of the mitral valve during systole, which can be exacerbated by factors like decreased preload. It is an
This document discusses how echocardiography can be used to assess hemodynamics by measuring blood flow velocities. Doppler echocardiography is validated for measuring stroke volume, cardiac output, regurgitant volumes, and pressures in the heart by relating flow velocities to pressure gradients. Measurements of velocities across valves and in vessels can be used to estimate parameters like pulmonary artery pressures, left ventricular end diastolic pressure, and left atrial pressure through validated Doppler equations.
This document discusses techniques for evaluating left ventricular function in patients with ischemic cardiomyopathy, including multigated angiography (MUGA), myocardial perfusion scintigraphy using thallium-201 or technetium-99m tracers, gated cardiac single photon emission computed tomography (SPECT), and positron emission tomography (PET). SPECT and PET can assess myocardial perfusion, function, volumes, and viability. Segmental analysis of wall motion and calculations of ejection fraction from gated imaging provide prognostic information. The identification of viable but ischemic tissue has implications for the potential benefits of revascularization.
The thyroid gland synthesizes the hormones thyroxine (T4) and triiodothyronine (T3) through a process involving iodine uptake, oxidation, and coupling reactions within thyroglobulin. T3 and T4 regulate metabolism, growth, and development. The parathyroid glands, vitamin D, and calcitonin work together to regulate calcium homeostasis by increasing or decreasing calcium absorption and resorption in the kidneys and bones. Common endocrine disorders include hypercalcemia, hypocalcemia, hyperparathyroidism, Addison's disease, Cushing's syndrome, and pheochromocytoma.
This document discusses cardiovascular physiology concepts including:
1. Normal pressures within the heart chambers and pulmonary circulation.
2. Uses of the Swan-Ganz catheter for diagnosis and treatment.
3. The Frank-Starling mechanism and factors that affect preload and contractility.
4. Hemodynamic changes that occur during the cardiac cycle, Valsalva maneuver, exercise, and respiration.
5. How the pressure-volume loop is used to assess ventricular function and how conditions like heart failure alter the loop.
This document discusses the anatomy and physiology of the cardiovascular system. It begins by describing the conduction system of the heart, including the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers. It then discusses the membrane potential of ventricular cardiac muscle cells and its relationship to electrocardiograms. Several major cardiovascular reflexes are also outlined, including the arterial baroreceptor reflex. The document provides detailed descriptions of coronary artery anatomy and blood flow regulation to the myocardium. Pathophysiology of ventricular septal defects and their management are summarized.
This document discusses anticoagulant drugs including unfractionated heparin, low molecular weight heparins, warfarin, and novel oral anticoagulants. It covers the mechanisms of action, indications, monitoring, perioperative management, and reversal of anticoagulation for bleeding events. Key points include how unfractionated heparin acts by inhibiting thrombin and other clotting factors, how warfarin inhibits vitamin K to reduce clotting factor production, and advantages of novel oral anticoagulants over warfarin in terms of pharmacokinetics and indications.
Systolic anterior motion of mitral valve - SAMgagsol
This document summarizes the hospital course of an 80-year-old female admitted with weakness and nausea. Key findings include:
- Hypertrophic cardiomyopathy with systolic anterior motion (SAM) of the mitral valve was seen on echocardiogram.
- She developed respiratory acidosis and was intubated. Atrial fibrillation was also found.
- She was treated with antibiotics for possible sepsis, amiodarone for atrial fibrillation, and beta blockers were increased to control heart rate.
- SAM occurs in HCM and involves anterior movement of the mitral valve during systole, which can be exacerbated by factors like decreased preload. It is an
This document discusses how echocardiography can be used to assess hemodynamics by measuring blood flow velocities. Doppler echocardiography is validated for measuring stroke volume, cardiac output, regurgitant volumes, and pressures in the heart by relating flow velocities to pressure gradients. Measurements of velocities across valves and in vessels can be used to estimate parameters like pulmonary artery pressures, left ventricular end diastolic pressure, and left atrial pressure through validated Doppler equations.
This document discusses techniques for evaluating left ventricular function in patients with ischemic cardiomyopathy, including multigated angiography (MUGA), myocardial perfusion scintigraphy using thallium-201 or technetium-99m tracers, gated cardiac single photon emission computed tomography (SPECT), and positron emission tomography (PET). SPECT and PET can assess myocardial perfusion, function, volumes, and viability. Segmental analysis of wall motion and calculations of ejection fraction from gated imaging provide prognostic information. The identification of viable but ischemic tissue has implications for the potential benefits of revascularization.
The document discusses the venous anatomy of the heart, including the coronary sinus and persistent left superior vena cava (LSVC). It begins with the embryological development of the venous system. It then describes the various tributaries that drain into the coronary sinus and provides an overview of the venous drainage patterns. It discusses surgical implications of anomalies such as LSVC connection variations, coronary sinus atresia, and partial unroofing of the coronary sinus.
1) Atrial septal defects are one of the most common types of pre-tricuspid shunts and can often remain asymptomatic until later in life when they may lead to heart failure, pulmonary hypertension, or arrhythmias if left unrepaired.
2) The natural history and prognosis of atrial septal defects depends on factors like the size of the defect and age at diagnosis, with smaller defects having higher rates of spontaneous closure and repair at a younger age leading to better outcomes.
3) Device or surgical closure of atrial septal defects can successfully close the defect and improve symptoms, but the best outcomes are seen in those with less elevated pulmonary pressures and cardiac chamber enlargement prior to repair
Lung Ultrasound in Critical Care and Resuscitation: Daniel LichtensteinSMACC Conference
Daniel Lichtenstein wants to make his past your future. Join him on a journey through the history of lung ultrasound in critical care and resuscitation.
The scene is over 20 years ago in the desert of Mauritania. It is a noisy environment full of trucks and planes and motorbikes whipping up sand in a frenzy. You are attending a chest trauma and suspect a pneumothorax. However, in this chaotic environment, chest auscultation with a stethoscope is futile. Daniel describes a visual approach with a portable ultrasound in what was possibly the first extra-hospital ultrasound use.
Daniel also has a passion for in-hospital point of care. This stems from a time he “borrowed” an ultrasound machine from the radiology department and reached a critical diagnosis. His journey with lung ultrasound in critical care and resuscitation was born.
The usefulness of point of care ultrasound in critical care is far reaching. It is used for subclavian catheter insertion, searching for abdominal blood, and assessing the optic nerve or inferior vena cava. It is even used for assessing the “forbidden” area – the lungs.
The use of ultrasound is now ubiquitous; however, this has not always been the case. During its rise to prominence there was a trench war going on and its proponents had to fight claims of ridiculousness!
Daniel will highlight the utility of lung ultrasound in critical care, highlighting how proper use of the technology provides a holistic care approach to your patients. He will discuss multiple protocols he has been a part of developing and use them as an example of the philosophy of ultrasound.
The ultrasound revolution is certainly happening, but the work that made it possible happened long ago!
This document provides information on the management of cardiogenic shock. It begins with a case presentation of a 72-year-old male brought to the emergency department with sudden onset chest pain and symptoms of shock. It then defines cardiogenic shock and discusses its causes, risk factors, diagnosis, and treatment modalities. Treatment involves managing reversible causes, vasopressors, mechanical support like intra-aortic balloon pumps or ventricular assist devices, and permanent measures such as fibrinolysis, revascularization, or transplantation. The document reviews various hemodynamic support devices and their indications.
This document discusses coronary blood flow physiology, including the determinants of coronary resistance, autoregulation, microcirculation, and how blood flow is affected by exercise and the presence of coronary stenosis. It covers topics like the three resistance beds, flow-mediated dilation, metabolic mediators, neural and paracrine control, and the pushing and suction wave mechanism of diastolic flow. Measurement techniques and abnormalities in blood flow with normal coronary arteries are also briefly mentioned.
I'm afraid I don't have enough information to answer these questions. The document provided is an overview of techniques for detecting intracardiac shunts and quantifying cardiac output and shunt flow. It does not include a specific patient case. Could you please provide more details about a patient for me to reference in answering your questions?
M-mode echocardiography uses rapid sampling of a region to create sequential parallel data lines, producing continuous horizontal lines representing points of brightness. This allows visualization of motion patterns over distance and time. Measurements of structures like the mitral valve can assess morphology, movement, velocity, and timing of cardiac events. Findings include increased wall thickness, reduced valve excursion, and fluttering indicating conditions like hypertrophy, stenosis, and regurgitation.
M-mode echocardiography uses ultrasound to evaluate cardiac structures through motion over time. It can be used to assess morphology, movement, velocity and timing of valves and walls. Specific measurements are made of amplitudes, slopes, and time intervals which provide information on cardiac function. M-mode views of the mitral valve, aortic valve and left ventricle allow evaluation of values, wall motion, and calculation of ejection fraction, fractional shortening and left ventricular mass. Abnormal findings provide clues to conditions like valve disease, hypertrophy and ischemia.
ST segment elevations can occur in several conditions beyond myocardial infarction. These include early repolarization, left ventricular hypertrophy, left bundle branch block, pericarditis, myocarditis, aortic dissection, ventricular aneurysm, Prinzmetal's angina, Brugada syndrome, arrhythmogenic right ventricular cardiomyopathy, and electrocardiogram artifacts. Proper interpretation of the ST segment requires consideration of the clinical context and anatomical location of any elevations or depressions.
This document provides an overview of electrophysiological evaluation of Wolff-Parkinson-White (WPW) syndrome. It discusses the history of WPW, types of bypass tract locations, goals of the electrophysiology study including identifying accessory pathways and inducing arrhythmias. The study involves baseline measurements, pacing maneuvers like incremental atrial pacing and extrastimulus testing to identify properties of the accessory pathway. Programmed stimulation is used to induce tachycardias and entrainment mapping helps to determine the tachycardia mechanism. Radiofrequency ablation aims to eliminate conduction over the accessory pathway which is confirmed with post-ablation testing.
Wide QRS tachycardia requires differentiating between ventricular tachycardia (VT) and supraventricular tachycardia (SVT) with aberrancy. The document outlines the following approach:
1. Obtain history, physical exam, and 12-lead electrocardiogram (ECG) findings to help determine VT vs SVT. Features like AV dissociation or axis deviation favor VT.
2. Use criteria/algorithms like Wellens, Brugada, Vereckei (incorporating lead aVR) to analyze ECG morphology. A majority of criteria must be met to diagnose VT.
3. Consider electrophysiological testing like measuring His-ventricular intervals
The document discusses electrocardiogram (ECG) patterns associated with cardiac chamber enlargement, specifically right atrial enlargement (RAE) and left atrial enlargement (LAE). RAE is suggested by a tall, peaked P wave in leads II, III, AVF and a positive P wave in V1. LAE results in prolongation of the left atrial component of the P wave, increased posterior deviation of the left atrial vector, and left axis deviation of the P wave. The diagnostic accuracy of ECG findings for chamber enlargement is limited but can provide clues when correlated with imaging studies.
Echocardiographic Evaluation of LV Diastolic FunctionJunhao Koh
The document discusses methods for evaluating left ventricular diastolic function using echocardiography. It describes the four phases of diastole, parameters used to assess diastolic function including mitral inflow patterns, mitral annular tissue Doppler, pulmonary vein flow, left atrial size and the Tei index. Grades of diastolic dysfunction and approaches from ASE/EAE and Mayo Clinic are summarized. Continuous wave Doppler of aortic regurgitation is also presented as a noninvasive method to evaluate left ventricular relaxation.
Tissue Doppler echocardiography allows assessment of myocardial motion using Doppler ultrasound. It uses frequency shifts of ultrasound waves to calculate myocardial velocity, focusing on lower velocities than blood flow Doppler. There are two techniques: pulsed TDE uses a sample volume gate while color-coded TDE uses autocorrelation to display multigated velocity data superimposed on images. TDE is useful for evaluating systolic and diastolic left ventricular function by measuring velocities of the mitral annulus, and can help distinguish conditions like constrictive pericarditis from restrictive cardiomyopathy.
The Fontan procedure is a palliative surgery for patients born with certain congenital heart defects involving a single functional ventricle. It involves redirecting systemic venous blood directly to the lungs, without passing through a ventricle. While it provides improved survival and quality of life, long term complications can develop due to the unnatural circulation. Common complications include arrhythmias, protein losing enteropathy, liver disease, and pulmonary issues. Regular screening is important to monitor for these complications.
This document discusses various parameters used to evaluate cardiac structure and function using echocardiography. It describes parameters such as ejection fraction, mitral inflow patterns, pulmonary venous flow, tissue Doppler imaging, and color M-mode measurements that are used to assess global and regional left ventricular function as well as diastolic function. The parameters are grouped into categories of ventricular structure and systolic function, diastolic function evaluation, and stages of diastolic dysfunction. Normal ranges for various measurements are also provided.
This document discusses various types of artifacts that can occur in echocardiography and their causes. It describes artifacts related to ultrasound properties like reflection, refraction, scattering, attenuation and beam width. Common artifacts include reverberation between two reflective surfaces, ring down from gas bubbles, shadowing from highly attenuating structures, mirror images from multiple reflections, and refraction artifacts from structures acting as lenses. Side lobe and grating lobe artifacts result from secondary beams around the main ultrasound beam. Near field clutter and blooming/color bleed can obscure structures. Pseudoflow shows motion of non-blood fluids. Twinkling artifacts can mimic abnormal flow near reflective surfaces. Figure of 8 artifacts can occur around intracardiac devices
The document discusses various peripheral nerve blocks including:
- Cervical plexus block which targets nerves arising from C1-C4 including the lesser occipital nerve, greater auricular nerve, and supraclavicular nerve.
- Superficial and deep cervical plexus blocks are used for neck surgeries and procedures. The superficial block targets cutaneous branches while the deep block targets the paravertebral region from C2-C4.
- Stellate ganglion block provides sympathetic blockade for chronic pain syndromes and is performed at the C6 level, targeting the stellate ganglion. Complications include Horner's syndrome and injury to nearby structures.
This document provides details on performing brachial plexus blocks using various approaches including interscalene, supraclavicular, infraclavicular, and ultrasound-guided. The interscalene approach blocks the brachial plexus between the anterior and middle scalene muscles while the supraclavicular approach blocks the plexus above the clavicle and the infraclavicular approach blocks below the clavicle. Proper patient positioning, identification of anatomical landmarks, selection of appropriate equipment, drugs and dosages, and stimulation techniques are described for each approach. Potential complications are also outlined.
The document discusses the venous anatomy of the heart, including the coronary sinus and persistent left superior vena cava (LSVC). It begins with the embryological development of the venous system. It then describes the various tributaries that drain into the coronary sinus and provides an overview of the venous drainage patterns. It discusses surgical implications of anomalies such as LSVC connection variations, coronary sinus atresia, and partial unroofing of the coronary sinus.
1) Atrial septal defects are one of the most common types of pre-tricuspid shunts and can often remain asymptomatic until later in life when they may lead to heart failure, pulmonary hypertension, or arrhythmias if left unrepaired.
2) The natural history and prognosis of atrial septal defects depends on factors like the size of the defect and age at diagnosis, with smaller defects having higher rates of spontaneous closure and repair at a younger age leading to better outcomes.
3) Device or surgical closure of atrial septal defects can successfully close the defect and improve symptoms, but the best outcomes are seen in those with less elevated pulmonary pressures and cardiac chamber enlargement prior to repair
Lung Ultrasound in Critical Care and Resuscitation: Daniel LichtensteinSMACC Conference
Daniel Lichtenstein wants to make his past your future. Join him on a journey through the history of lung ultrasound in critical care and resuscitation.
The scene is over 20 years ago in the desert of Mauritania. It is a noisy environment full of trucks and planes and motorbikes whipping up sand in a frenzy. You are attending a chest trauma and suspect a pneumothorax. However, in this chaotic environment, chest auscultation with a stethoscope is futile. Daniel describes a visual approach with a portable ultrasound in what was possibly the first extra-hospital ultrasound use.
Daniel also has a passion for in-hospital point of care. This stems from a time he “borrowed” an ultrasound machine from the radiology department and reached a critical diagnosis. His journey with lung ultrasound in critical care and resuscitation was born.
The usefulness of point of care ultrasound in critical care is far reaching. It is used for subclavian catheter insertion, searching for abdominal blood, and assessing the optic nerve or inferior vena cava. It is even used for assessing the “forbidden” area – the lungs.
The use of ultrasound is now ubiquitous; however, this has not always been the case. During its rise to prominence there was a trench war going on and its proponents had to fight claims of ridiculousness!
Daniel will highlight the utility of lung ultrasound in critical care, highlighting how proper use of the technology provides a holistic care approach to your patients. He will discuss multiple protocols he has been a part of developing and use them as an example of the philosophy of ultrasound.
The ultrasound revolution is certainly happening, but the work that made it possible happened long ago!
This document provides information on the management of cardiogenic shock. It begins with a case presentation of a 72-year-old male brought to the emergency department with sudden onset chest pain and symptoms of shock. It then defines cardiogenic shock and discusses its causes, risk factors, diagnosis, and treatment modalities. Treatment involves managing reversible causes, vasopressors, mechanical support like intra-aortic balloon pumps or ventricular assist devices, and permanent measures such as fibrinolysis, revascularization, or transplantation. The document reviews various hemodynamic support devices and their indications.
This document discusses coronary blood flow physiology, including the determinants of coronary resistance, autoregulation, microcirculation, and how blood flow is affected by exercise and the presence of coronary stenosis. It covers topics like the three resistance beds, flow-mediated dilation, metabolic mediators, neural and paracrine control, and the pushing and suction wave mechanism of diastolic flow. Measurement techniques and abnormalities in blood flow with normal coronary arteries are also briefly mentioned.
I'm afraid I don't have enough information to answer these questions. The document provided is an overview of techniques for detecting intracardiac shunts and quantifying cardiac output and shunt flow. It does not include a specific patient case. Could you please provide more details about a patient for me to reference in answering your questions?
M-mode echocardiography uses rapid sampling of a region to create sequential parallel data lines, producing continuous horizontal lines representing points of brightness. This allows visualization of motion patterns over distance and time. Measurements of structures like the mitral valve can assess morphology, movement, velocity, and timing of cardiac events. Findings include increased wall thickness, reduced valve excursion, and fluttering indicating conditions like hypertrophy, stenosis, and regurgitation.
M-mode echocardiography uses ultrasound to evaluate cardiac structures through motion over time. It can be used to assess morphology, movement, velocity and timing of valves and walls. Specific measurements are made of amplitudes, slopes, and time intervals which provide information on cardiac function. M-mode views of the mitral valve, aortic valve and left ventricle allow evaluation of values, wall motion, and calculation of ejection fraction, fractional shortening and left ventricular mass. Abnormal findings provide clues to conditions like valve disease, hypertrophy and ischemia.
ST segment elevations can occur in several conditions beyond myocardial infarction. These include early repolarization, left ventricular hypertrophy, left bundle branch block, pericarditis, myocarditis, aortic dissection, ventricular aneurysm, Prinzmetal's angina, Brugada syndrome, arrhythmogenic right ventricular cardiomyopathy, and electrocardiogram artifacts. Proper interpretation of the ST segment requires consideration of the clinical context and anatomical location of any elevations or depressions.
This document provides an overview of electrophysiological evaluation of Wolff-Parkinson-White (WPW) syndrome. It discusses the history of WPW, types of bypass tract locations, goals of the electrophysiology study including identifying accessory pathways and inducing arrhythmias. The study involves baseline measurements, pacing maneuvers like incremental atrial pacing and extrastimulus testing to identify properties of the accessory pathway. Programmed stimulation is used to induce tachycardias and entrainment mapping helps to determine the tachycardia mechanism. Radiofrequency ablation aims to eliminate conduction over the accessory pathway which is confirmed with post-ablation testing.
Wide QRS tachycardia requires differentiating between ventricular tachycardia (VT) and supraventricular tachycardia (SVT) with aberrancy. The document outlines the following approach:
1. Obtain history, physical exam, and 12-lead electrocardiogram (ECG) findings to help determine VT vs SVT. Features like AV dissociation or axis deviation favor VT.
2. Use criteria/algorithms like Wellens, Brugada, Vereckei (incorporating lead aVR) to analyze ECG morphology. A majority of criteria must be met to diagnose VT.
3. Consider electrophysiological testing like measuring His-ventricular intervals
The document discusses electrocardiogram (ECG) patterns associated with cardiac chamber enlargement, specifically right atrial enlargement (RAE) and left atrial enlargement (LAE). RAE is suggested by a tall, peaked P wave in leads II, III, AVF and a positive P wave in V1. LAE results in prolongation of the left atrial component of the P wave, increased posterior deviation of the left atrial vector, and left axis deviation of the P wave. The diagnostic accuracy of ECG findings for chamber enlargement is limited but can provide clues when correlated with imaging studies.
Echocardiographic Evaluation of LV Diastolic FunctionJunhao Koh
The document discusses methods for evaluating left ventricular diastolic function using echocardiography. It describes the four phases of diastole, parameters used to assess diastolic function including mitral inflow patterns, mitral annular tissue Doppler, pulmonary vein flow, left atrial size and the Tei index. Grades of diastolic dysfunction and approaches from ASE/EAE and Mayo Clinic are summarized. Continuous wave Doppler of aortic regurgitation is also presented as a noninvasive method to evaluate left ventricular relaxation.
Tissue Doppler echocardiography allows assessment of myocardial motion using Doppler ultrasound. It uses frequency shifts of ultrasound waves to calculate myocardial velocity, focusing on lower velocities than blood flow Doppler. There are two techniques: pulsed TDE uses a sample volume gate while color-coded TDE uses autocorrelation to display multigated velocity data superimposed on images. TDE is useful for evaluating systolic and diastolic left ventricular function by measuring velocities of the mitral annulus, and can help distinguish conditions like constrictive pericarditis from restrictive cardiomyopathy.
The Fontan procedure is a palliative surgery for patients born with certain congenital heart defects involving a single functional ventricle. It involves redirecting systemic venous blood directly to the lungs, without passing through a ventricle. While it provides improved survival and quality of life, long term complications can develop due to the unnatural circulation. Common complications include arrhythmias, protein losing enteropathy, liver disease, and pulmonary issues. Regular screening is important to monitor for these complications.
This document discusses various parameters used to evaluate cardiac structure and function using echocardiography. It describes parameters such as ejection fraction, mitral inflow patterns, pulmonary venous flow, tissue Doppler imaging, and color M-mode measurements that are used to assess global and regional left ventricular function as well as diastolic function. The parameters are grouped into categories of ventricular structure and systolic function, diastolic function evaluation, and stages of diastolic dysfunction. Normal ranges for various measurements are also provided.
This document discusses various types of artifacts that can occur in echocardiography and their causes. It describes artifacts related to ultrasound properties like reflection, refraction, scattering, attenuation and beam width. Common artifacts include reverberation between two reflective surfaces, ring down from gas bubbles, shadowing from highly attenuating structures, mirror images from multiple reflections, and refraction artifacts from structures acting as lenses. Side lobe and grating lobe artifacts result from secondary beams around the main ultrasound beam. Near field clutter and blooming/color bleed can obscure structures. Pseudoflow shows motion of non-blood fluids. Twinkling artifacts can mimic abnormal flow near reflective surfaces. Figure of 8 artifacts can occur around intracardiac devices
The document discusses various peripheral nerve blocks including:
- Cervical plexus block which targets nerves arising from C1-C4 including the lesser occipital nerve, greater auricular nerve, and supraclavicular nerve.
- Superficial and deep cervical plexus blocks are used for neck surgeries and procedures. The superficial block targets cutaneous branches while the deep block targets the paravertebral region from C2-C4.
- Stellate ganglion block provides sympathetic blockade for chronic pain syndromes and is performed at the C6 level, targeting the stellate ganglion. Complications include Horner's syndrome and injury to nearby structures.
This document provides details on performing brachial plexus blocks using various approaches including interscalene, supraclavicular, infraclavicular, and ultrasound-guided. The interscalene approach blocks the brachial plexus between the anterior and middle scalene muscles while the supraclavicular approach blocks the plexus above the clavicle and the infraclavicular approach blocks below the clavicle. Proper patient positioning, identification of anatomical landmarks, selection of appropriate equipment, drugs and dosages, and stimulation techniques are described for each approach. Potential complications are also outlined.
The key arteries supplying the visual pathway include the internal carotid artery, posterior cerebral artery, anterior cerebral artery, ophthalmic artery, and posterior ciliary arteries. The central retinal artery supplies the retina. The optic nerve receives blood supply from the posterior ciliary arteries and branches of the ophthalmic artery. The optic chiasm, tract, lateral geniculate body, and visual cortex are supplied by branches of the internal carotid, anterior cerebral, and posterior cerebral arteries. Venous drainage is primarily through the central retinal vein, ophthalmic veins, basal veins and internal cerebral veins.
Anatomy of visual pathway and its lesions.Ruchi Pherwani
1) The visual pathway begins with photoreceptors in the retina which transmit visual information via the optic nerve and optic chiasm to the lateral geniculate nucleus. It then continues via the optic radiations to the primary visual cortex.
2) Lesions along the visual pathway can cause different types of visual field defects, including complete blindness from optic nerve lesions, bitemporal hemianopia from chiasmal lesions, and homonymous hemianopia from lesions of the optic tract or beyond.
3) The document discusses the anatomy and blood supply of structures in the visual pathway like the optic nerve, chiasm, tract, lateral geniculate nucleus and visual cortex. It also describes various causes and characteristics
Blood supplement of the brain and clinical significanceAli Amr
The document discusses the arteries that supply blood to the brain. It describes the internal carotid artery and vertebral artery as the two major arteries, and details their anatomy and branches. It also discusses the basilar artery and Circle of Willis, which connects the anterior and posterior circulations. Specific vascular territories within the brain are outlined. Clinical syndromes that can result from occlusions or lesions of different brain arteries are summarized.
Head injuries most commonly occur in individuals aged 15-24 from vehicular accidents or falls in those over 75. The brain is surrounded by meninges including the dura, arachnoid and pia mater. Increased intracranial pressure can decrease cerebral perfusion and cause neurological deterioration, so monitoring and medical or surgical interventions aim to reduce pressure and maintain blood flow to the brain.
Stellate ganglion block is useful to denervate sympathetic component involved in upper limb,head and neck disease conditions.
Careful evaluation of sympathetic involvement in disease process should be done before deciding to perform block.
Blocking agent type, dose and subsequent blocks should be decided on the basis of response to primary block.
After even successful stellate ganglion block patient should be monitored for side effects.
imaging and anatomy of blood supply of brainSunil Kumar
The summary provides an overview of the arterial supply of the brain in 3 sentences:
The brain receives its arterial blood supply from the internal carotid and vertebral arteries. The internal carotid arteries give rise to branches that supply the anterior circulation including the anterior cerebral artery and middle cerebral artery. These arteries anastomose at the circle of Willis and give off numerous smaller branches to perfuse the brain.
The vitreous body pushes the retina into place. If it shrinks due to dehydration, the retina can detach from the eye wall, damaging vision. The optic disc is a blind spot where the optic nerve and blood vessels exit the retina. The macula lutea contains the highest concentration of cones, providing sharp central vision. Fibers from the nasal retina cross at the optic chiasm, while temporal fibers remain uncrossed. The lateral geniculate body relays visual information to the visual cortex.
Indian Dental Academy: will be one of the most relevant and exciting training center with best faculty and flexible training programs for dental professionals who wish to advance in their dental practice,Offers certified courses in Dental implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic Dentistry, Periodontics and General Dentistry.
1. The document reviews anatomy of the orbit and surrounding structures relevant to ophthalmic anesthesia. It describes nerves, muscles, vasculature and layers within the orbit.
2. Various local anesthetic agents and their properties are discussed. Common techniques for ophthalmic anesthesia including topical, subconjunctival, intracameral, peribulbar, retrobulbar, and facial nerve blocks are explained.
3. Risks associated with different techniques like retrobulbar hemorrhage, globe perforation, and brainstem anesthesia are outlined. The document provides an overview of orbital anatomy and ophthalmic anesthesia techniques and considerations.
This document describes the anatomy of the neck relevant to neck dissection surgery. It outlines the boundaries of the neck, key muscles and structures like the platysma, sternocleidomastoid, trapezius and vessels. It discusses the lymph node levels and types of neck dissection surgeries like radical and selective dissections. The document provides details of the surgical approach including skin incisions and dissection of structures to completely remove lymph nodes while preserving nearby nerves and vessels.
This document discusses the anatomy and physiology of the ocular circulation. It notes that the eye has two distinct vascular systems: the retinal and uveal systems. The ophthalmic artery, a branch of the internal carotid, gives rise to these systems. It describes the branches of the ophthalmic artery that contribute to the ocular circulation, including the central retinal artery and posterior ciliary arteries. It also details the unique structure and branching patterns of arteries, capillaries, and veins that make up the retinal and uveal circulations.
Complete Description about Spinal anesthesia.
Topics which these slides cover are:
History
Anatomy
Blood supply of spinal cord
Indications and contraindications
Position
Procedure
Technique
Spinal needles
Factors affecting block height
Testing of block
Drugs of anesthesia
Complications
Peripheral nerve blocks are gaining popularity for pain management due to advantages like less nausea, hemodynamic stability, and ability to perform surgery in patients with cardiovascular or bleeding risks. Specific nerve blocks include interscalene, supraclavicular, infraclavicular, axillary, and others. Ultrasound is often used to identify nerves and nearby structures before injection of local anesthetic, allowing effective pain relief with fewer side effects compared to general or epidural anesthesia. Proper technique and understanding of anatomy are required to perform safe and effective peripheral nerve blocks.
1. The brain receives blood supply from the internal carotid arteries and vertebral arteries, whose branches anastomose to form the circle of Willis at the base of the brain.
2. The internal carotid artery enters the skull through the carotid canal and gives off branches including the anterior cerebral artery, middle cerebral artery, and posterior communicating artery.
3. Occlusion of the internal carotid or its major branches can cause symptoms such as hemiparesis, aphasia, or visual field defects depending on the location of occlusion.
The document discusses cranial nerves III (oculomotor), IV (trochlear), and VI (abducens). It describes the anatomy and nuclei of each nerve, their paths through the brainstem and skull base, the eye muscles they innervate and their actions. It also reviews common clinical lesions that can cause palsies of each nerve, including at the nuclei, brainstem, cavernous sinus, orbital apex, and isolated palsies. Syndromes involving combinations of cranial nerve palsies are also summarized.
The document discusses cranial nerves III (oculomotor), IV (trochlear), and VI (abducens). It describes the anatomy and nuclei of each nerve, their paths through the brain and orbit, the muscles they innervate, and examples of clinical lesions that can occur. Cranial nerve III has motor functions including eye movement and parasympathetic innervation. Cranial nerve IV is the only crossed nerve and innervates the superior oblique muscle. Cranial nerve VI innervates the lateral rectus muscle and is responsible for eye abduction.
This document discusses anesthesia considerations for eye surgery. It begins by describing the anatomy of the eye and its nerve supply. It then discusses risks like the oculocardiac reflex and increases in intraocular pressure. Common ophthalmic drugs are outlined along with their systemic effects. The document reviews preoperative evaluation, various regional anesthesia techniques like facial nerve blocks and retrobulbar blocks, topical anesthesia, and general anesthesia. It concludes with considerations for pediatric ophthalmic procedures.
Similar to Anatomy & physiology of Brain,Spinl cord Nerve,Eye.pptx (20)
This document provides guidance on anesthesia for living donor renal transplantation. It discusses preoperative assessment of patients with chronic kidney disease, including comorbidities and renal replacement therapy. Intraoperative care aims to maintain normotension, normothermia, and adequate intravascular volume to optimize graft function. Measures like dopamine infusions, furosemide boluses, and mannitol can improve renal blood flow. Postoperatively, patients are monitored in the PACU or ICU for complications like bleeding or metabolic dysfunction, treating hypotension and monitoring pressures and output. Pain management emphasizes avoiding NSAIDs that could reduce renal function.
This document discusses two diuretic drugs: Mannitol and Spironolactone. Mannitol is an osmotic diuretic that works by not being reabsorbed and increasing the osmolality of the kidney filtrate, causing water to be excreted. It can be used to treat increased intracranial pressure. Spironolactone is an aldosterone antagonist that works in the distal convoluted tubule and collecting ducts by competitively blocking aldosterone and its stimulation of sodium reabsorption in exchange for potassium. It has uses in treating ascites, nephrotic syndrome, and primary hyperaldosteronism.
This document discusses the classification and mechanisms of action of various antiarrhythmic drugs. It focuses on sodium channel blockers, beta-blockers, potassium channel blockers, and calcium channel blockers. Specific drugs discussed in more detail include amiodarone and digoxin. For each, the mechanisms of action, kinetics, uses, dosing, toxicity, and side effects are summarized. Digibind is also discussed as an antidote for digoxin toxicity.
This document discusses intraoperative critical incidents, including possible causes and management of low heart rate and blood pressure during surgery, as well as a case of cardiac arrest during spinal anesthesia. It provides guidance on post-resuscitation care, investigating suspected anaphylaxis, dealing with reports of patient awareness during surgery, and monitoring depth of anesthesia to help prevent awareness.
This document discusses adrenergic receptors and non-anesthetic drugs that act on them. It describes the types and locations of beta-1 and beta-2 receptors, and how beta blockers work by selectively binding to these receptors to decrease heart rate, contractility, and conduction times. It also discusses the pharmacokinetics of beta blockers, including their absorption, distribution, metabolism and excretion, which depends on lipid solubility. Finally, it outlines several types of second messengers involved in G protein-coupled receptor signaling, such as cAMP, cGMP, IP3, DAG and calcium ions.
This document discusses non-anesthetic drugs, focusing on antidepressant agents. It describes the main classes of antidepressants including SSRIs, TCAs, and MAOIs. It provides details on the mechanisms of action, pharmacokinetics, toxicity features, and management of TCA overdose and serotonin syndrome.
This document discusses opioids including their classification, mechanism of action, receptors, metabolism, pharmacokinetics, and management of opioid-dependent patients. It covers specific opioids like morphine, diamorphine, fentanyl, alfentanyl, remifentanyl, oxycodone, and codeine. Transdermal delivery systems and concerns using remifentanyl PCA in labor are also mentioned. The final section discusses anesthetic management and concerns for an addict pregnant female undergoing cesarean section.
Local anesthetics work by blocking sodium channels in nerve cell membranes. They exist in both ionized and unionized forms, and a higher pKa means slower onset of action as the drug is less likely to be in the unionized form needed to pass through membranes. Factors like lipid solubility and protein binding determine a drug's potency and duration. Ropivacaine has a sensory blockade similar to bupivacaine but shorter motor blockade, and its duration can be increased through alkalinization. Local anesthetic toxicity is treated by recognizing the symptoms and providing immediate care, treatment, and follow-up which may include Intralipid infusion which is thought to work by sequestering lipophilic drugs.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
Executive Directors Chat Leveraging AI for Diversity, Equity, and InclusionTechSoup
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
हिंदी वर्णमाला पीपीटी, hindi alphabet PPT presentation, hindi varnamala PPT, Hindi Varnamala pdf, हिंदी स्वर, हिंदी व्यंजन, sikhiye hindi varnmala, dr. mulla adam ali, hindi language and literature, hindi alphabet with drawing, hindi alphabet pdf, hindi varnamala for childrens, hindi language, hindi varnamala practice for kids, https://www.drmullaadamali.com
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
3. Nerve Supply of the Eye
Sensory
Optic nerve receives light input from the retina
Ophthalmic (V1) branch of trigeminal nerve
Maxillary (V2) branch of trigeminal nerve
Autonomic
• Sympathetic – pupillary dilatation By long and short ciliary nerves
• Parasympathetic – pupillary constriction By short postganglionic ciliary nerve
Motor (3LR6SO4)
• Lateral rectus (abduction) – abducens nerve (CN VI)
• Superior oblique– trochlear nerve (CN IV)
• Others– oculomotor nerve (CN III
4. Parasympathetic supply
►The preganglionic fibres originate in the
Edinger-Westphal nucleus in the brain stem and
then pass in the 3rd CN to the ciliary ganglion.
► The postganglionic fibres then enter the eye via
the short ciliary nerve and innervate the ciliary
muscles.
► Activation of the parasympathetic pathway
constricts the pupil (miosis)
5. Sympathetic supply
►This originates in the hypothalamus, and passes
to the superior cervical ganglion via the dorsal
roots.
►From The superior cervical ganglion , the fibres
synapse and project cranially and innervate the
eye either via the short ciliary nerve, long ciliary
nerve or directly into the orbit then innervate the
radial fibres of the iris.
►Activation of the sympathetic pathway dilates
the pupil (mydriasis).
6. Oculo-cardiac reflex
This occurs during ophthalmic procedures especially seen in children and in squint surgery. It is
parasympathetically activated causing profound bradycardia and even sinus arrest due to
traction on the extraocular muscles or compression of the globe.
The afferent pathway is via the trigeminal nerve and the efferent pathway is via the vagus
nerve.
Treated by:
removal of initial stimulus
anticholinergics
deepening of anesthesia
Local anesthetics used prior to the procedure may reduce this phenomenon
7. Pupillary light reflex
Light is shone into the eye which enters the pupil and stimulates the
retina.
Afferent limb:
retinal ganglion cells transmit the light signal to the optic nerve
The optic nerve enters the optic chiasma where the nasal retinal
fibres cross to contralateral optic tract and the temporal retinal fibres
stay in the ipsilateral optic tract.
Centre:
fibres from the optic tracts project and synapse in the pretectal
nucleI which project fibres to the EWN bilaterally .
Efferent limb:
the EWN projects preganglionic parasympathetic fibres, which travel
along the oculomotor nerve and then synapse with the ciliary
ganglion, which sends postganglionic parasympathetic fibres (short
ciliary nerves) to innervate the sphincter muscle of the pupils
resulting in pupillary constriction.
9. Eye blocks
Indications
Cataract surgery ,vitreoretinal surgery, strabismus correction.
Drugs used
Local anaesthetic: 2% lignocaine and/or bupivacaine 0.5%
Hyaluronidase: to increase the effectiveness of the block by enabling the spread of local
anaesthetic through the tissues.
10. Eye blocks
Sub-Tenon’s block (episcleral injection)
Peribulbar block (extraconal injection)
Retrobulbar block (intraconal injection)
Ask patient to look up and out.
Apply topical local anaesthetic and antiseptic.
11. Sub-Tenon’s block (episcleral injection)
-Using special forceps (Moorfield’s) to expose a
thick fold of conjunctiva in the inferonasal quadrant
-make a small 1–2 mm cut with round tip scissors
Slowly advance a blunt, 25 mm 19G sub-Tenon’s
cannula, following the curvature of the globe
posteriorly.
-Confirm negative aspiration before injecting 2–5 ml
surgical time.
12. Peribulbar block (extraconal injection)
The point of injection is at the junction of the lateral one third
and medial two-thirds of the eye.
-A 25G 16 mm needle is inserted through the conjunctiva or
percutaneously with bevel facing up and advanced aiming at
an inferotemporal angle parallel to the floor of the orbit.
- The needle tip should remain extraconal and should not be
advanced further than the posterior border of the globe.
-Inject 6–12 ml of local anaesthetic after confirming negative
aspiration.
-Apply pressure to the eye to promote spread
13. Retrobulbar block (intraconal injection)
-A 24 mm 25G needle is inserted at the same insertion point as
above either through the conjunctival fold or percutaneously
through the lower eyelid.
-The needle is advanced parallel to floor of orbit.
-At about 10–15 mm, it is redirected medially and upwards to
enter the muscle cone and inject 3–5 ml local anaesthetic after
negative aspiration.
• Apply pressure to the eye to promote spread.
16. Blood supply of the spinal cord.
ASA:
single artery formed at the foramen magnum by the union of each vertebral artery
supplying the anterior two-thirds of the spinal cord in front of the posterior grey column.
PSA:
derived from the posterior inferior cerebellar artery (PICA) or vertebral artery
Pial arterial plexus:
surface vessels branch from the ASA and PSA forming an anastomosing network that penetrates and
supplies the outer portion of the spinal cord.
Segmental branches:
segmental or radicular branches arise from vertebral, deep cervical, costocervical, aorta and the pelvic
vessels.
Arteria radicularis magna, or the artery of Adamkiewicz
arises from the thoracolumbar part of the aorta, usually on the left, and enters the spinal cord at the level
of L1 and supplies the lower thoracic and upper lumbar parts of the cord.
17. A 57-year-old man having a total hip arthroplasty under spinal
anaesthesia. 8hrs Postoperatively, sensory loss at level of T10
post
DD?
ASA syndrome
Cauda equina syndrome
Transverse myelitis
Guillain-Barré syndrome
Multiple sclerosis
Spinal epidural abscess
Epidural hematoma
Disk herniation
Meningitis/encephalitis
18. part of the spinal cord acts as a watershed zone
Watershed effect occurs when two streams of blood flowing in opposite directions meet.
This happens where the radicular artery unites with the ASA, where blood courses upward and
downward from the entry point, thus leaving a watershed region between the adjacent radicular areas
where blood flows in neither direction.
The watershed effect is maximum in the mid-thoracic area due to the greater distance between the
radicular arteries.
19. ASA syndrome
ASA syndrome—problems in the anterior spinal artery territory resulting in critical ischaemia of the
anterior part of the spinal cord. The characteristic findings are
Motor Loss of motor function bilaterally below the level of lesion due to the involvement of
corticospinal tracts
Sensory Loss of spinothalamic tracts resulting in bilateral thermoanaesthesia But intact light touch,
vibration, and proprioception due to preservation of posterior columns
Autonomic
Sexual dysfunction; loss of bladder and bowel function due to the effect on descending autonomic tract
20. Epidural space
The epidural space surrounds the dura from the foramen magnum to S2/S3 where the dural sac ends.
Boundaries
• Superior: foramen magnum
• Inferior: sacral hiatus and sacrococcygeal membrane
• Anterior: posterior longitudinal ligament, vertebral bodies and intervertebral discs
• Posterior: vertebral spines, interlaminar spaces filled with ligamentum flavum
• Lateral: pedicles, intervertebral foramina
Contents
Dura, spinal nerve roots, vessels, venous plexus of Batson, connective tissue, lymphatics and fat
22. The Circle of Willis
-This can be divided into the anterior and posterior cerebral
circulations that are connected via the anterior and
posterior communicating arteries forming the Circle of
Willis.
-Two thirds of the cerebral arterial supply is via the internal
carotid arteries and one third via the vertebral arteries
23. The Circle of Willis
Carotid system
• Origin The right common carotid artery arises from a bifurcation of the brachiocephalic trunk
(the right subclavian artery is the other branch).
The left common carotid artery branches directly from the arch of aorta.
The left and right common carotid arteries ascend up the neck, lateral to the trachea and the
oesophagus. They do not give off any branches in the neck
24. The Circle of Willis
Vertebrobasilar system
• Origin The right and left vertebral arteries arise from the subclavian arteries
• They enter the cranial cavity via the foramen magnum, and converge and give rise to the basilar
arteries, which supply the brain.
25.
26. Aneurysms commonly occur at the sites of bifurcations, around the Circle of Willis.
40% at anterior communicating artery and ACA
30% at MCA branches Head and Neck 47
27. The Monro–Kellie doctrine
►The skull is a rigid box containing
brain tissue (80%),
blood (12%)
CSF (8%).
►The volume of the box is constant, so an
increase in volume of any one of the intracranial
constituents must be accompanied by a parallel
reduction in the volume of another constituent
if ICP is to remain constant
28. Normal intracranial pressure
Normal Around 10 mmHg or less
Sustained pressure of >15 mmHg is termed ‘intracranial hypertension’
Areas of focal ischaemia if ICP > 20
Global ischaemia if ICP > 50
Treatment usually considered if ICP > 20
29. The indications for ICP monitoring following head injury
Some suggested indications include:
GCS<8 with an abnormal CT scan
Normal CT scan but two or more of the following factors
Age >40
Hypotension
Unilateral posturing
Bilateral posturing
30. measure intracranial pressure clinically
There are four methods commonly used via the skull and a lumbar approach via a CSF catheter.
1) Epidural catheter Strain gauge transducer at tip or fibre-optically supplied light reflecting off a
pressure-sensitive membrane
2) Subdural bolt or catheter Prone to blocking and leak but less risk of infection than ventricular
catheter
3) Ventricular catheter Gold standard, accurate, CSF can be drained but risk of infection
4) Intraparenchymal catheter Light reflecting pressure-sensitive membrane
►The appropriate monitor will display the ICP and a waveform
31. Lundberg waves
A-waves Sustained pressure waves (60–80 mmHg) every
5–20 minutes
Life-threatening and represent cerebral vasodilatation in
response to ↓ CPP. Need urgent treatment.
B-waves Small and short lasting waves (10–20 mmHg)
every 30–120 seconds. Also reflect intracranial non–
compliance but to a lesser degree
C-waves Small oscillations (0–10 mmHg), reflect changes
in systemic arterial pressure
33. Pain receptors
Pain receptors are unmyelinated nerve endings that are abundant in skin and musculoskeletal
tissue, and that respond to thermal, mechanical and chemical stimuli.
They are classified according to their sensitivity to the type of stimulus:
> Unimodal (thermo-mechanoreceptors) respond to pinprick and sudden heat.
> Polymodal respond to pressure, heat, cold, chemicals and tissue damage.
34. types of nerve fibres involved in pain pathway
> Three main types of fibres relay sensory inputs from the periphery
> The cell bodies of all three fibres lie in the dorsal root ganglia.
> The fibres terminate in the dorsal horn of the spinal cord, where they synapse with secondary
afferent neurones in Rexed’s laminae.