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VenousPressure

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MedClip - Estimating Jugular Venous Pressure Heywood

Estimating Jugular Venous Pressure Heywood: Using neck veins to estimate central venous pressure. Created by J Thomas Heywood, special thanks to the Weaver family  
medclip.com
over 5 years ago
Foo20151013 2023 1eqve0g?1444774030
1
89

LWW: Case Of The Month - May 2013

This month’s case is by Barbara J. Mroz, M.D. and Robin R. Preston, Ph.D., author of Lippincott’s Illustrated Reviews: .Physiology (ISBN: 9781451175677). For more information, or to purchase your copy, visit: http://tiny.cc/PrestonLIR, with 15% off using the discount code: MEDUCATION. The case below is followed by a choice of diagnostic tests. Select the one lettered selection that would be most helpful in diagnosing the patient’s condition. The Case A 54-year-old male 2 pack-per-day smoker presents to your office complaining of cough and shortness of breath (SOB). He reports chronic mild dyspnea on exertion with a daily cough productive of clear mucus. During the past week, his cough has increased in frequency and is now productive of frothy pink-tinged sputum; his dyspnea is worse and he is now short of breath sometimes even at rest. He has had difficulty breathing when lying flat in bed and has spent the past two nights sleeping upright in a recliner. On physical examination, he is a moderately obese male with a blood pressure of 180/80 mm Hg, pulse of 98, and respiratory rate of 22. His temperature is 98.6°F. He becomes winded from climbing onto the exam table. Auscultation of the lungs reveals bilateral wheezing and crackles in the lower posterior lung fields. There is pitting edema in the lower extremities extending up to the knees.  Question Which if the following tests would be most helpful in confirming the correct diagnosis? A. Spirometry B. Arterial blood gas C. Complete blood count D. B-type natriuretic peptide blood test E. Electrocardiogram Answer? The correct answer is B-type natriuretic peptide blood test. Uncomfortable breathing, or feeling short of breath, is a common medical complaint with multiple causes. When approaching a patient with dyspnea, it is helpful to remember that normal breathing requires both a respiratory system that facilitates gas exchange between blood and the atmosphere, and a cardiovascular system that transports O2 and CO¬2 between the lungs and tissues. Dysfunction in either system may cause dyspnea, and wheezing (or bronchospasm) may be present in both cardiac and pulmonary disease. In this patient, the presence of lower extremity edema and orthopnea (discomfort when lying flat) are both suggestive of congestive heart failure (CHF). Elevated blood pressure (systolic of 180) and a cough productive of frothy pink sputum may also be associated symptoms. While wheezing could also be caused by COPD (chronic obstructive pulmonary disease) in the setting of chronic tobacco use, the additional exam findings of lung crackles and edema plus systolic hypertension are all more consistent with CHF. What does the B-type natriuretic peptide blood test tell us? When the left ventricle (LV) fails to maintain cardiac output (CO) at levels required for adequate tissue perfusion, pathways are activated to increase renal fluid retention. A rising plasma volume increases LV preload and sustains CO via the Frank-Starling mechanism. Volume loading also stimulates cardiomyocytes to release atrial- (ANP) and B-type (BNP) natriuretic peptides. BNP has a longer half-life than ANP and provides a convenient marker for volume loading. Plasma BNP levels are measured using immunoassay; levels >100 pg/mL are suggestive of overload resulting in heart failure. How does heart failure cause dyspnea? Increasing venous pressure increases mean capillary hydrostatic pressure and promotes fluid filtration from the vasculature. Excess filtration from pulmonary capillaries causes fluid accumulation within the alveoli (pulmonary edema) and interferes with normal gas exchange, resulting in SOB. Physical signs and symptoms caused by high volume loading include: (1) Lung crackles, caused by fluid within alveoli (2) Orthopnea. Reclining increases pulmonary capillary hydrostatic pressure through gravitational effects, worsening dyspnea when lying flat. (3) Pitting dependent edema caused by filtration from systemic capillaries, an effect also influenced by position (causing edema in the lower legs as in our ambulatory patient or in dependent areas like the sacrum in a bedridden patient). What would an electrocardiogram show? Heart failure can result in LV hypertrophy and manifest as a left axis deviation on an electrocardiogram (ECG), but some patients in failure show a normal ECG. An ECG is not a useful diagnostic tool for dyspnea or CHF per se. Wouldn’t spirometry be more suitable for diagnosing the cause of dyspnea in a smoker? Simple spirometry will readily identify the presence of airflow limitation (obstruction) as a cause of dyspnea. It's a valuable test to perform in any smoker and can establish a diagnosis of chronic obstructive pulmonary disease (COPD) if abnormal. While this wheezing patient is an active smoker who could have airflow obstruction, the additional exam findings above point more to a diagnosis of CHF. What would an arterial blood gas show? An arterial blood gas measures arterial pH, PaCO¬2, and PaO2. While both CHF and COPD could cause derangements in the values measured, these abnormalities would not necessarily be diagnostic (e.g., a low PaO2 could be seen in both conditions, as could an elevated PaCO¬2). Would a complete blood count provide useful information? A complete blood count could prove useful if anemia is a suspected cause of dyspnea. Test result BNP was elevated (842 pg/mL), consistent with CHF. Diuretic treatment was initiated to help reduce volume overload and an afterload reducing agent was started to lower blood pressure and improve systolic function.  
Lippincott Williams & Wilkins
over 6 years ago
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Signs of shock and raised jugular venous pressure

A 38 year old white man presented to the emergency department with a three month history of progressively worsening shortness of breath. He had also experienced other vague symptoms over the same period, including muscle aches, weakness, pains associated with fatigue, and noticeable weight loss. Having previously been fit and well, he was now struggling to climb the stairs at home. The onset of symptoms coincided with an episode of food poisoning; he denied any recent travel.  
feeds.bmj.com
over 4 years ago
Www.bmj
0
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A 77 year old man with asthma and renal impairment

A 77 year old man presented after a collapse at home with a three week history of dyspnoea, malaise, and myalgia. He reported a 10 year history of hypertension, and that he had undergone a nasal polypectomy seven years earlier and had recently been diagnosed as having asthma. Prescribed drugs included candesartan 4 mg daily, enalapril 20 mg daily, beclometasone dipropionate 200 µg twice daily, and salbutamol as needed. He had not recently changed his drugs or used non-steroidal anti-inflammatory agents or herbal remedies. On examination his blood pressure was 156/88 mm Hg; temperature was 36.8°C; and he had generalised polyphonic wheeze, raised jugular venous pressure (5 cm above the sternal angle), and mild bilateral ankle oedema.  
feeds.bmj.com
over 4 years ago
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0
8

A 77 year old man with asthma and renal impairment

A 77 year old man presented after a collapse at home with a three week history of dyspnoea, malaise, and myalgia. He reported a 10 year history of hypertension, and that he had undergone a nasal polypectomy seven years earlier and had recently been diagnosed as having asthma. Prescribed drugs included candesartan 4 mg daily, enalapril 20 mg daily, beclometasone dipropionate 200 µg twice daily, and salbutamol as needed. He had not recently changed his drugs or used non-steroidal anti-inflammatory agents or herbal remedies. On examination his blood pressure was 156/88 mm Hg; temperature was 36.8°C; and he had generalised polyphonic wheeze, raised jugular venous pressure (5 cm above the sternal angle), and mild bilateral ankle oedema.  
feeds.bmj.com
over 4 years ago
Preview
0
8

A 77 year old man with asthma and renal impairment

A 77 year old man presented after a collapse at home with a three week history of dyspnoea, malaise, and myalgia. He reported a 10 year history of hypertension, and that he had undergone a nasal polypectomy seven years earlier and had recently been diagnosed as having asthma. Prescribed drugs included candesartan 4 mg daily, enalapril 20 mg daily, beclometasone dipropionate 200 µg twice daily, and salbutamol as needed. He had not recently changed his drugs or used non-steroidal anti-inflammatory agents or herbal remedies. On examination his blood pressure was 156/88 mm Hg; temperature was 36.8°C; and he had generalised polyphonic wheeze, raised jugular venous pressure (5 cm above the sternal angle), and mild bilateral ankle oedema.  
feeds.bmj.com
over 4 years ago
Www.bmj
0
10

A 77 year old man with asthma and renal impairment

A 77 year old man presented after a collapse at home with a three week history of dyspnoea, malaise, and myalgia. He reported a 10 year history of hypertension, and that he had undergone a nasal polypectomy seven years earlier and had recently been diagnosed as having asthma. Prescribed drugs included candesartan 4 mg daily, enalapril 20 mg daily, beclometasone dipropionate 200 µg twice daily, and salbutamol as needed. He had not recently changed his drugs or used non-steroidal anti-inflammatory agents or herbal remedies. On examination his blood pressure was 156/88 mm Hg; temperature was 36.8°C; and he had generalised polyphonic wheeze, raised jugular venous pressure (5 cm above the sternal angle), and mild bilateral ankle oedema.  
feeds.bmj.com
over 4 years ago
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0
12

A 77 year old man with asthma and renal impairment

A 77 year old man presented after a collapse at home with a three week history of dyspnoea, malaise, and myalgia. He reported a 10 year history of hypertension, and that he had undergone a nasal polypectomy seven years earlier and had recently been diagnosed as having asthma. Prescribed drugs included candesartan 4 mg daily, enalapril 20 mg daily, beclometasone dipropionate 200 µg twice daily, and salbutamol as needed. He had not recently changed his drugs or used non-steroidal anti-inflammatory agents or herbal remedies. On examination his blood pressure was 156/88 mm Hg; temperature was 36.8°C; and he had generalised polyphonic wheeze, raised jugular venous pressure (5 cm above the sternal angle), and mild bilateral ankle oedema.  
feeds.bmj.com
over 4 years ago
Preview
0
10

A 77 year old man with asthma and renal impairment

A 77 year old man presented after a collapse at home with a three week history of dyspnoea, malaise, and myalgia. He reported a 10 year history of hypertension, and that he had undergone a nasal polypectomy seven years earlier and had recently been diagnosed as having asthma. Prescribed drugs included candesartan 4 mg daily, enalapril 20 mg daily, beclometasone dipropionate 200 µg twice daily, and salbutamol as needed. He had not recently changed his drugs or used non-steroidal anti-inflammatory agents or herbal remedies. On examination his blood pressure was 156/88 mm Hg; temperature was 36.8°C; and he had generalised polyphonic wheeze, raised jugular venous pressure (5 cm above the sternal angle), and mild bilateral ankle oedema.  
feeds.bmj.com
over 4 years ago
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5
171

Cerebrospinal fluid

The cerebrospinal fluid (CSF) is produced from arterial blood by the choroid plexuses of the lateral and fourth ventricles by a combined process of diffusion, pinocytosis and active transfer. A small amount is also produced by ependymal cells. The choroid plexus consists of tufts of capillaries with thin fenestrated endothelial cells. These are covered by modified ependymal cells with bulbous microvilli. The total volume of CSF in the adult ranges from140 to 270 ml. The volume of the ventricles is about 25 ml. CSF is produced at a rate of 0.2 - 0.7 ml per minute or 600-700 ml per day. The circulation of CSF is aided by the pulsations of the choroid plexus and by the motion of the cilia of ependymal cells. CSF is absorbed across the arachnoid villi into the venous circulation and a significant amount probably also drains into lymphatic vessels around the cranial cavity and spinal canal. The arachnoid villi act as one-way valves between the subarachnoid space and the dural sinuses. The rate of absorption correlates with the CSF pressure. CSF acts as a cushion that protects the brain from shocks and supports the venous sinuses (primarily the superior sagittal sinus, opening when CSF pressure exceeds venous pressure). It also plays an important role in the homeostasis and metabolism of the central nervous system.  
neuropathology-web.org
about 4 years ago