Now relatively rare in the UK Older children have more severe disease Caused by the Morbillivirus, which is a type of paramyoxovirus This is a single stranded, enveloped RNA virus It is a highly contagious infection of the respiratory system, and can be passed on by airborne transmission, via droplets expelled in coughing, sneezing and respiration.
almostadoctor.com - free medical student revision notes
over 6 years ago
Vivid animation and real-life examples demonstrate the respiration process, including the transfer of oxygen into the bloodstream and the effect of exercise on the respiratory system.
over 6 years ago
The punctum (puncta) are tiny holes located in the eyelids near the bridge of the nose. Excess tears drain through the punctum, down the canalicular system into the lacrimal sac, then down into the nose. This explains why you get a runny nose when your eyes are watering.
over 6 years ago
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 7 years ago
How do we explain a patient having a normal finger to nose test but also having dysdiadochokinesia and romberg positive?
How do we explain a patient having a normal finger to nose test but also having dysdiadochokinesia and romberg' positive?
over 7 years ago
All tutorials I've come across teach that to scan lungs and pleura you only need to scan anterior & lateral thorax wall, each made up of 4 segments (sup ant/lat & inf ant/lat). It doesn't quite make sense to me eg when looking for consolidation which might be localized to just one segment. And I've seen case reports of findings on posterior thorax. Can anyone enligthen me about the truth here?
almost 8 years ago