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Showing posts from February, 2014

Stridor

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Causes of stridor and management of acute stridor (click to enlarge):

Pedigree trees

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A basic guide to drawing pedigree trees: Basic symbols  

Hypersensitivity

Type Mediators Timing Examples Type I Hypersensitivity Allergy Exogenous antigen binding to IgE bound to Mast cells leading to degranulation Within minutes to an hour, rarely delayed onset (10-12 hours) Asthma Anaphylaxis Hayfever Type II Hypersensitivity Cytotoxic Caused by endogenous antigens which bind to cells. Antibodies IgM and IgG bind to these cells causing apoptosis Minutes to hours Autoimmune haemolytic anaemia, thrombocytopenia, Goodpasture’s syndrome Type III Hypersensitivity Immune complex (autoimmune) Caused by endogenous or exogenous antigens bound to IgG forming immune complexes which causes activation of the complement system and neutrophils causing systemic or organ specific damage. 3-8 hours SLE, Aspergillosis, Rheumatoid arthritis, Type IV Hypersensitivity ...

Heart Failure (chronic)

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Definition and demographics heart failure occurs when the heart function fails to perfuse the body adequately under normal physiological conditions. Heart failure can be divided into acute or chronic heart failure, may be caused by reduction of ejection fraction (systolic failure) or failure for the heart to fill (diastolic heart failure or heart failure with preserved ejection fraction), affect the left heart or the right heart, or both sides. It can also be divided into heart failure caused by an intrinsic disease of the heart(high output), or due to increased demands of the body (low output).  There is an increasing prevalence of heart failure patients due to the increase in older individuals and better outcomes for other cardiovascular diseases. The prevalence of heart failure is around 2-3% in the general population, with increasing incidence amongst older people. There is a slightly higher incidence amongst men compared to women, especially in the middle aged populat...