2: Shock Flashcards
What is shock?
TIssue hypoperfusion (and hypoxia) due to circulatory failure
Which mean arterial pressure is required to perfuse the vital organs?
50 - 60 mm Hg
If asked quote 60 mm Hg
How do you calculate MAP?
(Systolic + 2(Diastolic)) / 3
Which group of patients require a higher MAP to perfuse their vital organs?
Those with atherosclerotic disease
What is Virchow’s triad of thrombosis?
Epithelial damage
Hypercoagulability
Stasis
Which byproduct of anaerobic respiration is produced in hypoxic tissues?
What state does this lead to?
Lactic acid
Metabolic acidosis
What effect does acidosis have on cells?
Unsuitable living conditions
Enzymes stop working, cell membranes break down
This is bad
What is mottled skin also known as?
Livedo reticularis
What does livedo reticularis look like?
Mottled skin
Areas of red, patchy skin and pale cold skin
What does widespread livedo reticularis indicate?
Shock
widespread capillary disease
Name four immediate signs of shock.
Mottled skin - livedo reticularis, clogged capillaries
Altered GCS - brain involvement
Oliguria - renal involvement
Elevated serum lactate - anaerobic respiration
Above which level of lactate is abnormal?
> 0.75
Are all shocked patients hypotensive?
No
Because of compensatory mechanisms
In terms of the variables which create a cardiac output, which one increases in response to pump failure?
Total peripheral resistance
i.e you vasoconstrict to divert blood to the heart
resulting in cold, clammy peripheries
What are some causes of pump failure?
MI
Arrhythmia
Severe valve disease
Cardiomyopathy
Drug poisoning
