53&54: Body Fluid Problems Flashcards
1
Q
Why is someone in cardiogenic shock sweaty with a high heart rate and low blood pressure?
A
Due to sympathetic activation
2
Q
If blood ____ is reduced, cardiac filling decreases and ___ receptor activity is reduced
If >10% loss of blood ____, arterial pressure falls and ____ firing is reduced
A
- Blood volume
- Cardiac receptor
- Volume
- Baroreceptor
3
Q
Why does haematocrit reduce with acute, sustained blood loss?
A
- Loss of volume and inc. vasoconstriction
- Drops pressure at capillaries
- Fluid moves into intravascular space causing dilution of plasma proteins
4
Q
Why might a patient with blood loss have low pH?
A
- Low blood flow = tissue ischaemia
- Inc. lactic acid production
- Kidney injury due to prolonged lack of blood flow
5
Q
Why does central venous pressure rise in spaceflight despite inc. loss of blood volume?
A
- Inc. central pressure bc less being forced into extremities
- Inc. atrial and venous distension causes ANP release
- Causes natriuresis and diuresis
6
Q
How do K levels change in spaceflight?
A
- Initial reduction due to reduced aldosterone
- Inc. aldosterone causes decrease
