acid base problems

Question 1

what leads to lactic acidosis

Answer 1

ischemia at tissues

• history of HF suggest CO problems
• impaired O2 transfer in lungs due to oedema & COPD
• hypotension gives under-perfusion of tissues

Question 2

how does a patient with lactic acidosis have hyperkalaemia

Answer 2

movement of lactate from inside cell to ECF inhibits Na/K/ATPase giving increased K outside cell

Question 3

why would a patient with low BP have elevated creatinine

Answer 3

low BP gives under-perfusion of kidneys, reducing GFR & clearance of creatinine

Question 4

cause of metabolic acidosis in hypotensive patient

Answer 4

diarrhoea and loss of bicarbonate

may also be due to ischaemia or impaired renal function

Question 5

normal anion gap in metabolic acidosis

Answer 5

indicates that the fixed acid generated is Cl-. Used to as a counter ion in her metabolic acidosis (not lactic acid or DKA)

Question 6

hypokalaemia in acidosis patient with hypovolemia

Answer 6

buffering of ECF H+ in cells results in increased extracellular K+. H+ enters cell in exchange for K+ leaving

hypovolemia also activates RAAS. Aldosterone leads to increased renal excretion of K+