Medicine Tips 1

Question 1

Reversible causes of cardiac arrest

Answer 1

Hs - hypoxia, hypovolaemia, hypothermia, hypo/hyperkalaemia, hydrogen ions (acidosis)
Ts - tamponade, tension pneumothorax, thrombosis (cardiac and pulmonary), toxins, trauma (commotio cordis)

Question 2

A patient with AKI needs a contrast-enhanced CT scan. Due to the increased risk of contrast-induced acute kidney injury in this patient, what do you do?

Answer 2

Infusion of IV 0.9% sodium chloride at a rate of 1 mL/kg/hour for 12 hours pre- and post- procedure

Question 3

Patient with CKD on haemodialysis. What is the most likely cause of death?

Answer 3

Ischaemic heart disease

Question 4

Treatment for cranial DI

Answer 4

Synthetic ADH (desmopressin)

Question 5

Treatment for nephrogenic DI

Answer 5

Thiazide diuretic (chlorothiazide)

Question 6

Worsening renal function with muddy brown casts

Answer 6

Acute tubular necrosis

Question 7

Features suggesting chronic renal failure instead of acute renal failure

Answer 7

Bilateral small kidneys on USS

Hypocalcaemia due to lack of vitamin D

Question 8

Routine maintenance fluid

Answer 8

25-30 ml/kg/day sodium chloride + 1 mmol/kg/day of potassium, sodium and chloride + 50-100 g/day of glucose

Question 9

5 reasons to prescribe fluids

Answer 9

Resuscitate, routine maintenance, replacement, redistribution, reassessment

Question 10

Resuscitation fluids

Answer 10

500 ml bolus of 0.9% saline over less than 15 minutes
If ongoing hypovolaemia give a further 250-500 ml bolus of 0.9% saline, then reassess with ABCDE approach
Can repeat if needed till 2000mL of fluid has been given

Question 11

Electrolyte loss from vomiting/NG tube

Answer 11

20-40 mmol Na+/ l
14 mmol K+/l
140 mmol Cl-/l
60-80 mmol H+/l

Question 12

Electrolyte loss from diarrhoea/excess stoma loss

Answer 12

30-140 mmol Na+/ l
30-70 mmol K+/l
20-80 mmol HCO3-/l

Question 13

Electrolyte loss from jejunal stoma/fistula

Answer 13

140 mmol Na+/ l
5 mmol K+/l
135 mmol Cl-/l
8 mmol HCO3-/l

Question 14

Electrolyte loss from new stoma, high stoma or fistula

Answer 14

100-140 mmol Na+/ l
4-5 mmol K+/l
75-125 mmol Cl-/l
0-30 mmol HCO3-/l

Question 15

Electrolyte loss from established stoma or low fistula

Answer 15

50-100 mmol Na+/ l
4-5 mmol K+/l
25-75 mmol Cl-/l
0-30 mmol HCO3-/l

Question 16

Electrolyte loss from dancreatic drain/fistula

Answer 16

125-138 mmol Na+/ l
8 mmol K+/l
56 mmol Cl-/l
85 mmol HCO3-/l

Question 17

Electrolyte loss from biliary drainage

Answer 17

145 mmol Na+/ l
5 mmol K+/l
105 mmol Cl-/l
30 mmol HCO3-/l

Question 18

Electrolyte loss from fever, dehydration, hyperventilation

Answer 18

Very little electrolyte content - can result in potential hypernatraemia