Pathology EMQ template.

Name: Szamockis

Theme:

 

OPTION LIST

 

A	Metabolic acidosis	I
B	Respiratory alkalosis	J
C	Metabolic alkalosis	K
D	Respiratory acidosis	L
E	Compensated Metabolic acidosis	M
F	Compensated metabolic alkalosis	N
G	Compensated respiratory acidosis	O
H	Compensated respiratory alkalosis	P

 

 

For each scenario below, choose the most appropriate answer from the list above. Each option may be used once, more than once or not at all.

 

A patient presents with the following blood measurements:

 

1. pO2 13.2kPa, pCO2 5.8kPa, pH 7.23; Bicarbonate 17mmol/l;

 

2. pO2 6.7kPa, pCO2 10.1kPa,  pH 7.34,  Bicarbonate 42.4mmol/l;

 

3. pO2 14.3kPa, pCO2 6.5kPa, pH 7.52; Bicarbonate 37mmol/l;

 

Normal values are: 
PaO2 kPa 12.0 - 14.7
PaCO2 kPa 4.5 - 6.0
pH 7.36 - 7.44
Bicarbonate 24 – 30

 

ANSWERS

1. A

2. G

3.         C

4.

5.

 

Brief explanation: 1. This is typical of DKA, although in real life the patient would start to hyperventilate if they could, and drop the CO2, and in the process improve the pH. Answer A is correct because here, no compensation has occurred.

2. This is typical of a real patient with very bad COPD. The kidneys are compensating and trying to bring the pH (almost) to normal from what would otherwise be a severe respiratory acidosis.

3. This patient has an acute metabolic alkalosis, and perhaps has consumed several tablets of alka seltzer or sodium bicarbonate for a stomach ulcer, and finds that continuously consuming these helps his symptoms. This has become less common since the advent of drugs that control such symptoms well such as cimetidine or omeprazole.