A 41 year old man is admitted to your Emergency Department, unconscious, with the first set of blood results. The second set of blood gases are taken 1 hour later.
|
Parameter |
Initial values |
1 hour later |
Normal range |
|
pH |
7.05 |
7.35 |
7.35-7.45 |
|
PaCO2 |
34 mmHg (4.6 |
39 mmHg (5.2 kPa) |
35-45 mmHg (4.7-6.0 |
|
PaO2 |
203 mmHg (33.6 kPa) |
94 mmHg (12.5 kPa) |
75-98 mmHg (10.0- |
|
Actual bicarbonate |
9 mmol/l |
21 |
22-26 mmol/l |
|
Sodium |
137 mmol/l |
134-145 mmol/l |
|
|
Potassium |
4.2 mmol/l |
3.5-5.1 mmol/l |
|
|
Glucose |
11.2 mmol/l |
||
|
Ionised |
1.21 mmol/l |
2.15-2.55 mmol/l |
|
|
Chloride |
105 mmol/L |
95-105 mmol/L |
a. Describe the initial acid-base disturbance
b. List 3 clinical scenarios which may produce such a pattern of arterial blood gas derangement?
3.2a. The initial acid-base disturbance is a mixed metabolic and respiratory acidosis with a raised anion gap.
3.2b. Seizures
Resuscitated cardiac arrest
Near drowning
Near hanging
This question is identical to Question 15.2 from the second paper of 2009.