SAQ 493 – Metabolic – vomiting with mixed acid-base disturbance

A previously well 55-year-old woman presents with severe vomiting for 5 days. Her observations and venous blood gas are shown below.

Observation	Result
Heart rate	110/min
Blood pressure	100/60 mmHg
Temperature	36.8 C

Variable	Result	Reference range
pH	7.23	7.35-7.45
pO2	40 mmHg
pCO2	22 mmHg	40-52
HCO3	9 mmol/L	24-32
Na	140 mmol/L	135-145
K	3.4 mmol/L	3.5-4.8
Cl	77 mmol/L	95-110

What is the primary acid-base disturbance?

(Marked out of 1.0)

/ 1

Calculate the anion gap and show your calculation.

(Marked out of 2.0)

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Is there adequate compensation? Show your calculation.

(Marked out of 2.0)

/ 2

What is the delta ratio? Show your calculation.

(Marked out of 2.0)

/ 2

What does this delta ratio indicate in this clinical setting?

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Provide a unifying explanation for these blood gas results.

(Marked out of 2.0)

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Total Score: 0 / 11

Percentage: 0%