Critical Care Medicine-Renal, Electrolyte and Acid Base Disorders>>>>>Acid Base Disorders
Question 9#

An 89-year-old man with a past medical history of chronic kidney disease stage III, diabetes mellitus type II, and hypertension who is 4 days status post small bowel resection for a small bowel obstruction. He has a persistent ileus with nasogastric decompression. On the fifth day, he develops palpitations and lethargy. An ECG and laboratory parameters are shown below:


Based on this, what do you expect his urine pH value to be?

A. 4.1
B. 8.9
C. 6.0
D. 7.4
E. 3.1

Correct Answer is A


Correct Answer: A

The patient has a hypokalemic hypochloremic metabolic alkalosis caused by excessive gastrointestinal losses. This can be caused with prolonged nasogastric suctioning, vomiting, and high ileostomy ostomy output. Of note, despite the low serum chloride, the patients develop a paradoxical aciduria which is due the sodium exchange for hydrogen ion in the kidney.

The above arrows point to “U wave” which can be seen on ECGs in the presence of hypokalemia.


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  2. Aspelund G, Langer JC. Current management of hypertrophic pyloric stenosis. Semin Pediatr Surg. 2007;16(1):27-33.