Answer to Question #168761 in General Chemistry for Princess Banks

Question

Case 4 (1pt)

A 47 year-old man with a history of heavy alcohol use presents with a two- day history of severe abdominal pain, nausea, and vomiting. Upon examination, his blood pressure is 90/50 and he is markedly tender in his epigastrum. His initial laboratory studies reveal a sodium of 132, chloride 92, HCO₃^- 16, creatinine 1.5, amylase 400 and lipase 250. A room air arterial blood gas is drawn and reveals pH 7.28, PaCO₂ 34, PO₂ 88, HCO ₃^- 16.

Answer 1

• The patient has a low pH (acidemia)
• The PCO₂ is low (respiratory alkalosis) and the bicarbonate is low (metabolic acidosis). The combination of the low pH and the low bicarbonate tells us that the metabolic acidosis is the primary process
• The anion gap is elevated at 24. This tells us that the patient has a primary elevated anion gap metabolic acidosis
• The respiratory alkalosis is the compensatory process
• The delta gap is 24-12 = 12. The delta delta is 12 + 17 = 29. Because the delta-delta is greater than 26, we know that the patient has a concurrent metabolic alkalosis.
• Summary: Primary elevated anion gap metabolic acidosis with respiratory compensation and a concurrent metabolic alkalosis