A rare cause of severe metabolic acidosis: Presurgical fasting

Objectives: To discuss a clinical case and a non-systematic literature review on severe metabolic acidosis due to pre-surgical fasting, its incidence, etiology, and pathophysiology. Materials and methods: Discussion of a case of a patient with fasting-induced severe metabolic acidosis during a laparoscopic cholecystectomy, its management and outcomes. The Ethics Committee of our institution approved the case discussion. The literature search included Pub Med, Scielo and Bireme. Results: Fasting-induced metabolic acidosis is underdiagnosed and is related to the search for an alternate energy source in the absence of glucose and glycogen. Free fatty acids are these alternate source and generate ketone bodies that accumulate and lead to the development of acidosis. This is the first case of a non-diabetic patient at our institution. We found no other reports at the national level. There are some cases in the world literature associated with fasting from vomiting during the third trimester of pregnancy, psychiatric disorders, strict dieting, gastric band dysfunction and alcohol abuse. Conclusions: The anesthesiologist must be aware of this possibility in patients with fasting-induced metabolic acidosis with normal lactate values and hemodynamic impairment that are either too young or too old, non-diabetic and with no history of alcohol abuse. The anion gap calculation tool is a simple diagnostic approach. The incidence of the condition increases during pregnancy.