Abstract

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymatic disorder of red blood cells in humans. It is estimated that about 400 million people are affected by this deficiency.1 The G6PD enzyme catalyzes the first step in the pentose phosphate pathway, leading to antioxidants that protect cells against oxidative damage.2 A G6PD-deficient patient, therefore, lacks the ability to protect red blood cells against oxidative stresses from certain drugs, metabolic conditions, infections, and ingestion of fava beans.3 The following is a literature review, including disease background, pathophysiology, and clinical implications, to help guide the clinician in management of the G6PD-deficient patient. A literature search was conducted in the following databases: PubMed, The Cochrane Library, Web of Science, OMIM, and Google; this was supplemented by a search for selected authors. Keywords used were glucose-6-phosphate dehydrogenase (G6PD) deficiency, anesthesia, analgesia, anxiolysis, management, favism, hemolytic anemia, benzodiazepines, codeine, codeine derivatives, ketamine, barbiturates, propofol, opioids, fentanyl, and inhalation anesthetics. Based on titles and abstracts, 23 papers and 1 website were identified. The highest prevalence of G6PD is reported in Africa, southern Europe, the Middle East, Southeast Asia, and the central and southern Pacific islands; however, G6PD deficiency has now migrated to become a worldwide disease. Numerous drugs, infections, and metabolic conditions have been shown to cause acute hemolysis of red blood cells in the G6PD-deficient patient, with the rare need for blood transfusion. Benzodiazepines, codeine/codeine derivatives, propofol, fentanyl, and ketamine were not found to cause hemolytic crises in the G6PD-deficient patient. The most effective management strategy is to prevent hemolysis by avoiding oxidative stressors. Thus, management for pain and anxiety should include medications that are safe and have not been shown to cause hemolytic crises, such as benzodiazepines, codeine/codeine derviatives, propofol, fentanyl, and ketamine. The authors of this article make 5 particular recommendations: (1) Anyone suspected of G6PD deficiency should be screened; (2) exposure to oxidative stressors in these individuals should be avoided; (3) these patients should be informed of risks along with signs and symptoms of an acute hemolytic crisis; (4) the clinician should be able to identify both laboratory and clinical signs of hemolysis; and finally, (5) if an acute hemolytic crisis is identified, the patient should be admitted for close observation and care.