Serum enzymes and isoenzymes after surgery.

Serum creatine kinase, aspartate transaminase, and hydroxybutyrate dehydrogenase activities were abnormal in 76, 50, and 28% respectively of 50 patients studied within 26 hours of surgery. No patient showed clinical evidence of myocardial infarction. Creatine kinase MB isoenzyme elevation, and lactate dehydrogenase LD1 activity greater than LD2 (LD) greater than LD2) were infrequent (6 and 10% respectively). No patient showed the combination of transient MB isoenzyme elevation and LD1 greater than LD2, although their rare association without infarction after surgery is to be anticipated.