POSTOPERATIVE HYPERAMYLASEMIA IN CARDIAC-SURGERY

The mechanism of postoperative hyperamylasaemia was studied in 48 pati ents undergoing coronary artery bypass grafting (CABG). Mild hyperamyl asaemia developed in 87% of the patients, and in 10% the serum amylase activity was >1 000 U/l. Serial measurements of serum salivary (S-) a nd pancreatic (P-) isoamylases indicated that hyperamylasaemia was hig hest 24 hours after CABG and consisted mainly of P-amylase component. Serum creatinine, creatinine clearance and urinary albumin concentrati on remained normal after CABG, excluding severe renal damage. The frac tional clearance (i.e. relative to creatinine clearance) of P-amylase decreased more than that of S-amylase (from 3.6 to 0.9% vs 1.3 to 0.8% ). Decreased rate of excretion into urine, rather than pancreatic cell ular damage, is the main source of hyperamylasaemia after CABG.