Catabolic Processes in Cardiosurgical Patients

Abstract

Objective: to evaluate catabolic and anabolic processes in cardiosurgical patients during heart operations under extracorporeal circulation.

Subjects and methods. Seventy-one patients with coronary heart disease (CHD) and acquired cardiac defects (ACD), who had been operated on under extracorporeal circulation, were examined. The plasma levels of cortisol, adrenaline, insulin, growth hormone, and albumin were measured. For determination of daily nitrogen excretion, blood and diurnal urine were sampled at the following stages: 1) before surgery; 2) postoperative (PO) day 1; 3) PO day 3; 4) PO day 7; 5) PO day 14; 6) PO day 21.

Results. The preoperative daily nitrogen excretion in CHD patients was 10.4±1.0 g/day. By PO day 3, there was a significant increase in nitrogen excretion by 66%, up to 17.3±1.6 g/day (p<0.01). In ACD patients, the baseline daily urinary nitrogen excretion was 11.9±1.7 g/day. By PO day 3, there was a 1.4-fold increase in this index — up to 16.3±2.0 g/day. Daily nitrogen excretion significantly increased up to 17.1±1.2 g/day by the end of the first PO week (p<0.05), by exceeding the baseline values by 44%. Nitrogen excretion peaked by the end of PO days 14 (17.2±1.6 g/day (p<0.05). By hospital discharge, nitrogen excretion was 23% greater than its baseline preoperative level (p>0.05). In cardiosurgical patients, an increase in daily nitrogen excretion occurred with the elevated concentrations of the stress hormones cortisol and adrenaline.

Conclusion. The magnitude of catabolic reactions after cardiosurgical interventions depends on the type of cardiac disease. In patients with CHD, the maximum catabolic reactions were recorded on PO day 3 whereas in those with ACD, they continued within three weeks postoperatively.