[Significance of tissue pH in the prognosis of postoperative complications in heart surgery patients].
Ischemia of the gastrointestinal mucosa is characterized by acidosis in the submucosal layer during the majority of interventions, which necessitates monitoring of tissue pH (pHi) of the abdominal organs during aortocoronary bypass surgery and the immediate postoperative period. The pHi was measured by gastrotonometry with a nasogastral tube (Trip catheter) and Tonocap-TC200 device (Datex Engstrom, Finland); pHi was measured in 17 patients in department of intensive care on days 1 or 2 after cardiosurgical interventions with at least 120-min artificial circulation and in 23 patients during the operation. Surgical treatment consisted in correction of acquired valvular diseases, myocardial revascularization (shunting operations), and combinations of these operations. The first stage of investigation revealed a relationship between decreased pHi level to the acid values and complicated course of the postoperative period. The second stage showed that postoperative complications occurred in 27.2% cases only in patients subjected to long artificial circulation bypass (more than 120 min). The frequency of complications were 2-fold more in the patients with tissue acidosis (pHi < 7.35) during surgery than in patients with normal and alkaline pHi values. The following complications occurred: acute pancreatitis, acute peptic ulcer, acute renal and polyorgan failure. Comparative analysis of pHi and other metabolic markers of arterial blood showed a correlation between these parameters, but pHi was more specific for the diagnosis of tissue ischemia. Hence, a low invasive highly specific method of gaseous gastrotonometry helps evaluate the blood supply to abdominal organs during and after cardiac surgery with artificial circulation and predict postoperative gastrointestinal and grave systemic complications (sepsis, acute renal failure, and polyorgan failure).