Cardiopulmonary bypass (CPB) produces hemodynamic and inflammatorydisorders involving changes in vascular permeability and regional bloodflow and alterations of coagulation and complement systems. It has beenreported that an abnormal release of vasoactive substances during CPB, likebradykinin or nitric oxide, could play a role. The aim of this study was toinvestigate the changes in nitric oxide (NO) release occurring in patientsundergoing CPB, under both hypothermic and normothermic conditions. Fortypatients (mean age 61.4 +/- 8.4 years) undergoing coronary bypass surgerywere studied. In 20 patients (group A) systemic hypothermic CPB andantegrade cold intermittent crystalloid cardioplegia were used. Theremaining 20 cases (group B) underwent surgery under systemic normothermicCPB and with antegrade warm blood intermittent cardioplegia. Nitric oxidewas measured as the nitrite plasma level (NPL) by the Gries reaction. Thetime course of changes in NPL were obtained by collecting five whole bloodsamples: before CPB, 10 and 30 min after the start of CPB, and 10 and 60min after the end of CPB. Although there were no significant variations ofNPL shortly after the start of CPB (10 min after), values measured 30 minafter CPB commencement and 10 min after the end of CPB showed a significantincrease (P <0.0001) in both groups. Considering the two groupsseparately, NPL changes seemed to be similar, so independent oftemperature; however, in group B higher values of NPL were measured during(30 min) and after (60 min) CPB (P <0.0001). In conclusion, during CPBthere is a progressive increase, independent of temperature in NOrelease.
- Cardiopulmonary bypass
- Heart surgery
- Nitric oxide
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Pulmonary and Respiratory Medicine