Effect of Haemodynamic Changes on Epithelium-related Intestinal Injury in Off-pump Coronary Surgery

Abstract

Intestinal injury is thought to play a central role in the occurrence of multiorgan dysfunction after on-pump coronary surgery. Clinical benefits of off-pump revascularisation remain, however, controversial. Hepatic enzymes and plasmatic IL-6, IL-8 and intestinal-type fatty acid binding protein (I-FABP) were determined in 20 patients (age 65-75) undergoing either on-pump (n = 10) or off-pump (n = 10) coronary surgery. Haemodynamic and biochemical parameters, catecholamine and volume therapy were monitored. Central venous pressure (CVP) was significantly higher in the off-pump group during and 12h after operation (9.5 ± 1.35 vs. 6.21 ± 0.63 mmH2O, p = 0.012). Higher GGT and GLDH levels occurred in the off-pump group and correlated with the elevated I-FABP levels at 24h (935.8 ± 83.7 vs. 370.4 ± 67.7 pg/mL, p<0.001). CVP correlated with I-FABP peak values (Pearson's coefficient 0.852). IL-6 and IL-8 were released to a lower extent in the off-pump group compared to on pump (p<0.05) at 24h (139.3 ± 27.7 vs. 279.4 ± 56.2 and 15.3 ± 7.4 vs. 38.5 ± 13.8 pg/mL) and at 72 h post-operatively (4.5 ± 2.1 vs. 30.1 ± 12.1 and 7.8 ± 1.2 vs. 17.1 ± 5.2 pg/mL). While inflammatory activation is reduced with CPB avoidance, elevated CVP during off-pump surgery is followed by temporary postoperative enterocyte damage that may threaten the normal function of the gastrointestinal system and lead - in certain groups of high risk patients--to irrecoverable injury.