Gastrointestinal tract protection with nitric oxide in aortic arch surgery: a randomized study

Objective. To assess the efficacy of perioperative nitric oxide delivery for gastrointestinal tract protection in patients undergoing aortic arch surgery under cardiopulmonary bypass (CPB) and circulatory arrest (CA). Material and methods. The study included 62 patients who underwent aortic arch surgery under CPB and CA. In the NO group, nitric oxide (NO) was delivered at a concentration of 80 ppm into ventilator and CPB circuit throughout surgery, as well as into ventilator circuit for 6 hours after surgery. The control group received standard protocol of surgery, anesthesia, CPB and CA. The primary endpoint was i-FABP concentration, secondary endpoints — serum aspartate aminotransferase, alanine aminotransferase, albumin, total bilirubin and creatinine, bowel function restoration time, incidence of postoperative complications, ICU- and hospital-stay. Results. In the NO group, i-FABP concentration in 20 min after CPB was statistically lower compared to the control group (p=0.021). Serum creatinine and total bilirubin after 1 postoperative day were lower (p=0.007 and p=0.034, respectively). Serum albumin after 1 postoperative day was higher in this group (p=0.026). There was earlier bowel function restoration in the NO group (p=0.007). Pneumonia was more common in the control group (p=0.005). Length of ICU-stay was shorter in the NO group (p=0.007). Conclusion. NO delivery into ventilator and CPB circuit during aortic arch surgery has a protective effect on splanchnic organs. This maneuver is associated with less incidence of postoperative pneumonia and shorter ICU-stay.