Effect of increased systemic oxygen delivery on postoperative outcomes and quality of life in elderly undergoing major abdominal surgery: A randomised controlled trial

Studies comparing the intentional increase in oxygen delivery and normal oxygen delivery during general anaesthesia in elderly patients undergoing major abdominal surgery are limited and have reported contradictory findings. Therefore, the study aimed to evaluate the effect of intraoperative increase in systemic oxygen delivery on postoperative outcomes and quality of life in elderly patients undergoing major abdominal surgery. This randomised, blinded, parallel-arm, pragmatic clinical trial included elderly patients of >60 years of age undergoing major abdominal surgery. The patients in the intervention arm received noradrenaline or increased fractional inspiration of oxygen to augment central venous oxygen saturation ⩾75%. The primary outcome measure was composite of in-hospital mortality and major organ complications. The secondary outcome measure included comparison of quality of life. A total of 160 patients were assessed for eligibility, and 146 were randomised in the study groups. The mean arterial and central venous oxygen saturation increased and were significantly higher in the intervention arm. The composite primary outcome occurred in 49.31% in the intervention arm and 57.53% in the usual care arm (relative risk; 95% confidence interval: 0.85; 0.63-1.16; absolute risk reduction; 8.22%; p = 0.32). Furthermore, quality of life at the end of three months was similar (0.658 ± 0.19 versus 0.647 ± 0.19; p = 0.771). In conclusion, central venous oxygen saturation–guided increase in systemic oxygen delivery during the intraoperative period of major abdominal surgery in elderly patients did not reduce predefined composite outcome of in-hospital mortality or organ-specific complications.