Influence of blood loss on cerebral oxygen saturation in paediatric patients undergoing surgery for scoliosis correction: A retrospective observational study.

ABSTRACT

AIM: Surgery for congenital scoliosis correction in children is often associated with considerable blood loss. Decrease in regional oxygen saturation (rScO2) can reflect insufficient cerebral perfusion and predict neurological complications. This retrospective observational study explored the relationship between blood loss during this surgery and a decrease in rScO2 in children. METHODS: The following clinical data of children aged 3-14 years who underwent elective posterior scoliosis correction between March 2019 and July 2021 were collected age, sex, height, weight, baseline rScO2, basal mean invasive arterial pressure (MAP), preoperative Cobb angle, number of surgical segments, preoperative and postoperative haemoglobin level, percentage of lowest rScO2 below the baseline value that lasted 3 min or more during the operation (decline of rScO2 from baseline, D-rScO2%), intraoperative average invasive MAP, end-tidal carbon dioxide pressure, fluid infusion rate of crystalloids and colloids, operation time, and percentage of total blood loss/patient's blood volume (TBL/PBV). RESULTS: A total of 105 children were included in the study. Massive haemorrhage (TBL/PBV ≥50%) was reported in 53.3% of patients, who had significantly higher D-rScO2 (%) (t = -5.264, P < 0.001) than those who had non-massive haemorrhage (TBL/PBV <50%). Multiple regression analysis revealed that TBL/PBV (ß = 0.04, 95% CI 0.018-0.062, P < 0.05) was significantly associated with D-rScO2%. CONCLUSIONS: Intraoperative massive blood loss in children significantly increased D-rScO2%. Monitoring should be improved, and timely blood supplementation should be performed to ensure maintenance of the blood and oxygen supply to vital organs, improve the safety of anaesthesia, and avoid neurological complications.