[Risk factors for nausea and vomiting after adolescent idiopathic scoliosis surgery]

To explore risk factors for postoperative nausea and vomiting (PONV) that requires intervention with medications during adolescent idiopathic scoliosis (AIS) surgery.

We analyzed the data of 986 patients with AIS (including 156 male and 830 female patients) undergoing scoliosis surgery through a posterior approach between December, 2012 and January, 2016 in Nanjing Drum Tower Hospital. The data were collected from the patients including ASA grade, body mass index (BMI), Cobb angle, preoperative respiratory and cardiovascular diseases, operation time, type of anesthesia, quantity of intraoperative liquid infusion, blood loss, urine volume, the lowest MAP and CVP, intraoperative fentanyl consumption, and intraoperative administration of dexmedetomidine, dexamethasone, ondansetran and droperidol. The incidence of PONV in 48 h following the surgery, hemoglobin variation after operation (ΔHb), postoperative analgesia, times of use and types of antiemetic drugs, and postoperative hospital stay were recorded for all the patients. The potential risk factors of PONV within 48 h were analyzed using univariate analysis and multivariate logistic regression.

Of the 986 patients analyzed, 151 (15.3%) experienced PONV within 48 h following surgeries for AIS. Multivariate logistic regression analysis suggested that an high intraoperative fentanyl dose (> 0.65 mg; OR=9.303, 95% CI: 2.373-8.622, P < 0.001), an obvious ΔHb (> 28.5 g/L; OR=1.107, 95% CI: 1.060-1.157, P < 0.001), and postoperative analgesia with fentanyl (OR=11.671, 95% CI: 2.381-11.284, P < 0.001) were risk factors for PONV. Intraoperative administration of dexmedetomidine (OR=0.027, 95% CI: 0.006-0.123, P=0.002) and dexamethasone combined with ondansetron (OR=0.241, 95%CI: 0.066-0.886, P=0.032) were protective factors against PONV.

A high-dose intraoperative fentanyl consumption, a marked ΔHb, and postoperative analgesia with fentanyl are risk factors for PONV while intraoperative administration of dexmedetomidine and dexamethasone combined with ondansetron are protective factors against PONV following surgeries for AIS.