Risk factors of perioperative complications for posterior spinal fusion in degenerative scoliosis patients: a retrospective study

BACKGROUNDS: Rare study has been conducted to detect risk factors of perioperative complications, which are closely related to preoperative status of the patients and surgical stress. The aim of this study is to detect these relationships in degenerative scoliosis (DS) patients. METHODS: Perioperative complications of 226 cases with DS (56 males and 170 females; 65.5 ± 8.1 years old), who accepted posterior fusion in our hospital from January, 2013 to July, 2017, were retrospectively reviewed. Potential risk factors were first compared between patients with or without perioperative complications using student t test or Chi-squared test. Then, the unevenly distributed variables between the two groups were analyzed with binary logistic regression model. RESULTS: All patients separately underwent decompression with short limited instrumentation (116, 51.3%) or with long instrumentation for correction (110, 48.7%). The mean operation duration (OD) was 216.9 ± 64.2 min and the average amount of bleeding was 587.4 ± 357.2 ml. 44 cases (19.5%)suffered from the complications during the perioperative phase, including incision complications (5.3%), urinary infection (3.5%), dura tears/cerebrospinal fluid (CSF) leakages (3.5%) and new neurological deficits (2.7%). Hospital stay was significantly extended for the complications (p < 0.001). Univariate analysis showed that OD (p < 0.001), bleeding (p = 0.014), American Standards Association (ASA) grade > 2 (p = 0.011) and RBC transfusion≥4 U(p = 0.028) were associated with these complications. Multivariate logistic regressions revealed that only ASA grade > 2(p = 0.011, Odds Ratio[OR] = 4.104, 95% Confidence Interval[CI] = 1.413~ 11.917) and OD (p = 0.013, OR = 2.697, 95% CI = 1.233~ 5.899) were the independent risk factors. CONCLUSIONS: The high morbidity of perioperative complications for posterior spinal fusion would significantly extend hospital stay of DS patients. It was independently related to higher ASA grade and longer OD.