Clinical study of E-PASS system for peri-operative morbidity of spinal surgery for degenerative scoliosis

Objective To evaluate the feasibility of the Estimation of Physiologic Ability and Surgical Stress (E-PASS) system to predict peri-operative risk in degenerative scoliosis patients scheduled for spinal surgery. Methods Clinical data of 227 cases with degenerative scoliosis (Male∶Female=57∶170, Mean age=66.2±7.7 years), who accepted the operation of instrumentation and fusion in our hospital from January 2013 to July 2017, were retrospectively reviewed according to the E-PASS system, including peri-operative complications. Both hospital stayand post-operative hospital staywere compared between the groups with and withoutthe complications using t test. All E-PASS scores, including Preoperative Risk Score (PRS), Surgical Stress Score (SSS) and Comprehensive Risk Score (CRS), were analyzed between the two groups using Mann-Whitney Utest.The relationship between complications and PRS, SSS and CRS were analyzed using Spearmancorrelation analysis. The predictiveaccuracy of PRS, SSS and CRS were analyzed using the area under the receiver operating characteristic (ROC) curve (AUC). Results There were a total of 47 patients (20.7%) suffering peri-operative complications, including 27 cases (11.9%) with complications at surgical sites and 23 cases (10.1%) with complications at non-surgical sites. Both hospital stay (t=-4.722, P<0.001)and post-operative hospital stay (t= -4.867, P<0.001) were increased because of the complications. All E-PASS scores, including PRS (P=0.005), SSS (P=0.003) and CRS (P<0.001) were significantly higher in patients with peri-operative complications and they were linearly correlated with the overall incidence of the complications(ρ=0.185-0.259). In particular, PRS was correlated with complications at non-surgical sites (ρ=0.162) and SSS with surgical site complications(ρ=0.162). The area under the receiver operating characteristic curve (AUC) for PRS and SSS was higher in patients with complications at non-surgical and surgical sites (AUC=0.655 and 0.650), respectively.The AUC for CRS exhibited good predictive power for both types of complications (AUC=0.662 and 0.631). Conclusion The peri-operative morbidity of spinal surgery for degenerative scoliosis was relatively higher. The E-PASS system could correctly predict the morbidity. Key words: Adult; Lumbar vertebrae; Intervertebral disc degeneration; Scoliosis; Spinal fusion; Intraoperative complications; Postoperative complications