Defining Rates and Causes of Mortality Associated With Spine Surgery

Abstract

STUDY DESIGN: Retrospective review of prospectively collected databases. OBJECTIVE: To compare 2 approaches for assessment of mortality associated with spine surgery. SUMMARY OF BACKGROUND DATA: The Scoliosis Research Society collects morbidity and mortality data from its members. Previously, this included details for all spine cases and all complications. To reduce time burden and improve compliance, collection was changed to focus on a few major complications (death, neurological deficit, and blindness) for specific deformity diagnoses (scoliosis, spondylolisthesis, and kyphosis) and only for cases with complications. METHODS: Data were extracted from the Scoliosis Research Society from 2004-2007 (detailed system) and 2009-2011 (simplified system). As an anchor for comparison, mortality rates were compared between the systems. RESULTS: Between 2009 and 2011, the number of deformity cases reported were 87,162, with 131 deaths (1.50/1000 cases). The mean age of these 131 patients was 50, mean American Society of Anesthesiologists grade was 2.8, 10% were smokers, and 18% had diabetes. Rates of death (per 1000 cases) were: idiopathic scoliosis (0.4), congenital scoliosis (1.3), neuromuscular scoliosis (3.6), other scoliosis (3.1), spondylolisthesis (0.6), and kyphosis (4.7). Common causes of mortality included respiratory (48), cardiac (32), sepsis (12), organ failure (9), and blood loss (7). Compared with the detailed system, the simplified system had greater surgeon compliance (79% vs. 62%, P < 0.001), greater number of deformity cases per reporting surgeon per year (139 vs. 90, P < 0.001), and modest but significantly lower mortality rates (1.50 vs. 1.80/1000 cases; P < 0.001). Causes of death were comparable between the 2 systems. CONCLUSION: On the basis of the simplified collection system, the rate of mortality for spinal deformity surgery was 1.50 per 1000 cases. Compared with the detailed system, the simplified system had significantly improved compliance and similar mortality rates. Although the simplified system is limited by less data collected, it achieves better compliance and may prove effective, especially if supplemented with focused data collection modules.