Complications following lengthening of spinal growing implants: is postoperative admission necessary?

OBJECTIVE The aim of this study was to evaluate the effect of postoperative admission status on 30-day perioperative complications in patients with growing spinal instrumentation undergoing surgical lengthening. METHODS This retrospective case-control study of records from the 2014-2015 National Surgical Quality Improvement Program-Pediatric database was performed to identify surgical lengthening procedures of spinal implants in patients with growing instrumentation by Current Procedural Terminology code. The 30-day postoperative complications were classified according to the Clavien-Dindo system. Patients were subdivided according to their postsurgical admission status. Admission status, American Society of Anesthesiologists (ASA) Physical Status classification, tracheostomy, neuromuscular diagnosis, ventilator dependence, and nutritional support were considered as possible risk factors in univariate and multivariate logistic regression analyses. RESULTS A total of 796 patients were identified (mean age 9.09 +/- 3.44 years; 54% of patients were female), of whom 73% underwent lengthening on an inpatient basis. Patients with a tracheostomy or ventilator dependence were more likely to be admitted postoperatively. The overall rate of major complications was 3.5% and did not differ based on admission status (2.8% inpatient vs 3.8% outpatient, p = 0.517). On univariate analysis, ventilator dependence (9.5% vs 2.7%, p = 0.002), need for nutritional support (7.1% vs 2.5%, p = 0.006), and ASA class > II (4.8% vs 1.3%, p = 0.04) placed patients at a higher risk for any postoperative complications. Multivariate analysis identified only ventilator dependence as an independent risk factor for any perioperative complication. CONCLUSIONS Postoperative admission status did not affect the rate of 30-day perioperative complications, readmission, or rate of unplanned operations following lengthening of growing spinal instrumentation. Outpatient lengthening appears to be safe; however, consideration for postoperative admission should be given for those who are ventilator dependent.