Friday, September 28, 2018 3:00 PM–4:00 PM abstracts: the gravity of obesity: 228. Rapid bodyweight reduction prior to lumbar fusion surgery associated with poorer postoperative outcomes

Abstract

BACKGROUND CONTEXT Risks of spinal fusion surgery include failed back surgery syndrome, nonunion, hardware failure, infection, bleeding, nerve root damage, pulmonary embolus, myocardial infarction, and stroke. It has been documented in several studies that these risks are amplified in the obese patient. Recent evidence suggests that rapid weight loss in the form of bariatric surgery may be associated with decreased bone mineral density and Vitamin D levels. It is unclear, however, whether metabolic changes in bone mineral density, in the setting of rapid weight loss, affect postoperative outcomes in patients undergoing lumbar fusion. PURPOSE The purpose of this study is to determine whether individuals undergoing a greater than 10% weight loss within 6 months prior to lumbar fusion will have lower postoperative complications. STUDY DESIGN/SETTING Retrospective database review. PATIENT SAMPLE A total of 129 patients undergoing lumbar fusion surgery with prior weightloss. OUTCOME MEASURES Post operative LOS, rates of: SSI, wound disruption, pneumonia, unplanned intubation events, acute renal failure, acute MI, transfusions, DVT, sepsis, PE. METHODS All available NSQIP datasets spanning 2005-2015 were included in the study. Patients who underwent lumbar fusion surgery during that time were selected based on CPT code. Patients were then further stratified into two groups based on 10% weight loss within the past 6 months prior to surgery. Patients with a history of malignancy or any chronic disease were excluded. Each patient in the weight loss(WL) group was matched with a randomized nonweight loss patient based on age, sex, smoking status, and BMI. Paired two-tailedT-tests were then used to compare surgical outcomes amongst the WL and non-WL lumbar fusion populations. RESULTS From 2005 to 2014, 4,609,299 surgical events were recorded in the NSQIP dataset. Of these patients, 39,742 patients underwent lumbar fusion surgery, and 129 (3.2%) of these lumbar fusion patients lost greater than 10% of their body weight in the 6 months prior to their surgery following exclusion of patients with malignancy or chronic disease. When compared the non-WL group, those in the WL group had a significantly longer total length of hospital stay (9.7 vs. 4.0 days; p CONCLUSIONS On a nationwide scale, organic weight loss of greater than 10% of body weight within 6 months prior to lumbar spine fusion surgery is associated with worse post operative outcomes and longer length of stay.