Inpatient Outcomes in Dialysis-dependent Patients Undergoing Elective Lumbar Surgery for Degenerative Lumbar Disease.

Study Design. Retrospective cohort study. Objective. To evaluate hospital outcomes in dialysis-dependent patients undergoing elective lumbar surgeries. Summary of Background Data. Because of their overall poor health status and concomitant comorbidity burden, spinal surgery in dialysis-dependent patients represents a significant challenge to spine surgeons. Large studies evaluating their immediate postoperative outcomes in elective lumbar surgery are lacking. Methods. Utilizing the National Inpatient Sample, an estimated 1834 dialysis-dependent patients undergoing elective lumbar spine surgery for degenerative lumbar conditions were compared to an estimated 2,522,594 non-dialysis-dependent patients undergoing the same procedures between 2002 and 2012. Our primary outcomes measures included postoperative complication rates, hospital length of stay, and total hospital costs. Results. Mean age of dialysis-dependent patients was 64.2 years compared to 59.9 in the non-dialysis-dependent cohort (P < 0.001). Dialysis-dependent patients had substantially higher inpatient mortality rates (1.8% vs 0.1%; P < 0.001), major complication rates (8.1% vs 1.1%; P < 0.001), and an increased need for blood transfusion (18.3% vs 12.5%; P < 0.001). Multivariate analysis revealed that dialysis dependence independently increased odds of in-hospital mortality (odds ratio = 8.30; 95% confidence interval 5.78-11.93; P < 0.001) and odds of a major postoperative complication (odds ratio = 3.63; 95% confidence interval 3.49-3.89; P < 0.001). Dialysis dependence was associated with an increased mean length of stay of 3.3 days (P < 0.001) and a significant increase in hospital costs when stratified by procedure type. Conclusion. Dialysis dependence is associated with poorer immediate postoperative outcomes and increased hospital costs when compared to non-dialysis-dependent patients. In addition, an increased need for postoperative transfusion should be anticipated in this patient population. Further studies are warranted to confirm these findings.