Incidence and risk factors for gastrointestinal hemorrhage after lumbar fusion.

STUDY DESIGN: Retrospective database analysis.

OBJECTIVE: To determine rates of gastrointestinal (GI) hemorrhage after lumbar fusions, a population-based database was analyzed to identify incidence, mortality, and risk factors associated with anterior (ALF), posterior (PLF), and simultaneous anterior/posterior (APLF) lumbar fusions.

SUMMARY OF BACKGROUND DATA: GI hemorrhage after lumbar surgery is a rare complication that can have devastating consequences. Incidences of GI bleeding after lumbar fusion are not well characterized in the current literature.

METHODS: Data from the Nationwide Inpatient Sample were obtained from 2002 to 2009. Patients undergoing ALF, PLF, and APLF for degenerative pathologies were identified and the incidence of GI hemorrhage was evaluated. Patient demographics, Charlson Comorbidity Index, length of stay, costs, and mortality were assessed. SPSS version 20 (IBM; Armonk, NY) was used to detect statistical differences between groups and perform logistic regression analyses to identify independent predictors of GI bleeding. A P value of <0.001 denoted significance.

RESULTS: A total of 220,522 lumbar fusions were identified in the United States from 2002 to 2009. Of these, 19,762 were ALFs, 182,801 were PLFs, and 17,959 were APLFs. GI bleeding was noted in ALFs, with 1.1 events per 1000 cases, PLFs with 1.4 events, and APLFs with 1.7 events. Patients with GI bleeding demonstrated greater Charlson Comorbidity Index scores, length of stay, costs, and mortality (P < 0.001). Logistic regression analysis demonstrated independent predictors of GI hemorrhage including advanced age (>65 yr), male sex, blood loss anemia, fluid/electrolyte disorders, metastatic neoplasm, and weight loss (P < 0.001).

CONCLUSION: The results of our study demonstrate very low complication rates of GI hemorrhage across ALFs, PLFs, and APLF cohorts. Across all surgical procedures, the presence of GI bleeding complications was associated with greater comorbidity, length of stay, cost, and mortality. We strongly advise physicians to perform stringent perioperative assessments of risk factors and to provide prompt medical attention to minimize the impact of GI bleeding complications.

LEVEL OF EVIDENCE: 3.