Drain Utilization Does not Improve Outcomes after Incidental Durotomies in Elective Spine Surgery

Introduction: Incidental durotomy (ID) is among the most common complications of spine surgery. While dural repair is considered important in managing ID postoperatively, significant discordance exists as to optimal drain management in these patients in evaluating persistent fluid leakage. Our study aims to examine the impact of postoperative drain output on short-term postoperative outcomes for patients who experienced incidental durotomies following elective lumbar spine surgery.

Methods: A retrospective cohort study was conducted of all adult patients who experienced an ID after primary lumbar decompression and/or fusion from 2017-2021. Patient demographics, surgical characteristics, surgical outcomes, and drain data were collected via chart review. Patients were grouped based on readmission status, and final 8-hour drain output. Those with a final 8-hour drain output ≥40 mL were classified in the high drain output (HDO) group, while those with < 40 mL were included in the lower drain output (LDO) group, consistent with prior literature. Bivariable and multivariable analyses were conducted.

Results: A total 179 patients were included, of which 66 had HDO and 113 had LDO during their final 8 hours before drain discontinuation. The were no significant differences between drain output groups in patient and surgical characteristics or in postoperative outcomes such as length of stay (HDO [4.02 days] vs LDO [4.26 days], p=0.269), hospital readmissions (HDO [10.6%] versus LDO [7.96%], p=0.744), or requiring reoperation during readmission (HDO [6.06%] versus LDO [2.65%], p=0.5944). Sixteen patients were readmitted from the study cohort, and there were no differences in overall drain output, drain duration, or average drain output per day (all, p>0.05).

Conclusion : In patients undergoing primary lumbar decompression and/or fusion with an incidental durotomy, drain parameters do not significantly influence postoperative outcomes. Adequate fascial closure and dural repair may be satisfactory for standard patient discharge without need of drain placement or management of drain output.