Subfascial Drain After Incidental Durotomy and Postoperative Courses: A Retrospective Observational Study

Incidental durotomy (ID) is a common iatrogenic complication in lumbar spine surgery with a reported incidence of 1.7%–14%. ID can lead to a range of clinical sequela including chronic headache, wound complications, or new neurological deficits. This often leads to readmission and reoperation. Use of a subfascial drain is commonly employed in spine surgery to reduce risk of post-operative hematoma or seroma. In the setting of ID, it remains unclear if subfascial drain can prevent post-operative complications or influence the immobilization period. Using the International Classification of Disease (ICD)-10 billing codes, adult patients with degenerative lumbar spine procedures and ID between January 2012 and December 2022 in Alberta, Canada were identified. Exclusion criteria were as follows: 1) no information available on intra-operative ID and management, 2) use of an intrathecal lumbar drain, (in contrast to subfascial drain) 3) associated trauma, tumour, or infection, 4) prolonged admission due to pre-operative neurological deficits or medical comorbidities. The following data was collected: age, sex, comorbidities, surgical indications, primary vs. revision surgery, dural tear repair method, immobilization period, length of hospital stay, timeline of readmission or reoperation due to post-operative complications relating to ID, and post-operative complications. 111 patients met inclusion and exclusion criteria (n=77 for no drain group, n=34 for subfascial drain group). There was no significant difference in repair methods, immobilization periods, surgical indications, or Charlson Comorbidity Index scores between both groups (2.6±2.0 vs. 3.1±2.2; P=0.182). Patients treated with subfascial drain had lower readmission and reoperation rates (41.6% vs. 23.5%; 58.4% vs. 29.4%), and a shorter average length of hospital stay (10.8±21.2 days vs. 8.7±6.6 days; P=0.321). Amongst the 39 patients who required one or multiple reoperations (n=30 for no drain group, n=9 for subfascial drain group), greater rates of surgical site infection (24% vs. 9%), pseudomeningocele (13% vs. 9%), and tonsillar herniation (2% vs. 0%) were noted in the no drain group. Our preliminary data suggest subfascial drain may be associated with less adverse outcomes when managing ID in adult degenerative lumbar spine procedures.