Does the drain placement technique affect the amount of postoperative spinal epidural hematoma after microendoscopic decompressive laminotomy for lumbar spinal stenosis?

Abstract

Objective: To prospectively evaluate with magnetic resonance imaging (MRI), the relationship between the distance from the incision of the drain output location and postoperative spinal epidural hematoma (SEH) in patients performed with microendoscopic decompressive laminotomy (MEDL) for lumbar spinal stenosis. Methods: Between January 2016 and June 2018, three different kinds of drain placement techniques, according to the drain output location, were performed to a total of 184 patients after MEDL for single-level spinal stenosis. The location of the drain output was within the incision in group 1, 1 cm lateral of the incision in group 2, and 5 cm lateral of the incision in group 3. At 24 h postoperatively, before removal of the drain, MRI examination was carried out in patients. A specific classification was developed by the authors to measure SEH, and the groups were evaluated by comparison. Results: The mean postoperative dural sac cross-sectional area was 1.73 cm2 (standard deviation (SD): 0.711) in group 1, 1.66 cm2 (SD: 0.732) in group 2, and 1.52 cm2 in group 3 (SD: 0.841).The mean cross-sectional area of the postoperative hematoma was 1.45 cm2 (SD: 1.007) in group 1, 1.57 cm2 (SD: 1.053) in group 2, and 2.11 cm2 (SD: 1.024) in group 3. Four grades were defined according to the specific classification. According to this classification, grades C and D postoperative hematomas were determined at a statistically significantly higher rate in group 3 patients (drain output 5 cm lateral from the incision) compared to the other groups ( p = 0.000). No significant difference was determined between groups 1 and 2 in respect of hematoma classification. Conclusion: In conclusion, it was determined that better drainage was provided in groups 1 and 2, where the drain output location was in the incision or close to it.

Incidence of postoperative symptomatic spinal epidural hematoma requiring surgical evacuation: a systematic review and meta-analysis

“…On the other hand, poor visualization due to smaller surgical fields increases the difficulty of observing the bleeding site adequately than in open surgery. So the bleeding during the minimally invasive procedure may be masked [32,54]. In addition, bone bleeding is difficult to control intraoperatively because the usage of bone wax is affected by the saline flow.…”

Symptomatic Postoperative Epidural Hematoma in the Lumbar Spine

“…In a separate prospective study of 184 patients treated with single-level endoscopic decompression for lumbar spinal stenosis, placement of drain tubes within the surgical incision itself or 1 cm lateral to it was found to significantly reduce the volume of postoperative hematoma when compared with drain tubes which exited the skin 5 cm lateral from the incision. 51 The authors' practice reflects the reasoning that the theoretical benefit, compared with the very low-risk profile, of evacuating postoperative hematoma with subfascial drains postoperatively warrants their utilization despite an acknowledged lack of known reduction in rates of SPEH.…”

Microendoscopic Lumbar Posterior Decompression Surgery for Lumbar Spinal Stenosis: Literature Review

“…Patients with epidural hematoma at 1 week exhibited less expansion of the dural sac after 1 year, and the RDQ and Prolo scale scores were significantly worse than those in patients without hematoma at 1 week. Merter and Shibayama [ 46 ] also conducted an MRI study to investigate the appropriate location of the drain output in microendoscopic surgery. They divided the patients into three groups according to the location of the drain output: (1) within the incision, (2) 1 cm lateral to the incision, and (3) 5 cm lateral to the incision.…”