Percutaneous Endoscopic Interlaminar Lumbar Discectomy with Local Anesthesia for L5-S1 Disc Herniation: A Feasibility Study.

Background: General anesthesia (GA), which is routinely applied in patients who undergo percutaneous endoscopic interlaminar lumbar discectomy (PEILD) of L5-S1 disc herniation, is closely associated with postoperative cognitive dysfunction (POCD) in the elderly. Local anesthesia (LA) is an alternative pain control protocol that has not yet been fully evaluated.

Objectives: To evaluate the feasibility of LA in PEILD compared with GA.

Study Design: A retrospective study.

Setting: This study took place at the First Affiliated Hospital of Harbin Medical University.

Methods: A total of 120 patients (aged 60-85 years) diagnosed with L5-S1 disc herniation and with American Society of Anesthesiologists fitness grade I or II between March 2016 and August 2017 were enrolled in the current study. Patients were randomly divided into LA group and GA group. For LA, 0.25% lidocaine was injected layer-by-layer into skin, subcutaneous tissue, fasciae, lumbar facet joint, muscle, and ligamentum flavum followed by injection of 1.33% lidocaine into epidural space; for GA, propofol, sufentanil, and cisatracurium were infused intravenously at 1 to 2 mg/kg, 0.3 µg/kg, and 0.15 mg/kg, respectively. Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and MacNab Criteria (MNC) evaluated the feasibility of LA as pain control protocol in comparison to GA before and after operation. The development of POCD was assessed by the Mini-Mental State Examination 1 and 7 days postsurgery. Feasibility of LA as a pain control protocol was also evaluated by patient's willingness to receive the same surgical procedure immediately and 24 hours after the surgery, and intraoperative fluoroscopy use, blood loss, surgery duration, postoperative bed confinement, and duration and cost of hospital stay were also evaluated.

Results: Patients in both LA and GA groups had comparable VAS grade, ODI, and MNC pre- and post-PEILD, with significant pain reduction after operation. However, POCD developed only in GA group but not in LA group. In addition, compared with GA, LA group did not require postoperative bed confinement, had significantly shorter hospital stay, and lower hospital cost. Low intraoperative VAS grade and willingness to receive the same procedure reflected the acceptance of LA by patients.

Limitations: The development of POCD was examined only 7 days after operation. The follow-up should be extended to 3 months and 2 years postoperation.

Conclusions: LA has satisfactory pain control and low-risk of POCD in PEILD and is well accepted by patients. The benefits of LA are no postoperative bed confinement, faster recovery, shorter hospital stay, and lower hospital cost.

Key Words: L5-S1 disc herniation, older patients, percutaneous endoscopic interlaminar lumbar discectomy, local anesthesia, general anesthesia, postoperative cognitive dysfunction, American Society of Anesthesiologists grade, Oswestry Disability Index, MacNab Criteria, Mini-Mental State Examination.