Awake spinal surgery: simplifying the learning curve with a patient selection algorithm

Abstract

OBJECTIVE There is a learning curve for surgeons performing “awake” spinal surgery. No comprehensive guidelines have been proposed for the selection of ideal candidates for awake spinal fusion or decompression. The authors sought to formulate an algorithm to aid in patient selection for surgeons who are in the startup phase of awake spinal surgery. METHODS The authors developed an algorithm for selecting patients appropriate for awake spinal fusion or decompression using spinal anesthesia supplemented with mild sedation and local analgesia. The anesthetic protocol that was used has previously been reported in the literature. This algorithm was formulated based on a multidisciplinary team meeting and used in the first 15 patients who underwent awake lumbar surgery at a single institution. RESULTS A total of 15 patients who underwent decompression or lumbar fusion using the awake protocol were reviewed. The mean patient age was 61 ± 12 years, with a median BMI of 25.3 (IQR 2.7) and a mean Charlson Comorbidity Index of 2.1 ± 1.7; 7 patients (47%) were female. Key patient inclusion criteria were no history of anxiety, 1 to 2 levels of lumbar pathology, moderate stenosis and/or grade I spondylolisthesis, and no prior lumbar surgery at the level where the needle is introduced for anesthesia. Key exclusion criteria included severe and critical central canal stenosis or patients who did not meet the inclusion criteria. Using the novel algorithm, 14 patients (93%) successfully underwent awake spinal surgery without conversion to general anesthesia. One patient (7%) was converted to general anesthesia due to insufficient analgesia from spinal anesthesia. Overall, 93% (n = 14) of the patients were assessed as American Society of Anesthesiologists class II, with 1 patient (7%) as class III. The mean operative time was 115 minutes (± 60 minutes) with a mean estimated blood loss of 46 ± 39 mL. The median hospital length of stay was 1.3 days (IQR 0.1 days). No patients developed postoperative complications and only 1 patient (7%) required reoperation. The mean Oswestry Disability Index score decreased following operative intervention by 5.1 ± 10.8. CONCLUSIONS The authors propose an easy-to-use patient selection algorithm with the aim of assisting surgeons with patient selection for awake spinal surgery while considering BMI, patient anxiety, levels of surgery, and the extent of stenosis. The algorithm is specifically intended to assist surgeons who are in the learning curve of their first awake spinal surgery cases.

The “In-Parallel” Technique for Awake, Bilateral Simultaneous Minimally Invasive Transforaminal Lumbar Interbody Fusion and Multilevel Lumbar Decompression

“…In the algorithm, the authors suggest factors portending suitability for general anesthesia or awake spinal fusion, stratified by whether a patient is receiving a decompression or a fusion—but not both. 23 As reported here, we believe there are a number of patients who necessitate both—and both approaches may be undertaken simultaneously. This expands the number of patients with multilevel lumbar pathology who may be eligible for awake surgery.…”

“…This expands the number of patients with multilevel lumbar pathology who may be eligible for awake surgery. Although awake spinal fusion is gaining in popularity, 22-24,26-28 the relative nascency of its performance suggests that improvements and modifications—such as that described here—can be made. For instance, we use a 2-dimensional (2-D) navigation instrument tracking platform for pedicle screw placement and dilator advancement.…”

“…Subsequent work by Letchuman reported on the application of the awake spinal protocol by Chan and Mummaneni in 15 patients. 23…”

“…Several studies report the use of spinal anesthetics and long-acting liposomal bupivacaine to conduct minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). 22,23 The duration of spinal anesthesia is dependent on dose and initial sensory level achieved; a 12.5- to 15-mg dose of bupivacaine will result in 2 to 3 hours of anesthesia at the T10 dermatomal level. 29 Given this limited duration, awake lumbar fusions may be most appropriate for one- or two-level fusions.…”

How to start an awake spine program: Protocol and illustrative cases

“…Although fewer studies have described the steps undertaken to perform awake spine surgery ( De Biase et al, 2021 ) and patient selection algorithm ( Letchuman et al, 2021 ), very little has been published with practical instruction on starting an awake spine surgery program. Thus, here we provide a comprehensive template for healthcare providers and leaders for starting an awake spine surgery program.…”