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Hidenori Sugano, Yasushi Iimura, Hiroharu Suzuki, Samantha Tamrakar, Takumi Mitsuhashi, Takuma Higo, Tetsuya Ueda, Kazuki Nishioka, Kostadin Karagiozov, and Madoka Nakajima

OBJECTIVE

Tailored surgery to extensively resect epileptogenic lesions using intraoperative electrocorticography (ioECoG) may improve seizure outcomes. However, resection of large areas is associated with decreased memory function postoperatively. The authors assessed whether ioECoG could provide useful information on how to minimize the focus resection and obtain better seizure outcomes without memory deterioration. They examined the postoperative seizure-free period and memory alteration in a retrospective cohort of patients with mesial temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS) in whom the extent of removal was determined using ioECoG findings.

METHODS

The authors enrolled 82 patients with TLE associated with HS who were treated surgically. Transsylvian amygdalohippocampectomy was indicated as the first step. When visual inspection identified interictal epileptic discharges from the lateral temporal lobe on ioECoG, anterior temporal lobectomy (ATL) was eventually performed. The patients were divided into the selective amygdalohippocampectomy (SA, n = 40) and ATL (n = 42) groups. Postoperative seizure outcomes were assessed at 1, 2, 3, 5, and 7 years postoperatively using the International League Against Epilepsy classification. The Kaplan-Meier survival analysis was applied to evaluate the period of seizure recurrence between the SA and ATL groups. Factors attributed to seizure recurrence were analyzed using the Cox proportional hazards model, and they were as follows: epileptic focal laterality; age at seizure onset (< 10 or ≥ 10 years old); seizure frequency (more than weekly or less than weekly seizures); history of focal to bilateral tonic-clonic seizure; infectious etiology; and surgical procedure. The Wechsler Memory Scale–Revised was used to evaluate memory function pre- and postoperatively.

RESULTS

Seizure outcomes were significantly worse in the SA group than in the ATL group at 2 years postoperatively (p = 0.045). The International League Against Epilepsy class 1 outcomes at 7 years postoperatively in the SA and ATL groups were 63% and 81%, respectively. Kaplan-Meier analysis showed that seizure recurred significantly earlier in the SA group than in the ATL group (p = 0.031). The 2-way ANOVA analysis was used to compare the SA and ATL groups in each memory category, and revealed that there was no significant difference regardless of the side of surgery.

CONCLUSIONS

Visual assessment of ioECoG cannot be used as an indicator to minimize epileptic focus resection in patients with TLE associated with HS. ATL is more effective in obtaining seizure-free outcomes; however, both ATL and SA can preserve memory function.

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Rajeev D. Sen, Isaac Josh Abecassis, Jason Barber, Michael R. Levitt, Louis J. Kim, Richard G. Ellenbogen, and Laligam N. Sekhar

OBJECTIVE

Brain arteriovenous malformations (bAVMs) most commonly present with rupture and intraparenchymal hemorrhage. In rare cases, the hemorrhage is large enough to cause clinical herniation or intractable intracranial hypertension. Patients in these cases require emergent surgical decompression as a life-saving measure. The surgeon must decide whether to perform concurrent or delayed resection of the bAVM. Theoretical benefits to concurrent resection include a favorable operative corridor created by the hematoma, avoiding a second surgery, and more rapid recovery and rehabilitation. The objective of this study was to compare the clinical and surgical outcomes of patients who had undergone concurrent emergent decompression and bAVM resection with those of patients who had undergone delayed bAVM resection.

METHODS

The authors conducted a 15-year retrospective review of consecutive patients who had undergone microsurgical resection of a ruptured bAVM at their institution. Patients presenting in clinical herniation or with intractable intracranial hypertension were included and grouped according to the timing of bAVM resection: concurrent with decompression (hyperacute group) or separate resection surgery after decompression (delayed group). Demographic and clinical characteristics were recorded. Groups were compared in terms of the primary outcomes of hospital and intensive care unit (ICU) lengths of stay (LOSs). Secondary outcomes included complete obliteration (CO), Glasgow Coma Scale score, and modified Rankin Scale score at discharge and at the most recent follow-up.

RESULTS

A total of 35/269 reviewed patients met study inclusion criteria; 18 underwent concurrent decompression and resection (hyperacute group) and 17 patients underwent emergent decompression only with later resection of the bAVM (delayed group). Hyperacute and delayed groups differed only in the proportion that underwent preresection endovascular embolization (16.7% vs 76.5%, respectively; p < 0.05). There was no significant difference between the hyperacute and delayed groups in hospital LOS (26.1 vs 33.2 days, respectively; p = 0.93) or ICU LOS (10.6 vs 16.1 days, respectively; p = 0.69). Rates of CO were also comparable (78% vs 88%, respectively; p > 0.99). Medical complications were similar in the two groups (33% hyperacute vs 41% delayed, p > 0.99). Short-term clinical outcomes were better for the delayed group based on mRS score at discharge (4.2 vs 3.2, p < 0.05); however, long-term outcomes were similar between the groups.

CONCLUSIONS

Ruptured bAVM rarely presents in clinical herniation requiring surgical decompression and hematoma evacuation. Concurrent surgical decompression and resection of a ruptured bAVM can be performed on low-grade lesions without compromising LOS or long-term functional outcome; however, the surgeon may encounter a more challenging surgical environment.

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Marie-Jacqueline Reisener, Alexander P. Hughes, Ichiro Okano, Jiaqi Zhu, Artine Arzani, Julianna Kostas, Jennifer Shue, Andrew A. Sama, Frank P. Cammisa, Federico P. Girardi, and Ellen M. Soffin

OBJECTIVE

Opioid stewardship programs combine clinical, regulatory, and educational interventions to minimize inappropriate opioid use and prescribing for orthopedic and spine surgery. Most evaluations of stewardship programs quantify effects on prescriber behavior, whereas patient-relevant outcomes have been relatively neglected. The authors evaluated the impact of an opioid stewardship program on perioperative opioid consumption, prescribing, and related clinical outcomes after multilevel lumbar fusion.

METHODS

The study was based on a retrospective, quasi-experimental, pretest-posttest design in 268 adult patients who underwent multilevel lumbar fusion in 2016 (preimplementation, n = 141) or 2019 (postimplementation, n = 127). The primary outcome was in-hospital opioid consumption (morphine equivalent dose [MED], mg). Secondary outcomes included numeric rating scale pain scores (0–10), length of stay (LOS), incidence of opioid-induced side effects (gastrointestinal, nausea/vomiting, respiratory, sedation, cognitive), and preoperative and discharge prescribing. Outcomes were measured continuously during the hospital admission. Differences in outcomes between the epochs were assessed in bivariable (Wilcoxon signed-rank or Fisher’s exact tests) and multivariable (Wald’s chi-square test) analyses.

RESULTS

In bivariable analyses, there were significant decreases in preoperative opioid use (46% vs 28% of patients, p = 0.002), preoperative opioid prescribing (MED 30 mg [IQR 20–60 mg] vs 20 mg [IQR 11–39 mg], p = 0.003), in-hospital opioid consumption (MED 329 mg [IQR 188–575 mg] vs 199 mg [100–372 mg], p < 0.001), the incidence of any opioid-related side effect (62% vs 50%, p = 0.03), and discharge opioid prescribing (MED 90 mg [IQR 60–135 mg] vs 60 mg [IQR 45–80 mg], p < 0.0001) between 2016 and 2019. There were no significant differences in postanesthesia care unit pain scores (4 [IQR 3–6] vs 5 [IQR 3–6], p = 0.33), nursing floor pain scores (4 [IQR 3–5] vs 4 [IQR 3–5], p = 0.93), or total LOS (118 hours [IQR 81–173 hours] vs 103 hours [IQR 81–132 hours], p = 0.21). On multivariable analysis, the opioid stewardship program was significantly associated with decreased discharge prescribing (Wald’s chi square = 9.45, effect size −52.4, 95% confidence interval [CI] −86 to −19.0, p = 0.002). The number of lumbar levels fused had the strongest effect on total opioid consumption during the hospital stay (Wald’s chi square = 16.53, effect size = 539, 95% CI 279.1 to 799, p < 0.001), followed by preoperative opioid use (Wald’s chi square = 44.04, effect size = 5, 95% CI 4 to 7, p < 0.001).

CONCLUSIONS

A significant decrease in perioperative opioid prescribing, consumption, and opioid-related side effects was found after implementation of an opioid stewardship program. These gains were achieved without adverse effects on pain scores or LOS. These results suggest the major impact of opioid stewardship programs for spine surgery may be on changing prescriber behavior.

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Zhikai Hou, Long Yan, Zhe Zhang, Jing Jing, Jinhao Lyu, Ferdinand K. Hui, Weilun Fu, Ying Yu, Rongrong Cui, Min Wan, Jia Song, Yongjun Wang, Zhongrong Miao, Xin Lou, and Ning Ma

OBJECTIVE

On the basis of the characteristics of occluded segments on high-resolution magnetic resonance vessel wall imaging (MR-VWI), the authors evaluated the role of high-resolution MR-VWI–guided endovascular recanalization for patients with symptomatic nonacute intracranial artery occlusion (ICAO).

METHODS

Consecutive patients with symptomatic nonacute ICAO that was refractory to aggressive medical treatment were prospectively enrolled and underwent endovascular recanalization. High-resolution MR-VWI was performed before the recanalization intervention. The characteristics of the occluded segments on MR-VWI, including signal intensity, occlusion morphology, occlusion angle, and occlusion length, were evaluated. Technical success was defined as arterial recanalization with modified Thrombolysis in Cerebral Infarction grade 2b or 3 and residual stenosis < 50%. Perioperative complications were recorded. The characteristics of the occluded segments on MR-VWI were compared between the recanalized group and the failure group.

RESULTS

Twenty-five patients with symptomatic nonacute ICAO that was refractory to aggressive medical treatment were consecutively enrolled from April 2020 to February 2021. Technical success was achieved in 19 patients (76.0%). One patient (4.0%) had a nondisabling ischemic stroke during the perioperative period. Multivariable logistic analysis showed that successful recanalization of nonacute ICAO was associated with occlusion with residual lumen (OR 0.057, 95% CI 0.004–0.735, p = 0.028) and shorter occlusion length (OR 0.853, 95% CI 0.737–0.989, p = 0.035).

CONCLUSIONS

The high-resolution MR-VWI modality could be used to guide endovascular recanalization for nonacute ICAO. Occlusion with residual lumen and shorter occlusion length on high-resolution MR-VWI were identified as predictors of technical success of endovascular recanalization for nonacute ICAO.

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Chiman Jeon, Jung Won Choi, Doo-Sik Kong, and Hyung Jin Shin

OBJECTIVE

The purpose of this study was to investigate the efficacy and safety of endoscopic transcortical intraventricular biopsy in pediatric patients with isolated thickened pituitary stalk lesions.

METHODS

From 1994 to 2018, 16 pediatric patients (8 males and 8 females) underwent endoscopic transcortical intraventricular biopsy at a single institution to establish an accurate pathological diagnosis for appropriate treatment strategies.

RESULTS

Preoperatively, the median diameter of the pituitary stalks was 5.31 ± 1.67 mm (range 3.86–9.17 mm). Overall, the diagnostic yield at endoscopic intraventricular biopsy was 93.8%. Histopathological diagnosis included germinoma (n = 10, 62.5%), Langerhans cell histiocytosis (n = 4, 25%), pilocytic astrocytoma (n = 1, 6.3%), and pituicytoma (n = 1, 6.3%). Two patients developed new diabetes insipidus after the procedure, and 3 patients had new postoperative hypothyroidism. There were no postoperative neurological deficits in this series.

CONCLUSIONS

Neuroendoscopic biopsy via the transcortical intraventricular corridor was shown to be safe and to aid in a reliable histopathological diagnosis in the management of isolated pituitary stalk lesions in pediatric patients. It can be considered a minimally invasive alternative to open biopsy via transcranial or endonasal corridors.

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Mitsuhiro Takemura, Masanori Sasaki, Yuko Kataoka-Sasaki, Ryo Kiyose, Hiroshi Nagahama, Shinichi Oka, Ryo Ukai, Takahiro Yokoyama, Jeffery D. Kocsis, Tetsuya Ueba, and Osamu Honmou

OBJECTIVE

Stroke is a major cause of long-term disability, and there are few effective treatments that improve function in patients during the chronic phase of stroke. Previous research has shown that single systemic infusion of mesenchymal stem cells (MSCs) improves motor function in acute and chronic cerebral ischemia models in rats. A possible mechanism that could explain such an event includes the enhanced neural connections between cerebral hemispheres that contribute to therapeutic effects. In the present study, repeated infusions (3 times at weekly intervals) of MSCs were administered in a rat model of chronic stroke to determine if multiple dosing facilitated plasticity in neural connections.

METHODS

The authors induced middle cerebral artery occlusion (MCAO) in rats and, 8 weeks thereafter, used them as a chronic stroke model. The rats with MCAO were randomized and intravenously infused with vehicle only (vehicle group); with MSCs at week 8 (single administration: MSC-1 group); or with MSCs at weeks 8, 9, and 10 (3 times, repeated administration: MSC-3 group) via femoral veins. Ischemic lesion volume and behavioral performance were examined. Fifteen weeks after induction of MCAO, the thickness of the corpus callosum (CC) was determined using Nissl staining. Immunohistochemical analysis of the CC was performed using anti-neurofilament antibody. Interhemispheric connections through the CC were assessed ex vivo by diffusion tensor imaging.

RESULTS

Motor recovery was better in the MSC-3 group than in the MSC-1 group. In each group, there was no change in the ischemic volume before and after infusion. However, both thickness and optical density of neurofilament staining in the CC were greater in the MSC-3 group, followed by the MSC-1 group, and then the vehicle group. The increased thickness and optical density of neurofilament in the CC correlated with motor function at 15 weeks following induction of MCAO. Preserved neural tracts that ran through interhemispheric connections via the CC were also more extensive in the MSC-3 group, followed by the MSC-1 group and then the vehicle group, as observed ex vivo using diffusion tensor imaging.

CONCLUSIONS

These results indicate that repeated systemic administration of MSCs over 3 weeks resulted in greater functional improvement as compared to single administration and/or vehicle infusion. In addition, administration of MSCs is associated with promotion of interhemispheric connectivity through the CC in the chronic phase of cerebral infarction.

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Esmaeil Mohammadi, Sina Azadnajafabad, Mehrdad Goudarzi, Keyvan Tayebi Meybodi, Farideh Nejat, and Zohreh Habibi

OBJECTIVE

Guidelines recommend antimicrobial prophylaxis (AMP) preoperatively for "clean" spinal and cranial surgeries, while dose and timing remain controversial. The use of multiple-dose AMP for such surgeries is under debate in the pediatric context. In this clinical study, the authors aimed to compare single-dose with multiple-dose prophylactic antibiotic usage in cranial and spinal neurosurgical interventions of pediatric patients.

METHODS

All neurosurgical patients aged 28 days to 18 years who underwent surgery at a single tertiary center were assessed. Three cohorts (noninstrumented clean spinal, noninstrumented cranial, and instrumented cranial interventions), each of which comprised two 50-patient arms (i.e., single-dose AMP and multiple-dose AMP), were included after propensity score–matched retrospective sampling and power analysis. Records were examined for surgical site infections. Using a previously published meta-analysis as the prior and 80% acceptance of equivalence (margin of OR 0.88–1.13), logistic regression was carried out for the total cohort and each subcohort and adjusted for etiology by consideration of multiple-dose AMP as reference.

RESULTS

The overall sample included 300 age- and sex-matched patients who were evenly distributed in 3 bi-arm cohorts. There was no statistical intercohort difference based on etiology or type of operation (p < 0.05). Equivalence analysis revealed nondiscriminating results for the total cohort (adjusted OR 0.65, 95% CI 0.27–1.57) and each of the subcohorts (noninstrumented clean spinal, adjusted OR 0.65, 95% CI 0.12–3.44; noninstrumented cranial, adjusted OR 0.52, 95% CI 0.14–2.73; and instrumented cranial, adjusted OR 0.68, 95% CI 0.13–3.31).

CONCLUSIONS

No significant benefit for multiple-dose compared with single-dose AMPs in any of the pediatric neurosurgery settings could be detected. Since unnecessary antibiotic use should be avoided as much as possible, it seems that usage of single-dose AMP is indicated.

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Syed Hassan A. Akbari, Asad A. Rizvi, Travis S. CreveCoeur, Rowland H. Han, Jacob K. Greenberg, James Torner, Douglas L. Brockmeyer, John C. Wellons III, Jeffrey R. Leonard, Francesco T. Mangano, James M. Johnston, Manish N. Shah, Bermans J. Iskandar, Raheel Ahmed, Gerald F. Tuite, Bruce A. Kaufman, David J. Daniels, Eric M. Jackson, Gerald A. Grant, Alexander K. Powers, Daniel E. Couture, P. David Adelson, Tord D. Alden, Philipp R. Aldana, Richard C. E. Anderson, Nathan R. Selden, Karin Bierbrauer, William Boydston, Joshua J. Chern, William E. Whitehead, Robert C. Dauser, Richard G. Ellenbogen, Jeffrey G. Ojemann, Herbert E. Fuchs, Daniel J. Guillaume, Todd C. Hankinson, Brent R. O’Neill, Mark Iantosca, W. Jerry Oakes, Robert F. Keating, Paul Klimo Jr., Michael S. Muhlbauer, J. Gordon McComb, Arnold H. Menezes, Nickalus R. Khan, Toba N. Niazi, John Ragheb, Chevis N. Shannon, Jodi L. Smith, Laurie L. Ackerman, Andrew H. Jea, Cormac O. Maher, Prithvi Narayan, Gregory W. Albert, Scellig S. D. Stone, Lissa C. Baird, Naina L. Gross, Susan R. Durham, Stephanie Greene, Robert C. McKinstry, Joshua S. Shimony, Jennifer M. Strahle, Matthew D. Smyth, Ralph G. Dacey Jr., Tae Sung Park, and David D. Limbrick Jr.

OBJECTIVE

The goal of this study was to assess the social determinants that influence access and outcomes for pediatric neurosurgical care for patients with Chiari malformation type I (CM-I) and syringomyelia (SM).

METHODS

The authors used retro- and prospective components of the Park-Reeves Syringomyelia Research Consortium database to identify pediatric patients with CM-I and SM who received surgical treatment and had at least 1 year of follow-up data. Race, ethnicity, and insurance status were used as comparators for preoperative, treatment, and postoperative characteristics and outcomes.

RESULTS

A total of 637 patients met inclusion criteria, and race or ethnicity data were available for 603 (94.7%) patients. A total of 463 (76.8%) were non-Hispanic White (NHW) and 140 (23.2%) were non-White. The non-White patients were older at diagnosis (p = 0.002) and were more likely to have an individualized education plan (p < 0.01). More non-White than NHW patients presented with cerebellar and cranial nerve deficits (i.e., gait ataxia [p = 0.028], nystagmus [p = 0.002], dysconjugate gaze [p = 0.03], hearing loss [p = 0.003], gait instability [p = 0.003], tremor [p = 0.021], or dysmetria [p < 0.001]). Non-White patients had higher rates of skull malformation (p = 0.004), platybasia (p = 0.002), and basilar invagination (p = 0.036). Non-White patients were more likely to be treated at low-volume centers than at high-volume centers (38.7% vs 15.2%; p < 0.01). Non-White patients were older at the time of surgery (p = 0.001) and had longer operative times (p < 0.001), higher estimated blood loss (p < 0.001), and a longer hospital stay (p = 0.04). There were no major group differences in terms of treatments performed or complications. The majority of subjects used private insurance (440, 71.5%), whereas 175 (28.5%) were using Medicaid or self-pay. Private insurance was used in 42.2% of non-White patients compared to 79.8% of NHW patients (p < 0.01). There were no major differences in presentation, treatment, or outcome between insurance groups. In multivariate modeling, non-White patients were more likely to present at an older age after controlling for sex and insurance status (p < 0.01). Non-White and male patients had a longer duration of symptoms before reaching diagnosis (p = 0.033 and 0.004, respectively).

CONCLUSIONS

Socioeconomic and demographic factors appear to influence the presentation and management of patients with CM-I and SM. Race is associated with age and timing of diagnosis as well as operating room time, estimated blood loss, and length of hospital stay. This exploration of socioeconomic and demographic barriers to care will be useful in understanding how to improve access to pediatric neurosurgical care for patients with CM-I and SM.

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Rebecca Ronsley, Eric Bouffet, Peter Dirks, James Drake, Abhaya Kulkarni, and Ute Bartels

OBJECTIVE

The objective of this study was to describe the management of hydrocephalus in a cohort of pediatric patients with germinoma.

METHODS

The authors conducted a retrospective chart review of patients with germinoma and symptomatic hydrocephalus treated at the Hospital for Sick Children between 2002 and 2020. Descriptive data included tumor location, CSF diversion procedure (external ventricular drain [EVD], endoscopic third ventriculostomy [ETV], ventriculoperitoneal [VP] shunt) and outcomes. The frontooccipital horn ratio (FOR) method was used to determine the presence of ventriculomegaly.

RESULTS

Of 39 patients with germinoma, 22 (73% male) had symptomatic hydrocephalus at diagnosis (11 pineal, 4 suprasellar, and 7 bifocal). Management of hydrocephalus included EVD (n = 5, 22.7%), ETV (n = 5, 22.7%), and combination ETV and EVD (n = 7, 31.8%), whereas 5 patients (22.7%) did not undergo surgical intervention. The median FOR at diagnosis was 0.42 (range 0.38–0.58), which correlated with moderate to severe ventriculomegaly. Carboplatin and etoposide–based chemotherapy induced fast tumor shrinkage, avoiding CSF diversion (n = 5) and resolving hydrocephalus with a transient EVD (n = 5). The median duration until EVD removal was 7 days (range 2–10 days). Two of 12 patients with EVD ultimately required a VP shunt. Kaplan-Meier overall survival was 100% and progression-free survival was 96.4% at a median follow-up of 10.4 years.

CONCLUSIONS

Timely initiation of chemotherapy is imperative to rapidly reduce tumor bulk in children with germinoma and limits the need for VP shunt insertions. In children in whom CSF diversion is required, hydrocephalus may be successfully managed with a temporary EVD ± ETV.

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Vijay Letchuman, Nitin Agarwal, Valli P. Mummaneni, Michael Y. Wang, Saman Shabani, Arati Patel, Joshua Rivera, Alexander F. Haddad, Vivian Le, Joyce M. Chang, Dean Chou, Seema Gandhi, and Praveen V. Mummaneni

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.