Assessing the Safety and Efficacy of Spinal Anesthesia in Patients with Significant Comorbidities.

BACKGROUND: Spinal anesthesia is an effective modality for lumbar surgery. Patient eligibility with respect to medical comorbidities remains a topic of debate. Obesity (body mass index ≥30 kg/m2), anxiety, obstructive sleep apnea, reoperation at the same level, and multilevel operations have variously been reported as relative contraindications. We hypothesize that patients undergoing common lumbar surgeries with these comorbidities do not experience greater rates of complications compared with controls. METHODS: We analyzed a prospectively collected database of patients undergoing thoracolumbar surgery under spinal anesthesia and identified 422 cases. Surgeries were less than 3 hours (the duration of action of intrathecal bupivacaine) and include microdiscectomies, laminectomies, and both single-level and multilevel fusions. Procedures were performed by a single surgeon at a single academic center. In overlapping groups, 149 patients had a body mass index ≥30 kg/m2, 95 had diagnosed anxiety, 79 underwent multilevel surgery, 98 had obstructive sleep apnea, and 65 had a previous operation at the same level. The control group included 132 patients who did not have these risk factors. Differences in important perioperative outcomes were assessed. RESULTS: There were no statistically significant differences in intraoperative and postoperative complications except 2 cases of pneumonia in the anxiety group and 1 case in the reoperative group. There were also no significant differences for patients with multiple risk factors. Rates of spinal fusion were similar among groups, although mean length of stay and operative time were different. CONCLUSIONS: Spinal anesthesia is a safe option for patients with significant comorbidities and can be considered for most patients undergoing routine lumbar surgeries.

A Second Prone Dose Algorithm for Patients Undergoing Spinal Anesthesia During Thoracolumbar Surgeries.

BACKGROUND: Spinal anesthesia is safe and effective in lumbar surgeries, with numerous advantages over general anesthesia (GA). Nevertheless, 1 major concern preventing the widespread adoption of this anesthetic modality in spine surgeries is the potential for intraprocedural anesthetic failure, resulting in the need to convert to GA intraoperatively. OBJECTIVE: To present a novel additional prone dose algorithm for when a first spinal dose fails to achieve the necessary effect. METHODS: A total of 422 consecutive patients undergoing simple and complex thoracolumbar surgeries under spinal anesthesia were prospectively enrolled into our database. Data were retrospectively collected through extraction of electronic health records. RESULTS: Sixteen of 422 required a second prone dose, of whom 1 refused and was converted to GA preoperatively. After 15 were given a prone dose, only 2 required preoperative conversion to GA. There were no instances of intraoperative conversion to GA. The success rate for spinal anesthesia without the need for conversion rose from 96.4% to 99.5%. In patients who required a second prone dose, there were no instances of spinal headache, deep vein thrombosis, pneumonia, urinary tract infection, urinary retention, readmission within 30 days, acute pain service consult, return to operating room, durotomy, or cerebrospinal fluid on puncture. CONCLUSION: Use of an additional prone dose algorithm was able to achieve a 99.5% success rate, and those who received this second dose did not experience any complications or negative operative disadvantages. Further research is needed to investigate which patients are at increased risk of inadequate analgesia with spinal anesthesia.

Assessing the impact of spinal versus general anesthesia on postoperative urinary retention in elective spinal surgery patients.

OBJECTIVE: Postoperative urinary retention (POUR) is a common and vexing complication in elective spine surgery. Efficacious prevention strategies are still lacking, and existing studies focus primarily on identifying risk factors. Spinal anesthesia has become an attractive alternative to general anesthesia in elective lumbar surgery, with the potential of having a differential impact on POUR. METHODS: 422 spinal anesthesia procedures were prospectively collected between 2017 and 2021 and compared to 416 general anesthesia procedures retrospectively collected between 2014 and 2017, at a single academic center by the same senior neurosurgeon. The main outcome was POUR, defined as the need for straight bladder catheterization or indwelling bladder catheter placement after surgery due to failure to void. A power calculation was performed prior to data collection. RESULTS: The general anesthesia group had a higher rate of POUR (9.1 %) compared with the spinal anesthesia group (4.3 %), p = 0.005. At baseline, the spinal anesthesia cohort had an older average age and fewer patients with a history of previous spine surgery. Other comorbid conditions were comparable between the groups. For perioperative characteristics, spinal anesthesia patients had higher ASA scores, shorter operative times, shorter lengths of hospital stay, less operative levels, and zero use of intraoperative bladder catheterization. Acute pain service consult was similar between the groups. A multivariable logistic regression revealed that spinal anesthesia was associated with a significantly lower rate of urinary retention in the spinal anesthesia group (p = 0.0130), after adjusting for potentially confounding factors. Other statistically significant risk factors for POUR included diabetes, (p = 0.003), BPH (p = 0.014), operative time (p = 4.94e-06), and ASA score (p = 0.005). CONCLUSIONS: We collect and analyze one of the largest available cohorts of patients undergoing simple and complex surgeries under spinal and general anesthesia, finding that spinal anesthesia is independently associated with a lower incidence of POUR compared to general anesthesia, even when adjusted for potentially confounding risk factors. Further prospective trials are needed to explore this finding.

Safety and feasibility of spinal anesthesia during simple and complex lumbar spine surgery in the extreme elderly (≥80 years of age).

OBJECTIVE: The extreme elderly population (≥80 years of age) is expected to triple globally by 2050 and surgeries in this age group are likely to increase. Spinal anesthesia has emerged as a safe and effective alternative to general anesthesia in lumbar surgery and may particularly benefit extreme elderly patients concerned with post-operative cognitive dysfunction, poor physiological reserves, and polypharmacy. However, literature supporting its use in this population is lacking and there are potential challenges such as degenerative anatomy and medical comorbidities. Here, we assess the safety and feasibility of using spinal anesthesia in the extreme elderly. METHODS: Between 2017 and 2021, 424 consecutive lower thoracic and lumbar spine surgeries were performed under spinal anesthesia by a single surgeon at a large academic hospital and procedural details were collected in a prospective database. Forty-six patients were ≥ 80 years in age. Demographic, surgical, perioperative, and anesthetic data were retrospectively analyzed. RESULTS: The extreme elderly cohort had increased ASA scores, levels of surgery, and length of stay. Similar rates occurred for spinal headache, deep vein thrombosis, pneumonia, urinary tract infection, urinary retention, readmission within 30 days, acute pain service consult, return to the operating room, and durotomy. Intraoperative visualization of the spinal anesthesia dural puncture was increased in the extreme elderly (3 vs. 1 patient). CONCLUSION: We report one of the largest series of extreme elderly patients undergoing spinal anesthesia for simple and complex lumbar spine surgeries and demonstrate that spinal anesthesia can be safe and feasible in this population.

Dataset for carbon footprints of transforaminal lumbar interbody fusions performed under spinal or general anesthesia.

The datasets presented here quantify and compare the relative carbon footprints emitted by general versus spinal anesthesia in patients undergoing single-level transforaminal lumbar interbody fusions (TLIFs). Data were retrospectively collected from electronic medical records of 100 consecutive patients who underwent a single-level TLIF from a single neurosurgeon at a U.S. academic center. 50 patients were under general anesthesia, and another 50 patients were under spinal anesthesia. Clinic and operative notes were used to extract demographic and surgical information, whereas anesthesia records were used to extract anesthetic information. Using the anesthetic information, carbon dioxide equivalents (CO2e) were calculated for each type of anesthetic and summed together to compute the total carbon footprint for each patient. Our article entitled "Assessing the environmental carbon footprint of spinal versus general anesthesia in single-level transforaminal lumbar interbody fusions" is based on this data [1]. Raw datasets of the primary data collection as well as cleaned and analyzed datasets are presented. These datasets highlight the first known environmental impact calculation from medical records of a spine procedure, serving as a model for other interested investigators to explore and emulate. This data brief may help to pave the way towards future environmental research and practice changes within neurosurgical and orthopedic literature, an issue critical to the sustainability of our modern society.

Assessing the Environmental Carbon Footprint of Spinal versus General Anesthesia in Single-Level Transforaminal Lumbar Interbody Fusions.

BACKGROUND: The U.S. health care sector produces approximately 10% of national greenhouse gas emissions, paradoxically harming human health. Neurosurgery is a resource-intensive specialty that likely contributes significantly, yet literature assessing this impact is absent. We investigate the difference in carbon emissions between spinal versus general anesthesia in lumbar spine surgery. METHODS: A total of 100 patients underwent a single-level transforaminal lumbar interbody fusion (TLIF) from a single surgeon; 50 received spinal anesthesia and 50 received general anesthesia. Data were extracted from patient records. Amounts of anesthetics were calculated from intraoperative records and converted to carbon dioxide equivalents (CO2e). RESULTS: The median CO2e for general anesthesia was 4725 g versus 70 g for spinal anesthesia (P = 7.07e-18). The mean CO2e for general anesthesia was 22,707 g versus 63 g for spinal anesthesia. Desflurane use led to outsized carbon emissions. Carbon footprint comparisons are made with familiar units such as miles driven by a car, and are provided for a single TLIF, 50 TLIFs (single surgeon's cases in a year), and 488,000 TLIFs (annual spinal fusions in the United States). CONCLUSION: This is one of the first known comparative carbon footprint studies performed in neurosurgical literature. We highlight the dramatic carbon footprint reduction associated with using spinal anesthesia and reflect a single neurosurgeon's change in practice from using only general anesthesia to incorporating the use of spinal anesthesia. Within general anesthesia patients, desflurane use was particularly harmful to the environment. We hope that our study will pave the way toward future research aimed at uncovering and reducing neurosurgery's environmental impact.