Date Published: June 13, 2019
Publisher: Public Library of Science
Author(s): Hao Deng, Jean-Valery Coumans, Richard Anderson, Timothy T. Houle, Robert A. Peterfreund, Panagiotis Kerezoudis.
Anesthesiologists at our hospital commonly administer spinal anesthesia for routine lumbar spine surgeries. Anecdotal impressions suggested that patients received fewer anesthesia–administered intravenous medications, including vasopressors, during spinal versus general anesthesia. We hypothesized that data review would confirm these impressions. The objective was to test this hypothesis by comparing specific elements of spinal versus general anesthesia for 1–2 level open lumbar spine procedures.
Retrospective single institutional study.
Academic medical center, operating rooms.
Consecutive patients (144 spinal and 619 general anesthesia) identified by automatic structured query of our electronic anesthesia record undergoing lumbar decompression, foraminotomy or microdiscectomy by one surgeon under general or spinal anesthesia.
Spinal or general anesthesia.
Numbers of medications administered during the case.
Anesthesiologists administered in the operating room a total of 10 ± 2 intravenous medications for general anesthetics and 5 ± 2 medications for spinal anesthetics (-5, 95% CI -5 to -4, p<0.001, univariate analysis). Multivariable analysis supported this finding (spinal versus general anesthesia: -4, 95% CI -5 to -4, p<0.001). Spinal anesthesia patients were less likely to receive ephedrine, or phenylephrine (by bolus or by infusion) (all p<0.001, Chi-squared test). Spinal anesthesia patients were also less likely to receive labetolol or esmolol (both p = 0.002, Fishers’ Exact test). No neurologic injuries were attributed to, or masked by, spinal anesthesia. Three spinal anesthetics failed. For routine lumbar surgery in our cohort, spinal compared to general anesthesia was associated with significantly fewer drugs administered during a case and less frequent use of vasoactive agents. Safety implications include greater hemodynamic stability with spinal anesthesia along with reduced risks for medication error and transmission of pathogens associated with medication administration.
Surgical procedures on the lumbar spine include discectomy, foraminotomy, synovial cyst removal, decompression, and several types of fusions. Patients typically receive general anesthesia (GA) for these procedures. However, several primary clinical research publications describe administering spinal anesthesia (SA) for lumbar spine surgery [1–21]. Recent review articles [22–25] summarize the data from these primary reports. Some of the published studies contain comparisons between GA and SA for various hemodynamic parameters.
The Partners Healthcare Institutional Review Board approved this study (Number: 2016P002684). Informed consent was not required due to the retrospective cohort nature of study design.
A total of 763 consecutive cases were identified for this study, with 619 patients in the GA group and 144 patients in the SA group. Demographic data appear in Table 1. The distribution of surgical procedures was similar between the SA and GA groups (Table 2, Chi-squared test p = 0.717).
Our findings confirm and extend the observations of other investigators. For selected patients, for specific lumbar spine surgeries, SA may be a reasonable option. Possible safety advantages include reduced number of different drugs administered during SA, thereby lessening potentials for medication error, adverse drug-drug interactions and postoperative infections attributable to administering intravenous medications. Other advantages include apparent hemodynamic stability and reduced OR time. Results appear to be consistent despite the number of independent providers and the absence of clinical protocols, suggesting that the observations reflect real world practice.