Predictive Factors of Difficult Spinal Anesthesia

Abstract

Introduction: Spinal anesthesia was a commonly used anesthetic technique in surgical procedures, but its administration was often challenging in certain patients.

Methods: This study employed a prospective analytical observational design with a cross-sectional approach, involving 418 patients who underwent spinal anesthesia procedures at Dr. Sardjito General Hospital between October 2024 and January 2025. The analyzed variables included age, BMI, history of previous spinal injections, history of spinal surgery, visibility of the spinous process, palpability of the spinous process, lumbar anatomical abnormalities, and interspinous L3-4/L4-5 characteristics. The data were analyzed using the Chi-Square test and logistic regression.

Results: Logistic regression analysis indicated that poor visibility of the spinous process increased the likelihood of difficulty by 2.21 times (P<0.01; OR 2.21; CI 1.40-3.47), lumbar anatomical abnormalities increased the likelihood by 1.87 times (P=0.01; OR 1.87; CI 1.16-3.02), and the L3-4 interspinous space was 2.08 times more difficult to access compared to the L4-5 interspinous space (P<0.01; OR 2.08; CI 1.32-3.28). Although significant results were observed in the bivariate analysis, high BMI, moderate BMI, history of repeated spinal injections, and spinous process palpability did not demonstrate an independent effect on procedural difficulty.

Discussion: Factors such as poor spinous process visibility, lumbar anatomical abnormalities, and interspinous L3-4/L4-5 characteristics were found to be associated with difficulties in spinal anesthesia administration. These findings were consistent with previous studies indicating that spinous process visibility, lumbar anatomical abnormalities, and interspinous characteristics influenced the success of spinal anesthesia.