MRI Based Prediction of Difficult Neuraxial Anesthesia in Obese Women Undergoing Gynecologic Surgery

Abstract

Background: Gynecological operations often need the use of neuraxial anesthesia. Due to increased subcutaneous tissue, difficult-to-identify anatomical landmarks, and a larger skin-to-epidural distance, obesity may make the procedure more challenging.

Objective: The aim of this study was to find out MRI based prediction of difficult Neuraxial anesthesia in obese women undergoing gynecologic surgery

Material and Methods: The present prospective observational study was conducted at Gyanae / OBS Department Lady Reading Hospital Peshawar and Radiology Department Gomal medical college D I Khan from April 2023 to July 2023 to following approval from the ethical committee of the institute. A total of 150 obese (BMI of 30 kg/m² or above ) women of different age groups with, planned for elective gynecological surgery with neuraxial anesthesia  and Patients who had  done  lumbar MRI before  surgery were included in this study. Data including, weight, age, medical history, previous history of difficult neuraxial anesthesia and BMI were recorded. Before surgical procedure clinical examination were assessed including lumbar spine anatomy, visible spinal abnormalities, palpability of spinous processes and back flexion. Anatomical features important to neuraxial anesthesia were assessed by reviewing preoperative lumbar MRI findings. MRI measures employing a consistent measuring methodology, carried out by a radiologist who was blind to the anesthetic results. Qualified anesthesiologists used institutional guidelines to administer neuraxial anesthesia. More than two needle attempts, more than ten minutes for effective placement, or inability to finish the desired neuraxial procedure were all considered indicators of difficult neuraxial anesthesia. Successful placement within two tries and ten minutes was considered easy placement. SPSS version 20 was used for data analysis.

Results: A total of 150 obese females were undergoing gynecologic surgery were enrolled. The mean age of the study population was 40.5 ± 6.5 years and mean BMI was 35.9 ± 6.1 kg/m².  Preoperative MRI revealed several anatomical anomalies. The most frequent finding, seen in 88 (58.7%) participants, was increased subcutaneous fat thickness. 82 (54.7%) of the patients had an increased skin-to-epidural distance. 72 patients (48.0%) had poor lumbar anatomical landmark visibility, while 48 patients (32.0%) had decreased interspinous distance.42 patients (28.0%) had degenerative spinal alterations, while 30 patients (20.0%) had facet joint hypertrophy. 18 (12.0%) individuals had scoliosis or other anatomical abnormalities. Difficult neuraxial anesthesia was reported in 65 (43.3%) patients, while 85 (56.7%) patients had successful placement. Difficulty was statistically correlated with increased skin-to-epidural distance, higher subcutaneous fat thickness, decreased interspinous distance, poor lumbar landmark visibility, degenerative alterations, and scoliosis/anatomical variation.

Conclusion: Our study concluded that for obese women undergoing gynecological surgery, MRI-based anatomical evaluation may be a helpful predictor of difficult neuraxial anesthesia.

Keywords: Gynecological surgery, Obese women, MRI, difficult neuraxial anesthesia