AAGL 2012: Preoperative Measurements Predict Surgical Difficulty in Overweight and Obese Women

Preoperative measurement of intra-abdominal visceral fat, and the ratio of intra-abdominal visceral fat to subcutaneous fat, may help predict women at greater risk for difficulties during robotic surgery.

Jessica Hsieh, MD, et al conducted a retrospective chart review of 70 overweight or obese patients who had a CT scan prior to undergoing robotic hysterectomies. All patients had a BMI of at least 25 and underwent a robotic hysterectomy with or without bilateral salpingo-oophorectomy or lymph node dissection for a benign or malignant condition. Women who did not have preoperative imaging were excluded, as were women with ovarian cancer, adnexal mass greater than 10 centimeters, or conversion to laparotomy due to advanced disease.

Intra-abdominal visceral fat and subcutaneous fat were measured from preoperative CT scan. Surgical difficulty was the primary outcome, and was defined as conversion to laparotomy, additional laparoscopic port sites, or use of laparoscopic bowel retractor. Conversion to laparotomy, intraoperative complications, postoperative complications, and operative time were also measured.

The ratio of intra-abdominal visceral fat to subcutaneous fat was found to be a significant risk factor for surgical difficulty. Based on the Receiver Operator Characteristic (ROC), the optimal ratio to predict surgical difficulty is 4 (specificity = 75%, specificity = 88%).
A BMI greater than 33.9 was also significantly associated with surgical difficulty and conversion to laparotomy. Intra-abdominal visceral fat greater than 10 was associated with a higher rate of conversion to laparotomy as well.

“These parameters can be useful tools for preoperative counseling and planning,” said Hsieh.
Surgical difficulty was not significantly impacted by SF, IVF, age or uterine size.
IVF/SF, IVF, and BMI did not significantly impact intraoperative or postoperative complications.

Authors acknowledged potential limitations of the study, including a small number of patients, a small number of conversions, and the retrospective study design. They are currently conducting a prospective trial evaluating the utility of measuring intra-abdominal visceral fat and the ratio of intra-abdominal visceral fat to subcutaneous fat in this population.