Positioning obese patients for minimally invasive gynecologic surgery

The current epidemic of obesity presents gynecologic surgeons with the challenge of safely and successfully performing minimally invasive surgery in women who are morbidly or superobese.

In 2004, the prevalence of a body mass index greater than 40 kg/m² was almost 7.0% in females in the United States (JAMA. 2006 Apr 5;295[13]:1549-55.). Most recently, 8.3% of women were reported to have a BMI greater than 40 (JAMA. 2014 Feb 26;311[8]:806-14.). This is a value that the World Health Organization defines as Class III obesity and that, according to further stratification reported in the surgical literature, includes the categories of morbid obesity (40-44.9), superobesity (greater than 45), and super-superobesity (greater than 60).

Dr. Amina Ahmed

As a gynecologic oncologist, I see firsthand the impact of obesity on the risk of multiple gynecologic conditions and female cancers, including endometrial cancer, as well as the benefits of a minimally invasive approach. I frequently perform hysterectomies via the minimally invasive approach to treat precancer and cancer of the uterus in morbidly and superobese women who have significant central adiposity.

MIGS benefits in the obese

In the past 15 years, and particularly in the past decade, evidence that obese patients benefit from laparoscopic surgery compared with traditional laparotomy has increased. I consider minimally invasive surgery the standard of care for women with endometrial cancer, regardless of the BMI.

As Dr. Stacey A. Scheib and her colleagues wrote in a recent review on laparoscopy in the morbidly obese, most of the gynecologic literature comparing laparoscopic surgery with laparotomy in this population is focused on gynecologic oncology because obesity is so strongly associated with endometrial and other cancers in women (J Minim Invasive Gynecol. 2014 Mar-Apr;21[2]:182-95.). In one prospective study of women with clinical stage I endometrial cancer and BMIs between 28 and 60, those who underwent laparoscopic surgery – 40 of 42 women over 2 years – had significantly longer operative times but less operative morbidity, shorter hospital stays, faster recovery and better postsurgical quality of life, compared with women who had undergone laparotomy in the previous 2 years. The control patients also had clinical stage I endometrial cancer and similar BMIs (Gynecol Oncol. 2000 Sep;78[3 Pt 1]:329-35.).

Research comparing robotics and conventional laparoscopy in obese gynecologic surgery patients is limited, and findings are inconsistent. It will remain difficult to compare the two approaches because few surgeons are equally skilled in both approaches and because the learning curve for conventional laparoscopy is so much steeper than for robotics.

I favor the robotic approach for morbidly and superobese patients for its superior visualization and ergonomics.

Patient positioning

It is important to use an operative bed that will accommodate the weight and width of obese patients and enable Trendelenburg positioning of up to 45 degrees. We use a bariatric bed with a 1,000-pound weight limit.

Obese patients are at greater risk for neuromuscular injuries and pressure sores, so careful patient positioning and padding of pressure points is critically important. We have found a surgical bean bag to be much more effective in preventing slippage for the morbidly or superobese patient than is egg-crate foam. The bean bag conforms nicely to the shape of the patient’s back, neck, and arms when it is appropriately desufflated. After desufflation, the bean bag must be well taped onto the operative bed.

I sometimes use shoulder blocks for extra assurance. When used, these braces must be attached to the bean bag and not to the patient.

We typically pad the arms completely with gel pads or foam before the bean bag is desufflated. We also often pad the knees and calves before the legs are placed and secured in stirrups made for the morbidly obese, with the buttocks slightly off the table.

In a review of literature on obesity and laparoscopy outcomes, Dr. Georgine Lamvu and her associates recommended that the arms be tucked in the “military” position, along the length of the body (Am J Obstet Gynecol. 2004 Aug;191[2]:669-74.). To ensure that both arms are properly tucked against the length of the body, we use bed extenders or sleds to widen the bed as necessary.

Abdominal access

I use the open Hasson technique in my obese patients and enter the peritoneum under direct visualization. In patients with high levels of morbid obesity, I have found it helpful to retract the adipose tissue using thin Breisky vaginal retractors. These retractors can hold the adipose tissue away from the fascia to facilitate entry into the abdominal cavity via the open technique.

Utilizing the umbilicus as the initial entry point – often desirable in minimally invasive surgery – is frequently not possible in morbidly obese patients because as BMI increases, the umbilicus migrates toward the pubic bone and away from the aortic bifurcation. In patients who were overweight (BMI greater than 25), Dr. W.W. Hurd and his associates noted a repositioning of the umbilicus below the aortic bifurcation of 2 cm or greater (Obstet Gynecol. 1992 Jul;80[1]:48-51.).