2016 Update on minimally invasive gynecologic surgery

Rightly so, the topics of mechanical tissue extraction and hysterectomy approach have dominated the field of obstetrics and gynecology over the past 12 months and more. A profusion of literature has been published on these subjects. However, there are 2 important topics within the field of minimally invasive gynecologic surgery that deserve our attention as well, and I have chosen to focus on these for this Update.

First, laparoscopic treatment of ovarian endometriomas is one of the most commonly performed gynecologic procedures worldwide. Many women undergoing such surgery are of childbearing age and have the desire for future pregnancy. What are best practices for preserving ovarian function in these women? Two studies recently published in the Journal of Minimally Invasive Gynecology addressed this question.

Second, until recently, the rate of bowel injury at laparoscopic gynecologic surgery has not been well established.¹ Moreover, mechanical bowel preparation is commonly employed in case intestinal injury does occur, despite the lack of evidence that outcomes of these possible injuries can be improved.² Understanding the rate of bowel injury can shed light on the overall value of the perceived benefits of bowel preparation. Therefore, I examine 2 recent systematic reviews that analyze the incidence of bowel injury and the value of bowel prep in gynecologic laparoscopic surgery.

bipolar coagulation inferior to suturing or hemostatic sealant for preserving ovarian function

Song T, Kim WY, Lee KW, Kim KH. Effect on ovarian reserve of hemostasis by bipolar coagulation versus suture during laparoendoscopic single-site cystectomy for ovarian endometriomas. J Minim Invasive Gynecol. 2015;22(3):415−420.

Ata B, Turkgeldi E, Seyhan A, Urman B. Effect of hemostatic method on ovarian reserve following laparoscopic endometrioma excision; comparison of suture, hemostatic sealant, and bipolar dessication. A systematic review and meta-analysis. J Minim Invasive Gynecol. 2015;22(3):363−372.

FIGURE. The customary surgical approach for laparoscopiccystectomy to remove an endometrioma is mechanicalstripping of the cyst wall. To achieve the hemostasis afterthis process, bipolar desiccation, suturing, or a hemostaticagent can be employed. Data indicate that bipolar desiccation,when used, may significantly decrease the ovarian reserve.

The customary surgical approach for laparoscopic cystectomy is by mechanical stripping of the cyst wall (FIGURE) and the use of bipolar desiccation for hemostasis. Stripping inevitably leads to removal of healthy ovarian cortex,3 especially in inexperienced hands,⁴ and ovarian follicles inevitably are destroyed during electrosurgical desiccation. When compared with the use of suturing or a hemostatic agent to control bleeding in the ovarian defect, the use of bipolar electrosurgery may harm more of the ovarian cortex, resulting in a comparatively diminished follicular cohort.

Possible deleterious effects on the ovarian reserve can be determined with a blood test to measure anti-Müllerian hormone (AMH) levels postoperatively. Produced by the granulosa cells of the ovary, this hormone directly reflects the remaining ovarian egg supply. Lower levels of AMH have been shown to significantly decrease the success rate of in vitro fertilization (IVF), especially in women older than age 35.⁵ Moreover, AMH levels in the late reproductive years can be used as a predictive marker of menopause, with lower levels predicting significantly earlier onset.⁶

Data from 2 recent studies, a quasi-randomized trial by Song and colleagues and a systematic review and meta-analysis by Ata and colleagues emphasize that bipolar desiccation for hemostasis may not be best practice for protecting ovarian reserve during laparoscopic ovarian cystectomy for an endometrioma.

AMH levels decline more significantly for women undergoing bipolar desiccation
Song and colleagues conducted a prospective quasi-randomized study of 125 women whose endometriomas were laparoscopically removed via a single-site approach and managed for hemostasis with either bipolar desiccation or suturing of the ovarian defect with a 2-0 barbed suture. All surgeries were conducted by a single surgeon.

At 3 months postsurgery, mean AMH levels had declined from baseline by 42.2% (interquartile range [IR], 16.5−53.0 ng/mL) in the desiccation group and by 24.6% (IR, 11.6−37.0 ng/mL) in the suture group (P = .001). Multivariate analysis showed that the method used for hemostasis was the only determinant for reduced ovarian reserve.

In their systematic review and meta-analysis, Ata and colleagues included 10 studies--6 qualitative and 4 quantitative. All studies examined the rate of change of serum AMH levels 3 months after laparoscopic removal of an endometrioma.

In their qualitative analysis, 5 of the 6 studies reported a significantly greater decrease in ovarian reserve after bipolar desiccation (varying from 13% to 44%) or a strong trend in the same direction. In the sixth study, the desiccation group had a lower decline in absolute AMH level than in the other 5 studies. The authors note that this 2.7% decline was much lower than the values reported for the bipolar desiccation group of any other study. (Those declines ranged between 19% and 58%.)

Although not significant, in all 3 of the included randomized controlled trials (RCTs), the desiccation groups had a greater loss in AMH level than the hemostatic sealant groups, and in 2 of these RCTs, bipolar desiccation groups had a greater loss than the suturing groups.

Among the 213 study participants in the 3 RCTs and the prospective cohort study included in the quantitative meta-analysis, alternative methods to bipolar desiccation were associated with a 6.95% lower decrease in AMH-level decline (95% confidence interval [CI], −13.0% to −0.9%; P = .02).