Academic OB/GYN Cases: Abdominal Cerclage How-To
I had the opportunity to do an abdominal cerclage with one of my MFM colleagues this week, which was fantastic. This is a procedure that is rarely done, and for me is something pretty new. I had the opportunity to do a few of these in residency, but hadn’t done one for over 5 years and never in a pregnant woman, so that was a great envelope-pushing experience for me.
For my colleagues that haven’t had the opportunity to do one of these procedures, I want to lay out how its done. In short, the goal is to place a cerclage between the ascending and descending branches of the uterine arteries, at the connection of the lower uterine segment and internal cervical os. When you’re done it should look something like this –
So here’s how to do it
1 – start with a woman with an indication. Several previous second trimester losses with at least one failed transvaginal cerclage.
2 – Create a transverse incision with Pfanenstiel fascial entry.
3 – Place a retractor. In this case we used an O’Connor O’Sullivan, but a Balfour will also work. An Alexis retractor may not work as well as it is harder to get behind the uterus without the upper blade holding back the bowel and fascia. In a non-pregnant uterus is easier because you can be more aggressive about moving around the uterus for access.
4 – In a pregnant uterus, be careful with it. Try not to compress the fundus, as one is potentially pushing the pregnancy down through a presumed incompetent cervix. A spongestick pushing _up_ on the lower uterine segment is a good way to get exposure.
5 – Open the vesicouterine reflection and start making a bladder flap. In a pregnant uterus this will bleed more than in a non-pregnant hysterectomy. Hemoclips are useful for occluding the thicker vessels prior to transecting them. Use blunt dissection with a peanut / Kirschner.
6 – Reach behind the uterus and feel behind the cervix. Massage the posterior peritoneum laterally at the level of the internal os, pushing the uterine arteries laterally.
7 – Identify the uterine artery on one side visually, noting the bifurcation of the ascending and desceding branches. Identify a free space between the bifurcation and the cervix.
8 – Note the ureter lateral to the interal os. When you put the uterus on stretch the ureter will be just lateral to the birfurcation, running under the uterine artery. With adequate stretch the ureter will pop up through the peritoneum and be very visible / palpable. If you can’t see it you can strum it on the lateral sidewall lateral to the uterine artery bifurcation – it will pop like a guitar string.
9 – Put a 5 mm mersilene tape between the jaws of a right angle retractor. Reach the right angle behind the cervix and then along the cervix lateral to the free space you identified. Wiggle the right angle up through the peritoneum until you can cut through the peritoneum above it. Grab the mersilene with a snap and carefully pull the right angle back. All pressure should be in pulling the tape _medially_ as lateral pressure will drag the mersilene against the uterine artery, which is to be avoided.
10 – At this point you may have bleeding from the hole you just made. Slowly bring the mersilene up and hold it with pressure against the cervix, which should slow the bleeding as long as its venous.
11 – Repeat on the other side.
12 – Tie the mersilene anteriorly with 6+ knots. Sew the ends together with a small prolene or silk, and then cut the ends off.
13 – If pregnant, confirm that the pregnancy is still viable.
14 – Close. As the patient will be having a cesarean in the near future, placement of a antiadhesion barrier is worth considering. I use SepraFilm for this.
Here’s another photo with the uterine arteries marked:
This procedure can also be performed laparoscopically both in and out of pregnancy, as described in several recent articles.