Colorectal Quiz Episode 33: Cloaca Exstrophy

Prenatal imaging clues for cloacal exstrophy include small bladder and sacral dysgenesis on ultrasound and MRI.

Cloacal exstrophy is the most complicated condition managed in the colorectal world and requires collaboration with urology and gynecology.

Patients with cloacal exstrophy almost always need a neurosurgeon in addition to colorectal surgery, urology, gynecology, and orthopedics.

Like any anorectal malformation, cloacal exstrophy is not an emergency; surgeons have 24 to 48 hours to complete workup and decide on operative plan.

Preoperative workup for cloacal exstrophy includes echocardiogram to rule out congenital cardiac anomalies, spinal ultrasound, and abdominal ultrasound to assess kidneys.

Stool can often be seen coming out from the fecal plate or ileum in cloacal exstrophy, so there is not always a component of obstruction or dilated bowel loops.

NICU management priorities for cloacal exstrophy include preventing fluid losses and dehydration by using plastic covering (such as saran wrap) over the hemi-bladders and exposed tissues.

Antibiotics are not indicated for cloacal exstrophy unless there is a maternal-neonatal indication.

The best time to bring the pelvis together in cloacal exstrophy is within the first 2 to 3 days because there is enough maternal relaxin on board.

Two major surgical decision points in cloacal exstrophy are: (1) whether the omphalocele is large or small enough to close the abdominal wall, and (2) the staging of the exstrophy procedure—whether to just bring bladder plates together in a multi-stage approach or to close the bladder and bring the symphysis pubis together.

Placing catheters into every orifice helps delineate the anatomy intraoperatively in cloacal exstrophy.

The fecal plate in cloacal exstrophy contains more colon downstream from the cecum; it is not the end of the bowel.

Performing an ileostomy and leaving behind a blind-ending fecal plate and hindgut creates a situation similar to a colonic atresia in the deep pelvis, which is a surgical error.

The traditional approach to cloacal exstrophy is to extract the fecal plate from within the two hemi-bladders, tubularize it, and bring out the end of the hindgut as an end colostomy.

The overriding principle in cloacal exstrophy management is bowel preservation, as small intestine can be shortened and some patients have long-term nutritional concerns.

The traditional reason for separating the fecal plate from hemi-bladders was to avoid absorption of urine into the fecal plate and resulting acidosis.

Patients with colonic mucosa absorbing urine (e.g., bladder augmentation situations) often do not develop acidosis, making this concern less relevant.

Tubularized fecal plate can be a boggy, fairly useless piece of bowel where stool sits before emptying through the hindgut, and can contribute to recurrent bacteremia.

A newer approach leaves the fecal plate between the hemi-bladders as an auto-augmentation for the bladder, connects the distal ileum to the hindgut as a primary anastomosis, and either creates an end stoma or performs an early pull-through to the anus with ileostomy diversion.

When separating the ileum from the fecal plate to perform ileal-hindgut anastomosis, the hole in the fecal plate is oversewn.

One reason for not performing early pull-through in cloacal exstrophy is concern about rash and managing a perineal stoma.

The decision to perform early pull-through should be based on the amount of hindgut present; patients with enough hindgut (e.g., entire right colon) can develop thick enough stool for pull-through.

If a patient cannot develop thickened stool, they should never have a pull-through.

The mesentery in cloacal exstrophy can be confusing and problematic; mobilizing the hindgut up and out of the pelvis risks losing the hindgut, which would result in a permanent ileostomy.

If the hindgut can be mobilized easily without compromising the mesentery, an end stoma in the right or left lower quadrant is the preferred approach.

In the presented case, posterior and anterior osteotomies were performed to bring the pubic symphysis together, which influenced the decision to proceed with abdominal closure.

Performing the hindgut pull-through to the anus in the newborn period avoids having to re-enter the pelvis later in life, which is a difficult surgical experience.

When performing a pull-through with proximal diversion, a loop ileostomy can be created to allow some passage across and refeeding of the distal segment.

A purse-string closure of the distal segment can be used temporarily and removed in the future when everything has healed.

Refeeding the distal segment helps the skin tolerate stool until the ileostomy can be closed.

It is important that urology does not manage the bladder independent of the decision to pull through the colon; sequential procedures (bladder augmentation, Mitrofanoff, bladder neck closure at age 5 without considering colonic pull-through) make future reconstruction very difficult.

Spending extra time in the newborn period to reconstruct the hindgut and vagina can save significant work later, especially in patients whose anatomy allows for comprehensive reconstruction.

Leaving the cecal plate on the bladder makes later Mitrofanoff creation easier because the appendix is already connected and easy to bring up.