Suprapannus caesarean birth is a rare approach that offers benefits for wound healing for women with a high BMI. Our team is based in a tertiary unit with a high baseline BMI and a community with complex health needs.
We performed an intensive series of three consecutive cases as a group to create and refine our technique and have documented our approach with surgical steps and equipment required. Each patient had a BMI higher than 60, with obesity-associated medical comorbidities and a large and mobile pannus.
There were significant advantages for the approach when utilised for the right patient. Each of the wounds were easy to access and observe on the postnatal ward, and all wounds healed well with no infection. There was a distinct anaesthetic advantage, as the mother did not need to be supine until the last moment prior to birth, which is potentially advantageous from a respiratory standpoint.
As a team, we observed and discussed some drawbacks to the technique, including some difficulties with abdominal entry and delineating anatomical locations, access issues and the requirement for a skilled operative team. We have shared our learnings here for other units looking to employ such an approach for patients in a high BMI category.
Anaesthetic Considerations
Each patient underwent anaesthetic review prior to surgery. Dual intravenous access with 2x large bore cannulae was established prior to commencing regional anaesthesia. Discussion was had regarding suitability for combined spinal/epidural or spinal anaesthetic, with one patient undergoing the former and two patients the latter. All patients had appropriate anaesthetic coverage throughout their procedures. One patient had severe obstructive sleep apnoea, requiring high flow nasal oxygenation throughout the operation due to obstruction when semi-recumbent. Prolonged antibiotics (IV Cephazolin) were given for 24 hours over the perioperative period.
Patient Positioning and Draping
Patients were positioned supine on the operating table, with the head of the bed brought up to allow them to rest at approximately 45°. Left lateral tilt was applied. Chlorhexidine 2% preparation was applied from xiphisternum to mid-thigh, including judicious preparation underneath the pannus. Disposable drapes were applied in a classical square-draping configuration. The upper drape was placed above the level of the umbilicus and the lower drape placed under the pannus and at the level of the pubic symphysis.
Incision Site
The incision site was chosen based on the requirements for each patient. Two women underwent 15cm incisions with a slight inverted curve that were placed subumbilically, which was ultimately the preferred incision site for our practitioners. However, one case was performed with a lateral 20cm incision given skin integrity issues. The incisions were discussed with the patients for location prior to surgery and marked in the theatre with a marking pen to guide entry. In the patients in this series, the surface anatomy was significantly distorted with the umbilicus being displaced inferiorly by the mobility of the pannus, with the area of incision able to be easily mobilised over the pubic symphysis.
Subcutaneous Fascia Dissection
Entry through the pannus to the level of the rectus sheath was a major challenge given the lack of normal anatomical landmarks. Thick venous pathways were encountered and individually ligated, as well as areas of thickened fibrous tissue. Monopolar diathermy was used to dissect the subcutaneous fascia.
Avoiding creating a buttonhole in the pannus or an inadvertent panniculectomy was a challenge, and we found the easiest way to trace our location was to place the forearm of one of the surgeons under the pannus so that it could be palpated and the correct direction for rectus sheath entry several centimetres above the pubic symphysis found.
In one patient, it was surprisingly difficult to recognise the rectus sheath at the point of entry given overlying fibrous tissue, and we utilised an ultrasound with a curvilinear probe and a sterile cover to ensure entry was at the correct level.
Abdominal Entry and Retraction
The rectus sheath was incised horizontally, several centimetres above the pubic symphysis. Abdominal entry was made in a modified Joel-Cohen fashion, with blunt entry of the parietal peritoneum and lateral stretching of the rectus muscles. An Alexis O C-Section Protector-Retractor in size extra-large was placed to allow clear access to the uterus but also compress the overlying pannus, which was substantially thicker than at a standard caesarean. Access to the lower segment was extremely difficult, as was lowering the bladder, due to lack of mobility in the overlying tissues and distance from the top of the wound to the lower pelvis.
Uterine Entry
Once the abdomen was opened and uterine entry imminent, the back of the bed was lowered and the patient placed in a supine position for the delivery of the baby. Uterine entry was on the upper aspect of the lower uterine segment for all women. Accessing the mid to lower portion of the lower segment would have been very difficult in each scenario and should be included for discussion and counselling if a patient is considering future vaginal birth.
Delivery
Delivery of the neonate posed some individual challenges given the depth from outer wound to the uterus, as well as difficulty in applying direct fundal pressure. Wrigley’s forceps could not be used given the depth of the pelvis and lack of room to rotate the shanks dorsally. One baby was delivered manually, however for the other two we utilised a Kiwi cup for a ventouse delivery. The smooth profile of the omni cup was able to be inserted easily into the uterus, and the baby was then able to be flexed and the head easily delivered in both circumstances.
Closure
Uterine closure was performed in two layers with one Vicryl. One patient underwent bilateral salpingectomies with Ligasure at the time of procedure. The rectus sheath was closed with one Vicryl and the subcuticular fascia was repaired in two layers of interrupted 2.0 Vicryl to ensure resolution of dead space and prevention of seroma formation. Skin was closed with 3.0 Monocryl, and a honeycomb dressing was applied over each wound.
Postnatal Course
All women recovered well on the ward and were discharged between days three and five postnatally. All wounds healed well and there was no seroma formation or wound infection in the patients in this series. Analgesia use was standard, and each patient was mobilising well at the point of discharge.
Discussion
We trialled this technique for a small cohort of women with a high BMI and a large and mobile pannus. The primary aim was to reduce wound infections and mobilise the wound to an area that is easier for the patient and caregivers to look after. None of the three patients developed a major wound infection.
The procedure itself is complex, and we would recommend two senior obstetricians be present at all times given the difficulty in achieving adequate access and identifying normal landmarks.
Patient selection is important, and the result must be cosmetically acceptable to the individual undergoing the procedure given the end result of a more visible scar on the mid abdomen. Additionally, our case series involves patients who were not at overt increased risk for postpartum haemorrhage (PPH) and had cephalic presentations. We recommend exercising caution if considering a suprapannus approach on top of other known risk factors, as haemorrhage control or delivery of an entrapped fetal head may be very difficult in this situation.
Overall, the procedure received good feedback from all involved, including patients, clinicians, and ward staff. Each patient was happy with the location of their wound in their postnatal period. Our anaesthetic colleagues found the procedure was tolerated well by each patient, as they were not supine until the last minute and did not have any compressive restrictions on ventilation such as we often see with a Traxi or similar retractor. The midwifery staff on the ward found the procedure to be greatly beneficial for monitoring the caesarean wound and keeping it clean and dry.
