This operation dates from the pre-antibiotic era, and the introduction of metronidazole (2.7) has made it largely unnecessary. But if you don't have metronidazole, and you have to operate in the presence of sepsis, you may find it useful. It is one of the more contentious operations in this book and one contributor doubts its value.
If you section a mother in the presence of intrauterine infection, or after a long labour, she runs the serious risk of multiple peritoneal abscesses or peritonitis. There is quite a chance that she will die. You can reduce the risk of peritonitis by excluding the incision in her uterus from her peritoneal cavity. To do this, reflect her parietal peritoneum from the inside of her abdominal wall, and her visceral peritoneum from the front of her lower segment, and tie them together. This will seal off her peritoneal cavity from the incision that you are about to make into her infected uterus. This takes longer than the standard method, and is not as easy as it looks, but it is worth trying, if she is badly infected.
-Fig. 18-15 EXTRAPERITONEAL CAESAREAN SECTION. A, a view of the patient's anterior abdominal wall from inside her abdomen, indicating the structures to be cut. B, artery forceps attached to her median umbilical ligament. C, her peritoneum reflected off her anterior abdominal wall. D, her peritoneum is being reflected off her lower segment. E, her peritoneum tied in a purse string. Kindly contributed by Hugh Philpott.
EXTRAPERITONEAL CAESAREAN SECTION See also Sections 18.8 and 18.11. Many of the details for the standard lower segment operation apply here also.
INDICATIONS. Any Caesarean section in which the risk of subsequent peritoneal infection is great, when you have no adequate antibiotic cover, and especially no metronidazole. In an obstructed labour the attempt to do an extraperitoneal Caesarean section may be an impractical addition to an already complicated situation.
PERIOPERATIVE ANTIBIOTICS. Give what antibiotics you can, as in Section 2.9.
INCISION. Enter the patient's abdomen through a vertical incision from her umbilicus to her symphysis pubis. Extend this down to her peritoneum, but not through it.
To reflect her peritoneum, attach a haemostat to the root of her median umbilical ligament. Pull on this to allow you to mobilize her parietal peritoneum: (1) laterally towards the walls of her pelvis, and (2) down to the anterolateral aspect of her lower segment.
CAUTION ! Be sure to mobilize her parietal peritoneum superiorly and laterally for several centimetres above the lateral extremity of her uterovesical pouch. If you don't mobilize it extensively the purse string that you are about to make will be too tight, and may leak.
To enter her peritoneum, define and divide her median umbilical ligament. Extend the incision in her peritoneum laterally and downwards on each side towards her lower uterine segment. Cut her lateral umbilical ligaments (obliterated hypogastric arteries) as you do so, and keep close to the point of firm attachment to her bladder. Reflect her bladder downwards.
Attach a curved haemostat to her uterovesical pouch in the midline, where it joins the base of her bladder. Divide her peritoneum between her bladder and her uterus, and extend your incision laterally to join the incision that you have made on entering her peritoneal cavity. Ignore the covering of peritoneum attached to the fundus of her bladder.
Attach artery forceps to the upper incised margin of her uterovesical pouch. Use this to help you mobilize a flap of peritoneum off her lower segment. Mobilize it as far as the point of attachment to the upper segment.
Sew the two layers of peritoneum that you have just mobilized with a continuous suture. Pull it tight to make a bunched-up button of peritoneal tissue. It should look watertight.
Reflect her bladder off her lower uterine segment, and proceed with a lower segment operation in the usual way (18.9).
At the end of the operation, close the incision in her uterus, and control bleeding carefully. If possible, lavage the wound with 2 g of kanamycin or tetracycline dissolved in 200 ml of warm saline. Don't attempt to remove this. If you use water only, remove it.
Insert a 26 Ch fenestrated rubber tube extraperitoneally through her abdominal wall, to lie over the suture line in her lower segment. Introduce a tube drain in her opposite iliac fossa. This will enable you to irrigate her extraperitoneal space postoperatively.
Ignore the peritoneum covering the remainder of her bladder, but stitch the remains of her median umbilical ligament to the back of her rectus abdominis muscle. As you do so, include as much of the overlying transversalis fascia as you can conveniently gather together.
Apply intermittent suction drainage through the rubber tube, and irrigate the antibiotic solution through the tube dressing drain.
If suction drainage is impractical, insert two corrugated drains, one in each iliac fossa, extraperitoneally, leave them in for 48 hours, and then shorten them 3 cm, before you finally remove them.
CAUTION ! Don't try to insert intraperitoneal drains. The aim is to try to keep her peritoneal cavity uninfected.
Fig. 18-16 MEASURING THE TRUE CONJUGATE AT CAESAREAN SECTION. If you pack a steel ruler in the the Caesar set, and measure a patient's true conjugate routinely, it will help you to decide if a trial of scar is indicated next time she goes into labour. If you do it carefully, it will give you an exact measurement, and will enable you to check the vaginal measurement you made of her her diagonal conjugate when you examined her in the antenatal clinic (it is 2 cm less).
A, her uterus has been pushed to the right and the ruler placed across her pelvic cavity. Her bladder has been displaced, partly out of the wound. In reality her symphysis is covered by the lower end of the wound and by her bladder. B, put your finger down behind her symphysis on to its posterior surface, bring your finger and the ruler out together, and see where it comes on the ruler. ''X' is her true conjugate.