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294 Congenital Diaphragmatic Hernia and Diaphragmatic Eventration

off inotropes and pulmonary vasodilators if they were required. In should be anticipated with cross-matched blood. Trauma to the intes-
those patients who have little cardiorespiratory compromise, a period tines, leading to perforation and peritonitis, is also possible.
of 24 hours (the so-called “honeymoon period” in CDH) to allow any Postoperative pleural effusion is expected in the immediate
instability to announce itself is prudent. Although there may be no postoperative period. Persistence of this can impair lung expansion and
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long-term advantage of early versus delayed surgery, a somewhat weaning off the ventilator. This complication is increased if a hernia sac
delayed approach (24 to 48 hours) may allow patients with significant is not identified and left in situ. The sac then will act as a compartment
cardiopulmonary disease, who would not survive despite any operative for fluid to accumulate. Intraoperative excision of the hernia sac, if
intervention, to be selected. In an otherwise stable patient, however, any present, is therefore the best prevention. Management usually consists
long delay can be detrimental. 8 of inactivity to allow the fluid to resorb. In those cases where this
The infant is taken to the operating theatre, and antibiotics, if not is delayed, thus causing respiratory symptoms or delayed recovery,
already administered, are given at induction. The operative steps are drainage via a chest drain may be required; this is seldom necessary.
summarised as follows: Mediastinal shifts can occur in the postoperative period, as pressure
1. A transverse supra-umbilical incision is made. and volume changes due to reducing the abdominal contents ensue. The
mediastinal shift induced by CDH does not usually shift back to the
2. Rarely, for large right-sided lesions with a larger proportion of the central position immediately, but does so slowly. The space is initially
liver in the chest, a thoracoabdominal incision is required.
filled by air (Figure 45.6) and later on by fluid.
3. The intestines or viscera are inspected and gently and gradually Misinterpretation of the postoperative changes can lead to
reduced from the chest. Often, on the left, the spleen is particularly unnecessary insertion of a chest drain. This can cause large changes in
difficult to reduce without causing injury, and a finger or retractor volumes and pressures, with consequential changes in lung expansion,
introduced into the chest can be use to guide it into the abdomen. resulting in a true pneumothorax (especially in the contralateral lung,
Rarely, the defect in the diaphragm needs to be enlarged to facilitate which will then require drainage).
this. In right-sided lesions, reduction of the liver can be associated An incisional hernia can occur in patients with tight abdominal
with altered venous return to the heart due to reconfiguration of the wall closure and those with patch closure of the abdominal wall.
inferior vena cava; this should be anticipated and communicated to the Semielective or elective repair after a period of stabilisation and growth
anaesthetist. is advisable.
4. After reduction of the abdominal contents, the chest is examined Recurrence is seen in 5–15% of patients. 9,10 The incidence of
for a hernia sac. This is best done by grasping and incising over a recurrence is higher in patients in whom a patch repair is needed (up to
lower rib to free a sac if present. The entire sac should be excised. The 50%) and in those in whom the closure is under tension. The incidence
hypoplastic lung can then usually be seen in the chest. of recurrence is reported to be lower in patch repair using biological-
5. The defect in the diaphragm is inspected, and the decision for based material (e.g., Permacol); 11,12 however, this is not a universal
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primary or reinforced closure is assessed. Mobilisation of the leafs of finding. Management of recurrence is surgical, with principles
muscle, in particular on the posterio-lateral aspect, can increase the similar to those for primary surgery. With large defects and those with
amount of muscle available. multiple recurrences, the need for muscle-based (e.g., abdominal wall
or latissimus dorsi) flaps 14,15 should be considered.
6. Primary closure is then achieved with interrupted nonabsorbable Gastro-oesophageal reflux is seen in 50–90% of patients, and should
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sutures. With large defects, sutures can be placed individually and tied at be treated as in any other patient. Overall, however, the requirement for
the end. Sutures may need to be placed around lower ribs in large defects.
surgical fundoplication is higher than in normal children.
7. If the defect is too large for primary closure, a prosthetic patch Poor feeding and growth are also seen in some (sometimes needing
of artificial or natural graft material is fashioned in the size and gastrostomy placement).
shape of the defect, allowing for a small amount of curvature. The Intestinal obstruction caused by adhesions can occur, and initially
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choice of material will depend on local availability, but can include is treated conservatively or operatively, depending on clinical status.
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polypropylene, Dacron , Gore-Tex (polytetrafluoroethylene), Chest wall deformities can occur in the forms of pectus carinatum
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Surgisis , and Permacol . The patch is sutured in place with (approximately 30%) and scoliosis (20%). The incidence is higher in
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nonabsorbable sutures in a manner similar to that described above; those patients with a large defect requiring a tight closure, or those
again, the lower ribs may need to be used to anchor the stitches. A
chest drain is not mandatory, but is used by some judiciously.
8. If artificial material is not available, a muscular graft (e.g., abdominal
wall or a lattissimus dorsi graft) is created to close the defect.
9. Abnormalities of rotation can be associated with CDH, and if a
narrow midgut mesentery is present, a Ladd’s procedure is performed.
10. Abdominal wall closure can be difficult due to the increased
tension caused by return of the intestines into the abdomen.
Occasionally, to avoid a tight abdominal wall closure with the
consequences of respiratory compromise and abdominal compartment
syndrome, the abdomen may need to be closed with a patch.
11. A postoperative chest x-ray is performed to check the position of
the diaphragm.
Laparoscopic and thoracoscopic approaches for CDH repair have
been described by some centres in select cases. These approaches are
suitable for specialised personnel in experienced centres, as they can
impose further physiological stresses on the infant.
Figure 45.6: Early postoperative chest x-ray in same patient as in Figure 45.2.
Postoperative Complications The lower right chest cavity is filled with air and a small amount of fluid. There is
Bleeding due to trauma to liver or spleen can occur intraoperatively and still some mediastinal shift.