Chapter 15. Paediatric surgery

Table of Contents
Surgery in children
Intestinal obstruction in the first few days of life
Operating for a neonatal acute abdomen
Hypertrophic pyloric stenosis
Disorders of the omphalo-mesenteric duct (Meckel's diverticulum)
Anorectal malformations
Hirschsprung's disease
Congenital abnormalities of the female genital tract
Omphalocele (exomphalos)
The surgery of neonatal jaundice
Spina bifida, meningocele, and myelomeningocele
Congenital vascular lesions
Other paediatric problems

Surgery in children

There are two periods in paediatric surgery: (1) The surgery of the neonatal period, which is mostly concerned with those congenital malformations which need urgent treatment at birth. The few you can treat are described here, but you may feel that most of them are too difficult, and unrewarding, to come high in your list of priorities. (2) The surgery of the rest of childhood, most of which is more conveniently described in other chapters, particularly in those in Volume Two on trauma, which describes children's fractures (69.6) and burns (Chapter 58). Other important aspects of paediatric surgery are most kinds of sepsis, particularly abscesses (5.2), pyomyositis (7.1), and osteomyelitis (7.2); intestinal obstruction by Ascariasis (10.6) and intussusception (10.8); inguinal hernias (14.5), the urological problems of childhood (Chapter 23), poliomyelitis (Chapter 27), talipes (27.15), Burkitt's lymphoma (32.3) and other childhood tumours. Such surgical paediatric problems as do not more conveniently fit anywhere else are here. Many of them will probably have a low priority. If possible refer them.

The fluid requirements of children are described in Chapter 15 of Primary Anaesthesia and their anaesthetic requirements in Chapter 18. Very young children tolerate fluid and electrolyte loss badly: they don't have the normal postoperative sodium and water retention of adults, they cannot pass a concentrated urine, and they easily become dehydrated and hypoglycaemic.

PAEDIATRIC SURGERY ANAESTHESIA. See A 18.1.

If you want to use local anaesthesia on a neonate, sedate him with 1 mg of diazepam: (1) You can dilute 1 ml of 2% lignocaine to 20 ml, and use this as the maximum dose. (2) You can infiltrate the line of the incision with 0.5% procaine, or 0.25% lignocaine. The maximum dose is about 5 ml[md]see Fig. A 5- 1. Avoid adrenalin in the neonate.

General anaesthesia is better if your anaesthetist is good. Use Ayer's T-piece, awake intubation (A 13.6), followed by general anaesthesia and intramuscular suxamethonium, as in A 18.2.

If a neonate requires an urgent operation, operate at 24 hours, or as soon afterwards as possible. Lung function is poor if you operate before 24 hours, when his lungs are not yet fully expanded. Weigh him and put up a drip. Give him vitamin K(,1) 1 mg, and start him on ampicillin 100 mg/kg/24 hours in 3 divided doses.

Make sure the theatre is warm. Place him on a well-padded cross made of two splints, and bandage his arms and legs to it. Cover the rest of his body except for his abdomen with cotton wool. Monitor and replace his blood loss with the greatest care (3-1). If HIV is common in your area, try to use blood from his father or mother. Weigh all blood-soaked swabs accurately, on a scale borrowed from the pharmacy if necessary. Replace blood ml for ml if more than 5 ml are lost. During the operation he will probably need 5 to 10 ml/kg/hour of 5% dextrose in Ringer's lactate.

INTRAVENOUS LINES. An infant requiring general anaesthesia should have a scalp vein drip, a cut-down (A 15.2), or a central venous line (A 19.2).

FLUIDS AND ELECTROLYTES. Replace all a child's initial fluid deficit (A 15.3) during the 3 to 6 hours that you are starving him, before you start to operate. Prescribe his postoperative fluids yourself, as in Figure A 15-4. Don't leave this to the nurses, and don't exceed 100 ml/kg in 24 hours.

For major surgery, where possible, pass an indwelling catheter. This is not appropriate under the age of 3 years; so, for a boy, use about 50 cm of plastic Paul's tube of suitable size; strap a plastic bag around the perineum of a girl. A child should pass 1ml/kg/hour, or:

0 to 1 year, 10 to 20 ml an hour.

1 to 4 years, 20 to 24 ml an hour.

4 to 7 years, 24 to 28 ml an hour.

7 to 10 years, 28 to 30 ml an hour.

10 to 12 years, 30 to 35 ml an hour.

More than 12 years, 50 ml an hour.

POTASSIUM. If a child is not taking oral fluids by 24 hours, he needs a potassium supplement. Add 10 mmol to 500 ml of intravenous fluid (20 mmol/litre). Don't give him more than 10 mmol/hour or 3 mmol/kg/day. Or, use half-strength Darrow's solution, which contains 18 mmol/litre. Potassium replacement can be very dangerous in children, if it is handled incorrectly.

If he becomes drowsy postoperatively, and his gut becomes silent, suspect ileus, and give him potassium.

NUTRITION. Interrupt feeding as little as you can. Don't starve a child for more than 4 hours before the operation, and get him feeding again as soon afterwards as you can. Listen every 6 hours for the return of bowel sounds, and note whether he has passed faeces or flatus; these signs show that feeding can start. Bowel sounds alone are not so reliable in children, so some surgeons adjust the time of feeding to the nature of the operation, and decide if it is safe to feed a child by aspirating his stomach hourly, before each intake of feed.

Where possible, give him the fluid he needs as half-strength Darrow's solution in 5% dextrose (A 15-6). If he was not starved for more than 4 hours, and feeds are restarted soon, he is not going to be short of energy.

If you are able to give him 50% glucose through a central venous line (unlikely), use it to replace his energy deficit resulting from starvation. Reckon that, if he cannot feed orally for more than 3 days, he needs 1 to 2 g/kg/day. Test his urine and watch for glycosuria and an osmotic diuresis.

Alternatively, dilute 25 ml of 50% dextrose in 500 ml of half-strength Darrow's solution and increase the concentration gradually.

In working out the energy content of various fluids, use Figure 15-6 in Primary Anaesthesia, or remember that a litre of 10% dextrose contains 1700 kJ (400 cal). A child's daily postoperative energy needs are[md]

A newborn child needs 190 to 210 kJ/kg (45 to 50 cal/kg).

From 3 to 10 kg he needs 250 to 335 kJ/kg (60 to 80 cal/kg).

From 10 to 15 kg he needs 190 to 270 kJ/kg (45 to 65 cal/kg).

From 25 to 35 kg he needs 145 to 190 kJ/kg (35 to 45 cal/kg).

From 35 to 60 kg he needs 125 to 145 kJ/kg (30 to 35 cal/kg).

CAUTION ! If he becomes drowsy, or unconscious,, or behaves strangely, suspect hypoglycaemia, or less commonly, water intoxication from lack of electrolytes relative to water.

If you are operating proximal to the upper jejunum, a jejunostomy at the time of the operation is a good way to feed him. See also 28.3.

Fig. 28-1 A CHILDREN'S SURGICAL WARD as sketched by a student during her elective term in Africa. There are so many sick children that cots have to be shared. Mothers have been admitted so that they can breast-feed and comfort their children. Kindly contributed by Celly Bacon.