Hypoglycaemia is one of the metabolic abnormalities in infancy and childhood. It can be transient or persistent. The most common cause of persistent hypoglycaemia in the first year of life is hyperinsulinaemia with an incidence of 1 case per 250 000 patient-years. Hypoglycaemia is often severe and intractable.

The anaesthesia management of a 22 day old neonate is described below.

A 22 day old neonate was transferred from one tertiary hospital to our hospital in view of convulsions. He was a full term, born of caesarean section due to non progress of labour, born to non diabetic mother of non consanguineous marriage.

On day1 of life the child convulsed twice with a tonic clonic convulsion, was diagnosed to have hypoglycaemia, though there was no dysmorphism and hepatomegaly. On admission to the tertiary hospital the blood sugar was 26 mg%, which required intravenous glucose to maintain blood sugars and would develop low blood sugar on decreasing the drip rate

The insulin to glucose ratio was >1 while the serum ammonia level was normal.

He developed repeated episode of convulsion for which he was transferred to our hospital

He was continued on glucose drip and started on fortified feeds. The patient had a GDR of 18 mg/kg/min.

He maintained on fortified feeds of ¾th calorie requirement and also on diazoxide 12 mg/kg/day, he was subsequently normal till the 10th day where in he developed a repeat episode of convulsion for which he was then started on octreotide 6 and then 8 µg subcutaneously 3 times a day and subsequently increased to 4 times a day. Hydrochlorothiazide was also added. The EEG showed low amplitude, though the USG and CT scan revealed no abnormality, the child was posted for a sub total pancreatomy as he had repeated episodes of hypoglycaemia despite the medical line of management.

He was discontinued on feeds 6 hours prior to surgery while the iv infusion of dextrose was continued. The blood sugar levels were checked every 15 minutes with haemoglucochecks and maintained between 160-200 mg/dl. The blood gases and electrolytes were with in normal range

Anaesthesia was induced with thiopentone sodium 5 mg/kg and atracurium 1mg/kg. Trachea was intubated with 3.5 mm tube. Maintenance was with Oxygen in nitrous oxide and isoflurane (0.5%-2%) with intermittent doses of atracurium. An 18G epidural catheter was introduced by an 18G Touhy needle at L3-L4 space and passed up toT6. Bupivacaine 0.125% 4 ml was topped up every 90 mins after an initial bolus of 4 ml of 0.25%.

The internal jugular vein was cannulated with 20G cannula for monitoring CVP and the left radial artery was cannulated with a 24G cannula, kept patent with heparinized saline, this was used for the invasive blood pressure monitoring as well as for the blood sugar estimation. A 20 G cannula was also inserted in to the left saphenous vein which was used for dextrose administration. The monitoring used was NIBP, pulse oximetry, ECG, capnography and temperature.

An infusion of ¼th normal saline with dextrose was kept as maintenance fluid and ringer lactate 10 ml/kg was used as replacement fluid. The blood loss incurred was 150 ml and was replaced by the equal amount of packed cells. The blood sugar was estimated every 15 mins and labarotory reports were done every 30 mins. It was maintained in between 160-200 mg/dl.
At the end of surgery the patient was reversed with neostigmine 0.05 mg/kg and glycopyrolate 0.04 mg/kg and the trachea extubated.

The surgery lasted for 5 hours and post operatively analgesia was provided by the epidural catheter with a bupivacaine 0.125% 4 ml for the next 72 hours and subsequently with diclofenac suppository.

Postoperatively the blood sugars were maintained in the range of 200-400 mg% for which insulin was continued, 6 hours later there was a dip in the glucose to about 35 mg% necessitating glucose infusion, and the cessation of insulin, this persisted for 6-7 days following which the glucose levels stabilized.

Patient was discharged on day 45 on breast feed 45 ml feed 2 hourly + 10 ml 10% dextrose + 35 ml lactogen + 2 tsp cornstarch. The patient developed intestinal obstruction at day 55 of age, single loop adherent at previous drain site, recovery uneventful. At present 16 months of age on full diet off drugs, had 2 episodes of convulsions with sweating and up rolling of eyeballs following vomiting, these required injection glucagon. EEG was done at 13 months of age and was normal. At 1 year of age using Infant Bayley scale and Vineland Social Maturity scale, mental age was 1 yr, motor age 9 months, DQ 91 average, Social age 1year, SQ 100 average.

The hallmark of hyperinsulinism in the infant and child is inability to withstand fasting because hyperinsulinaemia prevents the mobilization of endogenous glucose via glycogenolysis, thereby favouring the development of hypoglycaemia.1
In response, there is increased demand for feeding, ravenous appetite and weight gain. Jitteriness and seizures1,2 are the most common presentation, especially with functioning islet cell adenomas, whose hall mark is episodic and unpredictable insulin release resulting in rapid development of hypoglycaemia and its neurologic complication.
The sine qua non for the diagnosis of hyperinsulinism3 remains an inappropriately elevated insulin concentration at the time of documented hypoglycaemia, i.e. an insulin concentration of more than 10 µg/ml at a time when the plasma glucose concentration is less than 40 mg/dl.
The pathology of hyperinsulinism has been classified into disorders called nesidioblastosis, ß-cell hyperplasia and when confined to a discreet area ß- cell adenoma or adenomatosis.
Medical management4 consists of the infusion of glucose, the use of drugs to control insulin secretion and frequent carbohydrate rich feedings, including corn starch. The management of persistent neonatal or infantile hypoglycaemia includes increasing the rate of intravenous glucose infusion to 8 -15 mg/kg/min. Surgical exploration should be undertaken in severely affected neonates who are unresponsive to drugs (diazoxide, longstanding somatostatin). In such instances, near total resection of 85%-90% of the pancreas is recommended. When the diagnosis is established before 3 months of life, surgery is usually needed.

The diagnostic features are

Oral diazoxide 10-25 mg/kg/24 hr given every 6 hrs may reverse hyperinsulinaemic hypoglycaemia but also causes hirsutism, oedema, nausea, hypeuricaemia, electrolyte disturbances, advanced bone age, IgG deficiency and rarely hypertension with prolonged use.

Octreotide is administered subcutaneously every 6 to 12 hours in doses 20-50 µg in neonates and young infants. Potential but unusual complications include poor growth due to inhibition of growth hormone release, pain at the injection site, vomiting, diarrhoea and hepatic dysfunction.

Management of neonatal hypoglycaemia5:

In normal infant the glucose requirement6 is 4-6 mg/kg/min and the fluid requirement is 4-6 ml/kg/hr or 100-150 ml/kg/day. To balance both these requirements, a 5-10% dextrose solution is the maintenance fluid for neonates in the ward. In hyperinsulinaemia, the glucose requirement increases to 10 mg/kg/min. These hyperinsulinaemic patients utilize glucose for anabolic activities, hence their kidneys are not presented with a high glucose load causing diuresis. The quantum of glucose presented to the kidney is determined by the concentration of the glucose solution, rate of infusion, blood volume and the consumption of glucose en route to the kidney. Of primary importance in the anaesthetic management7 of insulinomas is the maintenance of adequate levels of blood sugar in the dynamic intraoperative period with labile fluctuations of blood sugar and the fluid shifts of major surgery. Secondarily these blood sugar levels are used as a marker of tumour removal. In paediatrics it is not possible to keep the patient awake to warn the symptoms of hypoglycaemia. Thus we preferred to maintain moderate levels of hyperglycaemia and regularly check the blood levels at 15 min intervals to avoid hypoglycaemia (blood sugar > 60 mg%). Combination of general anaesthesia and epidural anaesthesia reduced the requirement for general anaesthesia and provided adequate analgesia. We conclude that surgery is a semi emergency to protect the nervous system from the repeated attempts of hypoglycaemia and hypoxia due to convulsions. The quality of life will depend on the integrity of the CNS. The fluid management and the blood sugar levels are labile and require perfect coordination and team work between the paediatric endocrinologist, anaesthetist, surgeon and neurologist.