Hypocalcaemia in a paediatric intensive care unit.

Data on the incidence of hypocalcaemia in critically ill children admitted to a Paediatric Intensive Care Unit (PICU) is scarce, especially from developing countries. We have studied serum calcium in a prospective cohort of 100 children (68 boys, 32 girls), admitted consecutively to a PICU of a tertiary-care teaching hospital and correlated it with the outcome. Venous blood was obtained for serum calcium, magnesium, sodium, potassium, and arterial blood for ionized calcium and pH at admission and on every alternate day of hospital stay. Hypocalcaemia was present in 35 per cent of patients at admission and occurred in another 13 per cent during hospital stay. The incidence of hypocalcaemia (serum total calcium < 8.5 mg/dl) was 22.4, and ionized hypocalcaemia (serum ionized calcium < 3.2 mg/dl) was 32.4 episodes/100 patient days. Correlation between serum total and ionized calcium levels was not significant (r = 0.25, p = 0.089). Mortality was significantly higher in hypocalcaemic (28.3 per cent) compared with normocalcaemic (7.5 per cent) patients (p < 0.05). We conclude that hypocalcaemia is common in critically ill children admitted to a PICU and is associated with higher mortality.