Electrolyte disturbance in infants of birth weight less than 1kg in the first week of life

Abstract

Brinsmead T1,2

Electrolyte disturbance in infants of birth weight less than 1kg in the first week of life

1. Neonatal Services, Mercy Hospital for Women, Heidelberg, Vic.,Australia; 2. University of Melbourne

Aim Our project examined the proportion of extremely low birth weight (ELBW) infants in the first week of life at Mercy Hospital for Women (MHW) with Refeeding Syndrome. This condition is caused by the way infants use intravenous protein to make energy, and presents with low blood phosphate levels.

Methods For twelve months from December 2022, biochemical results relevant to Refeeding Syndrome were collected on infants of birthweight less than one kilogram, admitted to Mercy Hospital for Women nursery in the first week of life. Phosphate levels were opportunistically collected with other necessary blood tests on day 2-3 and or day 6-8 of life if biochemical results suggested Refeeding Syndrome may be present.

Results 56 infants were eligible for the audit. Data was available for 46 babies. 6 infants had blood phosphate level less than 1.6mmol/L on day 2-4 of life. 4 infants had blood phosphate level less than 1.6mmol/L on day 6-8 of life. The observed incidence of low blood phosphate in ELBW infants admitted to MHW nursery in the first week of life was 7/46 (15%). The positive predictive value of meeting criteria for screening on day 2-4 of life was 5/13 (38%). This demonstrated that Refeeding Syndrome is still occurring despite a new version of intravenous nutrition, introduced before the audit commenced, that aims to prevent the condition.

Conclusion Neonatal Refeeding is occurring in Mercy Hospital for Women’s ELBW infants in the first week of life. The screening criteria applied in this audit were useful in identifying affected infants.

Impact The MHW neonatal unit will review the evidence for phosphate therapy in infants affected by Refeeding Syndrome and set screening and treatment criteria accordingly.