Presented at the Neonatal Society 2016 Autumn Meeting.
Harper Gow J, White H, Jain A
Gloucester Royal Hospital, Gloucester, UK
Background: Weight loss and hypernatraemia in premature infants born at 26-32 weeks gestation was frequent despite administration of the usual fluid regime. This was attributed to an inadequate volume of TPN prescribed per kilo per day. It was hypothesised that increasing the volume given would reduce weight loss in the first week of life and reduce hypernatraemia.
Methods: A change was made in the TPN prescription from day 1 = 60ml/kg/day, day 2 = 90ml/kg/day, day 3 = 120ml/kg/day, Day 4= 150ml/kg/day (Cohort 1) to day 1 = 75ml/kg/day, day 2= 100ml/kg/day, day 3= 120ml/kg/day, day 4= 150ml/kg/day (Cohort 2). Sodium concentration in TPN remained unchanged. Sodium in standard TPN was as follows; Day 1 and 2 = 0mmol/kg/day, Day 3 =2.35mmol/kg/day, day 4 = 2.96mmol/kg/day and from day 5 = 2.91mmol/kg/day. Case notes were used to record fluid prescription, serum sodium and weight loss in the first week of life. Data collected from each cohort was compared.
Results: Cohort 1 n= 38, Cohort 2 n=52. The prevalence of weight loss >12% was similar in the two cohorts (31.6% vs 30.7%). Weight loss of >12% fell from 45.5% to 40.0% in babies <30 weeks. Weight gain >12% rose from 0% in Cohort 1 to 7.6% in Cohort 2. Hypernatraemia (Sodium >145mmol/L) fell overall from 50% (Cohort 1) to 30% (Cohort 2). In babies born <30weeks gestation hypernatraemia fell from 63.6% (Cohort 1) to 29.6% (Cohort 2) and in babies over 30 weeks gestation from 44.4% (Cohort 1) to 32% (Cohort 2). Hyponatraemia (Sodium <133mmol/l) increased from 7.9% (Cohort 1) to 26.9% (Cohort 2). In Cohort 2, 37% of babies <30 weeks had hyponatraemia compared to 16% in babies >30weeks. There was no correlation between hyponatraemia and weight gain.
Conclusion: Adjusting fluid volumes prescribed reduced both extreme weight loss and hypernatraemia. It had the greatest effect on weight loss and hypernatraemia in babies <30 weeks gestation. Sodium and water depletion appeared more prevalent in babies under 30 weeks gestation. Earlier addition of sodium in this group might be necessary.
Corresponding author: firstname.lastname@example.org
Farnaroff and Martin’s Neonatal Perinatal Medicine Katherine Macrae Dell
Moyses HE, Johnson MJ, Leaf AA, Cornelius VR, Am J Clin Nutr. 2013 Apr;97(4):816-26. Epub 2013 Feb 27