Technical response to the Neonatal and Paediatric Pharmacist Group's proposal to standardise intravenous infusion concentrations for children in the UK

Examining safety and efficacy of a fixed concentration heparin dosing strategy for anticoagulation in neonatal extracorporeal membrane oxygenation

OBJECTIVES

The paediatric intensive care unit changed heparin infusion dosing from a variable weight-based concentration to a fixed concentration strategy, when smart pump-based drug library was introduced. This change meant significantly lower rates of infusion were needed for the same dose of heparin in the neonatal population. We performed a safety and efficacy assessment of this change.

METHODS

We performed a retrospective single-centre evaluation based on data from respiratory VA-extracorporeal membrane oxygenation (ECMO) patients weighing ≤5 kg, pre and post the change to fixed strength heparin infusion. Efficacy was analysed by distribution of activated clotting times (ACT) and heparin dose requirements between the groups. Safety was analysed using thrombotic and haemorrhagic event rates. Continuous variables were reported as median, interquartile ranges, and non-parametric tests were used. Generalised estimating equations (GEE) were used to analyse associations of heparin dosing strategy with ACT and heparin dose requirements in the first 24 h of ECMO. Incidence rate ratios of circuit related thrombotic and haemorrhagic events between groups were analysed using Poisson regression with offset for run hours.

RESULTS

33 infants (20 variable weight-based, 13 fixed concentration) were analysed. Distribution of ACT ranges and heparin dose requirements were similar between the two groups during the ECMO run and this was confirmed by GEE. Incidence rate ratios of thrombotic (fixed v weight-based) (1.9 [0.5-8], p = .37), and haemorrhagic events (0.9 [0.1-4.9], p = .95) did not show statistically significant differences.

CONCLUSIONS

Fixed concentration dosing of heparin was at least equally effective and safe compared to a weight-based dosing.