Aim To audit the diluents and final concentrations used for selected neonatal continuous intravenous infusions.
Method We studied standard flow rate infusions of adrenaline, noradrenaline, dopamine, dobutamine, midazolam and morphine. The following audit standards were set:
>95% of infusions should be made to concentrations below the maximum in the local neonatal formulary (NF), where one is stated;
100% of infusions should be diluted using a compatible diluent;
>50% of infusions should be diluted in glucose (the diluent of choice).
The sample size was set as at least ten patients and a minimum of 50 infusions. Data were concurrently collected from inpatients during January 2013. Due to low patient numbers retrospective data were also collected from inpatients within the last six months. These were selected at random to minimise bias. A data collection tool was used to collect details of medicine, diluent and concentration. The NF is being updated therefore information on current practice will ensure practical administration information.
Results Ten patients and 53 infusions were audited. No adrenaline or noradrenaline infusions were prescribed. 100% of infusions were prepared using a compatible diluent.
Dobutamine: eight infusions were prescribed, seven were prepared in glucose. Concentrations ranged from 2.1–10.2 mg/mL; two infusions exceeded the 10 mg/mL maximum concentration.
Dopamine: 20 infusions were prescribed, 16 were prepared in glucose. Concentrations ranged from 1.6–10.2 mL; twelve exceeded the 8 mg/mL maximum concentration, two of which exceeded 10 mg/mL.
Midazolam: four infusions were prescribed, three were prepared in glucose. All were below 1 mg/mL.
Morphine: 21 infusions were prescribed, 16 in glucose. Concentrations ranged from 0.05–0.4 mg/mL.
Audit standard one failed: 50% (14/28) of infusions exceeded the maximum concentration where one was stated. Audit standard two passed: 100% (53/53) of infusions were prepared using a compatible diluent. Audit standard three passed: 60% (32/53) of infusions were diluted using glucose.
Conclusion Two of the three audit standards were met. Dopamine infusions were most likely to be prepared above the maximum concentration. The NF states that the maximum peripheral concentration of dopamine is 2 mg/mL but the BNFC 2012/13 states the maximum peripheral concentration is 3.2 mg/mL. 60% of infusions in this audit exceeded 3.2 mg/mL but the route they were administered was not audited. It is unknown whether infusions were administered above the maximum peripheral concentration despite being below the maximum concentration. The NF doesn't state a maximum concentration for midazolam but the draft next edition states a maximum concentration of 1 mg/mL, all infusions would have been compliant. The limitations of this audit included time constraints preventing more data being collected (e.g. patient weight, route of administration, fluid restriction, reason for choice of diluent and/or concentrated solution), the small sample size may have skewed the results, and only a proportion of prescribers and administration practices were captured.
Recommendations Halve the standard infusion rate of dopamine, no infusions would then have been over 8 mg/mL; survey nursing staff to assess their understanding of maximum concentrations to provide targeted training; re-audit once changes have been made, ideally over a longer time period using a larger sample.