Objectives To establish which medicines prescribed on Paediatric Intensive Care Units (PICU) require small dose volume preparation for administration and, the frequency of administering small doses volumes. To determine whether the potential inaccuracies of small dose volumes involved in administering these medicines are of concern to the PICU clinician.

Methods The age, weight and medicines prescribed for patients on PICU were collected for a 6 week period. The doses were converted to the volume that would be required for administration. Volumes of less than 0.2 ml were labelled as a small dose volume for the purpose of this study. Medical staff were asked whether they were aware of potential inaccuracies of small dose volumes and if this would change their clinical management of the most commonly prescribed medicines on the unit.

Results There were 269 (10.8%) prescriptions for small dose volumes (<0.2 ml), involving 44 different drugs and 1552 (7%) administered doses during the data collection period. Mean weight of the patients was 14.2 kg (±17.6) and average weight of patients receiving small dose volumes 5.04 kg (±4.08). 25% of the patients were prescribed at least one drug requiring small dose volume. Infants under 6 months received on average three small dose volume prescriptions but one in four patients were prescribed a drug which would require a small dose volume. Captopril, morphine, furosemide and ranitidine were the most common drugs administered in volumes less than 0.2 ml. Small dose volumes were more often administered via the intravenous route. One in 10 medicines stocked on the PICU require small dose volumes for patients less than 5 kg, and 1 in 30 for patient 5–20 kg. The intravenous route was involved in 8 out of 10 small dose volume medicines prescribed. Medical staff expressed concerned of potential over or under dosing occurring without awareness and would adopt changes in frequency of clinical observations for certain but not all medications.

Conclusion This small study shows that small dose volumes are used in all ages and weights of patients on the PICU but more commonly in the under 6 month patient. More data is required to identify medicines of higher risk that may require alterations in observations in the smaller patient. As a large number of medicines are involved in small dose volume measurements a medicine delivery system is required to decrease the risk of inconsistent and inaccurate doses to the paediatric patient.