Drug utilisation in adult, paediatric and neonatal intensive care units, with an emphasis on systemic antimicrobials

Introduction
Critically ill adults, children and neonates receive drugs that are often administered parenterally and in infusions. Considering patient illness severity, empirical broad-spectrum antimicrobials are commonly used. We conducted the present study to evaluate the drug use in this population, with a special focus on antimicrobials.

Material and methods
A prospective cross-sectional study was implemented in adult, paediatric and neonatal intensive care units. Various prescribing and supplemental indicators were used for drug comparisons. The World Health Organisation’s list of essential drugs, the national drug formulary and critically important antimicrobial drugs were assessed. Proportions and median (range) were used to represent categorical and numerical values.

Results
Four hundred and ninety-six critically ill patients were enrolled in the study, with 5,636 prescribed drugs used for 31,993 patient-days. Critically ill adults received significantly more drugs compared to children and the neonatal population (11 [8–16], 9 [6–17] and 5 [3–12] respectively). Critically ill neonates received significantly fewer of the drugs listed in the national formulary compared to older children and adults (94.1% [10.1], 92.4% [32.4] and 80.1% [20.4]). Critically ill neonates received fewer antimicrobials (82% compared to 91.3% in adults and 98% in children). Furthermore, critically ill adults received more broad-spectrum antimicrobials compared to neonates. Prolonged empirical antimicrobial use was observed more in critically ill children (52%) compared to adults (29.8%). A large majority of the antimicrobials were critically important for 87.7%, 83.9% and 86.5% of patients in the adult, paediatric and neonatal intensive care units.

Conclusions
We observed significant differences in terms of drug classes predominantly used in various age groups of critically ill patients, particularly regarding the nature and type of antimicrobial drugs and the duration of antimicrobial therapy.