A survey of antibiotic prescribing practices in Australian and New Zealand intensive care units.

OBJECTIVE

To evaluate antibiotic prescribing practices in empirical and directed treatment of severe sepsis and septic shock in Australian and New Zealand intensive care units.

DESIGN, SETTING AND PARTICIPANTS: Case vignette survey of intended antibiotic prescribing for ICU patients with sepsis associated with community-acquired pneumonia (CAP), intra-abdominal infection (IAI), hospital-acquired pneumonia (HAP) or an unidentified infectious cause (UIC). Eighty-four specialists and advanced trainees working in an ICU setting in Australia and New Zealand responded to a questionnaire survey conducted between February and May 2009.

MAIN OUTCOME MEASURES

Empirical and directed antibiotic therapy, including mode of administration, frequency of administration, dose and duration of therapy.

RESULTS

A total of 656 antibiotics were empirically "prescribed", including 25 unique antibiotics. Combination therapy was prescribed in 82% of cases, with dual cover for CAP and triple therapy for IAI most common. Directed single-agent cover for Pseudomonas aeruginosa in HAP and flucloxacillin monotherapy for methicillin-sensitive Staphylococcus aureus bacteraemia were prescribed in 65% and 51% of cases, respectively. Supportive gentamicin therapy was commonly recommended (32% of all cases), predominantly in the form of once-daily dosing. Daily gentamicin dosage varied from 3 to 7mg/kg (excluding one outlier), and was largely compliant with recommendations (76% of doses being ≥5 mg/kg). Main areas of noncompliance with guidelines were provision of broader cover for resistant organisms and Β-lactam underdosing. Continuous and extended infusions were uncommon (5%).

CONCLUSIONS

Antibiotic prescribing was largely appropriate, but consideration of site-specific resistance profiles and avoidance of low dosing is advocated to provide appropriate upfront cover, prevent underdosing and reduce the risk of developing resistant organisms.