Inhaled agents and propofol are used to sedate patients for surgical interventions. Economic analysis of theses agents is complex and include acquisition cost, wastage, adjuvants, flow rate of fresh gas, equipments, and patient-specific factors. OBJECTIVES: The study purpose was to benchmark annual costs of halothane, isoflurane, desflurane, sevoflurance, enflurane, thiopenthal and propofol in canadian pediatric institutions. METHODS: A written survey was sent to 9 major hospital pharmacy department in 1999 with 2 recalls regarding 1997-98 and 1998-99 fiscal year. RESULTS: Response rate was 78% (7/9). Our cohort includes a total 1005 beds, 48659 admissions/year and 64552 surgical procedures/year. Day surgery represents 31% of total cases. Inhaled agents and propofol represented 47,4% (n=7, sd=8,1) of total drug costs in operating room (OR) and recovery room (RR). Anesthetic agents costs were on average 0,18 $CDN/min of surgery (n=4, sd=0,05) in 1997-98 and 0,21 $CDN/min (n=3, sd=0,13) in 1998-99. Total costs/patient of all drugs used were 30,26 $CDN (n=4, sd=8,8) in 1997-98 and 26,11 $CDN (n=4, sd=6,28) in 1998-99. Total costs/patient for anesthetic agents were 13,54 $CDN (n=4, sd=2,7) in 1997-98 and 12,48 $ CDN (n=4, sd=1,98) in 1998-99. Costs reduction seems to be mainly caused by price reduction of isoflurane for 1998-99 which went from 1st position in 1997-98 (171 610 $CDN, n=5) to 3rd position in 1998-99 (116 700 $CDN, n=5) even with a 10% increase in consumption. Total costs of these agents increased by 3.5%. Sevoflurane has taken the 1st position in 1998-99. CONCLUSION: There are little data available in the literature to allow benchmarking in the pediatric OR. Further studies are required to identify the best ratio useful to monitor such costs as well as relevant outcomes.