Microbiological surveillance and parenteral antibiotic use in a critical care unit.

OBJECTIVE: To evaluate parenteral antibiotic utilization and bacterial resistance patterns in a critical care unit (CrCU). DESIGN: Descriptive, prospective audit of infection site, culture and antimicrobial susceptibility test results, parenteral antibiotic usage and duration, total antibiotic acquisition costs, and length of stay. SETTING: A 17-bed medical-surgical CrCU in a tertiary care teaching hospital in Metropolitan Toronto. PATIENTS: Two hundred and fifty-eight patients admitted to the CrCU between May 1995 and April 1996 who received antimicrobial therapy. RESULTS: The most frequently prescribed antibiotics were cefazolin (47%, 1098 g), gentamicin (33%,141 g) and ceftriaxone (20%, 255 g). The most common indications for antimicrobial therapy included surgical prophylaxis (34%) and pneumonia (35%). The following organisms were isolated from patients treated with antibiotics: Staphylococcus aureus (26%), Pseudomonas aeruginosa (13%), enterococci (12%), Haemophilus influenzae (11%), Escherichia coli (11%), Enterobacter cloacae (8%) and other Gram-negative bacilli (19%). Only 9% of Gram-negative bacilli were resistant to aminoglycosides, 3% were resistant to ciprofloxacin and no extended-spectrum beta-lactamases or imipenem-resistance were detected. No vancomycin-resistant enterococci and only two methicillin-resistant Staphylococcus aureus isolates were identified. CONCLUSIONS: Antibiotic use during the audit appeared appropriate for the specific clinical indications. Low levels of bacterial resistance were detected during the audit.

Pharmacist's management of drug-related problems: a tool for teaching and providing pharmaceutical care.

During the development of education and practice models based on the philosophy of pharmaceutical care (PC), six pharmacists worked with the University of Toronto Faculty of Pharmacy to implement the PC model in their practice sites. These pharmacists found it necessary to modify existing tools to create one that explicitly guided them through the PC process, including the phase of monitoring patients for desired outcomes. This resulted in the development of the Pharmacist's Management of Drug Related Problems. This tool requires pharmacists to collect patient drug and medical data and write responses to specific questions about the data to interpret their significance. As proficiency in providing PC is attained, the questions and space for written responses can be eliminated, leaving a comprehensive documentation system of patient outcomes and the data collected, recommendations made, and monitoring completed by the pharmacist. This tool has been adopted by the University of Toronto Faculty of Pharmacy and is being used in various continuing education programs and by practicing pharmacists across Canada.

Lack of pharmacokinetic and pharmacodynamic interactions between ketoconazole and prednisolone.

The effects of ketoconazole on the pharmacokinetics and pharmacodynamics of intravenous prednisolone (14.8 mg) were assessed in six healthy volunteers. Subjects were studied with and without receiving ketoconazole, 200 mg orally for 6 days. The addition of ketoconazole did not significantly change the clearance (96 +/- 11 versus 90 +/- 11 ml/hr/kg), mean residence time (4.29 +/- 0.43 versus 4.45 +/- 0.59 hours), volume of distribution (0.41 +/- 0.02 versus 0.40 +/- 0.02 L/kg), or plasma protein binding characteristics of prednisolone. The suppressive effects of prednisolone on serum cortisol, blood basophil, and helper T lymphocyte values, assessed by the ratio of the area under the curve (AUC) after prednisolone administration to the baseline AUC, was not altered significantly by ketoconazole. The 50% inhibitory concentration values derived from pharmacodynamic models developed to describe the direct suppressive effects of corticosteroids indicated no alteration in intrinsic sensitivity in the presence of ketoconazole. Ketoconazole does not appear to alter the pharmacokinetics or the pharmacodynamic response patterns of selected direct suppression effects of single low doses of prednisolone.