ZELENITSKY SA, ARIANO RE, SILVERMAN R, HARDING GK; Interscience Conference on Antimicrobial Agents and Chemotherapy.

Abstr Intersci Conf Antimicrob Agents Chemother Intersci Conf Antimicrob Agents Chemother. 2000 Sep 17-20; 40: 30.

Univ. of Manitoba, Winnipeg, MB, Canada

BACKGROUND: Antibiotic pharmacodynamic principles are used to individualize regimens and optimize therapy. Our goal was to conduct, to our knowledge, the first pharmacodynamic study in surgical prophylaxis.METHODS: Data from a prospective study of 146 patients who underwent elective colorectal surgery were evaluated. Patients received high dose gentamicin (4.5 mg/kg) pre-operatively or standard dose gentamicin (1.5 mg/kg) pre-operatively and for 24 h post-operatively both in combination with metronidazole. A reference group (n=16) was used to characterize gentamicin pharmacokinetics, and a validation group (n=19) was used to test the equations predictive performances. Risk factor analyses were conducted to examine relationships between gentamicin concentrations and surgical site infections (SSI). Receiving Operator Curves were used to identify concentration breakpoints.RESULTS: No risk factors for infection were identified in the high dose group (n=68). Diabetes, surgery duration, gentamicin concentration at incision (CI), concentration at closure (CC), timing of pre-operative dose and stoma were risk factors in the standard dose group (n=65). In the multivariate analysis, CC (p=0.0008) and age (p=0.03) were independent risk factors. Critical breakpoints of 5.19 microg/ml for CI (p=0.002) and 1.62 microg/ml for CC (p=0.002) were identified. CI above or below 5.2 microg/mL had infection rates of 21.2% and 53.1% (p=0.008), and CC above or below 1.62 microg/mL had SSI rates of 20.6% and 54.8% (p=0.004).CONCLUSIONS: Our study shows the importance of antibiotic pharmacodynamics in surgical prophyalxis. It demonstrates strong correlations between gentamicin concentrations and outcome and suggests that optimal concentrations can reduce or negate other risk factors for infection.KEYWORDS: Gentamicin; Pharmacodynamics; Surgical

Publication Types:

• Meeting Abstracts

Keywords:

• Anti-Bacterial Agents
• Antibiotic Prophylaxis
• Communicable Diseases
• Cross Infection
• Double-Blind Method
• Gentamicins
• Humans
• Infection
• Infection Control
• Metronidazole
• Prospective Studies
• Research
• Risk Factors
• Surgical Procedures, Elective
• Surgical Wound Infection
• Wound Infection
• analysis
• drug therapy
• pharmacokinetics
• prevention & control
• surgery
• therapy

Other ID:

• GWAIDS0010976

UI: 102248474

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