First Things First

An approach to antibiotic selection for ICU patients

• Patient condition: Do not delay in gravely ill patient.
• Know the organism: But most often you will have to rely on empiric therapy.
• Antibiotics with concentration-dependent kinetics such as quinolones and aminoglycosides display increasing killing with increasing concentration above the MIC of the organism: antibiotics with time-dependent kinetics, such as beta-lactams and vancomycin, do not.
• Site of infection
• Tissue penetration:Antibiotics that are effective against a microorganism in vitro but unable to reach the site of infection are of little or no benefit to the host.
• Consider antibiotic resistance
• ICU environment
  • Know the pattern of resistance and the organisms prevalent in your ICU environment.
• Refer to antibiotic safety profile.
• Avoid overtreatment and undertreatment.
• Avoid delay: If the patient clearly needs treatment, start treatment; do not delay.
• Take specimens for culture and sensitivity before starting empiric treatment.
• Discuss your treatment with experts.
• Review the treatment once you have culture and sensitivity results.
• Consider factors in antibiotic dosing.

Adjust dose in patients with renal and hepatic insufficiency.

• Consider cost.
• Clinical correlation needed for an individual patient. Your ICU environment and other factors at your facility may suggest different treatment. These are only guidelines, not absolute recommendations.
• Clinical judgment should always guide the physician in selection, dosing, and duration of antimicrobial therapy for individual patients.
• Use of any drug should be preceded by the careful review of package insert.