Case Study – COLISTIN
SJ is a 68-year-old male (height 165cm, weight 60kg) admitted to the intensive care unit with shortness of breath and is intubated for acute hypoxic respiratory failure. His past medical history includes hypertension, COPD and type II DM. He quit smoking 10 year ago. He has multiple admissions to the hospital for pneumonia. A culture of his sputum confirms infection by Acinetobacter baumanii susceptible to colistin and amikacin. Based on recent PK data for SJ (creatinine = 86.7 ?mol/L) to target a concentration of 2.5 mg/L, calculate SJ’s loading dose of colistimethate sodium (CMS – a prodrug).
YOU must discuss:
1. The basic pharmacology of colistin (including the mechanism(s) of action and toxicities/adverse effects), its clinical uses and dosages/formulations available.
2. The chemical structure/characteristics of colistin related to its interesting pharmacokinetic characteristics and the clinical implication of these unique features.
3. Considerations that you need to factor in while using colistin in special populations (in renally or hepatically impaired, or in obese patients).
4. RESOVE the case study, showing all calculations/steps to determine your answers.