Optimization Dose Study on Pharmacokinetics and Pharmacodynamics of Colistin in Critically Ill Patients

Inclusion Criteria: * More than 60 Kg of weigh * Patients with directed treatment with colistin as the recommended antimicrobial treatment protocols in the hospital to treat some of the following serious infections caused by carbapenems resistant A. baumannii: (i) bacteremia; (ii) nosocomial pneumonia or (iii) infection of skin and soft tissue (cellulitis, abscesses or infected ulcers). * Written informed consent form. Exclusion Criteria: * Refractory shock or other illness with an expectative of life ˂ 48 hours after the recruitment; * Patient declared not to resuscitation maneuvers; * Suspicion or demonstration of endocarditis, osteomyelitis, or meningitis; * Known hypersensitivity to polymyxins; * Pregnancy.