Polymyxin B and doxycycline use in patients with multidrug-resistant Acinetobacter baumannii infections in the intensive care unit.

BACKGROUND: Multidrug-resistant Acinetobacter baumannii (MDR-Ab) has emerged as an increasingly problematic cause of hospital-acquired infections in the intensive care unit (ICU). MDR-Ab is resistant to most standard antimicrobials but often retains susceptibility to polymyxin B and doxycycline. OBJECTIVE: To evaluate the efficacy and toxicity of polymyxin B and doxycycline in the treatment of MDR-Ab infections. METHODS: A retrospective chart review was conducted between March 2002 and May 2005 in patients who received doxycycline or polymyxin B for treatment of MDR-Ab infections in ICUs within Grady Memorial Hospital, Atlanta, GA. RESULTS: Thirty-seven patients with MDR-Ab infections were treated with polymyxin B or doxycycline. Median age was 41 years and median ICU length of stay was 18 days prior to acquisition of MDR-Ab. Clinical cure was observed in 22 of 29 (76%) evaluable patients treated with polymyxin B and 2 of 4 (50%) patients treated with doxycycline. In patients with follow-up cultures, microbiological cure was observed in 17 of 21 (81%) patients treated with polymyxin B and 2 of 3 (67%) patients treated with doxycycline. Nephrotoxicity developed in 21% (7 of 33) of patients who received polymyxin B. Neurotoxicity was observed in 2 (6%) patients who received polymyxin B. No adverse reactions were observed with doxycycline. Overall, crude mortality was 27% (9 of 33) and 75% (3 of 4) among those who received polymyxin B and doxycycline, respectively. Three (9%) deaths were attributed to polymyxin B treatment failure, and no deaths were attributed to doxycycline treatment failure. CONCLUSIONS: Polymyxin B was effectively used to treat a substantial proportion of critically ill patients with MDR-Ab infection and was associated with a similar rate of nephrotoxicity as previously reported. Doxycycline monotherapy was used in a limited number of patients for the treatment of MDR-Ab; further evaluation of its efficacy in larger numbers of patients is warranted.

Use of beta-blockers in patients with COPD.

OBJECTIVE: To evaluate the safety and cardiovascular benefits of beta-blocker therapy in patients with chronic obstructive pulmonary disease (COPD). DATA SOURCES: Clinical literature was accessed through MEDLINE (1966-February 2003). Key search terms included chronic obstructive pulmonary disease and adrenergic beta-antagonists. DATA SYNTHESIS: beta-Blockers are often avoided in patients with COPD because of fear of bronchoconstriction, despite the known cardiovascular mortality benefits. A review of studies evaluating the use of beta-blockers in COPD was undertaken. CONCLUSIONS: The literature supports the safety and mortality benefits of using beta-blockers in COPD. Patients with mild to moderate COPD should receive cardioselective beta-blocker therapy when a strong indication exists.