Comparison of different colistin sulfate regimens for carbapenem-resistant gram-negative bacteria pneumonia in neurocritical care patients: a retrospective cohort study

Nosocomial infection caused by carbapenem-resistant gram-negative bacteria (CR-GNB) is a common problem in neurocritical care patients. Clinical evidence suggests that polymyxins have benefits for CR-GNB pneumonia. This study compared the efficacy and safety of different colistin sulfate regimens in CR-GNB pneumonia. Among 133 neurocritical care patients with CR-GNB pneumonia in the intensive care unit (ICU), 24 received nebulized colistin sulfate alone (NC group); 38 received intravenous colistin sulfate alone (IV group); and 71 received nebulized plus intravenous colistin sulfate (NCIV group). After inverse probability of treatment weighting (IPTW), clinical failure rates on days 7 and 14 were significantly higher in the IV group than in the NC group (38.3% vs. 20.5%, <i>P</i> = 0.017 and 32.1% vs. 15.3%, <i>P</i> = 0.004, respectively) and the NCIV group (38.3% vs. 24.7%, <i>P</i> = 0.023 and 32.1% vs. 14.2%, <i>P</i> = 0.015, respectively). Moreover, the IV group also reported a lower microbiological eradication rate on day 14 (<i>P</i> = 0.031) and longer ICU (<i>P</i> = 0.020) and hospital stays (<i>P</i> = 0.037) than the NCIV group. No significant difference in mortality risk and nephrotoxicity among the groups. In multivariable analysis, intravenous colistin sulfate was an independent factor associated with higher clinical failure on day 14 (adjusted odds ratio = 5.92, 95% CI = 1.14-30.84, <i>P</i> = 0.035). Our study suggested that nebulized colistin sulfate with concurrent intravenous administration may be an effective and safe option for CR-GNB pneumonia.