A Retrospective Descriptive Study of the Use of Colistin in Khon Kaen Hospital

Abstract

Objective: To evaluate the use of colistin in accordance with prescribed criteria. Methods: A retrospective study was conducted. Data were collected from medical records of in-patients of Khon Kaen Hospital who were admitted between October 2015 and September 2016 and treated with intravenous colistin. The researchers assessed prescribing of colistin in accordance with the criteria set within the hospital. The assessment was in 5 domains including justification of drug use, dosage regimen, process indicator of drug use, management of nephrotoxicity and clinical outcomes. Results: From 623 prescriptions of colistin in 557 patients, the majority were male (67.9%) with an average age of 57 years old, having comorbidities (74.8%), being on ventilator (81.5%), being in intensive care unit (52.2%), and receiving other antimicrobials before colistin was prescribed (94.7%). The most common indication for colistin prescribing was hospital-acquired pneumonia or ventilator (82.2%). 31.2% of prescribing involved the use of colistin with other medications that may cause kidney toxicity. Evaluation of colistin use found that 56.0% of prescribing were documented therapy that started colistin after the results of bacterial culture and antimicrobial sensitivity test were known. 68.2% of prescribing started with loading dose. Colistin dosage was consistent to that specified in criteria (78.5%). An appropriate process monitoring before starting the drug and during drug administration was found in 58.3 to 75.9%. An average duration of colistin used was 10.0±6.6 days. Clinical outcomes improved as per the criteria of the study in 85.1% of patients but the clinical symptoms improved at discharge in 39.3% of patients. Conclusions: The use of colistin in Khon Kaen Hospital was appropriate in terms of indication, prescribing loading dose when starting colistin, amount of loading dose and maintenance dose, process indicator, management of nephrotoxicity and clinical outcomes. However, duration of colistin use was not yet appropriate.