Avoiding incompatible drug pairs in central-venous catheters of patients receiving critical care: an algorithm-based analysis and a staff survey.

Purpose: In a critical care setting, we aimed to identify and solve physico-chemical drug incompatibilities in central-venous catheters considering the staffs' knowledge and assumptions about incompatibilities.

Methods: (i) After positive ethical vote, an algorithm to identify incompatibilities was developed and applied. The algorithm was based on KIK database and Stabilis database, the drug label, and Trissel textbook. (ii) A questionnaire was created and used that asked staff for knowledge and assumptions about incompatibilities. (iii) A 4-step avoidance recommendation was developed and applied.

Results: (i) At least one incompatibility was identified in 64 (61.4%) of 104 enrolled patients. Eighty one (62.3%) of 130 incompatible combinations affected piperacillin/tazobactam and in 18 (13.8%) each furosemide and pantoprazole. (ii) 37.8% (n = 14) of the staff members participated in the questionnaire survey (median age: 31, IQR: 4.75 years). The combination of piperacillin/tazobactam and pantoprazole was incorrectly judged to be compatible by 85.7%. Only rarely felt the majority of respondents unsafe in administering drugs (median score: 1; 0, never to 5, always). (iii) In those 64 patients with at least one incompatibility, 68 avoidance recommendations were given, and all were fully accepted. In 44 (64.7%) of 68 recommendations "Step 1: Administer sequentially" was suggested as a avoidance strategy. In 9/68 (13.2%) "Step 2: Use another lumen", in 7/68 (10.3%) "Step 3: Take a break", and in 8/68 (11.8%) "Step 4: Use catheters with more lumens" were recommended.

Conclusions: Although incompatibilities were common, the staff rarely felt unsafe when administering drugs. Knowledge deficits correlated well with the incompatibilities identified. All recommendations were fully accepted.