Midline catheter tip position and catheter-related complications in antimicrobial therapy: A multi-center randomized controlled trial.

Background: The use of midline catheters (MCs) in intravenous therapy has increased over the last few years; however, scientific evidence is scarce. The recommendations for its specific tip position and safe use in antimicrobial therapy are not well established, which increases the risk of catheter-related complications.

Objective: This study aimed to provide evidence for selecting MC tip positions for safe use in antimicrobial therapy.

Design: This prospective, randomized controlled trial compared catheter-related complications with different tip positions. Participants were assigned to three different catheter tip groups, and the relationship between the tip position and catheter-related complications was observed during antimicrobial therapy.

Setting: Multicenter trial based in intravenous therapy centers at six Chinese hospitals.

Participants: A fixed-point continuous convenience sampling method was used to enroll 330 participants. Three different study groups with equal numbers of participants (n = 110) were established using a randomization technique.

Methods: The incidence of catheter-related complications and catheter retention time was compared among the three groups. The catheter measurement data between the three groups were compared using one-way ANOVA or the Kruskal-Wallis tests. Counting data were compared using chi-square tests, Fisher's exact tests, and Kruskal-Wallis tests. Post-hoc tests were conducted to compare the incidence of complications among the three groups. We followed a time-to-event analysis approach and used Kaplan-Meier curves and log-rank tests to analyze the relationship between catheter-related complications and different tip positions.

Results: The total incidence of catheter-related complications in Experimental Groups 1 and 2 as well as the control group were 10.09%, 17.98%, and 33.73%, respectively. Statistically significant differences existed between the groups (p < 0.0001). In pairwise comparisons of the three groups, significant differences were evident in the incidence of complications between Experimental Group 1 and the control group (RD 19.40%, confidence interval 7.71-31.09). No statistical significance in the incidence of complications between Experimental Group 1 and Experiment Group 2 (RD -4.93%, confidence interval -14.80-4.95) and in the incidence of complications between Experimental Group 2 and the control group (RD 14.47%, confidence interval 1.82-27.12) were noted.

Conclusion: Catheter-related complications were reduced when the tip of the Midline Catheter was located in the subclavian or axillary vein of the chest wall.

Trial Registration: NCT04601597(https://clinicaltrials.gov/ct2/show/NCT04601597). Registration date: September 1, 2020.