Safety of Mini-Midline Catheters for Intravenous Antimicrobial Therapy Not Exceeding 14 Days: Treatment Completion Rate and Re-Catheterization Needs.

Abstract

Objective: To evaluate whether ultrasound-guided mini-midline catheter use (8-15 cm) is associated with treatment completion and safety outcomes compared with short peripheral catheters (<8 cm) for intravenous antimicrobial therapy lasting no more than 14 days, while additionally characterizing device specifications, peripheral drug compatibility, and cumulative vascular-access burden.

Methods: This single-center retrospective comparative cohort study included 134 hospitalized adults (55 mini-midline, 79 short PIVC) receiving planned intravenous antimicrobial therapy for 5-14 days. The primary endpoint was treatment completion through the index device. Secondary outcomes included catheter-related complications, re-catheterization, cumulative catheter burden, inflammatory markers, and descriptively summarized dwell time among devices with documented insertion and removal timestamps.

Results: Treatment completion was 46/51 (90.2%) for mini-midlines and 79/79 (100.0%) for short PIVCs (unadjusted p=0.005; absolute RD -9.8%; Holm-adjusted p=0.015). Among devices with documented timestamps, median dwell time was 310.0 hours (12.9 days) for mini-midlines and 71.5 hours (3.0 days) for short PIVCs. Complication rates were low, with 3/55 mini-midline patients experiencing 5 catheter-related events and 0/79 short-PIVC patients experiencing catheter-related events. No bloodstream infection or symptomatic thrombosis occurred in either group. Mini-midline patients required fewer total PIVCs per treatment episode, while cumulative insertion attempts were 61 and 85 in the mini-midline and short-PIVC groups, respectively. Diabetes mellitus and ≥2 puncture attempts were associated with treatment non-completion in the mini-midline group.

Conclusion: Ultrasound-guided mini-midlines were associated with acceptable safety, longer observed peripheral dwell time, and reduced overall PIVC burden in selected hospitalized patients receiving up to 14 days of peripherally compatible intravenous antimicrobial therapy. Mini-midlines should be considered a complementary vascular-access strategy rather than a universal replacement for short PIVCs.