Blood sampling via peripheral intravenous access: a three-year retrospective analysis of midline catheter use

Introduction
Blood collection is one of the most common procedures performed in hospitalized patients, essential for diagnosis and monitoring of treatment. While peripheral venipuncture is the standard method, patients with difficult intravenous access may require blood draws from vascular access devices, including midline catheters (MC).

Material and methods
This study aimed to evaluate the effectiveness of using MC for laboratory blood sampling.

Results
Among 1056 cases analyzed, 58.61% (n = 619) of catheter insertions were indicated due to the need for frequent blood draws. In most cases (75.82%, n = 1443), catheters remained in place until the end of intravenous therapy. The average time from hospital admission to catheter insertion was 6.16 days (SD = 10.92), and the mean catheter dwell time was 12.16 days (SD = 10.96), with a median of 9 days. The mean duration of successful using catheters was 9.49 days (SD = 9.70). The proportion of catheters used for blood collection throughout the entire dwell time increased from 41.86% (n = 36) in 2022 to 58.94% (n = 712) in 2024.

Conclusions
The findings highlight the growing role of MC as not only reliable devices for infusion therapy but also safe and effective tools for repeated blood sampling. The increasing aspiration duration and catheter stability support broader implementation of MC in clinical practice, particularly for patients with difficult intravenous access.