Superior Venous Access: Single Lumen Midline Catheter vs Ultrasound Guided Peripheral IV as Performed by Bedside Emergency Department Registered Nurses, A Randomized Clinical Trial

Intravenous (IV) access is one of the most frequently performed procedures in emergency medicine and serves as the foundation for many aspects of acute patient care. Reliable vascular access is necessary for laboratory testing, administration of medications and intravenous fluids, contrast-enhanced imaging, blood product transfusion, and other diagnostic and therapeutic interventions. Failure to obtain timely IV access may delay treatment and contribute to prolonged emergency department (ED) length of stay. Difficult intravenous access (DIVA) has been identified as an independent predictor of delayed care and prolonged ED length of stay, making it an important operational and patient safety concern in emergency medicine. Previous studies have suggested that approximately 10% of ED patients have DIVA, while observational data from Albany Medical Center have demonstrated similar rates. Patients with DIVA frequently require multiple attempts at vascular access, which may increase patient discomfort, disrupt clinical workflow, and increase healthcare resource utilization.

Numerous vascular access devices (VADs) are available to manage patients with DIVA. These devices differ in catheter length, insertion technique, location within the vascular system, expected dwell time, and clinical indications. Unlike inpatient settings, where guidance exists for selecting appropriate vascular access devices, there are currently no widely accepted recommendations for vascular access device selection in emergency department patients. Consequently, clinicians often rely on individual experience, local practice patterns, and device availability when selecting a vascular access strategy.

Ultrasound-guided peripheral intravenous catheters are commonly used when traditional landmark-based IV insertion is unsuccessful. Previous investigations have demonstrated that catheter length influences device survival. Shorter catheters placed into deeper veins under ultrasound guidance are associated with shorter dwell times and earlier failure. Prior studies have demonstrated that ultrasound-guided long peripheral IV catheters may fail within hours of insertion and that increasing catheter length may improve catheter survival. These findings suggest that catheter design and insertion technique may play important roles in determining catheter performance.

Single-lumen midline catheters (SLMCs) have emerged as an alternative vascular access device for patients who require intermediate-duration intravenous therapy. Midline catheters are inserted into peripheral veins of the upper extremity and terminate within the axillary venous system. Unlike central venous catheters, midline catheters remain entirely within the peripheral venous system while offering a longer catheter length than traditional peripheral IV catheters. Most midline catheters are inserted under ultrasound guidance and frequently incorporate modified or accelerated Seldinger techniques that may facilitate successful cannulation of deeper veins.

Several characteristics make SLMCs attractive for the management of patients with DIVA. First, previous studies have suggested that midline catheters have substantially longer dwell times than peripheral IV catheters. Published investigations have reported average dwell times of approximately 16 days for midline catheters compared with approximately 5 days for peripheral IV catheters. Second, midline catheters may provide more durable vascular access throughout a patient's hospitalization. Previous studies have demonstrated that many patients who receive a midline catheter do not require any additional vascular access devices during the remainder of their hospital stay. These findings suggest that midline catheters may reduce the need for repeated vascular access procedures after initial insertion. However, relatively little evidence exists regarding the use of these devices in emergency department populations.