Peripheral intravenous (PIV) cannulation is the most common invasive procedure worldwide and is ubiquitous in emergency medicine, where it is required for blood specimens, fluid administration, and pharmacotherapies. Despite the intervention’s prevalence, obtaining PIV access is often challenging even for experienced practitioners as many emergency department (ED) patients have difficult peripheral venous access due to underlying medical conditions, body habitus, dehydration, or a history of intravenous drug use. Historically, failed PIV access attempts have lead to central venous cannulation though this is costly and results in delays in diagnosis or treatment, and it is generally recognized that peripherally placed lines are not fraught with the litany of complications that centrally placed lines are. For these patients with difficult vascular access, ultrasound has become the contemporary mainstay in facilitating successful cannulation, reliably localizing vasculature and revealing targets that cannot be easily seen or palpated. Initially studied in the ICU setting and reserved for central venous access in critical patients, ultrasound guided cannulation has been shown to have high success rates for obtaining PIV access in various clinical settings, decreases time to cannulation, and limits the number of skin punctures.
Literature has shown that practitioners of varying degree can leverage ultrasound guidance to successfully obtain PIV access when traditional landmark approaches have failed, and do so by employing two primary single-plane techniques: the transverse or short-axis approach, and the longitudinal or long-axis approach. The transverse approach is the faster and more common method whereby the user must “follow the needle tip” by sliding their ultrasound probe across the skin while at the same time advancing the angiocatheter through tissue; a technique that is not initially intuitive and poses a risk of posterior wall vessel perforation. Conversely, the longitudinal method allows good visualization of angiocatheter depth however requires near-perfect catheter-probe parallel alignment throughout the procedure. Recently, biplane imaging (also known as X-plane imaging), which allows simultaneous visualization of both transverse and longitudinal planes, has gained attention and has been incorporated into portable ultrasound devices. This technology has seen regular use by cardiologists to interrogate cardiac structures but has not been routinely studied for vascular access where it could further increase procedural success, efficiency, and safety.
Convissar et al. outlined biplane’s first known vascular access application in the clinical setting through a case report during the COVID-19 pandemic, and further illustrated its utility in a crossover study demonstrating faster, more successful lumen cannulation compared to single-plane imaging when performed by novice ultrasound users with no prior experience in the Surgical ICU setting. To our knowledge, there has been no study evaluating biplane assisted PIV access with practitioners already trained in single-plane techniques. We aim to assess the efficacy of biplane imaging versus standard single-plane imaging in achieving successful PIV cannulation by ultrasound-trained ED nurses. We postulate that employing biplane guidance will result in more rapid and accurate peripheral IV access, improving efficiency and decreasing first-pass failure in the ED setting. Investigating the efficiency of biplane assisted PIV cannulation may provide valuable insights to guide best practices.