Access to the Internal Cervix Using Simulated Pocket Ultrasound: Observation of Biplane and Monoplane Visualization Techniques

Abstract

Central venous access is the standard for ultrasound because of its advantages in efficacy and safety. In-plane and out-of-plane visualizations are often used, but there is no evidence that one technique is superior to another. The purpose of this study was to compare the success and time required for biplane visualization of in-plane and out-of-plane techniques in simulated models. Ten emergency responders participated in 48 simulated events, alternating visualization techniques for each event. Each event required intravenous cannulation of the simulated model to access the jugular vein, with a maximum of three attempts. Number of attempts required for each event, success rate of puncture and venous cannulation, frequency of posterior wall reorientation and puncture, time required to obtain optimal window, visualization of intravascular needle, and placement of guidewire tooth is recorded. Success rates and times required for each visualization technique were compared. The cannulation success rate was 97% for all three techniques. First attempt success was 94% for bilateral visualization and 97% for plane. The mean total time for the procedure was higher for bilateral visualization (30.2 s) compared with in-plane (27.3 s) and out-of-plane (31 s), but this difference was not statistically significant. There were no significant differences between bilateral visualization and in-plane and out-of-plane techniques in cannulation success, needle redirection, or posterior wall puncture frequency. Further studies with larger samples may be needed to confirm these results.