In training emergency physicians the carotid artery Doppler with passive leg raise, does previous sonographic experience influence scan time and competency?

Abstract

Background: Determination of fluid responsiveness (FR) associated with intravascular fluid resuscitation in hypotensive patients poses a challenge, with current best evidence methods fraught with poor retest reliability and difficulty in image acquisition (Osman, Crit Care Med 2007; 35: 64; Marik, Crit Care Med 2009; 37: 2642). Doppler carotid blood flow with passive leg raise (PLR) is a recent modality for determining FR (Marik, Chest 2013; 143: 364). Purpose: This study aimed to determine whether emergency physicians with limited ultrasound experience can reliably acquire this skill. Method: This prospective study recruited 60 emergency physicians with varying experience, who underwent a 3-step learning programme. Participants performed carotid velocity time integral (VTi) Doppler on healthy subjects, followed by repeat measurements in the PLR position. A 16-point checklist and time recorded were assessed for each sonographer, with each participant completing a post-study questionnaire to evaluate perceived competence and ease of skill acquisition. Results: Of the 60 emergency physicians recruited, 37 (61.6%) were inexperienced and 23 (38.4%) were experienced. Against the 16-point assessment, 61% completed assessment without any errors. Fifty-six out of 60 (94.3%) completed the assessment to acceptable standard with errors recognised and corrected, and four participants (6.7%) made critical errors without correction (Figure 1). Average (±SEM) total scan time was 4:52 ± 0:19, with no significant difference found between inexperienced and experienced groups. Conclusions: This study demonstrated feasibility to train emergency physicians, demonstrating that average FR assessment was obtained within 5 min, with no difference between prior experience in scan quality/time taken. 94% completed the scan to acceptable standards, demonstrating ease of carotid Doppler flow with PLR to provide critical information in management of the hypotensive patient.