LO78: Point-of-care ultrasound compared with manual palpation for the detection of a carotid pulse in live models: a randomized cross-over study

Abstract

Introduction: Pulse check by manual palpation (MP) is an unreliable skill even in the hands of healthcare professionals. In the context of cardiac arrest, this may translate into inappropriate chest compressions when a pulse is present, or conversely omitting chest compressions when one is absent. To date, no study has assessed the utility of B-mode ultrasound (US) for the detection of a carotid pulse. The primary objective of this study is to assess the time required to detect a carotid pulse in live subjects using US compared to the standard MP method. Methods: This is a prospective randomized controlled cross-over non-inferiority trial. Health care professionals from various backgrounds were invited to participate. They attended a 15 minute focused US workshop on identification of the carotid pulse. Following a washout period, they were randomized to detect a pulse in live subjects either by MP first or by US first. Both pulse check methods were timed for each participant on 2 different subjects. The primary outcome measure was time to carotid pulse detection in seconds. Secondary outcome measures included comfort levels of carotid pulse detection measured on a 100mm visual analog scale (VAS), and rates of prolonged pulse checks (greater than 5 or 10 seconds) for each technique. Mean pulse detection times were compared using Students t-test. The study was powered to determine whether US was not slower than MP by greater than 2 seconds. Results: A total of 93 participants completed the study. Time to detect pulse was 4.2 (SD=3.4) seconds by US compared with 4.7 (SD=6.5) seconds by MP (P=0.43). Seventeen (18%) participants took >5 seconds to identify the carotid pulse using US compared to 19 (20%) by MP (P=0.74). Eight (9%) candidates took >10 seconds to identify the pulse using US compared to 9 (10%) by MP (P=0.81). Prior to training, participants had a higher comfort level using MP than US pulse checks (67 vs 26 mm, P<0.001). Following the study, participants reported higher comfort levels using US than MP (88 vs 78 mm, P<0.001). Conclusion: Carotid pulse detection in live subjects was not slower using US as compared to MP in this study. A brief teaching session was sufficient to improve confidence of carotid pulse identification even in those with little to no previous US training. The preliminary results from this study provide the groundwork for larger studies to evaluate this pulse check method for patients in actual cardiac arrest.