Feasibility and Efficacy of Teaching Patients Self-Assessment of Inferior Vena Cava Operating a Portable Ultrasound Device - The 65th Annual Conference of the Israel Heart Society & The Israel Society of Cardiothoracic Surgery, 24-25 April 2018

Osnat Ganz Department of Epidemiology, Faculty of Health Sciences. Ben Gurion University of the Negev, Beer Sheva, Israel Alon Ben-Sasson Department of Epidemiology, Faculty of Health Sciences. Ben Gurion University of the Negev, Beer Sheva, Israel Iotam Lior Department of Epidemiology, Faculty of Health Sciences. Ben Gurion University of the Negev, Beer Sheva, Israel Noah Liel Cohen Department of Epidemiology, Faculty of Health Sciences. Ben Gurion University of the Negev, Beer Sheva, Israel Cardiology Department, Soroka University Medical Center, Beer Sheva, Israel Sergio Kobal Department of Epidemiology, Faculty of Health Sciences. Ben Gurion University of the Negev, Beer Sheva, Israel Cardiology Department, Soroka University Medical Center, Beer Sheva, Israel

Background: The size and respiratory variation of inferior vena cava (IVC) is an efficient surrogate of the intravascular volume and is assessed by ultrasound. We hypothesize that patients can assess their IVC after a brief training. We aim to assess the feasibility and efficacy of teaching self-examination of the IVC to a general population.

Methods: Healthy volunteers received 30 minute lecture followed by 30 minutes of hands-on practice on self-examination of the IVC operating a pocket-size ultrasound device. After a week, the volunteers were asked to perform a self-study of the IVC; a second study was done by a cardiologist blinded to the volunteers results. Another cardiologist performed measurements of the IVC size on the recorded clips and assessed also the respiratory variation. The scoring was: 0 for no image provided and one point for each of the following conditions: faint image but unable to performed meassurements, an image able to assess IVC respiratory variation, an image able to measure IVC size. The scores ranged from 0 to 3.

Results: The study included 30 volunteers, aged 54 ± 21 years, 65% females. After the practical training 2 volunteers refused to continue with the study. Volunteer and cardiologist scores of the IVC images were 2.2 ± 0.8 and 2.8 ± 0.1. respectively (p= 0.16). There were 18 volunteers ≥ 65 years; their score was 1.4 ± 0.6, lower than the volunteers under 65 years: 2.3 ± 0.3 (p= 0.027). In those cases (17 out of 28) that IVC size could be measured from the images obtained by the volunteers and cardiologist, the correlation was good (0.69). IVC respiratory variation was evaluable in 25/28 cases done by the cardiologist and in 13/28 self-studies.

Conclusions: The feasibility of teaching an adult population the ultrasound technique of self-assessment of the IVC after a brief training is high. Advanced age adversely influenced the IVC image quality. Evaluation of IVC size by an independent reader of self-performed ultrasound is possible with an acceptable precision.