Proceedings of The Physiological Society

Physiology 2016 (Dublin, Ireland) (2016) Proc Physiol Soc 37, PCA087

Poster Communications

An enhanced vein physiology practical using Doppler ultrasound imaging

E. Tansey1, S. M. Roe1, C. Johnson1

1. Biomedical Sciences Education, Queen's University Belfast, Belfast, United Kingdom.

Ultrasound technology uses sound waves to visualise body tissues including the vasculature. In this undergraduate medical practical demonstration ultrasound is used as an additional learning tool to aid the understanding of vein physiology. A 30 minute demonstration involving ultrasound investigations of the veins occurred in a 2 hour practical class. Ethical approval was sought and received from Queen's University Belfast. The ultrasound testing was performed by a trained member of academic staff and the test subject was also a staff member. 61 medical students were present in the classroom and completed a Likert scale questionnaire investigating student perception of the value of ultrasound technology in learning about venous pressure. A score of 5 indicated strong agreement while a score of 1 indicated strong disagreement with a statement. Data are expressed as mean ± SEM, paired Student t-tests were performed and p < 0.05 was deemed significant. Images were secured using a Sonoscape portable ultrasound and displayed on overhead projectors to the entire class. Distension of veins in different body regions: The veins above (neck) and below heart level (back of the hand and the feet) were visualised and their level of distension compared, as an indicator of pressure, by observing vessel diameter. The skeletal muscle pump: The subject contracted the leg muscles squeezing blood from adjacent veins towards the heart. The emptying of the veins and their filling when skeletal muscle contraction ceased was observed. Pressure in the veins on the back of the hand: The subject relaxed their arm and allowed the veins to fill up with blood. The arm was then slowly and passively raised. The point at which the veins collapse is an estimate of central venous pressure (CVP). Pressure in the neck veins (jugular venous pressure): The subject performed the Valsalva manoeuvre in a semi-recumbent position. This assessed how jugular venous pressure (as an assessment of CVP) changes in response to increased abdominal pressure. A statistically significant difference was found between students' perceived understanding of the physiology of venous blood pressure before (2.77 ± 0.12) and after (3.95 ± 0.11) the ultrasound demonstration (p<0.001). 89% of students strongly agreed that ‘ultrasound enabled (them) to visualise the factors affecting venous pressure' and 84 % strongly agreed that ‘ultrasound enable (them) to see clinical applications of understanding venous blood pressure'. 88% of students enjoyed the teaching session that incorporated ultrasound and 82% of students strongly agreed that the use of ultrasound in teaching is more effective than conventional methods. Ultrasound enables students to visualise the vasculature and is perceived by students to aid their understanding of venous blood pressure and its clinical significance.

Where applicable, experiments conform with Society ethical requirements