Wireless blood pressure sensor implantation in sheep: A detailed technique

Abstract

Biomedical research and preclinical testing in large animal models are essential for developing and evaluating new medical devices. This ovine study presents a stepwise implantation protocol and initial experiences with a wireless blood pressure implant sensor, enabling continuous telemetric monitoring in sheep. Adult female Jezersko-Solčava sheep underwent implantation of a wireless blood pressure sensor into the ascending aorta via the right carotid artery. The body of the device can was positioned subcutaneously in the lower neck region. After skin closure, a computed tomography scan was performed to verify sensor tip location. If malposition was detected, surgical revision was undertaken immediately. Wireless blood pressure monitoring was conducted over a 24 h period in a custom-designed sheep barn. Twelve adult female sheep successfully underwent the implantation procedure, with no major complications reported. Sensor catheter revision was required in three animals (25%). The mean duration of the procedure (from incision to skin closure) was 36 ± 10 min. During the 24 h monitoring period, the average systolic and diastolic blood pressures were 93 ± 6 and 65 ± 5 mmHg, respectively. Large animal models, particularly sheep, are indispensable in cardiovascular device research due to their anatomical and physiological similarities to humans. This study demonstrates a rapid, minimally invasive protocol for wireless blood pressure sensor implantation in sheep, offering a valuable platform for chronic telemetric monitoring in the development of cardiovascular medical devices.

Keywords

biomedical research / blood pressure monitoring / large animal model / sheep

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RIGHTS & PERMISSIONS

2026 The Author(s). Animal Models and Experimental Medicine published by John Wiley & Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.