Direct Measurement of Nitric Oxide during Experimental Cardiopulmonary Bypass

• Published in: Journal of international medical research Vol. 33; no. 3; pp. 295 - 300
• Main Authors: Hamanaka, S, Tanemoto, K, Inagaki, E, Yamasawa, T, Yoshida, K, Mochizuki, S, Goto, M, Miyasaka, T, Kajiya, F, Tanaka, N
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.05.2005
• Subjects: Animals; Cardiac Surgical Procedures - methods; Cardiopulmonary Bypass - methods; Disease Models, Animal; Extracorporeal Circulation; Extracorporeal Membrane Oxygenation; Nitric Oxide - analysis; Nitric Oxide - chemistry; Nitric Oxide - metabolism; Oxygen - metabolism; Oxygenators; Swine; Thromboembolism - surgery; Cardiopulmonary bypass; Pigs; Low systemic resistance; Nitric oxide sensor; Nitric oxide
• ISSN: 0300-0605; 1473-2300
• DOI: 10.1177/147323000503300304

We developed a system to measure nitric oxide (NO) concentration during cardiopulmonary bypass in anaesthetized pigs (n = 6). A T-shaped connector, attached to an NO sensor, was mounted in the extra-corporeal circuit at two measuring sites: proximal to the membrane oxygenator (venous side) and distal to the arterial line filter (arterial side). After performing a preliminary validation study, we measured plasma NO concentration before and during total cardiopulmonary bypass circulation (non-pulsatile flow 1.5 l/min) and without pulmonary ventilation. After establishing bypass, PaO2 was 318-393 mmHg; when PaO2 was decreased to 80-100 mmHg, plasma NO concentration in the arterial circuit fell by 39.2 ± 15.6 nM. There was no observable change in plasma NO concentration at the venous circuit. This new system could be useful in monitoring NO concentration during cardiac surgery with cardiopulmonary bypass, and for understanding the possible pathophysiological roles of hyper-nitric oxaemia in cardiopulmonary bypass-related cardiovascular complications.