title: A novel measurement and delivery system for synchronizing oxygen gas flow with blood flow during cardiopulmonary bypass.
abstract: Monitoring the blood pump and the oxygen gas flow meter are important maneuvers at the initiation of cardiopulmonary bypass (CPB). We present a novel system, designed to improve safety in the heart-lung machine by linking the control of blood flow and the oxygen gas flow meter. This system uses a mass flow controller to provide and control oxygen flow based on the ventilation-perfusion (V/Q) ratio, using the electronic signal of the blood flow. We tested the system, in vitro and in vivo, and examined the resulting level of blood oxygenation. When extracorporeal circulation was initiated, the oxygen flow was instantly linked to the circulating blood flow, providing an adequate V/Q ratio; the partial pressure of oxygen in the blood was maintained at a normal level. Although we have yet to confirm the safety of this system in clinical trials, the new safety assist device can automatically supply oxygen to the oxygenator at the beginning of CPB.
authors: Department of Clinical Engineering, Hiroshima University Hospital, Hiroshima, Japan. okahara@hiroshima-u.ac.jp
authors: S
authors: S
authors: Okahara
authors: S
authors: S
authors: Ninomiya
authors: S
authors: S
authors: Miyamoto
authors: H
authors: H
authors: Takahashi
authors: T
authors: T
authors: Kurosaki
authors: T
authors: T
authors: Sueda
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D004867:Equipment Design; D006355:Heart-Lung Machine; D006439:Hemodynamics; D010100:Oxygen / Q000097:blood*; D010106:Oxygenators; D013552:Swine
chemical_list: D010100:Oxygen
keywords: blood gas control; cardiopulmonary bypass; heart–lung machine; oxygen gas flow; safety