Evaluation of elementary system of nitric oxide added to sweep gas and auto flow control system for percutaneous cardiopulmonary support

本文研究了在吹扫气中添加一氧化氮（NO）的基本系统的有效性以及分析连续流泵（CFP）电动机电流波形用于自动流量控制的可行性。我们的系统是安全和有用的除湿呼出气体，因为呼出气体中的氮氧化物的值可以保持在安全值以下。NO吸入促使右心室辅助装置（RVAD）的脱机使用猪心脏缺血模型，我们研究了NO对肺动脉系统的影响下，双心室CFP支持。平均肺动脉压保持较低，RVAD流量比（RVAD流量/总体循环流量）可能降低。在双心室支持下吸入NO可预防肺水肿和肺充血。1例CFP支持下患者心功能的评价采用闭合模拟循环，改变心功能、CFP扫频泵速（PS）和监测运动电流波形（MCW）。MCW对PS的行为成为区分前负荷、后负荷和收缩性改变的有用指标。我们认为，通过监测MCW和PS的变化来评价CFP辅助循环下患者的心功能是可行的。PCPS的自动流量控制我们通过分析MCW，设计并验证了PCPS的半自动吸痰回避程序。该程序通过监测MCW来搜索吸入波形信号，并立即降低泵速，直到吸入波形消失。该程序可以拾取所有SW的92.2%。反应时间为3 ~ 5秒，以完全摆脱严重吸吮。

We investigated the usefulness of our elementary system of nitric oxide (NO) added to sweep gas and the feasibility of analyzing motor current wave form of a continuous flow pump (CFP) for auto flow control.Elementary system of NO added to sweep gasWe developed the prototype of elementary system to withdraw the nitrogen oxide from exhaled gas. Our system was safe and useful to dehumidify the exhaled gas because a value of nitrogen oxide in exhaled gas could keep below the safety value.NO Inhalation prompts weaning from the Right Ventricular Assist Device (RVAD)Using porcine cardiac ischemic model, we investigated the effect of NO on pulmonary artery system under biventricular CFP support. Mean pulmonary artery pressure remained low, and the RVAD flow ratio (RVAD flow / total systemic flow) could be reduced. NO inhalation was possible to prevent from lung edema and pulmonary congestion under biventricular support.Estimation of cardiac function of a patient under CFP supportUsing closed-mock circulation, we changed cardiac function, swept pump speed (PS) of CFP and monitored motor current wave form (MCW). The behavior of the MCW against the PS became a useful indicator to distinguish the altered condition of the preload, afterload and contractility. We conclude that it is feasible to estimate cardiac function of patients under circulatory assist with a CFP by monitoring changes of MCW and PS.Auto flow control for PCPSWe produced and examined the semi-automatic sucking evasion program for PCPS by analyzing MCW. The program monitored MCWs to search signal of sucking wave form (SW), and immediately decreased the pump speed until the SW vanished. The program could pick up 92.2 % of all SWs. The reaction time was 3 to 5 seconds to escape from severe sucking completely.