吸入一氧化氮给气系统的应用

Study on the Delivery System of Inhaled Nitric Oxide

目的：研究一种对肺动脉高压患者安全、可靠而有效的一氧化氮（ＮＯ）吸入方法。方法：２０例肺动脉高压患者〔平均肺动脉压大小２．６７ｋＰａ（２０ｍｍＨｇ）〕随机分成４组。每组吸入ＮＯ浓度分别为５ｐｐｍ（１ｐｐｍ＝１／１０＾７）、１０ｐｐｍ、１５ｐｐｍ以及２０ｐｐｍ的ＮＯ１５分钟（使用两种不同方法）。监测吸入前后的平均肺动脉压、平均动脉压、肺循环阻力、体循环阻力、肺内分流值以及吸入气中ＮＯ。

Objective: To develop a safe, accurate, effective, and adaptable system to delivery nitric oxide to patients with pulmonary hypertension. Methods:Twenty patients with pulmonary hypertension (mean pulmonary arterial press ure>20 mmHg)were divided randomly into four groups with nitric oxide delivered at 5,10,15,20 ppm (n=5 in each) for 15 minutes. All patients were mechanically ventilated by 2 different systems. Parameters ineluding mean arterial pressure ,mean pulmonary arterial pressure ,systemic vessel resistance, pulmonary vessel resistance,intra-pulmonary shunt,concentrations of nitric oxide and nitrogen dioxide in the inhaled gas, and blood methemoglobin, etc. were analyzed. Results: Nitrogen dioxide continuously monitored showed<2 ppm with no methemoglobin detected in the blood samples of all patients. Nitric oxide concentrations inhaled remained stable in both of the systems and could be regulated easily and quickly. Nitric oxide decreased mean pulmonary arterial pressure,and pulmonary vessel resistance (p<0.01vs. preinhalation). Changes in mean arterial pressure, systemic vessel resistance,and intra-pulmonary shunt were not significant. Conclusion: Inhaled nitric oxide can be delivered precisely and reliably through the two systems. Nitric oxide can decrease mean pulmonary arterial pressure and pulmonary vessel resistance with low potential toxicity in delivery dose<20 ppm,but without changes in mean arterial pressure,systemic vessel resistance,and intra-pulmonary shunt.