吸入一氧化氮对慢性阻塞性肺疾病继发肺动脉高压患者血流动力学的影响及机理

对１８例慢性阻塞性肺疾病继发肺动脉高压患者行右心漂浮导管术，观察吸入４０ｐｐｍ一氧化氮对患者血流动力学、血气、肺内气体交换、高铁血红蛋白的影响及其与血浆环磷酸鸟苷变化的关系。结果发现，吸入一氧化氮２、８、１５ｍｉｎ时，肺血管阻力分别下降了２８．１％、３１．３％及３４．４％，平均肺动脉压也相应降低（Ｐ均〈０．０１）。停止吸入一氧化氮后２ｍｉｎ，肺血管阻力和平均肺动脉压又恢复至吸入前水平，但吸入一氧化

Effects of Inhaled Nitric Oxide on Hemodynamics and Mechanism in Patients with Chronic Obstructive Pulmonary Disease and Pulmonary Hypertension

Aim To study the effects and mechanism aroused from inhalation of nitric oxide (NO) in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH). Methods The pulmonary and systemic hemodynamics, blood gas exchange, oxygen transportation, guanosine 3'', 5''-cyclic monophosphate (cGMP), and methemoglobin (MetHb) level were measured with Swan-Ganz catheter in 18 patients with COPD-PH before and after inhalation of 40 ppm NO. Results The pulmonary vascular resistance (PVR) was decreased by 28.1%, 31.3% and 34.4%, respectively, meanwhile the mean pulmonary arterial pressure (mPAP) was also decreased after continuous inhalation of NO for 2 min, 8 min and 15 min (P<0.01). Both mPAP and PVR were returned to basic line in 2 min after a stop of inhaled NO. Moreover, few effects of inhaled NO on systemic arterial pressure and systemic vascular resistance was observed. After inhaled NO 15 min, PaO 2 was increased from 6.9±1.5 kPa to 7.8±1.9 kPa, Qs/Qt was decreased from 26%±6% to 20%±7% , and mixed venous cGMP level was increased from 14.6±7.8 pmol/L to 28.9±6.7 pmol/L (P<0.05), but VA/Q, arterial oxygen transport, coefficient of oxygen delivery, and MetHb level were not altered during inhalation of NO. Conclusion The data indicate that the pulmonary blood vessel in COPD-PH can be dilated immediately and selectively, gas exchange in lung can be improved during inhalation of NO , the mechanism of which may be related to increase of cGMP.