Day R W, Barton A J, Pysher T J, Shaddy R E
Division of Pediatric Cardiology, Primary Children's Medical Center, University of Utah, Salt Lake City 84113, USA.
Ann Thorac Surg. 1998 May;65(5):1400-4. doi: 10.1016/s0003-4975(98)00234-3.
We have empirically used supplemental nitrogen in newborns with a functional single ventricle and ductal-dependent systemic perfusion to prevent pulmonary vasodilation and deliver a greater proportion of flow to the systemic circulation. Thus, we reviewed patient outcome to determine whether adverse pulmonary vascular effects may be associated with this therapy.
From December 1991 to December 1995, the fraction of inspired oxygen was adjusted, with supplemental nitrogen if necessary, to maintain an oxygen saturation near 75% in 20 newborns awaiting heart transplantation. Medical records were reviewed to evaluate (1) the duration of nitrogen therapy, (2) pulmonary vascular histology, (3) postoperative pulmonary hemodynamics, and (4) survival.
Thirteen patients underwent heart transplantation, 4 patients died without surgical intervention, and 3 patients underwent late aortic reconstruction. Supplemental nitrogen was used without exceeding a fraction of inspired oxygen of 0.21 for 38 +/- 6 days. One patient had evidence of changes of potentially irreversible pulmonary vascular disease. Pulmonary vascular resistance was not increased long-term in surviving patients.
Supplemental nitrogen can be used to maintain a systemic oxygen saturation near 75% for an extended period in newborns with ductal-dependent systemic perfusion with no long-term adverse effect on pulmonary vascular resistance.
我们已根据经验，对具有功能性单心室和依赖动脉导管进行体循环灌注的新生儿使用补充氮气，以防止肺血管扩张，并使更大比例的血流进入体循环。因此，我们回顾了患者的预后情况，以确定这种治疗方法是否可能会产生不良的肺血管效应。
从1991年12月至1995年12月，对20名等待心脏移植的新生儿调整吸入氧分数，必要时使用补充氮气，以维持氧饱和度接近75%。查阅病历以评估：（1）氮气治疗的持续时间；（2）肺血管组织学；（3）术后肺血流动力学；（4）生存率。
13例患者接受了心脏移植，4例患者未接受手术干预即死亡，3例患者接受了晚期主动脉重建术。补充氮气的使用时间为38±6天，吸入氧分数未超过0.21。1例患者有潜在不可逆性肺血管疾病改变的证据。存活患者的肺血管阻力未长期增加。
对于依赖动脉导管进行体循环灌注的新生儿，补充氮气可长期用于维持体循环氧饱和度接近75%，且对肺血管阻力无长期不良影响。
