Guo Long, Bobhate Prashant, Kumar Shine, Vadlamudi Karunakar, Kaddoura Tarek, Elgendi Mohamed, Holinski Paula, Coe James Y, Rutledge Jennifer, Adatia Ian
Pediatric Cardiac Intensive Care, Mazankowski Alberta Heart Institute, Stollery Children's Hospital, Edmonton, Canada.
Pulmonary Hypertension Service, Mazankowski Alberta Heart Institute, Stollery Children's Hospital, Edmonton, Canada.
Pediatr Cardiol. 2017 Jun;38(5):959-964. doi: 10.1007/s00246-017-1602-0. Epub 2017 Mar 18.
High inspired oxygen concentration (FiO > 0.85) is administered to test pulmonary vascular reactivity in children with pulmonary hypertension (PH). It is difficult to measure oxygen consumption (VO) if the subject is breathing a hyperoxic gas mixture so the assumption is made that baseline VO does not change. We hypothesized that hyperoxia changes VO. We sought to compare the VO measured by a thermodilution catheter in room air and hyperoxia. A retrospective review of the hemodynamic data obtained in children with PH who underwent cardiac catheterization was conducted between 2009 and 2014. Cardiac index (CI) was measured by a thermodilution catheter in room air and hyperoxia. VO was calculated using the equation CI = VO/arterial-venous oxygen content difference. Data were available in 24 subjects (males = 10), with median age 8.3 years (0.8-17.6 years), weight 23.3 kg (7.5-95 kg), and body surface area 0.9 m (0.4-2.0 m). In hyperoxia compared with room air, we measured decreased VO (154 ± 38 to 136 ± 34 ml/min/m, p = 0.007), heart rate (91 [Formula: see text] 20 to 83 [Formula: see text] 21 beats/minute, p=0.005), mean pulmonary artery pressure (41 [Formula: see text] 16 to 35 [Formula: see text] 14 mmHg, p=0.024), CI (3.6 [Formula: see text] 0.8 to 3.3 [Formula: see text] 0.9 L/min/m, p = 0.03), pulmonary vascular resistance (9 [Formula: see text] 6 to 7 [Formula: see text] 3 WU m, p = 0.029), increased mean aortic (61 [Formula: see text] 11 to 67 [Formula: see text] 11 mmHg, p = 0.005), pulmonary artery wedge pressures (11 [Formula: see text] 8 to 13 [Formula: see text] 9 mmHg, p = 0.006), and systemic vascular resistance (12 [Formula: see text] 6 to 20 [Formula: see text] 7 WU m, p=0.001). Hyperoxia decreased VO and CI and caused pulmonary vasodilation and systemic vasoconstriction in children with PH. The assumption that VO remains unchanged in hyperoxia may be incorrect and, if the Fick equation is used, may lead to an overestimation of pulmonary blood flow and underestimation of PVRI.
给予高吸入氧浓度（FiO > 0.85）以检测肺动脉高压（PH）患儿的肺血管反应性。如果受试者呼吸高氧气体混合物，则难以测量氧耗量（VO），因此假设基线VO不变。我们假设高氧会改变VO。我们试图比较在室内空气和高氧环境下通过热稀释导管测量的VO。对2009年至2014年间接受心导管检查的PH患儿获得的血流动力学数据进行回顾性分析。在室内空气和高氧环境下通过热稀释导管测量心脏指数（CI）。使用公式CI = VO/动静脉氧含量差计算VO。有24名受试者（男性10名）的数据可用，中位年龄8.3岁（0.8 - 17.6岁），体重23.3 kg（7.5 - 95 kg），体表面积0.9 m²（0.4 - 2.0 m²）。与室内空气相比，在高氧环境下，我们测量到VO降低（从154±38降至136±34 ml/min/m²，p = 0.007）、心率（从91[公式：见原文]20降至83[公式：见原文]21次/分钟，p = 0.005）、平均肺动脉压（从41[公式：见原文]16降至35[公式：见原文]14 mmHg，p = 0.024）、CI（从3.6[公式：见原文]0.8降至3.3[公式：见原文]0.9 L/min/m²，p = 0.03）、肺血管阻力（从9[公式：见原文]6降至7[公式：见原文]3 WU m²，p = 0.029），平均主动脉压升高（从61[公式：见原文]11升至67[公式：见原文]11 mmHg，p = 0.005）、肺动脉楔压（从11[公式：见原文]8升至13[公式：见原文]9 mmHg，p = 0.006）和体循环血管阻力（从12[公式：见原文]6升至20[公式：见原文]7 WU m²，p = 0.001）。高氧降低了PH患儿的VO和CI，并导致肺血管舒张和体循环血管收缩。高氧环境下VO保持不变的假设可能不正确，如果使用Fick方程，可能会导致肺血流量估计过高和肺血管阻力指数估计过低。
