De Vries Jaap W, Plötz Frans B, Van Vught A Johannes
Department of Anesthesia, Intensive Care and Pain, Mesos Medical Center, PO box 8605, 3503 RP Utrecht, The Netherlands.
Intensive Care Med. 2002 Sep;28(9):1336-9. doi: 10.1007/s00134-002-1409-0. Epub 2002 Jul 18.
To evaluate the relationship between the arterial end-tidal partial pressure of carbon dioxide (PCO2) difference (deltapCO2) and the degree of desaturation in children with cyanotic heart disease (CHD) and to come to a more reliable estimation of the arterial carbon dioxide partial pressure (PaCO2) from the end-tidal carbon dioxide partial pressure (PET-CO2).
In part retrospective, in part prospective observational study at a university children's hospital.
We retrospectively assessed the relationship between the arterial oxygen saturation as measured by means of pulse oximetry (SpO2) and the arterial to end-tidal PCO2 differences (deltaPCO2) from the records of medical or surgical interventions in 43 patients with CHD. We derived a PaCO2-PET-CO2 correction formula that was prospectively validated in 34 patients with CHD.
In the retrospective part we found a significant correlation between SpO2 and deltaPCO2 ( r (2)=0.84, p<0.001). The regression equation (corrected PET-CO2=raw PET-CO2-0.36xSpO2+39) was used in the prospective part to calculate the corrected PET-CO2. The r (2)s for the correlations between PaCO(2) and uncorrected and corrected PET-CO2 were 0.17 ( p<0.05) and 0.94 ( p<0.001), respectively. The uncorrected PET-CO2 bias was 13.0 mmHg, the bias +/- 2SDs was -0.1 and 26.2 mmHg. The corrected PET-CO2 bias was -0.6 mmHg, the bias +/- 2SD's was -4.0 and 2.9 mmHg.
Correcting the PET-CO2 for the degree of hypoxia using the SpO2 in artificially ventilated infants and children with CHD results in a clinically applicable estimation of the PaCO2. As both SpO2 and PET-CO2 can be monitored continuously and non-invasively, this could facilitate artificial ventilation management in children with CHD.
评估紫绀型心脏病（CHD）患儿动脉血二氧化碳分压（PCO2）差值（△PCO2）与血氧饱和度降低程度之间的关系，并根据呼气末二氧化碳分压（PET-CO2）更可靠地估算动脉血二氧化碳分压（PaCO2）。
在一所大学儿童医院进行的部分回顾性、部分前瞻性观察研究。
我们回顾性分析了43例CHD患儿医疗或外科干预记录中，通过脉搏血氧饱和度仪（SpO2）测量的动脉血氧饱和度与动脉血和呼气末PCO2差值（△PCO2）之间的关系。我们推导了一个PaCO2-PET-CO2校正公式，并在34例CHD患儿中进行了前瞻性验证。
在回顾性研究部分，我们发现SpO2与△PCO2之间存在显著相关性（r² = 0.84，p < 0.001）。前瞻性研究部分使用回归方程（校正后的PET-CO2 = 原始PET-CO2 - 0.36×SpO2 + 39）计算校正后的PET-CO2。PaCO2与未校正和校正后的PET-CO2之间的相关性r²分别为0.17（p < 0.05）和0.94（p < 0.001）。未校正的PET-CO2偏差为13.0 mmHg，偏差±2SD为-0.1和26.2 mmHg。校正后的PET-CO2偏差为-0.6 mmHg，偏差±2SD为-4.0和2.9 mmHg。
在人工通气的CHD婴幼儿中，使用SpO2对PET-CO2进行缺氧程度校正后，可实现临床上对PaCO2的估算。由于SpO2和PET-CO2均可进行连续无创监测，这有助于CHD患儿的人工通气管理。
