Goonasekera Chulananda Dias, Goodwin Alison, Wang Yanzhong, Goodman James, Deep Akash
Paediatric intensive care unit, Women's and Children's Division, London, UK.
Division of Health and Social Care Research, King's College London, London, UK.
Indian J Crit Care Med. 2014 Nov;18(11):711-5. doi: 10.4103/0972-5229.144011.
Arterial carbon dioxide tension (PaCO2) is considered the gold standard for scrupulous monitoring in pediatric intensive care unit (PICU), but it is invasive, laborious, expensive, and intermittent. The study aims to explore when we can use end-tidal carbon dioxide tension (PETCO2) as a reliable, continuous, and noninvasive monitor of arterial CO2.
Concurrent PETCO2, fraction of inspired oxygen, PaCO2, and arterial oxygen tension values of clinically stable children on mechanical ventilation were recorded. Children with extra-pulmonary ventriculoatrial shunts were excluded. The PETCO2 and PaCO2 difference and its variability and reproducibility were studied.
A total of 624 concurrent readings were obtained from 105 children (mean age [SD] 5.53 [5.43] years) requiring invasive bi-level positive airway pressure ventilation in the PICU. All had continuous PETCO2 monitoring and an arterial line for blood gas measurement. The mean (SD) number of concurrent readings obtained from each child, 4-6 h apart was 6.0 (4.05). The PETCO2 values were higher than PaCO2 in 142 observations (22.7%). The PaCO2-PETCO2 difference was individual admission specific (ANOVA, P < 0.001). The PaCO2-PETCO2 difference correlated positively with the alveolar-arterial oxygen tension [P(A-a)O2] difference (ρ = 0.381 P < 0.0001). There was a fixed bias between the PETCO2 and PaCO2 measuring methods, difference +0.66 KPa (95% confidence interval: +0.57 to +0.76).
The PaCO2-PETCO2 difference was individual specific. It was not affected by the primary disorder leading to the ventilation.
动脉血二氧化碳分压(PaCO2)被视为儿科重症监护病房(PICU)严格监测的金标准,但它具有侵入性、操作繁琐、费用高昂且为间歇性。本研究旨在探索何时可将呼气末二氧化碳分压(PETCO2)用作动脉血二氧化碳的可靠、连续且无创监测指标。
记录机械通气的临床稳定儿童的同步PETCO2、吸入氧分数、PaCO2及动脉血氧分压值。排除患有肺外脑室-心房分流术的儿童。研究PETCO2与PaCO2的差值及其变异性和可重复性。
从PICU中105名需要有创双水平气道正压通气的儿童(平均年龄[标准差]5.53[5.43]岁)获得了总共624组同步读数。所有儿童均进行了连续PETCO2监测并设有用于血气测量的动脉导管。每个儿童每隔4 - 6小时获得的同步读数的平均(标准差)数量为6.0(4.05)。在142次观察中(22.7%),PETCO2值高于PaCO2。PaCO2 - PETCO2差值因个体入院情况而异(方差分析,P < 0.001)。PaCO2 - PETCO2差值与肺泡-动脉血氧分压差[P(A-a)O2]呈正相关(ρ = 0.381,P < 0.0001)。PETCO2与PaCO2测量方法之间存在固定偏差,差值为 +0.66千帕(95%置信区间:+0.57至 +0.76)。
PaCO2 - PETCO2差值因个体而异。它不受导致通气的原发性疾病影响。