Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 7 Chung-Shan South Road, Taipei, Taiwan.
Pediatr Neonatol. 2010 Dec;51(6):330-5. doi: 10.1016/S1875-9572(10)60064-2.
Arterial blood gas analysis is the gold standard for assessing the adequacy of ventilation. However, arterial blood sampling may be associated with serious complications in neonates. The aim of the study was to utilize the side-stream capnometry measurement of end-tidal carbon dioxide (PetCO₂) via nasal cannula circuits and to verify the reliability of PetCO₂ in reflecting the arterial blood carbon dioxide(PaCO₂) level in nonintubated neonates.
A retrospective medical record review analysis was performed in nonintubated neonates admitted to the neonatal ward in a medical center. Simultaneous arterial PaCO₂ and PetCO₂ levels were evaluated. PaCO₂ and PetCO₂ levels were compared by paired t test and were correlated using Pearson's correlation. The PetCO₂ bias was defined as the difference between PaCO₂ and PetCO₂, and was assessed by Bland-Altman plot analysis.
A total of 34 neonates were recruited, and data of 54 pairs of PaCO₂ and PetCO₂ levels were available for comparison. The average (mean ± SD) gestational age was 32.5 ± 4.2 weeks, and the average birth weight was 1881 ± 1077 g. There was a good correlation between PetCO₂ and PaCO₂ levels among all paired samples (r = 0.809, p < 0.001). When the data were divided into those with respiratory disease (n = 34) and those without (n = 20), significant correlation between PetCO₂ and PaCO₂ levels were both noted in the former group (r = 0.823, p < 0.001) and the latter group (r = 0.770, p < 0.001). The overall average mean value of PetCO₂ was lower than that of PaCO₂ (39.4 ± 8.8 mmHg vs. 41.3 ± 9.2 mmHg, p = 0.014). The difference between PetCO₂ and PaCO₂ levels was significant only among those with respiratory disease (38.8 ± 9.8 mmHg vs. 41.2 ± 10.3 mmHg, p = 0.027), but not among those without (40.5 ± 7.0 mmHg vs. 41.6 ± 7.2 mmHg, p = 0.289).
End-tidal CO₂ measurement by side-stream capnometry through nasal cannula could provide an accurate and noninvasive estimate of PaCO₂ levels in nonintubated neonates.
动脉血气分析是评估通气充分性的金标准。然而，动脉采血可能与新生儿的严重并发症有关。本研究旨在利用经鼻导管回路的旁流二氧化碳（PetCO₂）测量，验证非插管新生儿的 PetCO₂ 能否可靠反映动脉血二氧化碳（PaCO₂）水平。
对某医疗中心新生儿病房收治的非插管新生儿进行回顾性病历分析。评估同时的动脉 PaCO₂ 和 PetCO₂ 水平。采用配对 t 检验比较 PaCO₂ 和 PetCO₂ 水平，并采用 Pearson 相关分析进行相关性分析。PetCO₂ 偏差定义为 PaCO₂ 与 PetCO₂ 的差值，并通过 Bland-Altman 图分析进行评估。
共纳入 34 例新生儿，可比较 54 对 PaCO₂ 和 PetCO₂ 水平的数据。平均（均数±标准差）胎龄为 32.5±4.2 周，平均出生体重为 1881±1077 g。所有配对样本中，PetCO₂ 与 PaCO₂ 水平均呈良好相关性（r=0.809，p＜0.001）。当将数据分为有呼吸系统疾病（n=34）和无呼吸系统疾病（n=20）两组时，前者（r=0.823，p＜0.001）和后者（r=0.770，p＜0.001）两组中 PetCO₂ 与 PaCO₂ 水平均呈显著相关性。PetCO₂ 的总体平均测量值低于 PaCO₂（39.4±8.8mmHg 与 41.3±9.2mmHg，p=0.014）。仅在有呼吸系统疾病的患者中，PetCO₂ 与 PaCO₂ 水平的差异具有统计学意义（38.8±9.8mmHg 与 41.2±10.3mmHg，p=0.027），而在无呼吸系统疾病的患者中差异无统计学意义（40.5±7.0mmHg 与 41.6±7.2mmHg，p=0.289）。
经鼻导管的旁流二氧化碳测量可提供非插管新生儿 PaCO₂ 水平的准确、无创估计。
