Tobias J D, Flanagan J F, Wheeler T J, Garrett J S, Burney C
Department of Anesthesiology, Vanderbilt University, Nashville, TN 37232.
Crit Care Med. 1994 Nov;22(11):1805-8.
To determine the correlation between end-tidal CO2 and PaCO2 values measured via nasal cannulas in spontaneously breathing children during the perioperative period.
Prospective evaluation.
Pediatric intensive/intermediate care unit in a tertiary care referral center.
Thirty postoperative surgical and trauma patients aged < or = 18 yrs (average age 7.8 yrs [range 6 months to 16 yrs] and average weight 28.3 kg (range 8.5 to 69).
Spontaneously breathing, nonintubated patients with an arterial cannula in place were selected for study. End-tidal CO2 was sampled from nasal cannulas by a sidestream aspirator and was estimated by infrared spectroscopy. The difference between PaCO2 and end-tidal CO2 was compared using linear regression analysis. A total of 55 blood gas measurements were obtained on the 30 patients. The PaCO2 to end-tidal CO2 gradient was < or = 4 torr in 54 of the 55 samples. The mean PaCO2 was 39.5 +/- 3.3 torr (5.27 +/- 0.44 kPa) with a mean end-tidal CO2 value of 39.7 +/- 3.8 torr (5.29 +/- 0.51 kPa). Linear regression analysis of arterial vs. end-tidal CO2 yielded a slope of 0.992 and p = .0001.
End-tidal CO2 measurement by infrared spectroscopy provided an accurate estimation of PaCO2 in this patient population. Its use may limit the need for invasive monitoring and/or repeated arterial blood gas analysis.
确定围手术期自主呼吸儿童经鼻导管测量的呼气末二氧化碳（EtCO₂）与动脉血二氧化碳分压（PaCO₂）值之间的相关性。
前瞻性评估。
三级医疗转诊中心的儿科重症/中级护理单元。
30例年龄≤18岁的术后手术和创伤患者（平均年龄7.8岁[范围6个月至16岁]，平均体重28.3 kg[范围8.5至69 kg]）。
选择有动脉插管且自主呼吸、未插管的患者进行研究。通过旁流吸气器从鼻导管采集呼气末二氧化碳样本，并通过红外光谱法进行估算。使用线性回归分析比较PaCO₂与呼气末二氧化碳之间的差异。对30例患者共进行了55次血气测量。55个样本中有54个的PaCO₂与呼气末二氧化碳梯度≤4 torr。平均PaCO₂为39.5±3.3 torr（5.27±0.44 kPa），平均呼气末二氧化碳值为39.7±3.8 torr（5.29±0.51 kPa）。动脉血与呼气末二氧化碳的线性回归分析得出斜率为0.992，p = 0.0001。
通过红外光谱法测量呼气末二氧化碳可准确估算该患者群体的PaCO₂。其应用可能会减少有创监测和/或重复动脉血气分析的需求。
