Roberts J R, Spadafora M, Cone D C
Department of Emergency Medicine, Mercy Catholic Medical Center, Philadelphia, PA, USA.
Acad Emerg Med. 1995 Jan;2(1):20-4. doi: 10.1111/j.1553-2712.1995.tb03073.x.
To determine whether a certain distance measurement on the oral endotracheal tube (ETT) at the corner of the mouth could reasonably ensure proper depth of placement in critically ill patients, without the immediate need for a confirming chest x-ray (CXR).
A prospective observational cross-sectional design was used to compare ETT mark distance and radiographic location of the ETT tip. The measurement marking on the ETT at the level of the corner of the mouth was noted at the time of intubation. The relationship of the tip of the ETT to the tracheal carina on the postintubation CXR was then determined. The ETT placement was deemed correct if the tip was at least 2 cm cephalad to the carina on the CXR.
Of 83 intubated patients assessed, 52 were men and 31 women. The mean measurement of the ETT at the corner of the mouth was 22.2 cm for the women and 23.1 cm for the men. The mean distance from the tip of the ETT to the carina was 3.45 cm for the women and 4.13 cm for the men. Seventy-five of the 83 patients (90.4%; 95% CI 81.9-95.7%) had correct ETT positions on the initial CXR. If the ETT position had been adjusted at the corner of the mouth to 21 cm for the women and 23 cm for the men, the ETT would have been in correct position for 81 of the 83 patients (97.6%; 95% CI 89.6-95.7%). This represents a significant improvement in tube placement (p < 0.025; the McNemar chi-square).
Proper depth of ETT placement in the critically ill adult patient can be estimated by the technique of this study. In this adult patient population, corner-of-the-mouth placement of the ETT using the 21-cm tube mark for the women and the 23-cm mark for the men would have led to proper placement for most patients.
确定在口角处对气管内导管（ETT）进行特定距离测量是否能合理确保重症患者的导管置入深度合适，而无需立即进行胸部X线（CXR）检查来确认。
采用前瞻性观察性横断面设计，比较ETT标记距离与ETT尖端的影像学位置。在插管时记录口角水平处ETT上的测量标记。然后确定插管后CXR上ETT尖端与气管隆突的关系。如果CXR上尖端至少在隆突上方2 cm，则认为ETT置入正确。
在评估的83例插管患者中，52例为男性，31例为女性。女性患者口角处ETT的平均测量值为22.2 cm，男性为23.1 cm。女性患者ETT尖端到隆突的平均距离为3.45 cm，男性为4.13 cm。83例患者中有75例（90.4%；95%CI 81.9 - 95.7%）在初始CXR上ETT位置正确。如果将口角处的ETT位置调整为女性21 cm、男性23 cm，83例患者中有81例（97.6%；95%CI 89.6 - 95.7%）的ETT将处于正确位置。这代表了导管置入方面的显著改善（p < 0.025；McNemar卡方检验）。
本研究技术可估计重症成年患者ETT的合适置入深度。在该成年患者群体中，使用女性21 cm导管标记、男性23 cm导管标记在口角处放置ETT，对大多数患者来说可实现正确放置。
