Critical Care Trainee, Department of Anaesthesia and Critical Care, Queen Elizabeth Hospital, Kings Lynn, Norfolk, UK, PE30 4ET.
BMC Anesthesiol. 2010 Dec 9;10:21. doi: 10.1186/1471-2253-10-21.
The Lotrach endotracheal tube has a unique low-volume, low-pressure (LVLP) cuff, which has been designed to prevent pressure injury to the tracheal wall. We aimed to estimate the pressure exerted on the tracheal wall by the LVLP cuff and a conventional cuff in a bench-top, clinical and radiological study.
In the bench-top study, a model trachea was intubated with the LVLP cuff and the conventional cuff. The cuff pressure was controlled using a constant pressure device. We assessed the pressure exerted on the tracheal wall by measuring the ability of the cuffs to support a column of water using a standard protocol. In the clinical study, we tested the ability of both cuffs to prevent air leak during a staged recruitment manoeuvre. In the radiological study, we recorded the degree of anatomical distortion of the trachea from both cuffs in the antero-posterior (AP) and transverse tracheal diameters. We performed statistical analysis using non-inferiority tests.
In the bench-top study, the LVLP cuff achieved a plateau at a mean height of 25.2 cmH2O (SD 0.34). In contrast, the conventional cuff failed to maintain any water above the cuff and a plateau could not be measured. In the clinical study, the mean pressure at which air leak occurred was 30.0 +/- 0.8 cmH2O (SD 3.8) using the LVLP cuff and 32.4 +/- 0.7 cmH2O (SD 3.0) using the conventional cuff. In the radiological study, the mean degree of anatomical distortion of the trachea in AP and transverse tracheal diameter was 2.9 +/- 2.2 mm (SD 2.1) and 1.8 +/- 1.4 mm (SD 1.4) using the LVLP cuff and 4.4 +/- 1.3 mm (SD 1.4) and 2.6 +/- 1.5 mm (SD 1.6) using the conventional cuff.
The bench-top and clinical studies both demonstrated that the LVLP cuff exerted approximately 30 cmH2O of pressure on the tracheal wall. These results are supported by our radiological study. We conclude that the LVLP cuff exerts an acceptable amount of pressure on the tracheal wall when it is operated at the recommended intracuff pressure.
Lotrach 气管导管具有独特的低容量、低压力 (LVLP) 套囊，旨在防止气管壁压力损伤。我们旨在通过临床和影像学研究，评估 LVLP 套囊和传统套囊对气管壁的压力。
在台式研究中，使用 LVLP 套囊和传统套囊对模型气管进行插管。使用恒压装置控制套囊压力。我们通过使用标准方案测量套囊支撑水柱的能力来评估套囊对气管壁的压力。在临床研究中，我们测试了两种套囊在分级膨胀操作期间防止漏气的能力。在影像学研究中，我们记录了前后位（AP）和横向气管直径中两种套囊对气管解剖结构变形的程度。我们使用非劣效性检验进行统计分析。
在台式研究中，LVLP 套囊在平均高度 25.2cmH2O（标准差 0.34）时达到平台。相比之下，传统套囊未能维持高于套囊的任何水柱，无法测量平台。在临床研究中，使用 LVLP 套囊发生漏气的平均压力为 30.0 +/- 0.8cmH2O（标准差 3.8），使用传统套囊为 32.4 +/- 0.7cmH2O（标准差 3.0）。在影像学研究中，AP 和横向气管直径的气管解剖结构变形的平均程度分别为 2.9 +/- 2.2mm（标准差 2.1）和 1.8 +/- 1.4mm（标准差 1.4）使用 LVLP 套囊和 4.4 +/- 1.3mm（标准差 1.4）和 2.6 +/- 1.5mm（标准差 1.6）使用传统套囊。
台式和临床研究均表明，LVLP 套囊对气管壁施加约 30cmH2O 的压力。这些结果得到我们的影像学研究的支持。我们得出结论，当 LVLP 套囊在推荐的套囊内压力下操作时，它对气管壁施加的压力在可接受的范围内。
