Young Peter J, Pakeerathan Sivarajasingham, Blunt Mark C, Subramanya Sriharsha
Queen Elizabeth Hospital, Kings Lynn, UK.
Crit Care Med. 2006 Mar;34(3):632-9. doi: 10.1097/01.CCM.0000201406.57821.5B.
Leakage of fluid from the subglottic space to the lungs occurs along the longitudinal folds within the wall of an inflated high-volume, low-pressure (HVLP) cuff. The low-volume, low-pressure (LVLP) cuff does not have these folds yet allows for convenient and reliable control of tracheal wall pressure. Pulmonary aspiration during anesthesia has been linked with postoperative pneumonia and during critical illness causes ventilator-associated pneumonia.
Prospective, blinded, randomized controlled trial; prospective observational study; and benchtop models.
Department of Anaesthesia and Critical Care, Queen Elizabeth Hospital.
Anesthetized patients (n=38) and critically ill patients with either an LVLP or HVLP cuffed tracheostomy tube following swallow assessments (n=67).
The LVLP cuff was compared with HVLP cuffs for leakage of dye placed in the subglottic space to the tracheobronchial tree in a rigid tracheal model and a benchtop pig trachea model (before and after a standardized cuff movement).
In the rigid tracheal model, the incidence of leakage was 0% in the LVLP group and 100% in the HVLP group (p<.01). Dye leakage in the pig tracheal model with HVLP cuffs was 44% before tube movement, increasing to 79% afterward. The LVLP cuff did not leak in the pig tracheal model. Dye leakage in anesthetized patients was 0% before movement and 5% after in the LVLP group and in the HVLP group 22% increasing to 67% after movement (p<.001). Forty-nine percent of swallow assessments were scored as failed in the critical care patients with HVLP tracheostomy tube cuffs, and there were no episodes of aspiration following swallow assessment in the LVLP group (p<.05).
The LVLP cuffed tracheal and tracheostomy tubes reduced pulmonary aspiration in the benchtop models and in anesthetized and critically ill patients. The single failure of the LVLP cuff in the anesthesia group was probably associated with accidental endobronchial intubation following tube movement.
声门下间隙的液体沿充气的大容量、低压（HVLP）气管导管壁内的纵向皱襞漏入肺部。小容量、低压（LVLP）气管导管没有这些皱襞，但能方便且可靠地控制气管壁压力。麻醉期间的肺误吸与术后肺炎有关，在危重病期间会导致呼吸机相关性肺炎。
前瞻性、盲法、随机对照试验；前瞻性观察研究；以及体外实验模型。
伊丽莎白女王医院麻醉与重症监护科。
麻醉患者（n = 38）以及吞咽评估后使用LVLP或HVLP带套囊气管造口管的危重病患者（n = 67）。
在硬质气管模型和体外猪气管模型中（在标准化的套囊移动前后），比较LVLP套囊与HVLP套囊，观察置于声门下间隙的染料漏入气管支气管树的情况。
在硬质气管模型中，LVLP组的渗漏发生率为0%，HVLP组为100%（p <.01）。在猪气管模型中，使用HVLP套囊时，套囊移动前染料渗漏率为44%，移动后增至79%。LVLP套囊在猪气管模型中无渗漏。在麻醉患者中，LVLP组移动前染料渗漏率为0%，移动后为5%；HVLP组移动前为22%，移动后增至67%（p <.001）。在使用HVLP气管造口管套囊的危重病患者中，49%的吞咽评估结果为不合格，而LVLP组在吞咽评估后无误吸事件发生（p <.05）。
LVLP带套囊气管导管和气管造口管在体外实验模型以及麻醉和危重病患者中减少了肺误吸。麻醉组中LVLP套囊唯一一次出现问题可能与套囊移动后意外支气管内插管有关。
