Wratney Angela T, Benjamin Daniel Kelly, Slonim Anthony D, He James, Hamel Donna S, Cheifetz Ira M
George Washington University, Critical Care Medicine, Children's National Medical Center, Washington, DC, USA.
Pediatr Crit Care Med. 2008 Sep;9(5):490-6. doi: 10.1097/PCC.0b013e3181849901.
Endotracheal tube air leak pressures are used to predict postextubation upper airway compromise such as stridor, upper airway obstruction, or risk of reintubation. To determine whether the absence of an endotracheal tube air leak (air leak test >/=30 cm H2O) measured during the course of mechanical ventilation predicts extubation failure in infants and children.
Prospective, blinded cohort.
Multidisciplinary pediatric intensive care unit of a university hospital.
Patients younger than or equal to 18 yrs and intubated >/=24 hrs.
The pressure required to produce an audible endotracheal tube air leak was measured within 12 hrs of intubation and extubation. Unless prescribed by the medical care team, patients did not receive neuromuscular blocking agents during air leak test measurements.
The need for reintubation (i.e., extubation failure) was recorded during the 24-hr postextubation period. Seventy-four patients were enrolled resulting in 59 observed extubation trials. The extubation failure rate was 15.3% (9 of 59). Seven patients were treated for postextubation stridor. Extubation failure was associated with a longer median length of ventilation, 177 vs. 78 hrs, p = 0.03. Extubation success was associated with the use of postextubation noninvasive ventilation (p = 0.04). The air leak was absent for the duration of mechanical ventilation (i.e., >/=30 cm H2O at intubation and extubation) in ten patients. Absence of the air leak did not predict extubation failure (negative predictive value 27%, 95% confidence interval 6-60). The air leak test was >/=30 cm H2O before extubation in 47% (28 of 59) of patients yet 23 patients extubated successfully (negative predictive value 18%).
An endotracheal tube air leak pressure >/=30 cm H2O measured in the nonparalyzed patient before extubation or for the duration of mechanical ventilation was common and did not predict an increased risk for extubation failure. Pediatric patients who are clinically identified as candidates for an extubation trial but do not have an endotracheal tube air leak may successfully tolerate removal of the endotracheal tube.
气管内导管漏气压力用于预测拔管后上呼吸道并发症，如喘鸣、上呼吸道梗阻或再插管风险。确定在机械通气过程中测得的气管内导管无漏气（漏气试验≥30 cm H₂O）是否可预测婴幼儿和儿童的拔管失败。
前瞻性、盲法队列研究。
大学医院的多学科儿科重症监护病房。
年龄小于或等于18岁且插管≥24小时的患者。
在插管和拔管后12小时内测量产生可闻气管内导管漏气所需的压力。除非医疗团队规定，患者在漏气试验测量期间不接受神经肌肉阻滞剂。
记录拔管后24小时内再次插管的需求（即拔管失败）。纳入74例患者，共进行了59次观察到的拔管试验。拔管失败率为15.3%（59例中的9例）。7例患者接受了拔管后喘鸣治疗。拔管失败与通气中位数时间较长有关，分别为177小时和78小时，p = 0.03。拔管成功与拔管后使用无创通气有关（p = 0.04）。10例患者在机械通气期间无漏气（即插管和拔管时≥30 cm H₂O）。无漏气并不能预测拔管失败（阴性预测值27%，95%置信区间6 - 60）。59例患者中有47%（28例）在拔管前漏气试验≥30 cm H₂O，但仍有23例患者成功拔管（阴性预测值18%）。
在未使用肌肉松弛剂的患者中，拔管前或机械通气期间测得的气管内导管漏气压力≥30 cm H₂O很常见，且不能预测拔管失败风险增加。临床上被确定为拔管试验候选者但气管内导管无漏气的儿科患者可能成功耐受气管内导管的拔除。
