Fanelli G, Casati A
Department of Anesthesiology, IRCCS H. San Raffaele, University of Milan, Italy.
Minerva Anestesiol. 2000 Nov;66(11):811-7.
The cuffed oropharyngeal airway (COPA) has been recently introduced into the market, but few is known about its clinical use in Italy. We therefore conducted a prospective, observational investigation to evaluate the use of this new extra-tracheal airway in clinical practice.
Anesthesiologists participating in the study received a simple questionnaire where data concerning anthropometric variables, surgical procedure, type and doses of drugs used to induce and maintain general anesthesia, type of ventilation during the procedure, and occurrence of untoward events during either COPA placement, general anesthesia maintenance, or postoperative period were prospectively recorded. The number of previously placed COPA, and the adequacy of airway control (subjective four point scale: excellent, good, fair, and poor) were also assessed.
A total of 210 patients (139 female and 71 male) were prospectively studied. General anesthesia was induced with propofol in 204 patients (98%), sodium thiopental in 3 patients (1.5%), and midazolam in 1 patient (0.5%); while only one patient received muscle relaxants (0.5%); 126 patients (64%) were spontaneously breathing while 71 patients (36%) received positive pressure mechanical ventilation. No differences in the incidence of untoward events was reported between spontaneously breathing and mechanically ventilated patients. No differences in the incidence of untoward events were reported according to the number of previously placed COPA. Difficulties in COPA placement were reported in 7 patients with normal dentiture (5%) and 9 patients (39%) with dental prosthesis (p = 0.003), (Odds Ratio: 5.1; Cl95%: 3.0-8.7). Furthermore, airway obstruction was more frequently reported in patients with dental prosthesis (8% vs 0%; p = 0.002). The seal pressure was higher in mechanically ventilated (17 +/- 10 cm H2O) than spontaneously breathing patients (10 +/- 8 cm H2O), (p = 0.0005), while a sealing pressure higher than 12 cm H2O was associated with an increased risk for postoperative sore throat (Odds ratio: 4.3; Cl95%: 2.6-7.1; p = 0.002). Airway control was graded as excellent in 61.4% of cases by physician previously placing more than 50 COPA, compared with only 26.5% when less than 50 COPA had been previously placed (p = 0.0005).
COPA provided as safe and effective airway management in mechanically ventilated patients as that observed during spontaneous breathing. Experience with COPA placement had no effects on the placement success rate or incidence of untoward events, but improved the quality of airway control.
带套囊口咽气道（COPA）最近已投放市场，但在意大利其临床应用情况鲜为人知。因此，我们进行了一项前瞻性观察研究，以评估这种新型气管外气道在临床实践中的应用。
参与研究的麻醉医生收到一份简单问卷，前瞻性记录有关人体测量变量、手术过程、诱导和维持全身麻醉所用药物的类型及剂量、手术期间通气类型以及在放置COPA、全身麻醉维持或术后期间不良事件发生情况的数据。还评估了先前放置COPA的数量以及气道控制的充分性（主观四点量表：优秀、良好、中等和差）。
总共对210例患者（139例女性和71例男性）进行了前瞻性研究。204例患者（98%）使用丙泊酚诱导全身麻醉，3例患者（1.5%）使用硫喷妥钠，1例患者（0.5%）使用咪达唑仑；只有1例患者接受肌肉松弛剂（0.5%）；126例患者（64%）自主呼吸，71例患者（36%）接受正压机械通气。自主呼吸患者和机械通气患者之间不良事件发生率无差异。根据先前放置COPA的数量，不良事件发生率也无差异。7例牙列正常患者（5%）和9例佩戴假牙患者（39%）报告了放置COPA困难（p = 0.003），（比值比：5.1；95%置信区间：3.0 - 8.7）。此外，佩戴假牙患者气道梗阻报告更为频繁（8%对0%；p = 0.002）。机械通气患者的密封压力（17±10 cm H₂O）高于自主呼吸患者（10±8 cm H₂O），（p = 0.0005），而密封压力高于12 cm H₂O与术后咽痛风险增加相关（比值比：4.3；95%置信区间：2.6 - 7.1；p = 0.002）。先前放置超过50个COPA的医生将气道控制评为优秀的病例占61.4%，而先前放置少于50个COPA时这一比例仅为26.5%（p = 0.0005）。
在机械通气患者中，COPA提供的气道管理与自主呼吸时观察到的一样安全有效。放置COPA的经验对放置成功率或不良事件发生率没有影响，但提高了气道控制质量。
