Department of Anesthesiology, the Ottawa Hospital, University of Ottawa, Ottawa, ON, Canada.
J Clin Anesth. 2012 Feb;24(1):19-24. doi: 10.1016/j.jclinane.2011.04.012.
To determine the sensitivity and specificity of direct laryngoscopy in the conscious patient as a diagnostic test for difficult direct laryngoscopy in the unconscious patient.
Prospective case series.
Various operating rooms in a Canadian tertiary-care hospital.
81 ASA physical status 1, 2, and 3 subjects undergoing elective surgery.
A bolus of midazolam was given and a continuous infusion of remifentanil was started and adjusted as needed. Direct laryngoscopy was performed in the conscious subject. No topical anesthesia was applied to the upper airway.
The modified Cormack-Lehane grade was recorded with each subject conscious and unconscious. Other data collected before the intervention included age, gender, height, weight, body mass index, Mallampati class, thyromental distance, mouth opening, previous history of failed or difficult intubation, history of hypertension or obstructive sleep apnea, and routine use of beta blockers. The time of intravenous placement, total dose and duration of remifentanil infusion, and time of endotracheal tube placement were recorded. The lowest oxygen saturation, lowest and highest systolic blood pressure and heart rate, and presence or absence of gagging, coughing, or chest wall rigidity were also noted. Subjects were also asked to complete a questionnaire in the recovery room regarding recall and the degree of discomfort experienced.
43 of 81 subjects were graded 1 or 2a when the laryngoscopy was done in the conscious subject. Six of the 38 subjects who were graded as a difficult laryngoscopy (grade 2b or higher) when they were conscious also remained a difficult laryngoscopy when unconscious and paralyzed. Sensitivity and specificity of direct laryngoscopy in the conscious subject as a diagnostic test for difficult direct laryngoscopy in the unconscious subject were 100% [95% confidence interval (CI) 0.52 to 1] and 57% (95% CI 0.47 to 0.70), respectively.
Using remifentanil as the sole analgesic allows evaluation of the larynx with direct laryngoscopy in a conscious patient. A poor Cormack-Lehane grade in a conscious patient may or may not improve with general anesthesia.
确定清醒患者直接喉镜检查作为无意识患者困难直接喉镜检查的诊断测试的敏感性和特异性。
前瞻性病例系列。
加拿大一家三级保健医院的多个手术室。
81 名ASA 身体状况 1、2 和 3 级接受择期手术的患者。
给予咪达唑仑推注，并开始持续输注瑞芬太尼，并根据需要进行调整。在清醒的受试者中进行直接喉镜检查。上呼吸道未应用局部麻醉。
在意识清醒和无意识的情况下，每位受试者均记录改良的 Cormack-Lehane 分级。干预前收集的其他数据包括年龄、性别、身高、体重、体重指数、Mallampati 分级、甲状软骨-下颌距离、张口度、既往插管失败或困难史、高血压或阻塞性睡眠呼吸暂停史，以及常规使用β受体阻滞剂。记录静脉置管时间、瑞芬太尼输注总剂量和持续时间，以及气管内导管放置时间。还记录了最低血氧饱和度、最低和最高收缩压和心率，以及是否存在呛咳、咳嗽或胸壁僵硬。受试者还在恢复室完成了一份关于回忆和不适感的问卷。
在清醒的受试者中进行喉镜检查时，81 名受试者中有 43 名分级为 1 级或 2a 级。38 名被评为困难喉镜检查（2b 级或更高）的受试者中，有 6 名在意识不清和瘫痪时仍为困难喉镜检查。在无意识和瘫痪状态下，清醒受试者直接喉镜检查作为无意识患者直接喉镜检查困难的诊断测试的敏感性和特异性分别为 100%（95%CI 0.52 至 1）和 57%（95%CI 0.47 至 0.70）。
单独使用瑞芬太尼作为镇痛剂可在清醒患者中使用直接喉镜检查评估喉部。清醒患者的 Cormack-Lehane 分级较差，在全身麻醉下可能会改善，也可能不会改善。
