Context-sensitive airway management.
Context-sensitive airway management.
复制标题
上下文相关的气道管理。
作者：
O. Hung;M. Murphy
Mathew等人在这期《麻醉与镇痛》杂志中提出的病例为我们提供了一个机会，可以从更广泛的角度探讨困难气道管理：首先，情况或背景如何影响我们解决问题的方法;第二，支气管镜插管的“不成文的事实”;第三，气体交换保护对设备和技术的重要性。在汉语中，“危机”的书面语“危机”是由两个独立的词组成的：“危”或“危险”和“机”或“机会”。这种组合很可能起源于古代的教导，教导人们如何在应对不可预测的神秘、政治和环境力量的同时过上繁荣的生活。这种参照系反映了一种根深蒂固的文化生存哲学。历史提供了一个独特的背景，在这个时代有共鸣和反响。换句话说，尽管我们今天的行为往往是由历史塑造的，并以证据为指导，但我们的行动经常受到我们行动的环境（或“背景”）的影响。有人说，我们正处于一场医疗法律“危机”之中。或许，我们应该像中国古人那样，抓住这一“机遇”，同时警惕这一“危机”带来的“危险”。但在这个现代背景下，“机会”是由证据而不是神秘的，环境和政治力量塑造的。Caplan等人在1990年对美国麻醉医师协会（阿萨）已关闭索赔数据库的综述中首次报告了与困难气道管理相关的令人担忧的不良结局。他们报告说，在美国，与呼吸事件相关的不良结局构成了麻醉中最大的一类损伤和诉讼（34%）。该综述还发现，大多数与气道管理相关的不良呼吸结局是可以预防的。认识到扭转这一发现对我们的专业至关重要，阿萨成立了一个工作组来审查现有证据并推荐纠正气道管理策略。阿萨困难气道算法和指南于1993年发布，随后于2003年修订。尽管这些建议存在局限性，但阿萨指南为临床医生提供了一种基于证据的方法来评估和管理即将接受麻醉的患者的气道。虽然很难评估这些指南对临床结局的真正影响，但最近对已关闭索赔数据库的审查显示，有改善的迹象，与气道管理事故相关的不良事件（特别是死亡和脑死亡）数量减少。不幸的是，这种改善仅限于麻醉诱导时的气道管理，而不是手术室外。显然，继续努力提高对困难气道的认识，改善气道评估和教育，加上加强预测和管理策略，是在受控环境中困难气道管理方法的关键。Peterson等人的研究结果还表明，需要对气道管理有更广泛的理解和方法，以改善总体结局。在过去的20年里，许多新的气道设备和技术已经开发出来，这些已经改变了气道实践和管理的景观。此外，气道管理也发生了重大的范式转变，强调气体交换（通气和氧合）超过气管插管。临床医生只使用4种通气和氧合方法：袋式面罩、声门外装置（例如，喉罩导气管）、气管导管和手术导气管。选择这些技术中的一种来提供气体交换不仅取决于最适合患者解剖结构的装置，还取决于临床医生所面临的情况。换句话说，气道管理是“上下文敏感的”，因为它严重依赖于临床情况和环境。例如，如果患者的病史或临床特征预示着使用喉镜进行气管插管“不可能”，并且还具有袋式面罩通气困难和使用声门外装置（如喉罩气道）困难的预测因素，则临床医生在手术室的设置中应谨慎地确保气道清醒，经常使用柔性纤维支气管镜。然而，如果同一患者需要在院前环境、急诊科或磁共振成像室进行气道管理，则管理计划将完全不同，因为技能和有限的资源起着决定性作用。如果患者需要立即和快速的紧急气道干预，如果患者是非常不合作的小孩，或者如果患者是孕妇，气道方法的选择也可能不同。来自加拿大新斯科舍省哈利法克斯伊丽莎白二世女王健康科学中心达尔豪西大学麻醉系。
The case presented by Mathew et al. in this issue of Anesthesia & Analgesia presents us with an opportunity to explore a broader view of difficult airway management: first, how a situation or context influences our approach to the problem; second, the “unwritten truth” of bronchoscopic intubation; and third, the importance of gas-exchange preservation over devices and techniques. In Chinese, the written word for “crisis,” “Wei Ji,” is formed by combining 2 separate words: “Wei” or “danger” and “Ji” or “opportunity.” This combination most likely originated from ancient teachings about how to live a life that thrives while responding to unpredictable mystical, political, and environmental forces. This frame of reference reflects a deep-seated philosophy of cultural survival. History provides a unique context that has resonance and reverberations in this day and age. In other words, although what we do today is often shaped by history and guided by evidence, our actions are frequently tempered by the circumstances (or “context”) in which we act. It has been said that we are in the midst of a medical-legal “crisis.” Perhaps, as the ancient Chinese did, we ought to seize this as an “opportunity,” though alert to the “danger” posed by this “crisis.” But in this modern context, the “opportunity” is shaped by evidence rather than mystical, environmental, and political forces. Caplan et al. first reported alarmingly poor outcomes related to the management of the difficult airway in their review of the American Society of Anesthesiologists (ASA) closed claims database in 1990. They reported that adverse outcomes associated with respiratory events constituted the single largest class of injury, and litigation, in anesthesia in the United States (34%). The review also identified that most of these airway management–related adverse respiratory outcomes were preventable. Recognizing that reversing this finding was paramount to our specialty, the ASA formed a task force to review the existing evidence and to recommend corrective airway management strategies. The ASA Difficult Airway Algorithm and Guidelines were published in 1993 and subsequently revised in 2003. Although there are limitations to the recommendations, the ASA guidelines provide clinicians with an evidence-based approach to the airway evaluation and management of patients about to undergo an anesthetic. Although it is difficult to assess the true impact of these guidelines on clinical outcomes, a recent review of the closed claims database showed that there are signs of improvement, with reduction in the number of adverse events (especially death and brain death) associated with airway management misadventures. Unfortunately, this improvement was limited to the management of the airway on induction of anesthesia, but not outside the operating room. Clearly, continuing efforts to increase awareness of the difficult airway and improve airway assessment and education, coupled with the enhancement of predictive and management strategies, are crucial to the difficult airway management approach in a controlled environment. The findings of Peterson et al. also suggest that a broader understanding and approach to airway management is needed to improve overall outcome. During the last 2 decades, many new airway devices and techniques have been developed, and these have changed the landscape of airway practice and management. In addition, there has been a major paradigm shift in airway management, emphasizing gas exchange (ventilation and oxygenation) over tracheal intubation. Clinicians use only 4 methods of ventilation and oxygenation: a bag mask, an extraglottic device (e.g., a laryngeal mask airway), a tracheal tube, and a surgical airway. Selection of one of these techniques to provide gas exchange depends not only on the devices best suited to the patient’s anatomy but also on the situation faced by the clinician. In other words, airway management is “context sensitive” in that it is heavily dependent on the clinical situation and the environment. If, for instance, a patient presents with a history or clinical features predictive of an “impossible” tracheal intubation using a laryngoscope, and also possesses predictors of difficult bag-mask ventilation and difficulty in using an extraglottic device, such as the laryngeal mask airway, it would be prudent for the clinician in the setting of an operating room to secure the airway awake, frequently utilizing a flexible fiberoptic bronchoscope. However, the management plan would be quite different if this same patient required airway management in the prehospital setting, in the emergency department, or in the magnetic resonance imaging suite where skill sets and limited resources play decisive roles. The selection of an airway approach might also be different if the patient requires immediate and rapid emergency airway intervention, if the patient is a small child who is extremely uncooperative, or if the patient is pregnant. There are From the Department of Anesthesia, Dalhousie University, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada.