Indications and Contraindications

In its 2003 guidelines for interventional pulmonary procedures, the American College of Chest Physicians (ACCP) left the choice of anesthesia to the interventionalists, depending on the guidelines and resources available at their practice. This was due to the lack of evidence and consensus­ on what are the indications for different types of anesthesia. However general anesthesia was recommended “for rigid bronchoscopy and for pediatric bronchoscopic procedures” [4]. More speci c guidelines on anesthesia for interventional pulmonology were published by the European Respiratory Society and the American Thoracic Society (ERS/ATS) in 2002. These guidelines alerted the interventional bronchoscopists “to be prepared to convert to general anesthesia, if the situation requires (page 358)” and recommended that “the design of the bronchoscopy suite should account for the presence of anesthesia equipment” [5]. It is important to note that the availability of anesthesia support in different practices, especially in nonacademic settings, remains limited. Some facilities have anesthesia support only when procedures are performed in the operating room, and others have anesthesia support in the bronchoscopy suite and/ or the operating room, but some practices have no access to anesthesia support. Under all circumstances, preprocedural evaluation of the patient along with the nature of the procedure and consideration of the available resources should direct the interventionalist to determine the most appropriate form and location of anesthesia needed for a particular procedure.

Preprocedural Evaluation and Preparation

Medical history focused on respiratory and cardiovascular diseases, exercise tolerance, performance status, drug allergy, current medication especially anticoagulants, tobacco, alcohol, or drug use should be documented. Speci c history related to central airway disease such as stridor, hoarseness, snoring and sleep apnea, hemopty-

Table 5.1  ASA physical status

sis, orthopnea, wheezing, and signs of superior vena cava syndrome (SVC) should be elicited. Additionally, anesthesia-related history such as complications of previous sedation and anesthesia, prolonged sedation, unplanned hospital admission, or intubation should be sought. The American Society of Anesthesiologist (ASA) score is commonly assigned to the patient to assess the patient’s physical status and severity of illness; however, the ASA status is not intended to predict anesthesia or procedure-related risk (Table 5.1). Women of childbearing age should be questioned about possibility of pregnancy and counseled regarding effect of anesthesia and the procedure on pregnancy [6].

Physical Examination

The airway should be assessed to determine dif - culty of intubation in case of airway compromise or if rigid bronchoscopy is planned. Direct inspection of pharyngeal structure when the mouth is wide open and the tongue is protruding as far as possible is used to determine the dif culty of intubation by direct laryngoscopy according to the Mallampati classi cation (Fig. 5.1). Other parameters that predict dif cult intubation are: decreased extension of the atlanto-­occipital joint by more than two-third (normally 35 degrees from neutral midline position), decreased mouth opening below the normal range of 50–60 mm, thyromental distance measured in an extended

neck from the mentum to the notch of the thyroid cartilage ≤6 cm in adults, short muscular neck, and receding mandible.

Dental inspection is necessary to identify the presence of loose teeth, dental prosthesis, chipped, missing teeth, bridges, crowns, or dentures that can be dislodged or further damaged during direct laryngoscopy or rigid ­bronchoscopy. The presence of prominent or protruding maxillary incisors may alert the bronchoscopist to the possibility of dif cult intubation.

Respiratory system assessment should be performed with emphasis on baseline saturation,

requirement of supplemental oxygen, and use of accessory respiratory muscle.

Cardiovascular system exam focused on baseline vital signs, signs of cardiovascular compromise due to intrathoracic disease, e.g., superior vena cava syndrome, pericardial effusion.

Laboratory testing should be performed based on the baseline comorbidities and nature of the procedure (e.g., complete blood count, electrolytes, coagulation pro le).

Radiographic studies, e.g., chest X-ray, computed tomography (CT), and electrocardiogram are recommended.