Hensley's Practical Approach to Cardiothoracic Anesthesia

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26. Anesthetic Management for Interventional Pulmonology Procedures

B. Sedation: Monitored Anesthesia Care 1. To facilitate topicalization: Except in rare circumstances with exceptional concern for airway compromise, airway topicalization to facilitate awake fiberoptic intubation is typically performed with some degree of light sedation for patient comfort. Intravenous medications routinely used for this purpose include benzodiazepines such as midazolam; short-acting opioids such as remifentanil infusion; and low-dose nonbenzodiazepine sedative-hypnotics such as ketamine, dexmedetomidine, and propofol. Many of these agents are satisfactory but have different clinical profiles. For example, ketamine-propofol and dexmedetomidine-propofol combinations are both adequate for awake intubation, but the former has a faster onset of sedation, a shorter time to successful intubation, and greater hemodynamic stability. 4 2. As the primary anesthetic: In IP procedures that do not require intubation, such as awake diagnostic bronchoscopy, intravenous sedation is employed to facilitate patient comfort and proceduralist satisfaction. Many of the same agents are used as earlier, with the goal of maintaining not only spontaneous ventilation but also tolerance of the procedure. How ever, combinations are often used; for example, dexmedetomidine bolus and infusion alone were demonstrated to be insufficient for sedation without the need for rescue sedation with midazolam or propofol in many patients. 5 3. Adjuvant regional anesthetic techniques: Regional blocks can be performed in addition to the provision of sedation for medical thoracoscopy. They provide excellent intraopera tive and postoperative analgesia, minimizing pleuritic chest pain and opioid requirements, therefore facilitating respiratory recovery. Epidural or paravertebral anesthesia is the most invasive regional technique. Fascial plane blocks are typically preferred due to their in creased safety profile. Chest wall coverage can be achieved with epidural, paravertebral, midpoint transverse process to pleura, 6 erector spinae, serratus plane, intercostal nerve blocks, or transversus thoracis muscle plane blocks, depending on the procedural or injury site (Figure 26.2). C. General Anesthesia: The use of general anesthesia for IP procedures is increasing, due to advances in bronchoscopy that allow for deeper endobronchial tree access and, therefore, re quire complete immobility of the patient. The incidence of atelectasis under general anesthesia during bronchoscopy is extraordinarily high, close to 90%, and correlates with body mass index (BMI) and duration of anesthesia. 7 Given the detrimental effects of atelectasis on patient ven tilatory status and recovery, as well as on peripheral bronchoscopy efficacy, vigilance for and prevention of atelectasis during bronchoscopy is key. In a multicenter randomized controlled trial, when compared to usual care, endotracheal intubation with a recruitment maneuver, titrated Fio 2 , and a positive end-expiratory pressure (PEEP) of 8-10 cm H 2 O demonstrated a clinically significant decrease in the incidence and extent of atelectasis in patients undergoing bronchoscopy under general anesthesia. 8 These interventions were well tolerated and highly ef fective, and they should be considered for all patients undergoing bronchoscopy under general anesthesia.

CLINICAL PEARL • Prevention of atelectasis is instrumental in avoiding CT-patient divergence. • Most IP cases are done under general anesthesia as outpatient procedures.

III. Procedural Approaches

Copyright © 2024 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. A. Flexible Bronchoscopy 1. Procedure: Visualization of the tracheobronchial tree with a flexible white light broncho scope that allows access to the lower airways including the third order of bronchi. Typically performed in conjunction with one or more other procedures 2 3