Anaesthesia for Awake Fiberoptic Intubation: Ultrasound-Guided Airway Nerve Block versus Ultrasonic Nebulisation with Lignocaine

Abstract

Background: In anticipated difficult airway, awake fiberoptic guided intubation should be the ideal plan of management. It requires sufficient upper airway anesthesia for patient’s comfort and cooperation. We compared the efficacy of ultrasound guided airway nerve blocks and ultrasonic nebulisation with lignocaine for airway anesthesia before performing awake fibreoptic guided intubation. Methods: This prospective, randomised study included sixty consenting adult patients of both genders (American Society of Anesthesiologists' physical status 1–3) with anticipated difficult airway undergoing surgery. Ultrasound guided airway nerve blocks group received ultrasound-guided bilateral superior laryngeal (1 ml of 2% lignocaine) and transtracheal recurrent laryngeal (2 ml of 2% lignocaine) airway nerve blocks and ultrasonic nebulisation with lignocaine group received ultrasonic nebulisation of 4 ml of lignocaine 4%. The primary outcome was to compare the time required to intubate, whereas the secondary outcomes were to compare cough reflex and gag reflex, hemodynamic changes, number of attempts required, and comfort score during awake fibreoptic guided intubation in both the groups. Results: The time taken for intubation was significantly lower in the ultrasound guided airway nerve blocks group 69.2721.85 s than ultrasonic nebulisation with lignocaine group 92.43  42.90 s (p = 0.015). Hemodynamic variables changed during the procedure but the values were comparable in both groups. There were no statistical differences in cough and gag reflexes, number of attempts, and comfort score in both groups. Conclusions: This study shows that significant lesser time required for performing awake fiberoptic intubation when patient received ultrasound guided airway nerve block in comparison to ultrasonic nebulisation for airway anaesthesia.

Ultrasound-Guided Glossopharyngeal Nerve Block for an Awake Intubation in a Patient Predicted to Have a Difficult Airway: A Case Report

“…The recurrent laryngeal nerve block was performed with a translaryngeal block at the level of the cricothyroid membrane. 3,5…”

“…The recurrent laryngeal nerve block was performed with a translaryngeal block at the level of the cricothyroid membrane. 3,5 One drawback of nerve block techniques in the neck is that they usually require the administration of analgesics and sedatives to reduce the patient's pain and anxiety. In the present patient, intravenous fentanyl was administered for analgesia during the block.…”

“…1,2 During awake intubation, patients may experience discomfort, and multiple reflexes (cough, glottic closure, and/or gag) may be triggered by manipulations inside the oral cavity and pharynx. 3…”

“…4 Nerve blocks include superior laryngeal, recurrent laryngeal, and glossopharyngeal nerve blocks, 4,5 which are usually used in combination. 3,6 A study using a combination of superior laryngeal, recurrent laryngeal, and glossopharyngeal nerve blocks was reported in which a glossopharyngeal neve block was performed using the anatomic landmark technique for a peristyloid approach. 7 We performed ultrasound-guided superior laryngeal, recurrent laryngeal, and glossopharyngeal nerve blocks to facilitate awake intubation in a patient predicted to have a difficult airway.…”

Clinical Application of Ultrasound-Guided Internal Branch of Superior Laryngeal Nerve Block in Patients with Severe COPD Undergoing Awake Fibreoptic Nasotracheal Intubation: A Randomized Controlled Clinical Trial

“…The primary outcomes were the time for intubation (from the beginning of FB insertion through the nostril to successful endotracheal tube placement), adverse reactions, including nausea and vomiting (the nausea and vomiting occurred during and after intubation), cough, body movement (serious body reaction affecting the procedure), hypertension (BP>160/110mmHg), hypotension (BP<90/60mmHg), tachycardia (100>bpm) and bradycardia (HR<60 bpm) and the comfort score (1 = excellent, indicating a calm patient; 2 = good, indicating a comfortable patient; 3 = moderate, there is a need to pacify the patient; 4 = poor, indicating an uncomfortable patient; 5 = agitated patient). 29 The secondary outcomes were hemodynamic changes (MAP and HR) and serum norepinephrine (NE) and adrenaline (AD) concentrations immediately before intubation (T0), immediately after intubation to laryngopharynx (T1); and immediately (T2), 5 min (T3) and 10 min (T4) after intubation. Peripheral venous blood samples (8 mL) were collected in EDTA anticoagulation test tube.…”