Comparison of Enk Fibreoptic Atomizer with translaryngeal injection for topical anaesthesia for awake fibreoptic intubation in patients at risk of secondary cervical injury: A randomised controlled trial

BACKGROUND: Two methods of topical anaesthesia for awake fibreoptic intubation (FOI) in patients at risk of secondary cervical injury were compared: the translaryngeal injection (TLI) technique and the Enk Fibreoptic Atomizer. OBJECTIVE :The objective of this study was to determine which system of topical anaesthesia provides the fastest and most comfortable awake FOI, using the oral approach. DESIGN ;A randomised controlled study. SETTING :A single centre trial between 2009 and 2011. PATIENTS: One hundred and twenty patients (63 women, 57 men) who underwent neurosurgery of the spine at Klinikum St. Georg Leipzig were randomly allocated into two groups (group^TLI, 61 patients; group^ENK-ATOMIZER, 59 patients). Inclusion criteria were an American Society of Anesthesiology (ASA) physical status of 1 to 3, age 18 to 80 years, and those who met any one of three indications for FOI - cervical instability, predicted difficult airway, a BMI greater than 40 kgm^-2, and who gave written informed consent. Exclusion criteria were emergency awake FOI, mental disability/ delirium, polytrauma and contraindication to TLI. INTERVENTIONS :Two anaesthesiologists experienced in both techniques performed all anaesthesia procedures within the study. MAIN OUTCOME MEASURES :The primary outcome was the timing sequence of awake FOI. The incidence of coughing/ gagging, ease of tracheal tube placement, mucosal bleeding, cardiopulmonary stability and postoperative outcomes were also investigated. RESULTS :Awake FOI was significantly faster using the TLI technique (mean, 191 s; range, 123 to 447 s; SD, 83.5) than the Enk Fibreoptic Atomizer [mean, 430 s; range, 275 to 773 s; SD, 124.9; (P<0.0001)]. Patients in groupTLI exhibited significantly less gagging (P=0.047) but more mucosal bleeding (P0.001). CONCLUSION :Awake FOI using the TLI technique was faster and provided better topical anaesthesia with less gagging during endoscopic intubation. However, the TLI technique was also more invasive.