RESUMO
Background and Aims: Awake intubation is the preferred method for securing difficult airways. We compared intravenous (IV) propofol and dexmedetomidine for C-MAC® D-blade-guided anticipated difficult nasotracheal intubation under conscious sedation. Methods: This randomised study included 60 patients with difficult airway (El-Ganzouri Score 4-9). After adequate airway preparation with IV midazolam 0.03 mg/kg and IV fentanyl 1 µg/kg, in Group P, propofol was infused at 250 µg/kg/min and in Group D, dexmedetomidine was infused at 1 µg/kg over 10 min, then at 0.5 µg/kg/h till a bispectral index (BIS) value 65-70 was achieved. Patients underwent C-MAC® D-blade video laryngoscope-guided nasotracheal intubation. The intubation score was the primary outcome measure. Secondary outcome measures included haemodynamic parameters, intubation time, number of attempts, the incidence of failed awake intubation, glottic view, time to achieve desired BIS, complications, study drug consumption and patient-reported satisfaction with the awake intubation technique. Quantitative variables were compared between groups using unpaired t-test/Welsch test/Mann-Whitney Test. Qualitative variables were correlated using the Chi-square test/Fisher's exact test. A P value of <0.05 was considered statistically significant. Results: The intubation score was significantly higher in Group D versus Group P (P = 0.007). Patient reaction to intubation, haemodynamic parameters and percentage of glottis opening score were more favourable in Group P. Coughing and vocal cord movement were comparable between the groups (P > 0.05). The time to target BIS was four times longer, and the time to intubate was 6 seconds longer in Group D. Conclusion: Successful awake C-MAC® D-blade video laryngoscopic intubation can be performed under dexmedetomidine/propofol conscious sedation, with propofol giving a better intubation score.
RESUMO
Background: Modifications of curved and straight laryngoscope blades have been used for airway management since a long time. While McCoy blade with an elevated tip is commonly used to intubate patients with anticipated difficult airway, the Miller's straight blade is used for intubations in children and less commonly adults. In this study, we revisit the paraglossal technique of Miller's straight blade as a method to improve laryngeal view especially in difficult intubations. Aim: This study aimed to compare laryngoscopic view and ease of intubation (EOI) using McCoy blade elevated tip and Miller's straight blade paraglossal technique. Materials and Methods: A prospective single-blind study was conducted on 170 patients undergoing elective surgery under general anesthesia. They were randomly allotted to two groups. In Group A, laryngoscopy was performed by Miller's blade paraglossal approach, whereas in Group B, laryngoscopy was performed by McCoy blade with an elevated tip. Laryngeal view was graded using the modified Cormack-Lehane grading, and EOI was graded using EOI score. These were compared with preoperative intubation prediction score. Statistical analysis was done using "Medcalc" version 19.0.3. Numerical and categorical data were analyzed by Student's t-test and Chi-square test, respectively. A P < 0.05 was considered statistically significant. Results: The paraglossal approach with Miller's blade offered better laryngoscopic view as compared with McCoy blade with an elevated tip in normal (54.1% vs. 25.9%) and difficult airway (44.7% vs. 11.8%). Tracheal intubation was easier with McCoy blade with an elevated tip although the success rate of intubation improved with the assistance of a bougie with Miller's straight blade paraglossal approach. Conclusion: The laryngeal view was significantly better with the paraglossal approach of Miller's straight blade even in difficult airway. McCoy blade with an elevated tip was also found to be a useful tool to have in difficult airway, as EOI is significantly higher. The study also highlights the usefulness of adjuncts such as a gum elastic bougie while intubating.