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Introduction: Classical teaching in laryngoscopy advocates the use of Miller (Straight) blades to be placed underneath the epiglottis and lift it, whereas for Macintosh (Curved) blades the tip is positioned in the vallecula. Published studies in anesthesia suggest that straight blade positioning in the vallecula may be a satisfactory technique for small children. However, there is no clear evidence of consistent implementation of this methodology in practice and associated intubation success. Objectives: To assess laryngoscope blade tip position during pediatric tracheal intubation in the emergency department (ED) and its association with intubation success and time of laryngoscopy. Methods: Single center retrospective observational cohort study. Children undergoing tracheal intubation in a tertiary pediatric ED under video-recorded conditions were eligible for inclusion. A CMAC video laryngoscope was used as first line device with the video feed recorded for review. Videos were reviewed and the blade tip position during intubation recorded by study personnel. Blade tip position was categorized as ‘Correct’ if the curved blade was in the vallecula or straight blade was lifting the epiglottis; otherwise the position was categorized as ‘Incorrect’. Time of laryngoscopy was defined as time from blade insertion to removal. Univariate analysis between covariates was done by Fisher’s exact testing for intubation success and by nonparametric methods for laryngoscopy time. Results: A total of 17 complete videos were included in the study. Mac blade was used correctly in 8/10 cases (80%); Miller was used correctly in 1/7 cases (14%). Among infants (≤ 12 months), the Miller was used incorrectly in 3/4 cases (75%). Intubation was successful in 9/9 cases (100%) with correct blade position and in 5/8 cases (63%) with incorrect position (p=0.04). There was no significant difference in mean calculated laryngoscopy time for correct versus incorrect blade tip position (37.90 ± 26.80 sec vs. 44.33± 15.22 sec, p=0.12) Conclusion: Correct position of the laryngoscope blade tip is associated with higher intubation success. There was no significant difference in the laryngoscopy time for both correct and incorrect blade position.

Background and objective: Difficult airways present a clinical challenge for anaesthetists. The Truphatek Truview EVO2© (Truphatek International Ltd, Netanya, Israel) is a new laryngoscope blade used for endotracheal intubation that could be used where there is difficulty in visualizing the laryngeal inlet. Methods: Twenty anaesthetists (12 trainees and eight consultants) compared the Truphatek Truview EVO2© with a conventional Macintosh size 3 blade. The Trucorp Airsim Bronchi© (Trucorp Ltd, Belfast, Northern Ireland, UK) manikin was intubated under normal conditions and under simulated difficult conditions such as tongue inflation and neck rigidity. In each scenario, the Cormack-Lehane grade, time needed for successful intubation, perceived difficulty of tracheal intubation and personal preference of blade were compared. The results were analysed with t-test (time of intubation), Wilcoxon signed-rank sum (Cormack-Lehane grade, ease of manoeuvre, preferred blade) and analysis of variance with Bonferroni correction (augmentation of difficulties in different scenarios). Results: The Truview EVO2 blade allowed the best laryngeal view as judged by the Cormack-Lehane grade (P < 0.05) in two separate situations: under simulated tongue inflation and under simulated neck rigidity. However, this blade did not reduce the intubation time or the ease of tracheal tube placement with respect to conventional Macintosh blade. Conclusion: Compared with the classical Macintosh blade, the Truview EVO2 blade allowed a better view of the larynx, but did not facilitate endotracheal intubation in any of the difficult scenarios created with the adjustable manikin and in most scenarios in fact prolonged the intubation time.

Background Plastic single-use laryngoscope blades are inexpensive and carry a lower risk of infection compared with metal reusable blades, but their efficiency during rapid sequence induction remains a matter of debate. The authors therefore compared plastic and metal blades during rapid sequence induction in a prospective randomized trial. Methods Two hundred eighty-four adult patients undergoing general anesthesia requiring rapid sequence induction were randomly assigned on a weekly basis to either plastic single-use or reusable metal blades (cluster randomization). After induction, a 60-s period was allowed to complete intubation. In the case of failed intubation, a second attempt was performed using metal blade. The primary endpoint of the study was the rate of failed intubations, and the secondary endpoint was the incidence of complications (oxygen desaturation, lung aspiration, and oropharynx trauma). Results Both groups were similar in their main characteristics, including risk factors for difficult intubation. On the first attempt, the rate of failed intubation was significantly increased in plastic blade group (17 vs. 3%; P < 0.01). In metal blade group, 50% of failed intubations were still difficult after the second attempt. In plastic blade group, all initial failed intubations were successfully intubated using metal blade, with an improvement in Cormack and Lehane grade. There was a significant increase in the complication rate in plastic group (15 vs. 6%; P < 0.05). Conclusions In rapid sequence induction of anesthesia, the plastic laryngoscope blade is less efficient than a metal blade and thus should not be recommended for use in this clinical setting.

Activation of the articulating laryngoscope and external laryngeal manipulation (ELM) improve laryngeal exposure during direct laryngoscopy. We used a head-mounted direct laryngoscopy imaging system and a previously validated scoring system for assessing laryngeal view (the percentage of glottic opening or POGO score) on 33 adult patients undergoing laryngoscopy. On each patient, we videotaped the initial laryngeal exposure (blade not activated), the view with activation of the blade, and the view with operator-directed external laryngeal manipulation. The video recordings were reviewed and the laryngeal view assessed with POGO scores. POGO scores improved with blade activation in 9/33 (27%) of patients vs 28/33 (85%) of patients with ELM. In nearly half of patients studied (16/33, 48%) POGO scores decreased with blade activation. We conclude that ELM is superior to articulating laryngoscope blade activation in improving POGO scores during laryngoscopy on adult patients in standard sniffing position. Using recordings from a direct laryngoscopy video system, we compared laryngeal views in 33 patients with a special articulating laryngoscope blade to views achieved by external laryngeal manipulation (pressing on the patient’s neck). Laryngeal exposure, which is important for placement of tracheal tubes, was better with external laryngeal manipulation.

Coppa and Brodsky (1) described a method to protect the tracheal cuff of a double-lumen tube (DLT) from damage by teeth or by the laryngoscope blade during intubation of the airway. It probably works well, but it seems complicated. Erb (2) described a less difficult method to protect the cuff with a well lubricated teethguard and by lubricating the cuffs of the DLT. There are two other methods to protect the tracheal cuff of a DLT that are simple and require no additional material, help, or effort.

A new laryngoscope blade has been designed for emergency visualization of the pharynx and larynx when the pharyngeal space is restricted. The blade incorporates a 7-cm tube in the distal portion and an intraluminal light source protected from obstruction. It attaches to standard battery-powered light handles, making it practical for emergency use. The new blade has been tested on dogs and used successfully in 12 patients with edematous pharynges and in one patient with a bleeding pharyngeal tumor, where standard non-tubular blades failed to produce a view of the larynx.

SUMMARYA new laryngoscope blade is described which has overcome most of the difficulties of intubation for the writer and therefore has made intubation an easier procedure.