Comparison of the UEscope Video Laryngoscope with the Traditional Direct Laryngoscope in Neonates and Infants: A Randomized Clinical Trial

The role of video laryngoscopy in adults is well established, but its role in children is still inconclusive. Previous studies on the UEscope in pediatric patients with difficult airways showed that it could reduce the time to intubation (TTI) compared to a conventional direct laryngoscope. The main objective of the current study was to investigate if the use of the UEscope could reduce the TTI in neonates and infants. Forty patients under 12 months old were recruited from a single tertiary hospital from March 2020 to September 2021 and were randomly assigned to the direct laryngoscope group (n = 19, neonates = 4, infants = 15) or UEscope group (n = 21, neonates = 6, infants = 15). Although the quality of glottic view was comparable in both groups, the TTI was significantly lower in the UEscope group in both the “intention-to-treat” (–19.34 s, 95% confidence interval = –28.82 to –1.75, p = 0.0144) and “as treated” (–11.24 s, 95% confidence interval: –21.73 to 0, p = 0.0488) analyses. The UEscope may be a better choice for tracheal intubation than conventional direct laryngoscope in neonates and infants.

Videolaryngoscopy versus direct laryngoscopy for tracheal intubation in children (excluding neonates)

BACKGROUND

Direct laryngoscopy is the method currently used for tracheal intubation in children. It occasionally offers unexpectedly poor laryngeal views. Indirect laryngoscopy involves visualizing the vocal cords by means other than obtaining a direct sight, with the potential to improve outcomes. We reviewed the current available literature and performed a meta-analysis to compare direct versus indirect laryngoscopy, or videolaryngoscopy, with regards to efficacy and adverse effects.

OBJECTIVES

To assess the efficacy of indirect laryngoscopy, or videolaryngoscopy, versus direct laryngoscopy for intubation of children with regards to intubation time, number of attempts at intubation, and adverse haemodynamic responses to endotracheal intubation. We also assessed other adverse responses to intubation, such as trauma to oral, pharyngeal, and laryngeal structures, and we assessed vocal cord view scores.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and trial registers (www.clinicaltrials.gov and www.controlledtrials) in November 2015. We reran the search in January 2017. We added new studies of potential interest to a list of 'Studies awaiting classification' and will incorporate them into formal review findings during the review update. We performed reference checking and citation searching and contacted the authors of unpublished data to ask for more information. We applied no language restrictions.

SELECTION CRITERIA

We included only randomized controlled trials. Participants were children aged 28 days to 18 years. Investigators performed intubations using any type of indirect laryngoscopes, or videolaryngoscopes, versus direct laryngoscopes.

DATA COLLECTION AND ANALYSIS

We used Cochrane standard methodological procedures. Two review authors independently reviewed titles, extracted data, and assessed risk of bias.

MAIN RESULTS

We included 12 studies (803 children) in this review and meta-analysis. We identified three studies that are awaiting classification and two ongoing studies.Trial results show that a longer intubation time was required when indirect laryngoscopy, or videolaryngoscopy, was used instead of direct laryngoscopy (12 trials; n = 798; mean difference (MD) 5.49 seconds, 95% confidence interval (CI) 1.37 to 9.60; I² = 90%; very low-quality evidence). Researchers found no significant differences between direct and indirect laryngoscopy on assessment of success of the first attempt at intubation (11 trials; n = 749; risk ratio (RR) 0.96, 95% CI 0.91 to 1.02; I² = 67%; low-quality evidence) and observed that unsuccessful intubation (five trials; n = 263) was significantly increased in the indirect laryngoscopy, or videolaryngoscopy, group (RR 4.93, 95% CI 1.33 to 18.31; I² = 0%; low-quality evidence). Five studies reported the effect of intubation on oxygen saturation (n = 272; very low-quality evidence). Five children had desaturation during intubation: one from the direct laryngoscopy group and four from the indirect laryngoscopy, or videolaryngoscopy, group.Two studies (n = 100) reported other haemodynamic responses to intubation (very low-quality evidence). One study reported a significant increase in heart rate five minutes after intubation in the indirect laryngoscopy group (P = 0.007); the other study found that the heart rate change in the direct laryngoscopy group was significantly less than the heart rate change in the indirect laryngoscopy, or videolaryngoscopy, group (P < 0.001). A total of five studies (n = 244; very low-quality evidence) looked at evidence of trauma resulting from intubation. Investigators reported that only two children from the direct laryngoscopy group had trauma compared with no children in the indirect laryngoscopy, or videolaryngoscopy, group.Use of indirect laryngoscopy, or videolaryngoscopy, improved the percentage of glottic opening (five trials; n = 256). Studies noted no significant difference in Cormack and Lehane score (C&L) grade 1 (three trials; n = 190; RR 1.06, 95% CI 0.93 to 1.21; I² = 59%).

AUTHORS' CONCLUSIONS

Evidence suggests that indirect laryngoscopy, or videolaryngoscopy, leads to prolonged intubation time with an increased rate of intubation failure when compared with direct laryngoscopy (very low-quality evidence due to imprecision, inconsistency, and study limitations). Review authors had difficulty reaching conclusions on adverse haemodynamic responses and other adverse effects of intubation, as only a few children were reported to have these outcomes. Use of indirect laryngoscopy, or videolaryngoscopy, might lead to improved vocal cord view, but marked heterogeneity between studies made it difficult for review authors to reach conclusions on this outcome.

Videolaryngoscopy versus direct laryngoscopy for adult patients requiring tracheal intubation

BACKGROUND

Successful tracheal intubation during general anaesthesia traditionally requires a line of sight to the larynx attained by positioning the head and neck and using a laryngoscope to retract the tongue and soft tissues of the floor of the mouth. Difficulties with intubation commonly arise, and alternative laryngoscopes that use digital and/or fibreoptic technology have been designed to improve visibility when airway difficulty is predicted or encountered. Among these devices, a rigid videolaryngoscope (VLS) uses a blade to retract the soft tissues and transmits a lighted video image to a screen.

OBJECTIVES

Our primary objective was to assess whether use of videolaryngoscopy for tracheal intubation in adults requiring general anaesthesia reduces risks of complications and failure compared with direct laryngoscopy. Our secondary aim was to assess the benefits and risks of these devices in selected population groups, such as adults with obesity and those with a known or predicted difficult airway.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase on 10 February 2015. Our search terms were relevant to the review question and were not limited by outcomes. We carried out clinical trials register searches and forward and backward citation tracking. We reran the search on 12 January 2016; we added potential new studies of interest from the 2016 search to a list of 'Studies awaiting classification', and we will incorporate these studies into the formal review during the review update.

SELECTION CRITERIA

We considered all randomized controlled trials and quasi-randomized studies with adult patients undergoing laryngoscopy performed with a VLS or a Macintosh laryngoscope in a clinical, emergency or out-of-hospital setting. We included parallel and cross-over study designs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data, consulting a third review author to resolve disagreements. We used standard Cochrane methodological procedures, including assessment of risk of bias.

MAIN RESULTS

We included 64 studies identified during the 2015 search that enrolled 7044 adult participants and compared a VLS of one or more designs with a Macintosh laryngoscope. We identified 38 studies awaiting classification and seven ongoing studies. Of the 64 included studies, 61 included elective surgical patients, and three were conducted in an emergency setting. Among 48 studies that included participants without a predicted difficult airway, 15 used techniques to simulate a difficult airway. Seven recruited participants with a known or predicted difficult airway, and the remaining studies did not specify or included both predicted and not predicted difficult airways. Only two studies specifically recruited obese participants. It was not possible to blind the intubator to the device, and we noted a high level of inevitable heterogeneity, given the large number of studies.Statistically significantly fewer failed intubations were reported when a VLS was used (Mantel-Haenszel (M-H) odds ratio (OR), random-effects 0.35, 95% confidence Interval (CI) 0.19 to 0.65; 38 studies; 4127 participants), and fewer failed intubations occurred when a VLS was used in participants with an anticipated difficult airway (M-H OR, random-effects 0.28, 95% CI 0.15 to 0.55; six studies; 830 participants). We graded the quality of this evidence as moderate on the basis of the GRADE system. Failed intubations were fewer when a VLS was used in participants with a simulated difficult airway (M-H OR, random-effects 0.18, 95% CI 0.04 to 0.77; nine studies; 810 participants), but groups with no predicted difficult airway provided no significant results (M-H OR, random-effects 0.61, 95% CI 0.22 to 1.67; 19 studies; 1743 participants).Eight studies reported on hypoxia, and only three of these described any events; results showed no differences between devices for this outcome (M-H OR, random-effects 0.39, 95% CI 0.10 to 1.44; 1319 participants). Similarly, few studies reported on mortality, noting no differences between devices (M-H OR, fixed-effect 1.09, 95% CI 0.65 to 1.82; two studies; 663 participants), and only one study reporting on the occurrence of respiratory complications (78 participants); we graded these three outcomes as very low quality owing to lack of data. We found no statistically significant differences between devices in the proportion of successful first attempts (M-H OR, random-effects 1.27, 95% CI 0.77 to 2.09; 36 studies; 4731 participants) nor in those needing more than one attempt. We graded the quality of this evidence as moderate. Studies reported no statistically significant differences in the incidence of sore throat in the postanaesthesia care unit (PACU) (M-H OR, random-effects 1.00 (95% CI 0.73 to 1.38); 10 studies; 1548 participants) nor at 24 hours postoperatively (M-H OR random-effects 0.54, 95% CI 0.27 to 1.07; eight studies; 844 participants); we graded the quality of this evidence as moderate. Data combined to include studies of cross-over design revealed statistically significantly fewer laryngeal or airway traumas (M-H OR, random-effects 0.68, 95% CI 0.48 to 0.96; 29 studies; 3110 participants) and fewer incidences of postoperative hoarseness (M-H OR, fixed-effect 0.57, 95% CI 0.36 to 0.88; six studies; 527 participants) when a VLS was used. A greater number of laryngoscopies performed with a VLS achieved a view of most of the glottis (M-H OR, random-effects 6.77, 95% CI 4.17 to 10.98; 22 studies; 2240 participants), fewer laryngoscopies performed with a VLS achieved no view of the glottis (M-H OR, random-effects 0.18, 95% CI 0.13 to 0.27; 22 studies; 2240 participants) and the VLS was easier to use (M-H OR, random-effects 7.13, 95% CI 3.12 to 16.31; seven studies; 568 participants).Although a large number of studies reported time required for tracheal intubation (55 studies; 6249 participants), we did not present an effects estimate for this outcome owing to the extremely high level of statistical heterogeneity (I2 = 96%).

AUTHORS' CONCLUSIONS

Videolaryngoscopes may reduce the number of failed intubations, particularly among patients presenting with a difficult airway. They improve the glottic view and may reduce laryngeal/airway trauma. Currently, no evidence indicates that use of a VLS reduces the number of intubation attempts or the incidence of hypoxia or respiratory complications, and no evidence indicates that use of a VLS affects time required for intubation.