Videolaryngoscopy versus direct laryngoscopy for nasotracheal intubation: A systematic review and meta-analysis of randomised controlled trials

Does intubation while observing the glottis with a fiberoptic scope reduce postoperative sore throat?

INTRODUCTION

In oral maxillofacial surgery, the nasal tracheal tube is mostly used to provide a better surgical field for oral, head and neck operations. Postoperative sore throat and hoarseness are common following tracheal intubation, with an incidence of 11-55%. Then, we previously reported advantage technique of fiberoptic scope to decrease the risk which the tip of the tube is visualized as the tube is advanced which helps avoid impingement of the tube. However, the extent to which this technique causes postoperative complications is unknown compared to traditional technique. The aim of this study was retrospectively to determine the effect of postoperative sore throat following nasotracheal intubation by tip of the tube is visualized by fiberoptic scope.

METHOD

Anesthesia records of the adult patients with nasotracheal intubation were checked. Patients underwent oral maxillofacial surgery from January 2021 until March 2023. Facilitated with rocuronium, nasotracheal intubation was performed using the traditional or observative method by fiberoptic scope with a 4.8 mm outer diameter. Intubation was performed with a cuffed 6.5-8.0 mm ID nasotracheal tube. The following variables were recorded: gender, age, height, weight, ASA classification, anesthesia time, duration of intubation, tube size, intubation attempts, fentanyl and remifentanil. The postoperative sore throat and the incidence of hoarseness were recorded at operative day and at the day after operative day, and the time to recovery.

RESULT

A total of 104 cases (traditional fiberoptic intubation n = 51, observative fiberoptic intubation n = 53) were enrolled in this retrospective study. There were no significant differences in clinical characteristics and anesthetic data. There was not significant difference in incidence of postoperative sore throat, hoarseness and recovery between the two groups (P = 0.61, 0.44, 0.90). For subjects reporting postoperative sore throat (n = 30), there was not a significant difference in VAS means at operative day and at the day after operative day between the two groups (P = 0.81, 0.91).

CONCLUSION

We found that postoperative sore throat and recovery were not influenced by observative fiberoptic scope for nasotracheal intubation.

A comparative evaluation of fibreoptic bronchoscopy versus C-MAC® D-BLADE-guided videolaryngoscopy for nasotracheal intubation under general anesthesia in oropharyngeal carcinoma surgery patients

PURPOSE

Nasotracheal intubation (NTI) is required for surgery in oropharyngeal (OP) carcinoma patients, but it may be challenging because of distorted anatomy, mucosal congestion, and increased risk of bleeding. Flexible bronchoscopy (FB)-guided NTI is preferred in these cases but has limitations. In this randomized controlled study, we sought to compare C-MAC® D-BLADE-guided videolaryngoscopy (VL) (Karl Storz SE & Co. KG, Tuttlingen, Germany) with FB for NTI under general anesthesia in patients with OP carcinomas.

METHODS

We randomized a total of 100 patients with OP carcinoma and El-Ganzouri's risk index (EGRI) < 7 to undergo NTI under general anesthesia with FB (n = 50) or C-MAC D-BLADE-guided VL (n = 50). The primary outcome was the total intubation time. We also recorded the time to glottis view, nasal intubation difficulty scale (NIDS) score, best percentage of glottis opening score, and complications.

RESULTS

The median [interquartile range (IQR)] total intubation time was shorter with VL than with FB (total intubation time, 38 [26-43] sec vs 60 [52-65] sec; difference, -20 sec [95% confidence interval (CI), -27 to -11]; P < 0.001). Similarly, the median [IQR] time to glottis view was shorter with VL compared to FB (8 [6-9] sec vs 22 [14-25] sec; difference, -13 sec [95% CI, -17 to -10]; P < 0.001). The median NIDS score was higher with VL (difference, 2 [95% CI, 2 to 3]; P < 0.001). The incidences of airway trauma (two cases with FB vs seven with VL; P = 0.30) and postoperative sore throat (ten cases in both groups; P = 0.56) were similar.

CONCLUSION

Compared to FB, C-MAC D-BLADE-based VL reduced the total time for nasal intubation oropharyngeal carcinoma patients, potentially representing an acceptable alternative in selected cases.

TRIAL REGISTRATION

CTRI.nic.in (2018/11/0162830); first submitted 8 November 2018.

Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR), Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management. Part II

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.

Glidescope Video Laryngoscopy in Patients with Severely Restricted Mouth Opening-A Pilot Study

BACKGROUND

An inter-incisor gap <3 cm is considered critical for videolaryngoscopy. It is unknown if new generation GlideScope Spectrum™ videolaryngoscopes with low-profile hyperangulated blades might facilitate safe tracheal intubation in these patients. This prospective pilot study aims to evaluate feasibility and safety of GlideScopeTM videolaryngoscopes in severely restricted mouth opening.

METHODS

Feasibility study in 30 adults with inter-incisor gaps between 1.0 and 3.0 cm scheduled for ENT or maxillofacial surgery. Individuals at risk for aspiration or rapid desaturation were excluded.

RESULTS

The mean mouth opening was 2.2 ± 0.5 cm (range 1.1-3.0 cm). First attempt success rate was 90% and overall success was 100%. A glottis view grade 1 or 2a was achieved in all patients. Nasotracheal intubation was particularly difficult if Magill forceps were required (n = 4). Intubation time differed between orotracheal (n = 9; 33 (25; 39) s) and nasotracheal (n = 21; 55 (38; 94) s); p = 0.049 intubations. The airway operator's subjective ratings on visual analogue scales (0-100) revealed that tube placement was more difficult in individuals with an inter-incisor gap <2.0 cm (n = 10; 35 (29; 54)) versus ≥2.0 cm (n = 20; 20 (10; 30)), p = 0.007, while quality of glottis exposure did not differ.

CONCLUSIONS

GlidescopeTM videolaryngoscopy is feasible and safe in patients with severely restricted mouth opening if given limitations are respected.

Recent Advances in Videolaryngoscopy for One-Lung Ventilation in Thoracic Anesthesia: A Narrative Review

Since their advent, videolaryngoscopes have played an important role in various types of airway management. Lung isolation techniques are often required for thoracic surgery to achieve one-lung ventilation with a double-lumen tube (DLT) or bronchial blocker (BB). In the case of difficult airways, one-lung ventilation is extremely challenging. The purpose of this review is to identify the roles of videolaryngoscopes in thoracic airway management, including normal and difficult airways. Extensive literature related to videolaryngoscopy and one-lung ventilation was analyzed. We summarized videolaryngoscope-guided DLT intubation techniques and discussed the roles of videolaryngoscopy in DLT intubation in normal airways by comparison with direct laryngoscopy. The different types of videolaryngoscopes for DLT intubation are also compared. In addition, we highlighted several strategies to achieve one-lung ventilation in difficult airways using videolaryngoscopes. A non-channeled or channeled videolaryngoscope is suitable for DLT intubation. It can improve glottis exposure and increase the success rate at the first attempt, but it has no advantage in saving intubation time and increases the incidence of DLT mispositioning. Thus, it is not considered as the first choice for patients with anticipated normal airways. Current evidence did not indicate the superiority of any videolaryngoscope to another for DLT intubation. The choice of videolaryngoscope is based on individual experience, preference, and availability. For patients with difficult airways, videolaryngoscope-guided DLT intubation is a primary and effective method. In case of failure, videolaryngoscope-guided single-lumen tube (SLT) intubation can often be achieved or combined with the aid of fibreoptic bronchoscopy. Placement of a DLT over an airway exchange catheter, inserting a BB via an SLT, or capnothorax can be selected for lung isolation.

Cuff inflation technique is better than Magill forceps technique to facilitate nasotracheal intubation guiding by GlideScope® video laryngoscope

Video laryngoscopy is often selected to assist nasotracheal intubation in allowing better laryngeal visualization, although there is no comparative study evaluating the effectiveness between auxiliary techniques by using Magill forceps and inflated cuff in GlideScope video laryngoscopy for nasotracheal intubation. Fifty-one of 100 patients in a Magill forceps group and 47 of 100 patients in a cuff inflation group were included in the final analysis in this randomized, single-blind, parallel, clinical trial study. Induction agents were routinely administered according to body weight, while intubation time spent, attempts, and related side effects were recorded. Compared to the Magill forceps group, the cuff inflation technique shortened the total intubation time (70.0 ± 24.5 s vs. 87.0 ± 25.0 s, p = 0.001) and the time of advancing the nasotracheal tube from oropharyngeal space into the trachea (25.9 ± 16.4 s vs. 42.3 ± 21.2 s, p < 0.001). However, the number of intubation attempts was not significantly different between groups. During tube advancement, the tube was rotated to accommodate the glottis and trachea more frequently in the cuff inflation group (p = 0.009), but the blade of the laryngoscope shifted and was adjusted to the proper position more frequently in the Magill forceps group (p < 0.001). In the Magill forceps group, the tube cuff might be clipped incidentally and the intubator might shift their gaze away from the screen during intubation, although there was no significant difference in intubation-related side effects between groups. Unlike the conventional approach, nasotracheal intubation with the GlideScope® video laryngoscope using the auxiliary technique of cuff inflation could be more suited than using Magill forceps.

A Comparison of McGrath Videolaryngoscope versus Macintosh Laryngoscope for Nasotracheal Intubation: A Systematic Review and Meta-Analysis

Background: In this study, it was shown that the routine use of McGrath videolaryngoscopy may improve intubation success rates. The benefits to using a videolaryngoscope in nasotracheal intubation were also demonstrated. However, no solid evidence concerning the effectiveness of the use of McGrath videolaryngoscopes in nasotracheal intubation has previously been reported. As a result, we questioned whether, in adult patients who underwent oral and maxillofacial surgeries with nasotracheal intubation (P), the use of a McGrath videolaryngoscope (I) compared with a Macintosh laryngoscope (C) could reduce the intubation time, improve glottis visualization to a score of classification 1 in the Cormack–Lehane classification system, and improve the first-attempt success rate (O). The secondary outcomes measured were the rate of the use of Magill forceps and the external laryngeal pressure (BURP) maneuver used. Methods: An extensive literature search was conducted using databases. Only randomized controlled trials that compared the McGrath videolaryngoscopy and Macintosh laryngoscopy techniques in nasotracheal intubation in adult patients were included. Results: Five articles met the inclusion criteria and were included in the final analysis (n = 331 patients). The results showed a significant decrease in intubation time and a higher rate of classification 1 scores in the Cormack–Lehane classification system, but no difference in the first-attempt success rates were found between the McGrath group and the Macintosh group. Decreases in the rate of the use of Magill forceps and the use of the external laryngeal pressure maneuver were also found in the pooled analysis. With regard to the overall risk of bias, the selected trials were classified to have at least a moderate risk of bias, because none of the trials could blind the operator to the type of laryngoscope used. Conclusions: Our analysis suggests that the use of a McGrath videolaryngoscope in nasotracheal intubation resulted in shorter intubation times, improved views of the glottis and similar first-success rates in adult patients who received general anesthesia for dental, oral, maxillofacial, or head and neck cancer surgery, and also reduced the use of Magill forceps and the BURP maneuver.

Video laryngoscopy vs. direct laryngoscopy for nasotracheal intubation in oro-maxillofacial surgery: a systematic review and meta-analysis of randomized controlled trials

Background

Nasotracheal intubation (NTI) is commonly performed in oromaxillofacial surgeries. We did this meta-analysis to ascertain whether use of video laryngoscopy (VL) provided better NTI characteristics as compared to direct laryngoscopy (DL) in patients undergoing oromaxillofacial surgeries.

Methods

We performed a systematic search to identify randomized controlled trials comparing VL with DL for NTI in adults undergoing elective oromaxillofacial surgery. The primary outcome was time to intubation. Secondary outcomes included the first attempt success, overall success, incidence of nasal bleeding, Cormack and Lehane grade, and maneuvers required.

Results

Of the 456 studies identified following a systematic search, 10 were included. Meta-analysis showed a significantly lower time to tracheal intubation favoring VL (mean difference: –9.04, 95% CI [–12.71, –5.36], P < 0.001; I² = 59%). VL was also associated with a greater first attempt success (relative risk [RR]: 1.10, 95% CI [1.04, 1.16], P = 0.001). Maneuvers to facilitate intubation were less with VL (RR: 0.22, 95% CI [0.10, 0.51], P < 0.001). There was no difference in overall intubation success (RR: 1.04, 95% CI [0.98, 1.10], P = 0.17). The incidence of bleeding did not differ between the DL and VL groups (RR: 0.59, 95% CI [0.32, 1.08], P = 0.09).

Conclusions

Evidence as per this meta-analysis suggests VL leads to a shorter time to NTI, a greater first attempt success rate, and reduced need for maneuvers when compared to DL. The present study supports use of VL as a first line device for NTI in oral-maxillofacial surgeries in experienced hands.

A systematic review of meta-analyses comparing direct laryngoscopy with videolaryngoscopy

PURPOSE

In the preceding 20 years, many randomized-controlled trials and meta-analyses have compared direct Macintosh laryngoscopy with videolaryngoscopy. The videolaryngoscope blades have included both traditional Macintosh blades and hyperangulated blades. Macintosh and hyperangulated blades differ in their geometry and technique for tracheal intubation; certain patient populations may benefit from one blade type over another. The primary objective of this systematic review was to assess whether published meta-analyses comparing direct Macintosh laryngoscopy to videolaryngoscopy have accounted for the videolaryngoscope blade type. Secondary objectives evaluated heterogeneity among practitioner experience and specialty, clinical context, patient population, and original primary study outcomes.

SOURCE

A search was performed across Ovid Medline, Ovid Embase, ClinicalKey, PubMed, TRIP, AccessAnesthesiology, Google Scholar, and ANZCA discovery. A systematic review identified meta-analyses which compared direct Macintosh laryngoscopy to videolaryngoscopy. There were no patient age or clinical specialty restrictions. Exclusion criteria included non-English language, studies comparing non-Macintosh blade to videolaryngoscopy, and studies in awake patients.

PRINCIPAL FINDINGS

Twenty-one meta-analyses were identified that were published between 1 January 2000 and 7 May 2020. Macintosh and hyperangulated videolaryngoscope blades were combined in most studies (16/21; 76%). Heterogeneity was also present among practitioner experience (20/21; 95%), clinician specialty (15/21; 71%), and clinical locations (10/21; 48%). Adult and pediatric patients were combined or not defined in 5/21 studies (24%). The primary outcomes of the meta-analyses varied, with the most common (7/21; 33%) being first-pass tracheal intubation success.

CONCLUSIONS

Heterogeneity across important clinical variables is common in meta-analyses comparing direct Macintosh laryngoscopy to videolaryngoscopy. To better inform patient care, future videolaryngoscopy research should differentiate blade type, clinical context, and patient-related primary outcomes.

A randomized controlled trial comparing McGRATH series 5 videolaryngoscope with the Macintosh laryngoscope for nasotracheal intubation

Background and Aims:

The aim of this study was to compare the efficacy of McGRATH series 5 videolaryngoscope (VL) with Macintosh laryngoscope for nasotracheal intubation (NTI) in patients without anticipated difficult airways undergoing head and neck cancer surgeries.

Material and Methods:

We randomized 60 adult patients for NTI by experienced anesthetists with either Macintosh laryngoscope or McGRATH series 5 VL (VL group). The primary objective was to compare time taken for intubation (TTI). The secondary objectives included success rates, number of attempts, need for optimization maneuvers, Cormack and Lehane (CL) grade, and percentage of difficult intubations.

Results:

The mean TTI in the VL group was 43 (±10.6) versus 75 (±38.0) s in the Macintosh group (99% CI: 12.5; –51.6 s; P < 0.001). The overall intubation success rate was 100% in both groups. All 29 (100%) patients in the VL group were intubated in the first attempt versus 26 (86%) patients in the Macintosh group (99% CI –5; 33%; P = 0.11). In the Macintosh group, 20 (66%) patients needed optimization maneuver versus none in the VL group (99% CI 40; 91%; P < 0.001). In the VL group, 28 (96%) patients had a CL grade 1 view versus 9 (31%) in Macintosh group (99% CI 38; 92%; P < 0.001). There were no difficult intubations in the VL group versus 3 (10%) in the Macintosh group (99% CI: 7; 28%; P = 0.237). There was no trauma to oropharyngeal structures in either group.

Conclusion:

The McGRATH series 5 VL has faster TTI, better glottic visualization, and less need for optimization maneuvers than the Macintosh laryngoscope for NTI in patients with unanticipated difficult airways, when performed by experienced anesthetists.

Efficacy and safety of videolaryngoscopy versus direct laryngoscopy in paediatric intubation: A meta-analysis of 27 randomized controlled trials

OBJECTIVE

Anatomical and physiological differences in paediatric and adult airways make intubation of paediatric patients a challenge. This study aimed to compare the efficacy and safety of video laryngoscopy (VL) to direct laryngoscopy (DL) on intubation outcomes in paediatric patients.

DESIGN

Systematic review and meta-analysis.

SETTING

Operating room.

PATIENTS

Paediatric patients who needed tracheal intubation.

INTERVENTION

Video laryngoscopy or direct laryngoscopy.

MEASUREMENTS

Electronic searches in PubMed, Embase, and the Cochrane Library were performed to identify relevant randomized controlled trials published through January 2020. Outcomes included time to intubate, intubation failure at first attempt, Cormack-Lehane laryngeal view grade, intubation difficulty scale (IDS), percentage of glottic opening score (POGO), optimal external laryngeal manipulation (OLEM), and complications. Relative risks and weighted mean difference (WMD), with 95% CI, were employed to calculate summary results using a random-effects model.

MAIN RESULTS

Overall, 27 trials including 2461 paediatric patients were analysed. Children with video laryngoscopy intubation required longer time to intubate than direct laryngoscopy intubation (WMD 3.41, 95% CI: 1.29-5.53, P = 0.002), whereas infants receiving video laryngoscopy and direct laryngoscopy intubation experienced similar time to intubate (WMD 1.72, 95% CI: -1.09-4.54, P = 0.230). No significant differences were observed on intubation failure at first attempt between video laryngoscopy and direct laryngoscopy intubations in children and infants, respectively. Video laryngoscopy improved the POGO and intubation trauma but not Cormack-Lehane laryngeal view grade, IDS, external laryngeal manipulation, hoarseness, or oxygen desaturation.

CONCLUSIONS

Compared with direct laryngoscopy intubation, there were no benefits for paediatric patients with video laryngoscopy on time to intubate and failure at first attempt, but there were benefits with regard to POGO and intubation trauma.

Neutral Position Facilitates Nasotracheal Intubation with a GlideScope Video Laryngoscope: A Randomized Controlled Trial

The optimal head position for GlideScope facilitated nasotracheal intubation has not yet been determined. We compared the neutral and sniffing positions to establish the degree of intubation difficulty. A total of 88 ASA I-II patients requiring nasotracheal intubation for elective dental surgery with normal airways were divided into two groups according to head position, neutral position (group N), and sniffing position (group S). The primary outcome was the degree of intubation difficulty according to the Intubation Difficulty Scale (IDS): Easy (IDS = 0), mildly difficult (IDS = 1 to 4), and moderately to severely difficult (IDS ≥ 5). Eighty-seven patients completed the study and their data were analyzed. The degree of intubation difficulty was significantly different between the two groups (p = 0.004). The frequency of difficult intubation (IDS > 0) was 12 (27.9%) in group N and 28 (63.6%) in group S (difference in proportion, 35.7%; 95% confidence interval [CI], 14.8 to 52.6%; p = 0.001). The neutral position facilitates nasotracheal intubation with GlideScope by aligning the nasotracheal tube and the glottis inlet more accurately than the sniffing position.

A randomized controlled comparison of non-channeled king vision, McGrath MAC video laryngoscope and Macintosh direct laryngoscope for nasotracheal intubation in patients with predicted difficult intubations

BACKGROUND

King Vision and McGrath MAC video laryngoscopes (VLs) are increasingly used. The purpose of this study was to evaluate the performance of nasotracheal intubation in patients with predicted difficult intubations using non-channeled King Vision VL, McGrath MAC VL or Macintosh laryngoscope by experienced intubators.

METHODS

Ninety nine ASA I or II adult patients, scheduled for oral maxillofacial surgeries with El-Ganzouri risk index 1-7 were enrolled. Patients were randomly allocated to intubate with one of three laryngoscopes (non-channeled King Vision, McGrath MAC and Macintosh). The intubators were experienced with more than 100 successful nasotracheal intubations using each device. The primary outcome was intubation time. The secondary outcomes included first success rate, time required for viewing the glottis, Cormack-Lehane grade of glottis view, the number of assist maneuvers, hemodynamic responses, the subjective evaluating of sensations of performances and associated complications.

RESULTS

The intubation time of King Vision and McGrath group was comparable (37.6 ± 7.3 s vs. 35.4 ± 8.8 s) and both were shorter than Macintosh group (46.8 ± 10.4 s, p < 0.001). Both King Vision and McGrath groups had a 100% first attempt success rate, significantly higher than Macintosh group (85%, p < 0.05). The laryngoscopy time was comparable between King Vision and McGrath group (16.7 ± 5.5 s vs. 15.6 ± 6.3 s) and was shorter than Macintosh group (22.8 ± 7.2 s, p < 0.05) also. Compared with Macintosh laryngoscope, Glottis view was obviously improved when exposed with either non-channeled King Vision or McGrath MAC VL (p < 0.001), and assist maneuvers required were reduced (p < 0.001). The maximum fluctuations of MAP were significantly attenuated in VL groups (47.7 ± 12.5 mmHg and 45.1 ± 10.3 mmHg vs. 54.9 ± 10.2 mmHg, p < 0.05 and p < 0.01). Most device insertions were graded as excellent in McGrath group, followed by Macintosh and King Vision group (p = 0.0014). The tube advancements were easier in VLs compared with the Macintosh laryngoscope (p < 0.001). Sore throat was found more frequent in Macintosh group compared with King Vision group (p < 0.05).

CONCLUSIONS

Non-channeled King Vision and McGrath MAC VLs were comparable and both devices facilitated nasotracheal intubation in managing predicted difficult intubations compared with Macintosh laryngoscope.

TRIAL REGISTRATION

ClinicalTrials registration number NCT03126344 . Registered on April 24, 2017.