Efficacy of various types of laryngoscope (direct, Pentax Airway Scope and GlideScope) for endotracheal intubation in various cervical immobilisation scenarios: a randomised cross-over simulation study

Clinically Preferred Videolaryngoscopes in Airway Management: An Updated Systematic Review

Videolaryngoscopes (VLs) have emerged as a safety net offering several advantages over direct laryngoscopy (DL). The aim of this study is to expand on our previous study conducted in 2016, to deduce which VL is most preferred by clinicians and to highlight any changes that may have occurred over the past 7 years. An extensive systematic literature review was performed on Medline, Embase, Web of Science, and Cochrane Central Database of Controlled Studies for articles published between September 2016 and January 2023. This review highlighted similar results to our study in 2016, with the CMAC being the most preferred for non-channelled laryngoscopes, closely followed by the GlideScope. For channelled videolaryngoscopes, the Pentax AWS was the most clinically preferred. This review also highlighted that there are minimal studies that compare the most-used VLs, and thus we suggest that future studies directly compare the most-used and -preferred VLs as well as the specific nature of blades to attain more useful results.

Effectiveness of intubation devices in patients with cervical spine immobilisation: a systematic review and network meta-analysis

BACKGROUND

Cervical spine immobilisation increases the difficulty of tracheal intubation. Many intubation devices have been evaluated in this setting, but their relative performance remains uncertain.

METHODS

MEDLINE, EMBASE, and the Cochrane Library were searched to identify randomised trials comparing two or more intubation devices in adults with cervical spine immobilisation. After critical appraisal, a random-effects network meta-analysis was used to pool and compare device performance. The primary outcome was the probability of first-attempt intubation success (first-pass success). For relative performance, the Macintosh direct laryngoscopy blade was chosen as the reference device.

RESULTS

We included 80 trials (8039 subjects) comparing 26 devices. Compared with the Macintosh, McGrath™ (odds ratio [OR]=11.5; 95% credible interval [CrI] 3.19-46.20), C-MAC D Blade™ (OR=7.44; 95% CrI, 1.06-52.50), Airtraq™ (OR=5.43; 95% CrI, 2.15-14.2), King Vision™ (OR=4.54; 95% CrI, 1.28-16.30), and C-MAC™ (OR=4.20; 95% CrI=1.28-15.10) had a greater probability of first-pass success. This was also true for the GlideScope™ when a tube guide was used (OR=3.54; 95% CrI, 1.05-12.50). Only the Airway Scope™ had a better probability of first-pass success compared with the Macintosh when manual-in-line stabilisation (MILS) was used as the immobilisation technique (OR=7.98; 95% CrI, 1.06-73.00).

CONCLUSIONS

For intubation performed with cervical immobilisation, seven devices had a better probability of first-pass success compared with the Macintosh. However, more studies using MILS (rather than a cervical collar or other alternative) are needed, which more accurately represent clinical practice.

CLINICAL TRIAL REGISTRATION

PROSPERO 2019 CRD42019158067 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=158067).

Success Rate of Endotracheal Intubation Using Inline Stabilization with and without Cervical Hard Collar; a Comparative Study

INTRODUCTION

Application of a rigid cervical collar may interfere with the laryngeal view, and potentially lead to failed endotracheal intubation (ETI). This study aimed to compare intubation success rates while performing inline stabilization with and without cervical hard collar.

METHODS

This randomized prospective comparative study included paramedics working in the Department of Emergency Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand to compare the success rates of endotracheal intubation on manikin using inline stabilization with and without cervical hard collar.

RESULTS

125 participants were evaluated; 63 in the rigid cervical collar and 62 in the non-cervical hard collar group. The rate of successful intubation was significantly higher using manual stabilization without cervical hard collar (61 (96.8%) vs. 55 (88.7%); p=0.048). The time required to successfully perform intubation was also shorter, with manual stabilization only (14.1 ±20.9 vs. 18.9±29.0; p = 0.081).

CONCLUSION

It seems that, removal of the rigid cervical collar during ETI in patients with suspected traumatic spine injury could increase the intubation success rate.

C-MAC Video Laryngoscope versus Conventional Direct Laryngoscopy for Endotracheal Intubation During Cardiopulmonary Resuscitation

Background and objectives: To compare the first pass success (FPS) rate of the C-MAC video laryngoscope (C-MAC) and conventional Macintosh-type direct laryngoscopy (DL) during cardiopulmonary resuscitation (CPR) in the emergency department (ED). Materials and Methods: This study was a single-center, retrospective study conducted from April 2014 to July 2018. Patients were categorized into either the C-MAC or DL group, according to the device used on the first endotracheal intubation (ETI) attempt. The primary outcome was the FPS rate. A multiple logistic regression model was developed to identify factors related to the FPS. Results: A total of 573 ETIs were performed. Of the eligible cases, 263 and 310 patients were assigned to the C-MAC and DL group, respectively. The overall FPS rate was 75% (n = 431/573). The FPS rate was higher in the C-MAC group than in the DL group, but there was no statistically significant difference (total n = 431, 79% compared to 72%, p = 0.075). In the multiple logistic regression analysis, the C-MAC use had higher FPS rate (adjusted odds ratio: 1.80; 95% CI, 1.17-2.77; p = 0.007) than that of the DL use. Conclusions: The C-MAC use on the first ETI attempt during cardiopulmonary resuscitation in the emergency department had a higher FPS rate than that of the DL use.

Comparison of the paediatric blade of the Pentax-AWS and Ovassapian airway in fibreoptic tracheal intubation in patients with limited mouth opening and cervical spine immobilization by a semi-rigid neck collar: a randomized controlled trial

Background

We compared the performances of the paediatric blade of a Pentax Airway Scope and an Ovassapian airway in fibreoptic tracheal intubation in patients whose necks were stabilized by semi-rigid neck collars.

Methods

Ninety patients were enrolled in this prospective, open-label, randomized controlled trial. Patients were randomly allocated to one of two groups (Group OVA-FOB and Group AWS-FOB). The time to tracheal intubation, success rate of tracheal intubation, number of optimization manoeuvres (jaw thrust), and difficulty of manipulation of the fibreoptic bronchoscope were compared between the groups.

Results

The time to tracheal intubation was significantly shorter (32 vs 50 s; median difference 19 s; 95% confidence interval 14-25 s; P<0.001) and manipulation of the fibreoptic bronchoscope was significantly easier for Group AWS-FOB. Optimization manoeuvres were rarely required to facilitate fibreoptic tracheal intubation in Group AWS-FOB [jaw thrust, 0 (0%); jaw thrust with anterior neck collar removal, 1 (2%)] compared with that required in Group OVA-FOB [jaw thrust, 39 (87%); jaw thrust with anterior neck collar removal, 2 (4%)]. There was no significant difference in the success rate of tracheal intubation on the first attempt between groups [Group AWS-FOB, 45 (100%); Group OVA-FOB, 44 (98%)].

Conclusions

Combined use of the paediatric blade of a Pentax Airway Scope and a fibreoptic bronchoscope enabled rapid tracheal intubation, minimizing the use of external manoeuvres of the airway, in patients with limited mouth opening and cervical spine immobilization by semi-rigid neck collars, compared with use of the Ovassapian airway and the fibreoptic bronchoscope.

Clinical trial registration

NCT02827110.

Part II: Temporomandibular Joint (TMJ)-Regeneration, Degeneration, and Adaptation

PURPOSE OF REVIEW

Elucidate temporomandibular joint (TMJ) development and pathophysiology relative to regeneration, degeneration, and adaption.

RECENT FINDINGS

The pharyngeal arch produces a highly conserved stomatognathic system that supports airway and masticatory function. An induced subperiosteal layer of fibrocartilage cushions TMJ functional and parafunctional loads. If the fibrocartilage disc is present, a fractured mandibular condyle (MC) regenerates near the eminence of the fossa via a blastema emanating from the medial periosteal surface of the ramus. TMJ degenerative joint disease (DJD) is a relatively painless osteoarthrosis, resulting in extensive sclerosis, disc destruction, and lytic lesions. Facial form and symmetry may be affected, but the residual bone is vital because distraction continues to lengthen the MC with anabolic bone modeling. Extensive TMJ adaptive, healing, and regenerative potential maintains optimal, life support functions over a lifetime. Unique aspects of TMJ development, function, and pathophysiology may be useful for innovative management of other joints.

Cervical collar makes difficult airway: a simulation study using the LEMON criteria

Objective

Endotracheal intubation is extremely difficult to perform in patients wearing a cervical collar for a head and neck injury. Therefore, we analyzed actual measurements using the look externally, evaluate 3-3-2, Mallampati score, obstruction, and neck mobility (LEMON) criteria before and after cervical collar application to investigate the causes of a difficult airway.

Methods

This simulation study was performed in 76 healthy volunteers. We measured the mouth opening, modified Mallampati classification, and neck extension before and after cervical collar application.

Results

The mean inter-incisor distance significantly decreased from 4.3 to 2.6 cm (P<0.001). Fifty-seven participants classified as I and II were newly classified as III and IV according to the modified Mallampati classification after cervical collar application (16% to 91%). The angles of neck extension significantly decreased from 44° to 22° after cervical collar application (P<0.001). Before cervical collar application, our simulations predicted that 14 of 76 participants (18%) would have a difficult airway, whereas after cervical collar application, 76 of 76 (100%) were predicted to have a difficult airway.

Conclusion

All values for the LEMON criteria (mouth opening, modified Mallampati classification, and neck extension) worsened significantly after cervical collar application. Additionally, a difficult airway was predicted in all participants after cervical collar application.