Alternative intubation techniques vs Macintosh laryngoscopy in patients with cervical spine immobilization: systematic review and meta-analysis of randomized controlled trials

Comparison of BlockBuster® Laryngeal Mask Airway, King Vision® Video Laryngoscope, and flexible intubation scope for orotracheal intubation in adult patients with simulated immobilised cervical spine: A randomised controlled trial

Background and Aims

Flexible intubation scope, video laryngoscope and supraglottic airway device-guided tracheal intubation are suggested in cervical spine injury patients to avoid further exacerbation of cord injury. This study compared the intubation characteristics of BlockBuster laryngeal mask airway (BBLM), King Vision video laryngoscope (KKVL) and flexible intubation scope (FIS) in patients with simulated immobilised cervical spine.

Methods

This study was performed on 120 adult patients with American Society of Anesthesiologists physical status I-II scheduled for elective surgery under general anaesthesia requiring orotracheal intubation. Patients were randomly allocated to Group BBLM, Group KVVL and Group FIS. Time to intubation, first-attempt success rate and complications were recorded and compared between the three groups.

Results

There was a significant difference in the mean total time for intubation between the groups (P < 0.0001). The success rate of the first attempt was 75% in Group BBLM, 77% in Group KVVL and 82.5% in Group FIS (P = 0.727). Complications like mucosal damage, oesophageal intubation, and incidence of sore throat and cough were comparable in the three groups.

Conclusion

Intubation time was faster with BBLM and KVVL than with FIS in patients with simulated cervical spine immobilisation. The first-attempt success rate and complications were the same for all three devices.

Cervical spine motion during videolaryngoscopic intubation using a Macintosh-style blade with and without the anterior piece of a cervical collar: a randomized controlled trial

PURPOSE

Applying a cervical collar during videolaryngoscopic intubation can increase the lifting force required to achieve adequate glottic view, potentially increasing cervical spine motion. We aimed to compared cervical spine motion during videolaryngoscopic intubation between applying only the posterior piece (posterior-only group) and applying both the anterior and posterior pieces (anterior-posterior group) in patients wearing a cervical collar.

METHODS

We conducted a dingle-centre, parallel-group, randomized controlled trial in 102 patients (each group, N = 51). We used a videolaryngoscope (AceScope™, Ace Medical, Seoul, Republic of Korea) with a Macintosh-style blade (AceBlade™, Ace Medical, Seoul, Republic of Korea) for videolaryngoscopic intubation. In each group (posterior-only vs anterior-posterior), we measured cervical spine motion during intubation, defined as change in cervical spine angle (calculated as cervical spine angle at intubation minus that before intubation) at three cervical spine segments on lateral cervical spine radiographs.

RESULTS

The differences in mean cervical spine motion during intubation between the posterior-only and anterior-posterior groups were 1.2° (98.3% confidence interval [CI], -0.7 to 3.0), 1.0° (98.3% CI, -0.6 to 2.6), and -0.3° (98.3% CI, -2.2 to 1.7) at the occiput-C1, C1-C2, and C2-C5 segments, respectively. Mean (standard deviation) cervical spine angles at the occiput-C1, C1-C2, and C2-C5 segments in the posterior-only vs anterior-posterior groups were 10.8° (4.2) vs 9.6° (3.3) (P = 0.13), 5.6° (3.0) vs 4.7° (3.5) (P = 0.14), and 1.2° (3.7) vs 1.5° (4.3) (P = 0.74), respectively. Intubation times were shorter in the posterior-only group (median [interquartile range], 23 [19-28] sec vs 33 [20-47] sec; P = 0.003).

CONCLUSIONS

In patients wearing a cervical collar, the differences in mean cervical spine motions during intubation between applying only the posterior piece and applying both the anterior and posterior pieces were approximately 1°. Intubation times were significantly shorter without the anterior piece of a cervical collar. These findings can be referred to when removal of the anterior piece of a cervical collar is considered to address difficult videolaryngoscopic intubation conditions.

STUDY REGISTRATION

CRIS.nih.go.kr ( KCT0008151 ); first submitted 17 January 2023.

Comparison of Video Laryngoscope (VL) and Intubating Laryngeal Mask Airway (I-LMA) for Endotracheal Intubation in a Manikin with Restricted Neck Motion

Introduction

Intubating patients undergoing manual in-line stabilization (MILS) can make airway management more challenging. This study aimed to compare the outcomes of intubation with video-laryngoscope (VL) and Intubating Laryngeal Mask Airway (I-LMA) in manikin with restricted neck motion using MILS.

Methods

In this comparative study, emergency medicine residents and paramedics were randomly allocated to two crossover sets. Then the intubation outcomes (success rate, time to successful intubation, and cervical spine movement) were compared between intubation with VL and I-LMA in a manikin model with restricted cervical spine mobility, achieved through MILS.

Results

64 participants with a mean age of 28.86 ± 4.03 (range: 24-47) years and a mean duration of intubation experience of 3.63 ± 1.35 years were studied (43.75% male, 81.3% emergency medicine resident). The intubation success rate was 62 out of 64 (96.88%) in the VL method and 52 out of 64 (81.25%) in the I-LMA method (p = 0.008). The mean time to successful intubation was 33.03±16.94 seconds in the VL method and 55.03±17.34 seconds in the I-LMA method (p < 0.001). The mean cervical range of motion (CROM) in flexion-extension was 4.38±1.82 degrees in the VL method and 4.13±3.20 degrees in the I-LMA method (p = 0.158). The mean CROM in rotation was 4.27±2.62 degrees in the VL method and 4.65±2.47 degrees in the I-LMA method (p= 0.258) and the mean CROM in lateral bending was 5.35±4.45 degrees in the VL method and 7.71±6.14 degrees in the I-LMA method (p = 0.010).

Conclusion

In a manikin model with restricted cervical spine mobility, the utilization of VL significantly improved intubation success rates, reduced time to successful intubation, and limited CROM.

Airway management in patients with suspected or confirmed cervical spine injury: Guidelines from the Difficult Airway Society (DAS), Association of Anaesthetists (AoA), British Society of Orthopaedic Anaesthetists (BSOA), Intensive Care Society (ICS), Neuro Anaesthesia and Critical Care Society (NACCS), Faculty of Prehospital Care and Royal College of Emergency Medicine (RCEM)

BACKGROUND

There are concerns that airway management in patients with suspected or confirmed cervical spine injury may exacerbate an existing neurological deficit, cause a new spinal cord injury or be hazardous due to precautions to avoid neurological injury. However, there are no evidence-based guidelines for practicing clinicians to support safe and effective airway management in this setting.

METHODS

An expert multidisciplinary, multi-society working party conducted a systematic review of contemporary literature (January 2012-June 2022), followed by a three-round Delphi process to produce guidelines to improve airway management for patients with suspected or confirmed cervical spine injury.

RESULTS

We included 67 articles in the systematic review, and successfully agreed 23 recommendations. Evidence supporting recommendations was generally modest, and only one moderate and two strong recommendations were made. Overall, recommendations highlight key principles and techniques for pre-oxygenation and facemask ventilation; supraglottic airway device use; tracheal intubation; adjuncts during tracheal intubation; cricoid force and external laryngeal manipulation; emergency front-of-neck airway access; awake tracheal intubation; and cervical spine immobilisation. We also signpost to recommendations on pre-hospital care, military settings and principles in human factors.

CONCLUSIONS

It is hoped that the pragmatic approach to airway management made within these guidelines will improve the safety and efficacy of airway management in adult patients with suspected or confirmed cervical spine injury.

Structured Routine Use of Styletubation for Oro-Tracheal Intubation in Obese Patients Undergoing Bariatric Surgeries-A Case Series Report

The aim of this case series report is to provide a new topical view of styletubation (video intubating stylet technique) in obese patients undergoing bariatric surgeries. In contrast to various conventional direct laryngoscopes (DLs), videolaryngoscopes (VLs) have been applied in such obese populations with potentially difficult airway complications. The safety and effectiveness of VLs have been repeatedly studied, and the superiority of VLs has then been observed in and advocated for routine use. In this article, among our vast use experiences with styletubation (more than 54,998 patients since 2016) for first-line routine tracheal intubation, we present the unique experience to apply the styletubation technique in obese patients undergoing bariatric surgery. Consistent with the experiences applied in other patient populations, we found the styletubation technique itself to be swift (the time to intubate from 5 s to 24 s), smooth (first-attempt success rate: 100%), safe (no airway complications), and easy (high subjective satisfaction). The learning curve is steep, but competency can be enhanced if technical pitfalls can be avoided. We, therefore, propose that the styletubation technique can be feasibly and routinely applied as a first-line airway modality in obese patients undergoing bariatric surgery.

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.

Indirect laryngoscopy is more effective than direct laryngoscopy when tracheal intubation is performed by novice operators: a systematic review, meta-analysis, and trial sequential analysis

PURPOSE

We sought to perform a systematic review and meta-analysis to determine whether indirect laryngoscopy has an advantage over direct laryngoscopy in terms of the tracheal intubation rate, glottic visualization, and intubation time when used by novice operators.

METHODS

We extracted adult prospective randomized trials comparing tracheal intubation with indirect vs direct laryngoscopy in novice operators from electronic databases. We extracted the following data from the identified studies: success rate, glottic visualization, and intubation time. Data from each trial were combined via a random-effects model to calculate the pooled relative risk (RR) or weighted mean difference (WMD) with a 95% confidence interval (CI). We also performed a trial sequential analysis.

RESULTS

We included 15 articles (17 trials) comprising 2,290 patients in the systematic review. Compared with the direct laryngoscopy, indirect laryngoscopy improved success rate (RR, 1.15; 95% CI, 1.07 to 1.24; P = 0.0002; I2 = 88%), glottic visualization (RR, 1.76; 95% CI, 1.36 to 2.28; P < 0.001; I2 = 85%), and intubation time (WMD, -9.06 sec; 95% CI, -16.4 to -1.76; P = 0.01; I2 = 98%) in tracheal intubation. Trial sequential analysis showed that the total sample size was sufficient to analyze the success rate and intubation time.

CONCLUSION

In this systematic review, we found that the tracheal intubation success rate, glottic visualization, and intubation time were improved when novice operators used indirect laryngoscopy rather than direct laryngoscopy. Trial sequential analysis results indicated that the sample size was sufficient for examining the success rate and intubation time.

STUDY REGISTRATION

PROSPERO (CRD42022309045); first registered 4 September 2022.

Comparison of Indirect and Direct Laryngoscopes in Pediatric Patients with a Difficult Airway: A Systematic Review and Meta-Analysis

This meta-analysis was performed to determine whether an indirect laryngoscope is more advantageous than a direct laryngoscope for tracheal intubation in the setting of a difficult pediatric airway. Data on the intubation failure and intubation time during tracheal intubation were extracted from prospective and retrospective studies identified through a comprehensive literature search. Data from 10 individual articles (11 trials) were combined, and a DerSimonian and Laird random-effects model was used to calculate either the pooled relative risk (RR) or the weighted mean difference (WMD) and the corresponding 95% confidence interval (CI). Meta-analysis of the 10 articles indicated that the intubation failure of tracheal intubation with an indirect laryngoscope was not significantly different from that of a direct laryngoscope in patients with a difficult airway (RR 0.86, 95% CI 0.51-1.46; p = 0.59; Cochrane's Q = 50.5; I2 = 82%). Intubation time with an indirect laryngoscope was also similar to that with a direct laryngoscope (WMD 4.06 s; 95% CI -1.18-9.30; p = 0.13; Cochrane's Q 39.8; I2 = 85%). In conclusion, indirect laryngoscopes had the same intubation failure and intubation time as direct laryngoscopes in pediatric patients with a difficult airway. Currently, the benefits of indirect laryngoscopes have not been observed in the setting of a difficult pediatric airway.

Direct versus indirect epiglottis elevation in cervical spine movement during videolaryngoscopic intubation under manual in-line stabilization: a randomized controlled trial

BACKGROUND

During videolaryngoscopic intubation, direct epiglottis elevation provides a higher percentage of glottic opening score than indirect epiglottis elevation. In this randomized controlled trial, we compared cervical spine movement during videolaryngoscopic intubation under manual in-line stabilization between the two glottis exposure methods.

METHODS

Videolaryngoscopic intubation under manual in-line stabilization was performed using C-MAC® D-blade: direct (n = 51) and indirect (n = 51) epiglottis elevation groups. The percentage of glottic opening score was set equally at 50% during videolaryngoscopic intubation in both groups. The primary outcome measure was cervical spine movement during videolaryngoscopic intubation at the occiput-C1, C1-C2, and C2-C5. The secondary outcome measures included intubation performance (intubation success rate and intubation time).

RESULTS

Cervical spine movement during videolaryngoscopic intubation was significantly smaller at the occiput-C1 in the direct epiglottis elevation group than in the indirect epiglottis elevation group (mean [standard deviation] 3.9 [4.0] vs. 5.8 [3.4] °, P = 0.011), whereas it was not significantly different at the C1-C2 and C2-C5 between the two groups. All intubations were successful on the first attempt, achieving a percentage of glottic opening score of 50% in both groups. Intubation time was longer in the direct epiglottis elevation group (median [interquartile range] 29.0 [24.0-35.0] vs. 22.0 [18.0-27.0] s, P < 0.001).

CONCLUSIONS

When performing videolaryngoscopic intubation under manual in-line stabilization, direct epiglottis elevation can be more beneficial than indirect epiglottis elevation in reducing cervical spine movement during videolaryngoscopic intubation at the occiput-C1.

TRIAL REGISTRATION

Clinical Research Information Service (number: KCT0006239, date: 10/06/2021).

Comparison of Tracheal Intubation Using King Vision (Non-channeled Blade) and Tuoren Video Laryngoscopes in Patients With Cervical Spine Immobilization by Manual In-Line Stabilization: A Randomized Clinical Trial

BACKGROUND

Glottic visualization on cervical immobilization with manual in-line stabilization (MILS) might be challenging in individuals with cervical spine injuries. We compared non-channeled King Vision video laryngoscope (VL) (Ambu GmbH, Bad Nauheim, Germany) with Tuoren video laryngoscope (Henan Tuoren Medical Device, Zhengzhou, China) for endotracheal intubation in patients with cervical spine immobilization.

METHODS

A total of 124 patients undergoing elective surgery under general anesthesia were included in this study. After induction of general anesthesia, patients were randomized into two groups (62 each): group K (non-channeled blade of King Vision video laryngoscope) and group T (Tuoren video laryngoscope). Cervical spine immobilization was achieved with manual in-line stabilization. The success of the first pass intubation, the time required to intubate, glottic visualization, and intubation difficulty score (IDS) were recorded.

RESULTS

The first-attempt success rate of intubation was 95.2% (59 out of 62 patients) in group K and 90.3% (56 out of 62 patients) in group T, which were comparable. The mean glottic visualization time was significantly less with group T (12.74 ± 6.32 seconds) compared to group K (17.92 ± 4.24 seconds). Intubation time was significantly faster with group K (18.79 ± 5.857 seconds) compared to group T (27.21 ± 8.514 seconds). Both video laryngoscopes provided good grades of glottic visualization.

CONCLUSIONS

 We conclude that the performance of the Tuoren video laryngoscope is similar to the King Vision video laryngoscope in terms of first-attempt intubation success rate and glottic visualization score in patients with cervical spine immobilization by manual in-line stabilization. Although glottic visualization time was shorter with Tuoren VL, we could achieve faster intubation with King Vision VL.

Cervical spine movements during laryngoscopy and orotracheal intubation: a systematic review and meta-analysis

BACKGROUND

Airway management is challenging in trauma patients because of the fear of worsening cervical spinal cord damage. Video-integrated and optic-integrated devices and intubation laryngeal mask airways have been proposed as alternatives to direct laryngoscopy with the Macintosh laryngoscope (MAC). We performed a meta-analysis to clarify which devices cause less cervical movement during airway management.

METHODS

We searched MEDLINE, Cochrane Central, Embase and LILACS from inception to January 2022. We selected randomised controlled trials comparing alternative devices with the MAC for cervical movement from C0 to C5 in adult patients, evaluated by radiological examination. Additionally, cervical spine immobilisation (CSI) techniques were evaluated. We used the Cochrane Risk of Bias Tool to evaluate the risk of bias, and the principles of the Grading of Recommendations, Assessment, Development, and Evaluations system to assess the quality of the body of evidence.

RESULTS

Twenty-one studies (530 patients) were included. Alternative devices caused statistically significantly less cervical movement than MAC during laryngoscopy with mean differences of -3.43 (95% CI -4.93 to -1.92) at C0-C1, -3.19 (-4.04 to -2.35) at C1-C2, -1.35 (-2.19 to -0.51) at C2-C3, and -2.61 (-3.62 to -1.60) at C3-C4; and during intubation: -3.60 (-5.08 to -2.12) at C0-C1, -2.38 (-3.17 to -1.58) at C1-C2, -1.20 (-2.09 to -0.31) at C2-C3. The Airtraq and the Intubation Laryngeal Mask Airway caused statistically significant less movement than MAC restricted to some cervical segments, as well as CSI. Heterogeneity was low to moderate in most results. The quality of the body of evidence was 'low' and 'very low'.

CONCLUSIONS

Compared with the MAC, alternative devices caused less movement during laryngoscopy (C0-C4) and intubation (C0-C3). Due to the high risk of bias and the very low grade of evidence of the studies, further research is necessary to clarify the benefit of each device and to determine the efficacy of cervical immobilisation during airway management.

The Use of the Shikani Video-Assisted Intubating Stylet Technique in Patients with Restricted Neck Mobility

Among all the proposed predictors of difficult intubation defined by the intubation difficulty scale, head and neck movement (motility) stands out and plays as a crucial factor in determining the success rate and the degree of ease on endotracheal intubation. Aside from other airway tools (e.g., supraglottic airway devices), optical devices have been developed and applied for more than two decades and have shown their superiority to conventional direct laryngoscopes in many clinical scenarios and settings. Although awake/asleep flexible fiberoptic bronchoscopy is still the gold standard in patients with unstable cervical spines immobilized with a rigid cervical collar or a halo neck brace, videolaryngoscopy has been repeatedly demonstrated to be advantageous. In this brief report, for the first time, we present our clinical experience on the routine use of the Shikani video-assisted intubating stylet technique in patients with traumatic cervical spine injuries immobilized with a cervical stabilizer and in a patient with a stereotactic headframe for neurosurgery. Some trouble-shooting strategies for this technique are discussed. This paper demonstrates that the video-assisted intubating stylet technique is an acceptable alternative airway management method in patients with restricted or confined neck motility.

Cervical spine immobilization does not interfere with nasotracheal intubation performed using GlideScope videolaryngoscopy: a randomized equivalence trial

GlideScope-assisted nasotracheal intubation (NTI) has been proposed as an alternative to difficult orotracheal intubation for critical patients or those under cervical immobilization. We evaluated the difficulty of performing NTI using GlideScope under cervical orthosis. A total of 170 patients scheduled for elective cervical spinal surgery that required NTI were randomized to receive cervical immobilization using a cervical collar (collar group) or no cervical immobilization at all (control group) before anesthetic induction (group assignment at 1:1 ratio). All NTI during anesthetic induction were performed using the GlideScope. The primary outcome was time to intubation. The secondary outcomes were ease of intubation, including the necessity of auxiliary manipulations to assist intubation, and the nasotracheal intubation difficulty scale (nasoIDS). An exploratory analysis identified morphometric parameters as predictors of time to intubation, the necessity of auxiliary manipulations, and a nasoIDS score ≥ 4. For time to intubation, the mean difference (collar group-control) was - 4.19 s, with a 95% confidence interval (CI) of - 13.9 to 5.52 that lay within our defined equivalence margin of 16 s. Multivariate regressions precluded the association of cervical immobilization with a necessity for auxiliary manipulations (adjusted odds ratio [aOR] 0.53, 95% CI [0.26-1.09], P = 0.083) and a nasoIDS ≥ 4 (aOR 0.94 [0.84-1.05], P = 0.280). Among all morphometric parameters, the upper lip bite test class was predictive of a longer time to intubation (all analyses relative to class 1, 14 s longer for class 2, P = 0.032; 24 s longer for class 3, P = 0.070), increased necessity for auxiliary manipulation (aOR 2.29 [1.06-4.94], P = 0.036 for class 2; aOR 6.12 [1.04-39.94], P = 0.045 for class 3), and nasoIDS ≥ 4 (aOR 1.46 [1.14-1.89], P = 0.003 for class 3).The present study demonstrated that GlideScope achieved NTI in patients with or without cervical immobilization equivalently with respect to intubation time and ease.

Comparisons of Videolaryngoscopes for Intubation Undergoing General Anesthesia: Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The efficacy and safety of videolaryngoscopes (VLs) for tracheal intubation is still conflicting and changeable according to airway circumstances. This study aimed to compare the efficacy and safety of several VLs in patients undergoing general anesthesia.

METHODS

Medline, EMBASE, and the Cochrane Library were searched until 13 January 2020. The following VLs were evaluated compared to the Macintosh laryngoscope (MCL) by network meta-analysis for randomized controlled trials (RCTs): Airtraq, Airwayscope, C-MAC, C-MAC D-blade (CMD), GlideScope, King Vision, and McGrath. Outcome measures were the success and time (speed) of intubation, glottic view, and sore throat (safety).

RESULTS

A total of 9315 patients in 96 RCTs were included. The highest-ranked VLs for first-pass intubation success were CMD (90.6 % in all airway; 92.7% in difficult airway) and King Vision (92% in normal airway). In the rank analysis for secondary outcomes, the following VLs showed the highest efficacy or safety: Airtraq (safety), Airwayscope (speed and view), C-MAC (speed), CMD (safety), and McGrath (view). These VLs, except McGrath, were more effective or safer than MCL in moderate evidence level, whereas there was low certainty of evidence in the intercomparisons of VLs.

CONCLUSIONS

CMD and King Vision could be relatively successful than MCL and other VLs for tracheal intubation under general anesthesia. The comparisons of intubation success between VLs and MCL showed moderate certainty of evidence level, whereas the intercomparisons of VLs showed low certainty evidence.

Controversies and evidence gaps in the early management of severe traumatic brain injury: back to the ABCs

Traumatic brain injury (TBI) accounts for around 30% of all trauma-related deaths. Over the past 40 years, TBI has remained a major cause of mortality after trauma. The primary injury caused by the injurious mechanical force leads to irreversible damage to brain tissue. The potentially preventable secondary injury can be accentuated by addressing systemic insults. Early recognition and prompt intervention are integral to achieve better outcomes. Consequently, surgeons still need to be aware of the basic yet integral emergency management strategies for severe TBI (sTBI). In this narrative review, we outlined some of the controversies in the early care of sTBI that have not been settled by the publication of the Brain Trauma Foundation’s 4th edition guidelines in 2017. The topics covered included the following: mode of prehospital transport, maintaining airway patency while securing the cervical spine, achieving adequate ventilation, and optimizing circulatory physiology. We discuss fluid resuscitation and blood product transfusion as components of improving circulatory mechanics and oxygen delivery to injured brain tissue. An outline of evidence-based antiplatelet and anticoagulant reversal strategies is discussed in the review. In addition, the current evidence as well as the evidence gaps for using tranexamic acid in sTBI are briefly reviewed. A brief note on the controversial emergency surgical interventions for sTBI is included. Clinicians should be aware of the latest evidence for sTBI. Periods between different editions of guidelines can have an abundance of new literature that can influence patient care. The recent advances included in this review should be considered both for formulating future guidelines for the management of sTBI and for designing future clinical studies in domains with clinical equipoise.

Comparison of the intubation success rate between the intubating catheter and videolaryngoscope in difficult airways: a prospective randomized trial

BACKGROUND

Several devices and algorithms have already been examined and compared for difficult airway management. However, there is no existing study comparing the success of the Intubating Catheter (IC) and the Videolaryngoscope (VL) in patients who are difficult to intubate. We aimed to compare Frova IC and McGrath VL in terms of intubation success rates in patients with difficult intubation.

METHODS

This prospective, randomized study was performed in an university hospital. Patients who underwent an operation under general anesthesia and whom airway management process was deemed difficult were included in this study. Patients were randomly divided into two groups by envelopes containing a number: the intubating catheter group (Group IC), intubated using the Frova IC, and the videolaryngoscope group (Group VL), intubated using the McGrath VL. Study data were collected by a technician who was blind to the study groups and the type of device used in the intubation procedure.

RESULTS

A total of 49 patients with difficult airway were included in the study, including 25 patients in the Frova IC Group and 24 patients in the McGrath VL Group. The rate of successful intubation was determined to be 88% in Group IC and 66% in Group VL (p = 0.074). The mean duration of intubation attempt in Group VL was 44.62 seconds, whereas in Group IC, it was 51.12 seconds (p = 0.593). Group VL was found to have a significantly lower Cormack-Lehane grade compared to Group IC (p < 0.001).

CONCLUSION

Frova IC is a candidate to be an indispensable instrument in terms of cost-effectiveness in clinics such as anesthesia and emergency medicine, where difficult intubation cases are frequently encountered. However, the combination of Frova IC and McGrath VL seems to be more successful in difficult intubation situations, so future studies should focus on using these two devices together.

Split Type Postman videolaryngoscope: The newer device versus the standard Macintosh laryngoscope in simulated difficult airway – A new hope for difficult intubation scenarios

Background and Aims:

Methods:

Results:

Conclusion:

Perioperative management of spinal cord injury: the anesthesiologist's point of view

BACKGROUND

Traumatic spinal cord injury (SCI) is one of the most devastating events a person can experience. It may be life-threatening or result in long-term disability. This narrative review aims to delineate a systematic step-wise airways, breathing, circulation and disability (ABCD) approach to perioperative patient management during spinal cord surgery in order to fill some of the gaps in our current knowledge.

METHODS

We performed a comprehensive review of the literature regarding the perioperative management of traumatic spinal injuries from May 15, 2020, to December 13, 2020. We consulted the PubMed and Embase database libraries.

RESULTS

Videolaryngoscopy supplements the armamentarium available for airway management. Optical fiberscope use should be evaluated when intubating awake patients. Respiratory complications are frequent in the acute phase of traumatic spinal injury, with an estimated incidence of 36-83%. Early tracheostomy can be considered for expected difficult weaning from mechanical ventilation. Careful intraoperative management of administered fluids should be pursued to avoid complications from volume overload. Neuromonitoring requires investments in staff training and cooperation, but better outcomes have been obtained in centers where it is routinely applied. The prone position can cause rare but devastating complications, such as ischemic optic neuropathy; thus, the anesthetist should take the utmost care in positioning the patient.

CONCLUSIONS

A one-size fit all approach to spinal surgery patients is not applicable due to patient heterogeneity and the complexity of the procedures involved. The neurologic outcome of spinal surgery can be improved, and the incidence of complications reduced with better knowledge of patient-specific aspects and individualized perioperative management.

Efficacy and Safety of Video-Laryngoscopy versus Direct Laryngoscopy for Double-Lumen Endotracheal Intubation: A Systematic Review and Meta-Analysis

The available meta-analyses have inconclusively indicated the advantages of video-laryngoscopy (VL) in different clinical situations; therefore, we conducted a systematic review and meta-analysis to determine efficacy outcomes such as successful first attempt or time to perform endotracheal intubation as well as adverse events of VL vs. direct laryngoscopes (DL) for double-lumen intubation. First intubation attempt success rate was 87.9% for VL and 84.5% for DL (OR = 1.64; 95% CI: 0.95 to 2.86; I² = 61%; p = 0.08). Overall success rate was 99.8% for VL and 98.8% for DL, respectively (OR = 3.89; 95%CI: 0.95 to 15.93; I² = 0; p = 0.06). Intubation time for VL was 43.4 ± 30.4 s compared to 54.0 ± 56.3 s for DL (MD = −11.87; 95%CI: −17.06 to −6.68; I² = 99%; p < 0.001). Glottic view based on Cormack–Lehane grades 1 or 2 equaled 93.1% and 88.1% in the VL and DL groups, respectively (OR = 3.33; 95% CI: 1.18 to 9.41; I² = 63%; p = 0.02). External laryngeal manipulation was needed in 18.4% cases of VL compared with 42.8% for DL (OR = 0.28; 95% CI: 0.20 to 0.40; I² = 69%; p < 0.001). For double-lumen intubation, VL offers shorter intubation time, better glottic view based on Cormack–Lehane grade, and a lower need for ELM, but comparable first intubation attempt success rate and overall intubation success rate compared with DL.

Comparison of video-stylet and video-laryngoscope for endotracheal intubation in adults with cervical neck immobilisation: A meta-analysis of randomised controlled trials

BACKGROUND

The efficacy of video-stylet versus video-laryngoscope for tracheal intubation in patients with cervical spine immobilisation, which is known to impede the intubation process, remains unclear.

METHODS

We searched electronic databases including EMBASE, MEDLINE, Google Scholar, and Cochrane Library for randomised controlled trials comparing video-stylets with video-laryngoscopes in human subjects with cervical spine immobilisation from inception to the 25^th of January 2021. The primary outcome was the rate of successful first-attempt intubation, while secondary outcomes included overall intubation success rate, time for successful intubation, and risk of tissue damage.

RESULTS

Five trials (709 patients) published between 2009 and 2020 met the inclusion criteria. There were four types of video-stylets and three types of video-laryngoscopes examined. Hard cervical collar was applied in four studies, while manual inline stabilisation was used in one study for cervical immobilisation. There was no difference in successful first-attempt intubation rate between the video-stylet and the video-laryngoscope groups [risk ratio (RR) = 0.96, 95% CI: 0.90-1.03, p = 0.3; I² = 47%] (5 trials, 709 patients). The overall success rate (RR = 0.98, 95% CI: 0.96-1.0, p = 0.05; I² = 0%), intubation time [mean difference (MD) = 5.24, 95% CI: -8.95 to 19.43, p = 0.47; I² = 92%], and risk of tissue damage (RR = 0.87, 95% CI: 0.26-2.85, p = 0.81; I² = 39%) were also comparable between the two groups.

CONCLUSIONS

This study validates the efficacy of both video-stylets and video-laryngoscopes for tracheal intubation in the situation of cervical spine immobilisation. Further large-scale trials are warranted to support our findings in this clinical setting.

Comparing the first-attempt tracheal intubation success of the hyperangulated McGrath® X-blade vs the Macintosh-type CMAC videolaryngoscope in patients with cervical immobilization: a two-centre randomized controlled trial

We compared the hyperangulated McGrath X-blade with the Macintosh-type CMAC videolaryngoscope through the use of manual in-line stabilization on patients. The primary hypothesis was that the McGrath X-blade has a similar first-attempt success rate as the CMAC videolaryngoscope. 210 patients of ASA physical status I to III, aged 21 to 80 years old, undergoing general anesthesia requiring tracheal intubation were prospectively recruited into this two-centre randomized controlled trial, from June 2016 to April 2019. Patients with history of or predicted difficult airway, pre-existing dental risks, BMI > 35 kg/m², cervical spondylosis or myelopathy, aspiration risks, patients who declined to participate or lacked the mental capacity to give consent were excluded. Participants were intubated using either hyperangulated McGrath X-blade (MGX) or Macintosh-type CMAC (CM) videolaryngoscopy, with manual in-line stabilization. Primary outcome measured was first-attempt tracheal intubation success. Secondary outcomes included overall successful intubation within 2 attempts or 120 s, time to intubation, glottic view obtained and intubation-related complications. First-attempt success rates were 71.4% in the MGX group vs. 79.0% in the CM group (p = 0.26), with an absolute difference of -7.6% (95%CI -20%, 5.0%, p value = 0.26), but this trial was underpowered to detect a difference. Overall success was 91.4% (MGX) vs. 92.4% (CM) (p > 0.99). The Cormack & Lehane laryngeal grade was superior in the MGX group compared to CM group (Grade I: MGX 44%, CM 23%; Grade II: MGX 53%, CM 45%; Grade III: MGX 3%, CM 32%; p < 0.001). The median time to intubation using the MGX was longer than the CM [MGX 55.5 s (42.1-78.3), CM 43.8 s (38-55.3); p < 0.001]. Our study did not demonstrate a significant difference in efficacy between the McGrath X-blade and the CMAC videolaryngoscope. In patients with manual in-line stabilization, no anticipated airway difficulty and in the hands of experienced operators, the McGrath X-blade provided superior glottic views but conferred no advantage over the C-MAC, with a longer median time to intubation compared to the CMAC videolaryngoscope.Trial registration: Australian New Zealand Clinical Trial Registry (ACTRN12616000668404).

Effects of External Laryngeal Manipulation on Cervical Spine Motion during Videolaryngoscopic Intubation under Manual In-Line Stabilization: A Randomized Crossover Trial

We hypothesized that external laryngeal manipulation would reduce cervical spine motion during video laryngoscopic intubation under manual in-line stabilization by reducing the force required to lift the videolaryngoscope. In this randomized crossover trial, 27 neurointerventional patients underwent two consecutive videolaryngoscopic intubation attempts under manual in-line stabilization. External laryngeal manipulation was applied to all patients in either the first or second attempt. In the second attempt, we tried to reproduce the percentage of glottic opening score obtained in the first attempt. Primary outcomes were cervical spine motion during intubation at the occiput-C1, C1–C2, and C2–C5 segments. The intubation success rate (secondary outcome measure) was recorded. Cervical spine motion during intubation at the occiput-C1 segment was significantly smaller with than without external laryngeal manipulation (7.4° ± 4.6° vs. 11.5° ± 4.8°, mean difference −4.1° (98.33% confidence interval −5.8° to −2.3°), p < 0.001), showing a reduction of 35.7%. Cervical spine motion during intubation at the other segments was not significantly different with versus without external laryngeal manipulation. All intubations were achieved successfully regardless of the application of external laryngeal manipulation. External laryngeal manipulation is a useful method to reduce upper cervical spine motion during videolaryngoscopic intubation under manual in-line stabilization.

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.

Practice and outcomes of airway management in patients with cervical orthoses

BACKGROUND/PURPOSE

Increasing evidence indicates an association of video laryngoscopy with the success rate of airway management in patients with neck immobilization. Nevertheless, clinical practice protocols for tracheal intubation in patients immobilized using various types of cervical orthoses and the outcomes remain unclear.

METHODS

We retrospectively assessed the tracheal intubation techniques selected for patients immobilized using cervical orthoses from 2015 to 2018. The endpoints were the intubation outcomes of the different techniques and the factors associated with the selection of the technique.

RESULTS

We included 218 patients, 118 of whom wore halo vest braces (halo vest group) and 100 wore cervical collars (collar group). GlideScope video laryngoscopy (GVL) and fiberoptic bronchoscopy (FOB) were the initial intubation methods in 98 and 120 patients, respectively. GVL had a higher first-attempt success rate than did FOB in the collar group (p = 0.002) but not in the halo vest group (p = 0.522). GVL was associated with a lower risk of episodes of SaO₂< 90% (adjusted relative risk [aRR], 0.11; 95% CI, 0.02-0.67; p = 0.016) and shorter intubation time (aRR, -3.52; 95% CI, -4.79∼-2.25; p < 0.001) in the collar group. However, in the halo vest group, more frequent requirement of a rescue technique (p = 0.002) and necessity of patient awakening (p = 0.001) was noted when GVL was used. Use of the halo vest brace and noting of severe cord compression were independent predictors of the initial selection of FOB.

CONCLUSION

Caution should be exercised when using GVL for tracheal intubation in patients immobilized using halo vest braces.

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).

Comparison of Video Versus Direct Laryngoscopy: A Prospective Prehospital Air Medical Services Study

OBJECTIVE

Videolaryngoscopy (VL) in the prehospital setting remains controversial, with conflicting data on its utility. We compared C-MAC VL (Karl Storz, Tuttlingen, Germany) versus direct laryngoscopy (DL) in the prehospital setting, recording the grade of the glottic view, first pass success (FPS), overall success, and equipment functionality.

METHODS

We conducted a prospective observational study with a convenience sample of 49 adult patients who were intubated by flight crew nurses and paramedics using the C-MAC videolaryngoscope from April to November 2013. We compared Cormack-Lehane (CL) grades of view for DL and VL, intubation success rates, and equipment functionality.

RESULTS

CL grades 1 or 2 were obtained with 24 patients (49%) with DL and 45 patients (92%) with VL. Of the 25 patients (51%) who had a CL grade 3 or 4 view on DL, 22 of those patients (88%) converted to a CL grade 1 or 2 with VL (P < .001). There was an overall success rate of 96% and an FPS rate of 71%. The C-MAC videolaryngoscope was functional during intubation 100% of the time.

CONCLUSION

VL improved glottic visualization compared with DL. The FPS and overall intubation success rates were similar to other published prehospital studies using VL. The C-MAC provided reliable, high-quality video despite demanding prehospital conditions.

Randomized crossover trial comparing cervical spine motion during tracheal intubation with a Macintosh laryngoscope versus a C-MAC D-blade videolaryngoscope in a simulated immobilized cervical spine

BACKGROUND

Maintaining cervical immobilization is essential during tracheal intubation in patients with unstable cervical spines. When using the Macintosh laryngoscope for intubation in patients with cervical immobilization, substantial neck extension is required for visualization of the glottis. However, the C-MAC D-Blade videolaryngoscope may require less neck extension due to its acute angulation. We hypothesized that C-MAC D-Blade videolaryngoscopic intubation would result in less cervical spine movement than Macintosh laryngoscopic intubation. We compared the effects of C-MAC D-Blade videolaryngoscopic intubation and Macintosh laryngoscopic intubation in terms of cervical spine motion during intubation in patients with simulated cervical immobilization.

METHODS

In this randomized crossover study, the cervical spine angle was measured at the occiput-C1, C1-C2, and C2-C5 segments before and during tracheal intubation with either a C-MAC D-Blade videolaryngoscope or Macintosh laryngoscope in 20 patients, with application of a neck collar for simulated cervical immobilization. Cervical spine motion was defined as the change in angle measured before and during tracheal intubation.

RESULTS

The cervical spine motion at the occiput-C1 segment was measured at 12.1 ± 4.2° and 6.8 ± 5.0° during Macintosh laryngoscopic and C-MAC D-blade videolaryngoscopic intubation, respectively, corresponding to a 44% reduction in cervical spine motion when using the latter device (mean difference, - 5.3; 98.33% CI: - 8.8 to - 1.8; p = 0.001). However, there was no significant difference between the two intubation devices at the C1-C2 segment (- 0.6; 98.33% CI: - 3.4 to 2.2; p = 0.639) or C2-C5 segment (0.2; 98.33% CI: - 6.0 to 6.4; p = 0.929).

CONCLUSIONS

The C-MAC D-Blade videolaryngoscope causes less upper cervical spine motion than the Macintosh laryngoscope during tracheal intubation of patients with simulated cervical immobilization.

TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov on June 26, 2018 ( NCT03567902 ).

High-Risk Airway Management in the Emergency Department: Diseases and Approaches, Part II

BACKGROUND

Successful airway management is critical to the practice of emergency medicine. Thus, emergency physicians must be ready to optimize and prepare for airway management in critically ill patients with a wide range of physiologic challenges. Challenges in airway management commonly encountered in the emergency department are discussed using a pearl and pitfall discussion in this second part of a 2-part series.

OBJECTIVE

This narrative review presents an evidence-based approach to airway and patient management during endotracheal intubation in challenging cases commonly encountered in the emergency department.

DISCUSSION

Adverse events during emergent airway management are common with postintubation cardiac arrest, reported in as many as 1 in 25 intubations. Many of these adverse events can be avoided by proper identification and understanding the underlying physiology, preparation, and postintubation management. Those with high-risk features including trauma, elevated intracranial pressure, upper gastrointestinal bleed, cardiac tamponade, aortic stenosis, morbid obesity, and pregnancy must be managed with airway expertise.

CONCLUSIONS

This narrative review discusses the pearls and pitfalls of commonly encountered physiologic high-risk intubations with a focus on the emergency clinician.

Methodological tools and sensitivity analysis for assessing quality or risk of bias used in systematic reviews published in the high-impact anesthesiology journals

Background

A crucial element in the systematic review (SR) methodology is the appraisal of included primary studies, using tools for assessment of methodological quality or risk of bias (RoB). SR authors can conduct sensitivity analyses to explore whether their results are sensitive to exclusion of low quality studies or a high RoB. However, it is unknown which tools do SR authors use for assessing quality/RoB, and how they set threshold for quality/RoB in sensitivity analyses. The aim of this study was to assess quality/RoB assessment tools, the types of sensitivity analyses and quality/RoB thresholds for sensitivity analyses used within SRs published in high-impact pain/anesthesiology journals.

Methods

This was a methodological study. We analyzed SRs published from January 2005 to June 2018 in the 25% highest-ranking journals within the Journal Citation Reports (JCR) “Anesthesiology” category. We retrieved the SRs from PubMed. Two authors independently screened records, full texts, and extracted data on quality/RoB tools and sensitivity analyses. We extracted data about quality/RoB tools, types of sensitivity analyses and the thresholds for quality/RoB used in them.

Results

Out of 678 analyzed SRs, 513 (76%) reported the use of quality/RoB assessments. The most commonly reported tools for assessing quality/RoB in the studies were the Cochrane tool for risk of bias assessment (N = 251; 37%) and Jadad scale (N = 99; 15%). Meta-analysis was conducted in 451 (66%) of SRs and sensitivity analysis in 219/451 (49%). Most commonly, sensitivity analysis was conducted to explore the influence of study quality/RoB (90/219; 41%) on the results. Quality/RoB thresholds used for sensitivity analysis for those studies were clearly reported in 47 (52%) articles that used them. The quality/RoB thresholds used for sensitivity analyses were highly heterogeneous and inconsistent, even when the same tool was used.

Conclusions

A quarter of SRs reported using quality/RoB assessments, and some of them cited tools that are not meant for assessing quality/RoB. Authors who use quality/RoB to explore the robustness of their results in meta-analyses use highly heterogeneous quality/RoB thresholds in sensitivity analyses. Better methodological consistency for quality/RoB sensitivity analyses is needed.

Comparison of C-MAC D-blade videolaryngoscope and McCoy laryngoscope efficacy for nasotracheal intubation in simulated cervical spinal injury: a prospective randomized comparative study

BACKGROUND

Immobilization with cervical spine worsens endotracheal intubation condition. Though various intubation devices have been demonstrated to perform well in oral endotracheal intubation, limited information is available concerning nasotracheal intubation (NTI) in patients with cervical spine immobilization. The present study compared the performance of the C-MAC D-Blade videolaryngoscope with the McCoy laryngoscope for NTI in patients with simulated cervical spine injuries.

METHODS

This was a prospective, randomized, controlled, study done in a tertiary hospital. Ninety-five patients requiring NTI were included in data analysis: McCoy group (group M, n = 47) or C-MAC D-Blade videolaryngoscope group (group C, n = 48). A Philadelphia neck collar was applied before anesthetic induction to immobilize the cervical spine. Single experienced anesthesiologist performed NTI. The primary outcome was duration of intubation divided by three steps: nose to oropharynx; oropharynx into glottic inlet; and glottic inlet to trachea. Secondary outcomes included glottic view as percentage of glottis opening (POGO) score and Cormack-Lehance (CL) grade, modified nasal intubation-difficulty scale (NIDS) rating, hemodynamic changes before and after intubation, and complications.

RESULTS

Total intubation duration was significantly shorter in group C (39.5 ± 11.4 s) compared to group M (48.1 ± 13.9 s). Group C required significantly less time for glottic visualization and endotracheal tube placement in the trachea. More patients in group C had CL grade I and higher POGO scores (P <  0.001, for both measures). No difficulty in NTI (modified NIDS = 0) was more in group C than group M. Hemodynamic changes and incidence of complications were comparable between groups.

CONCLUSION

The C-MAC D-Blade videolaryngoscope is an effective tool for NTI in a simulated difficult airway, which improves glottic visualization and shortens intubation time relative to those with McCoy laryngoscope.

TRIAL REGISTRATION

Clinical Research Information Service of the Korea National Institute of Health, Identification number: KCT 0004535, Registered December 10, 2019, Retrospectively registered, http://cris.nih.go.kr.

French recommendations for the management of patients with spinal cord injury or at risk of spinal cord injury

OBJECTIVES

To update the French guidelines on the management of trauma patients with spinal cord injury or suspected spinal cord injury.

DESIGN

A consensus committee of 27 experts was formed. A formal conflict-of-interest (COI) policy was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised.

METHODS

The committee studied twelve questions: (1) What are the indications and arrangements for spinal immobilisation? (2) What are the arrangements for pre-hospital orotracheal intubation? (3) What are the objectives of haemodynamic resuscitation during the lesion assessment, and during the first few days in hospital? (4) What is the best way to manage these patients to improve their long-term prognosis? (5) What is the place of corticosteroid therapy in the initial phase? (6) What are the indications for magnetic resonance imaging in the lesion assessment phase? (7) What is the optimal time for surgical management? (8) What are the best arrangements for orotracheal intubation in the hospital environment? (9) What are the specific conditions for weaning these patients from mechanical ventilation for? (10) What are the procedures for analgesic treatment of these patients? (11) What are the specific arrangements for installing and mobilising these patients? (12) What is the place of early intermittent bladder sampling in these patients? Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and the evidence profiles were produced. The literature review and recommendations were made according to the GRADE® Methodology.

RESULTS

The experts' work synthesis and the application of the GRADE method resulted in 19 recommendations. Among the recommendations formalised, 2 have a high level of evidence (GRADE 1+/-) and 12 have a low level of evidence (GRADE 2+/-). For 5 recommendations, the GRADE method could not be applied, resulting in expert advice. After two rounds of scoring and one amendment, strong agreement was reached on all the recommendations.

CONCLUSIONS

There was significant agreement among experts on strong recommendations to improve practices for the management of patients with spinal cord injury.

Tracheal intubation in patients at risk for cervical spinal cord injury: A systematic review

BACKGROUND

Tracheal intubation in patients at risk for secondary spinal cord injury is potentially difficult and risky.

OBJECTIVES

To compare tracheal intubation techniques in adult patients at risk for secondary cervical spinal cord injury undergoing surgery. Primary outcome was first-attempt failure rate. Secondary outcomes were time to successful intubation and procedure complications.

DESIGN

Systematic review and meta-analysis of randomized controlled trials (RCTs) with trial sequential analysis (TSA).

DATA SOURCES

Databases searched up to July 2019.

ELIGIBILITY

Randomized controlled trials comparing different intubation techniques.

RESULTS

We included 18 trials enrolling 1972 patients. Four studies used the "awake" approach, but no study compared awake versus non-awake techniques. In remaining 14 RCTs, intubation was performed under general anesthesia. First-attempt failure rate was similar when comparing direct laryngoscopy or fiberoptic bronchoscopy versus other techniques. A better first-attempt failure rate was found with videolaryngoscopy and when pooling all the fiberoptic techniques together. All these results appeared not significant at TSA, suggesting inconclusive evidence. Intubating lighted stylet allowed faster intubation. Postoperative neurological complications were 0.34% (no significant difference among techniques). No life-threatening adverse event was reported; mild local complications were common (19.5%). The certainty of evidence was low to very low mainly due to high imprecision and indirectness.

CONCLUSIONS

Videolaryngoscopy and fiberoptic-assisted techniques might be associated with higher first-attempt failure rate over controls. However, low to very low certainty of evidence does not allow firm conclusions on the best tracheal intubation in patients at risk for cervical spinal cord injury.

Video Laryngoscopic Intubation Using the King VisionTM Laryngoscope in a Simulated Cervical Spine Trauma: A Comparison Between Non-Channeled and Channeled Disposable Blades

Videolaryngoscopes may reduce cervical spine movement during tracheal intubation in patients with neck trauma. This manikin study aimed to compare the performance of disposable non-channeled and channeled blades of the King Vision™ videolaryngoscope in simulated cervical spine injury. Fifty-eight anesthesiologists in training intubated the TruMan manikin with the neck immobilized using each blade in a randomized order. The primary outcome was the time needed for tracheal intubation, secondary aims included total success rate, the time required for visualization of the larynx, number of attempts, view of the vocal cords, and subjective assessment of both methods. Intubation time with the channeled blade was shorter, with a median time of 13 s (IQR 9-19) vs. 23 s (14.5-37.5), p < 0.001, while times to visualization of the larynx were similar in both groups (p = 0.54). Success rates were similar in both groups, but intubation with the non-channeled blade required more attempts (1.52 vs. 1.05; p < 0.001). The participants scored the intubation features of the channeled blade significantly higher, while visualization features were scored similarly in both groups. Both blades of the King Vision™ videolaryngoscope are reliable intubation devices in a simulated cervical spine injury in a manikin model when inserted by non-experienced operators. The channeled blade allowed faster intubation of the trachea.

Radiographic comparison of cervical spine motion using LMA Fastrach, LMA CTrach, and the Macintosh laryngoscope

Background/aim

The optimal technique for airway management in patients with cervical pathology remains unclear. Intubating laryngeal mask airway devices such as LMA CTrach and LMA Fastrach have not been compared for cervical spine (C-spine) movements in the context of cervical pathology. The present study aimed to determine upper C-spine movements by radiography during intubation with different devices as well as comparing the duration and success of intubation in cervical surgery.

Materials and methods

Sixty patients scheduled for elective cervical surgery were registered in this prospective, randomized study. Patients with cervical trauma/injury, previous neck surgery, and body mass index (BMI) of >35 kg/m² were excluded. Participants were randomized to one of the 3 groups: LMA CTrach, LMA Fastrach, or the Macintosh laryngoscope. C-spine motion was evaluated by measuring angles created by bordering vertebrae at cervical 1/2 and 2/3 (C1/2, C2/3) segments on 2 lateral cervical radiographs for each patient. Intubation time, ease of intubation, number of attempts, and success rate were also documented.

Results

Demographic data were similar in all the groups. The cervical movement with LMA CTrach and LMA Fastrach compared to the Macintosh laryngoscope were similar at C1/2. However, LMA CTrach significantly reduced extension compared to LMA Fastrach and Macintosh laryngoscopes at C2/3. Duration of intubation was significantly shorter with the Macintosh laryngoscope. The rate of successful intubation was 80% with LMA Fastrach and 100% with both LMA CTrach and the Macintosh laryngoscopes.

Conclusion

The LMA CTrach laryngoscopy involves less upper C-spine movement than the LMA Fastrach and does not increase the duration of the intubation period.

Cervical Spine Motion During Tracheal Intubation Using an Optiscope Versus the McGrath Videolaryngoscope in Patients With Simulated Cervical Immobilization: A Prospective Randomized Crossover Study

BACKGROUND

In patients with an unstable cervical spine, maintenance of cervical immobilization during tracheal intubation is important. In McGrath videolaryngoscopic intubation, lifting of the blade to raise the epiglottis is needed to visualize the glottis, but in patients with an unstable cervical spine, this can cause cervical spine movement. By contrast, the Optiscope, a rigid video-stylet, does not require raising of the epiglottis during tracheal intubation. We therefore hypothesized that the Optiscope would produce less cervical spine movement than the McGrath videolaryngoscope during tracheal intubation. The aim of this study was to compare the Optiscope with the McGrath videolaryngoscope with respect to cervical spine motion during intubation in patients with simulated cervical immobilization.

METHODS

The primary outcome of the study was the extent of cervical spine motion at the occiput-C1, C1-C2, and C2-C5 segments. In this randomized crossover study, the cervical spine angle was measured before and during tracheal intubation using either the Optiscope or the McGrath videolaryngoscope in 21 patients with simulated cervical immobilization. Cervical spine motion was defined as the change in angle at each cervical segment during tracheal intubation.

RESULTS

There was significantly less cervical spine motion at the occiput-C1 segment using the Optiscope rather than the McGrath videolaryngoscope (mean [98.33% CI]: 4.7° [2.4-7.0] vs 10.4° [8.1-12.7]; mean difference [98.33% CI]: -5.7° [-7.5 to -3.9]). There were also fewer cervical spinal motions at the C1-C2 and C2-C5 segments using the Optiscope (mean difference versus the McGrath videolaryngoscope [98.33% CI]: -2.4° [-3.7 to -1.2]) and -3.7° [-5.9 to -1.4], respectively).

CONCLUSIONS

The Optiscope produces less cervical spine motion than the McGrath videolaryngoscope during tracheal intubation of patients with simulated cervical immobilization.

[Study on the use of CT three-dimensional reconstruction technique for guiding tracheal intubation with rigid fiber bronchoscope in difficult airway]

OBJECTIVE

To evaluate the significance of CT three-dimensional reconstruction technique for guiding tracheal intubation with rigid fiber bronchoscope in difficult airway.

METHODS

In this study, 44 patients undergoing selective operation of ASA (American Society of Anesthesiologists physical status) I to II, neck stiffness, neck trauma needed braked, or severe cervical spondylosis were selected. The patients were randomly divided into two groups: 24 cases in the experimental group (group E) and 20 cases in the control group (group C). The stylets of the rigid fiber bronchoscopes were shaped according to the CT three-dimensional reconstruction images and parameters obtained before surgery. The rigid fiber bronchoscopes shaped according to the CT three-dimensional reconstruction images were used in group E, while the rigid fiber bronchoscopes with the original angles were used in group C. Tracheal intubation operations were all performed by an anesthesiologist who had more than 10 years' clinical experience and mastered in rigid endoscopic intubation techniques. The first attempt success rate and the total success rate of tracheal intubation, intubation time, blood pressure, heart rate and pulse oxygen saturation at different time points including pre-induction, immediately after intubation, 1-5 minutes after intubation, and intubation related complications within 24 hours were recorded.

RESULTS

The total success rate of intubation in the two groups were both 100%. The first attempt success rate of intubation was 96% in group E, and 70% in group C. The first attempt success rate of group E was higher than that of group C. The intubation time of group E was (20.7± 10.6) s, and (21.5 ± 17.6) s of group C. Group E was shorter than that of group C, but there was no significant difference (P > 0.05). RPP equaled the product of heart rate and systolic pressure, which represented the stress reaction of intubation on hemodynamics, was lower in group C at T0, T1, T2, T4 and T5 separately than that in group E, but there was no significant difference (P>0.05). There was no significant difference in tracheal intubation related complications between the two groups (P>0.05).

CONCLUSION

CT three-dimensional reconstruction technique has certain guiding significance in difficult tracheal intubation with rigid fiber bronchoscope in patients with fixed cervical spine.

Comparing the McGrath Mac Video Laryngoscope and Direct Laryngoscopy for Prehospital Emergency Intubation in Air Rescue Patients: A Multicenter, Randomized, Controlled Trial

OBJECTIVES

Tracheal intubation in prehospital emergency care is challenging. The McGrath Mac Video Laryngoscope (Medtronic, Minneapolis, MN) has been proven to be a reliable alternative for in-hospital airway management. This trial compared the McGrath Mac Video Laryngoscope and direct laryngoscopy for the prehospital setting.

DESIGN

Multicenter, prospective, randomized, controlled equivalence trial.

SETTING

Oesterreichischer Automobil- und Touring Club (OEAMTC) Helicopter Emergency Medical Service in Austria, 18-month study period.

PATIENTS

Five-hundred fourteen adult emergency patients (≥ 18 yr old).

INTERVENTIONS

Helicopter Emergency Medical Service physicians followed the institutional algorithm, comprising a maximum of two tracheal intubation attempts with each device, followed by supraglottic, then surgical airway access in case of tracheal intubation failure. No restrictions were given for tracheal intubation indication.

MEASUREMENTS MAIN RESULTS

The Primary outcome was the rate of successful tracheal intubation; equivalence range was ± 6.5% of success rates. Secondary outcomes were the number of attempts to successful tracheal intubation, time to glottis passage and first end-tidal CO2 measurement, degree of glottis visualization, and number of problems. The success rate for the two devices was equivalent: direct laryngoscopy 98.5% (254/258), McGrath Mac Video Laryngoscope 98.1% (251/256) (difference, 0.4%; 99% CI, -2.58 to 3.39). There was no statistically significant difference with regard to tracheal intubation times, number of attempts or difficulty. The view to the glottis was significantly better, but the number of technical problems was increased with the McGrath Mac Video Laryngoscope. After a failed first tracheal intubation attempt, immediate switching of the device was significantly more successful than after the second attempt (90.5% vs 57.1%; p = 0.0003), regardless of the method.

CONCLUSIONS

Both devices are equivalently well suited for use in prehospital emergency tracheal intubation of adult patients. Switching the device following a failed first tracheal intubation attempt was more successful than a second attempt with the same device.

Early Management of Acute Spinal Cord Injury-Part I: Initial Injury to Surgery

Acute spinal cord injury is a devastating event associated with substantial morbidity worldwide. The pathophysiology of spinal cord injury involves the initial mechanical trauma and the subsequent inflammatory response, which may worsen the severity of neurologic dysfunction. Interventions have been studied to reduce the extent of primary injury to the spinal cord through preventive measures and to mitigate secondary insult through early specialized care. Management, therefore, is multifold, interdisciplinary, and begins immediately at the time of injury. It includes the trauma triage, acute management of the circulatory and respiratory systems, and definitive treatment, mainly with surgical decompression and stabilization.

Videolaryngoscopy for Physician-Based, Prehospital Emergency Intubation: A Prospective, Randomized, Multicenter Comparison of Different Blade Types Using A.P. Advance, C-MAC System, and KingVision

BACKGROUND

Videolaryngoscopy is a valuable technique for endotracheal intubation. When used in the perioperative period, different videolaryngoscopes vary both in terms of technical use and intubation success rates. However, in the prehospital environment, the relative performance of different videolaryngoscopic systems is less well studied.

METHODS

We conducted this prospective, randomized, multicenter study at 4 German prehospital emergency medicine centers. One hundred sixty-eight adult patients requiring prehospital emergency intubation were treated by an emergency physician and randomized to 1 of 3 portable videolaryngoscopes (A.P. Advance, C-MAC PM, and channeled blade KingVision) with different blade types. The primary outcome variable was overall intubation success and secondary outcomes included first-attempt intubation success, glottis visualization, and difficulty with handling the devices. P values for pairwise comparisons are corrected by the Bonferroni method for 3 tests (P[BF]). All presented P values are adjusted for center.

RESULTS

Glottis visualization was comparable with all 3 devices. Overall intubation success for A.P. Advance, C-MAC, and KingVision was 96%, 97%, and 61%, respectively (overall: P < .001, A.P. Advance versus C-MAC: odds ratio [OR], 0.97, 95% confidence interval [CI], 0.13-7.42, P[BF] > 0.99; A.P. Advance versus KingVision: OR, 0.043, 95% CI, 0.0088-0.21, P[BF] < 0.001; C-MAC versus KingVision: OR, 0.043, 95% CI, 0.0088-0.21, P[BF] < 0.001). Intubation success on the first attempt with A.P. Advance, C-MAC, and KingVision was 86%, 85%, and 48%, respectively (overall: P < .001, A.P. Advance versus C-MAC: OR, 0.89, 95% CI, 0.31-2.53, P[BF] > 0.99; A.P. Advance versus KingVision: OR, 0.24, 95% CI, 0.055-0.38, P[BF] = 0.0054; C-MAC versus KingVision: OR, 0.21, 95% CI, 0.043-.34, P[BF] < 0.003). Direct laryngoscopy for successful intubation with the videolaryngoscopic device was necessary with the A.P. Advance in 5 patients, and with the C-MAC in 4 patients. In the KingVision group, 21 patients were intubated with an alternative device.

CONCLUSIONS

During prehospital emergency endotracheal intubation performed by emergency physicians, success rates of 3 commercially available videolaryngoscopes A.P. Advance, C-MAC PM, and KingVision varied markedly. We also found that although any of the videolaryngoscopes provided an adequate view, actual intubation was more difficult with the channeled blade KingVision.

Effect of Dynamic Versus Stylet-Guided Intubation on First-Attempt Success in Difficult Airways Undergoing Glidescope Laryngoscopy: A Randomized Controlled Trial

BACKGROUND

Tracheal intubation failure in patients with difficult airway is still not uncommon. While videolaryngoscopes such as the Glidescope offer better glottic vision due to an acute-angled blade, this advantage does not always lead to an increased success rate because successful insertion of the tube through the vocal cords may be the limiting factor. We hypothesize that combined use of Glidescope and fiberscope used only as a dynamic guide facilitates tracheal intubation compared to a conventional Glidescope technique with a preshaped nondynamic stylet.

METHODS

One hundred sixty adult patients with predicted difficult airway were randomly assigned to a conventional Glidescope (standard Glidescope group) or a combined Glidescope + fiberscope group intubation. In the Glidescope + fiberscope group under direct vision from the Glidescope, tracheal intubation was performed using the fiberscope as a guide without using fiberoptic vision, while in the standard Glidescope group, a conventional stylet-guided intubation technique was performed. We evaluated the rate of tracheal intubation success at first attempt as the primary end point (Fisher exact test). The difference between groups in airway injury, time to successful intubation, and the need for an alternative technique was also evaluated.

RESULTS

First-attempt intubation success was higher in the Glidescope + fiberscope group than in the standard Glidescope group (91% vs 67%; P = .0012; fragility index, 8; absolute risk reduction, 24% [95% CI, 12%-36%]). Median time to successful tracheal intubation was shorter in the Glidescope + fiberscope group (50 vs 64 seconds; P = .035). Airway injury rate was lower in the Glidescope + fiberscope group than in the standard Glidescope group (1% vs 11%; P = .035; fragility index, 1; absolute risk reduction, 10% [95% CI, 3%-18%]). Alternative rescue technique requirements to achieve tracheal intubation were higher in the standard Glidescope group (24% vs 4%; P < .001; fragility index, 7).

CONCLUSIONS

The use of a dynamic, flexible guide during a Glidescope laryngoscopy in patients with a predicted difficult airway compared to a standard intubation technique improves first-attempt intubation success, decreases the incidence of airway injury and time to successful intubation, as well as the need of an alternative technique to succeed.

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.