Comparison of the Airway Scope and Macintosh laryngoscope with in-line cervical stabilization by the semisolid neck collar: manikin study

Comparison of Videolaryngoscope and Intubating Laryngeal Mask Airway for Tracheal Intubation with Manual-in-line Stabilization in Patients Undergoing Cervical Spine Surgery

Background:

This prospective, randomized study compared CMAC^® videolaryngoscope with intubating laryngeal mask airway (ILMA) for intubation under manual-in-line-stabilization (MILS) in patients undergoing cervical spine surgery. Settings and Design: Sixty-five ASA Physical Status Classes I and II patients aged 18–65 years undergoing elective cervical spine surgery were randomly allocated into two groups: group CM-intubation with CMAC^® videolaryngoscope (n = 33) and Group IL-intubation using ILMA (n = 32).

Materials and Methods:

Intubation was performed in all patients after the application of MILS. The primary outcomes included first attempt and overall intubation success rate, intubation time, and apnea time. The secondary objectives were degree of head movement, hemodynamic response, incidence of desaturation, sore throat, and tissue injury.

Statistical Analysis:

Normality of data was tested by the Kolmogorov–Smirnov test. Quantitative variables were compared using the unpaired t-test or Wilcoxon Mann–Whitney test and qualitative variables were compared using the Chi-square test/Fisher's exact test. P < 0.05 was considered statistically significant.

Results:

CM group had a higher first attempt (96.97%, P = 0.054) and overall (100%, P = 0.053) intubation success rate than IL group (81.25% and 87.5%, respectively). Group CM had a significantly shorter (P < 0.0001) intubation time (33.13 ± 11.82 s) than IL group (55.71 ± 19.28 s), but group CM had significantly longer (P < 0.0001) apnea time (33.13 ± 11.82 s) than IL group (22.03 ± 7.14 s). The incidence of head movement was significantly lower in IL group (P = 0.011). Hypoxemia did not occur. Postintubation hemodynamic changes and tissue injury were significantly higher in ILMA group.

Conclusion:

CMAC group had higher intubation success rate and significantly shorter intubation time. However, ILMA group had a significantly shorter apnea time and significantly lower incidence of head movements.

First-Pass Success Intubations Using Video Laryngoscopy Versus Direct Laryngoscopy: A Retrospective Prehospital Ambulance Service Study

OBJECTIVE

In emergency medicine, endotracheal intubation is the gold standard for airway management. First-pass intubation success is beneficial because it secures the patient airway more quickly and avoids complications associated with repeated attempts, such as bleeding and swelling of soft tissue. The key to first-pass success is the ability to visualize the laryngeal inlet. Visualization can be accomplished using traditional direct laryngoscopy or video laryngoscopy. The purpose of our study was to compare the rate of successful first-pass endotracheal intubations using a video laryngoscope with that using a direct visualization laryngoscope in a prehospital emergency setting.

METHODS

We retrospectively reviewed data that had been prospectively collected in our emergency department regarding patients who underwent endotracheal intubation performed by personnel from a single local ambulance service from January 1, 2014, through December 31, 2015.

RESULTS

One hundred eighty-one patients were intubated using video laryngoscopy and 115 using direct visualization laryngoscopy. The first-pass endotracheal intubation success rate using video laryngoscopy was 12.6% higher than with direct laryngoscopy.

CONCLUSION

This retrospective study shows that video laryngoscopy had a higher first-pass success rate than direct laryngoscopy. This is promising because decreasing failure rates provide better patient outcomes.

The pressure exerted on the tongue during intubation with simultaneous cervical spine immobilisation: a comparison between four videolaryngoscopes and the Macintosh laryngoscope-a manikin study

Excessive pressures exerted on the tongue during intubation may be associated with serious complications and may make intubation more difficult. The aim of this study was to evaluate five different intubating devices in the hands of experienced anaesthetists during simulated conditions of reduced cervical spine mobility. Forty senior anaesthetists participated in the study (female = 18, male = 22). The mean pressure exerted on the tongue during intubation was recorded with a standard manometer. The overall intubation success rate as well as the difference in exerted pressures between female and male anaesthetists were also assessed. The five studied devices were used by each participant and they were randomly chosen. Each anaesthetists participating in the study had over 15 years of clinical anaesthetic practice. The mean pressure exerted on the tongue during intubation was significantly lower when the videolaryngoscopes (VLs) were used (p < 0.0001 for each of the studied VL). There were failed intubation attempts with all of the studied devices, the highest failure rate was in the Airtraq® group, 10 in 40 (25%). Female anaesthetists exerted lower pressures during intubation with all studied devices (except the Airtraq®). However, the difference was only significant for the Macintosh laryngoscope (p = 0.0083). The blades of VLs exerted lower pressures on the tongue during intubation than the Macintosh laryngoscope blade. Their use may be associated with less complications. Furthermore, male anaesthetists exerted higher pressures on the soft tissues although this was neither statistically nor clinically significant. There was higher failed intubation rate in the male anaesthetist group.

Airway Management with Cervical Spine Immobilisation: A Comparison between the Macintosh Laryngoscope, Truview Evo2, and Totaltrack VLM Used by Novices--A Manikin Study

Airway management in patients with suspected cervical spine injury plays an important role in the pathway of care of trauma patients. The aim of this study was to evaluate three different airway devices during intubation of a patient with reduced cervical spine mobility. Forty students of the third year of emergency medicine studies participated in the study (F = 26, M = 14). The time required to obtain a view of the entry to the larynx and successful ventilation time were recorded. Cormack-Lehane laryngoscopic view and damage to the incisors were also assessed. All three airway devices were used by each student (a novice) and they were randomly chosen. The mean time required to obtain the entry-to-the-larynx view was the shortest for the Macintosh laryngoscope 13.4 s (±2.14). Truview Evo2 had the shortest successful ventilation time 35.7 s (±9.27). The best view of the entry to the larynx was obtained by the Totaltrack VLM device. The Truview Evo2 and Totaltrack VLM may be an alternative to the classic Macintosh laryngoscope for intubation of trauma patients with suspected injury to the cervical spine. The use of new devices enables achieving better laryngoscopic view as well as minimising incisor damage during intubation.

Comparison of the Macintosh, McCoy, Airtraq laryngoscopes and the intubating laryngeal mask airway in a difficult airway with manual in-line stabilisation: a cross-over simulation-based study

CONTEXT

Patients with multisystem trauma undergoing intubation with manual in-line stabilisation (MILS) have a higher incidence of difficult or failed intubations.

OBJECTIVE

To compare the effectiveness of the Macintosh laryngoscope with three other intubating devices in a high fidelity simulation model.

DESIGN

Cross-over, simulation-based study.

SETTING

Tertiary referral and level 1 trauma centre between June and November 2011.

PARTICIPANTS

Thirty-five experienced airway physicians.

INTERVENTION

Each participant performed tracheal intubations on a Laerdal SimMan manikin in both a normal airway and a difficult airway scenario with MILS. The devices utilised in a randomised order were the Macintosh, McCoy, Airtraq laryngoscopes and the intubating laryngeal mask airway (iLMA).

MAIN OUTCOME MEASURES

The primary outcome was time to intubation. Success rates, grade of laryngoscopy and force of intubation were also measured.

RESULTS

One hundred and forty intubations were attempted by 35 participants in both the normal and MILS scenarios. In the normal airway, there was no difference in success rates and time to intubation. In the difficult airway with MILS, there was no difference in success rates. However, the Airtraq was associated with a longer time to intubation than the Macintosh, McCoy and iLMA, 39.3, 26.7, 23.3, 39.3, 22.8 s, respectively (P < 0.0001). The Airtraq delivered the best glottic view and lowest force of intubation in both scenarios (P < 0.0001), but was associated with the only failed intubation in the study. The McCoy was associated with a significant improvement in the glottic visualisation (P < 0.05) and reduction in the force of intubation (P <0.0001) compared with the Macintosh.

CONCLUSION

In this manikin study, the McCoy demonstrated multiple advantages over the Macintosh. The iLMA was associated with the fastest time to intubation and minimum force of insertion.

Pentax Airway Scope® vs Macintosh laryngoscope for tracheal intubation in adult patients: a systematic review and meta-analysis

The Pentax Airway Scope(®) is a single-use optical videolaryngoscope designed to assist with difficult tracheal intubation. We systematically reviewed the efficacy of the Pentax Airway Scope with that of a conventional laryngoscope for tracheal intubation in adults with 'normal' and 'difficult' airways. We included 17 randomised controlled trials with a total of 1801 participants. We used the DerSimonian and Laird random-effects model to calculate pooled relative risk or weighted mean differences. The relative risk (95% CI) of a Cormack-Lehane grade-1 laryngeal view was 2.40 (1.76-2.49) with the Pentax Airway Scope compared with the Macintosh laryngoscope, p < 0.00001. We found no other differences between the two laryngoscopes. Despite a superior laryngeal view, the Pentax Airway Scope provides little clinical benefit over the conventional laryngoscope.