Tracheal intubation in patients with cervical spine immobilization: A comparison of McGrath(®) video laryngoscope and Truview EVO2(®) laryngoscope

Comparison of Intubation Conditions Between Airtraq, McGrath Video Laryngoscopes, and Macintosh Under Conditions of Simulated Trauma Airway and Rapid Sequence Induction Intubation

BACKGROUND

Patients arriving at the emergency department with a potential cervical spine injury and immobilized in a rigid cervical collar often require emergency airway management and rapid sequence induction intubation (RSII). There have been several advances in airway management with the advent of channeled (Airtraq^Ⓡ; Prodol Meditec) and nonchanneled (McGrath^Ⓡ; Meditronics) video laryngoscopes, which enable intubation without the removal of the cervical collar, but their efficacy and superiority over conventional laryngoscopy (Macintosh) in the presence of a rigid cervical collar and cricoid pressure have not been evaluated.

OBJECTIVE

Our aim was to compare the channeled (Airtraq [group A]) and nonchanneled (McGrath [Group M]) video laryngoscopes with a conventional laryngoscope (Macintosh [Group C]) in a simulated trauma airway.

METHODS

A prospective randomized controlled study was conducted in a tertiary care center. Participants were 300 patients requiring general anesthesia (American Society of Anesthesiologists class I or II), of both sexes, and aged 18-60 years. Airway management was simulated without removal of a rigid cervical collar and using cricoid pressure during intubation. After RSI, patients were intubated with one of the study techniques according to randomization. Intubation time and intubation difficulty scale (IDS) score were noted.

RESULTS

Mean intubation time was 42.2 s in group C, 35.7 s in group M, and 21.8 s in group A (p = 0.001). Intubation was easy in group M and group A (median IDS score of 0; interquartile range [IQR] 0-1 for group M and median IDS score of 1; IQR 0-2 for group A and group C; p < 0.001). A higher proportion (95.1%) of patients had an IDS score of < 1 in group A.

CONCLUSIONS

The performance of RSII with cricoid pressure in the presence of a cervical collar was easier and more rapid with channeled video laryngoscope than with other techniques.

The Use of McGrath MAC Video Laryngoscope Versus McCoy Laryngoscope in Adults with Anticipated Difficult Airway Undergoing Elective Surgery

Background

Difficult airway management remains one of the most challenging clinical situations encountered by anaesthetists.

Aim

The study compared the effectiveness of the McGrath MAC video laryngoscope to the McCoy® laryngoscope in patients with difficult airway.

Materials and Methods

Following the institution's ethical approval, the randomised controlled trial was conducted involving 74 adults with American Society of anaesthesiologists' physical status (ASA) grading of I-III scheduled for elective surgery. The Patients were randomised into either group MVL (McGrath MAC) or group MCC (McCoy) and intubated after preoxygenation with 100% oxygen and administration of IV propofol and suxamethonium. The Intubation Difficulty Score (IDS), success rate of intubation, time to intubation, number of optimising manoeuvres and complications was assessed. Statistical analysis was performed using the statistical Package for Social Sciences (SPSS) version 24.0 computer software (IBM SPSS Statistics, IBM Corp. NY, United States). Numerical and categorical data were compared using the student's t-test and Chi square (χ2) test respectively. A value of P < 0.05 was considered statistically significant.

Results

Lower IDS scores were noted in the McGrath group; 54.1% vs. 5.4% of patients had IDS score of 0 in the McGrath and McCoy groups respectively, (P < 0.001). Overall success rate was higher in the McGrath group (100% vs. 89.1%), P = 0.040.

Conclusion

Lower IDS scores and improved intubation success rate was achieved with the McGrath compared with the McCoy laryngoscope in patients with predicted difficult airway. The McGrath has proved to be useful in managing patients with difficult airway.

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:

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).

Comparative Evaluation of McGrath MAC, Truview Video Laryngoscopes and Macintosh Laryngoscope for Endotracheal Intubation in Patients Undergoing Surgery under General Anaesthesia

Background:

Videolaryngoscopy is a newly developed technique to improve tracheal intubation success. It was made to bypass the need of directly visualising the glottic inlet. These devices are advantageous as there is no need of aligning the laryngeal, pharyngeal and oral axes for a clear view, thus making intubation easier and faster.

Aim and Objectives:

Primary objective of the study was to determine the duration of laryngoscopy and intubation and Cormack - Lehane grading when intubating with McGrath MAC, Truview video laryngoscope and Macintosh laryngoscope. Secondary objectives of the study were to determine the number of attempts and optimization manouveres required to intubate.

Materials and Methods:

This study was conducted on total of 120 patients in age 20-70 years, either sex, with American Society of Anaesthesiologists physical status classes I or II scheduled for elective surgery under general anaesthesia. They were randomly assigned equally to group 1, 2 and 3 (n = 40) to be intubated by Mcgrath MAC video laryngoscope, Truview video laryngoscope and Macintosh laryngoscope respectively. Parameters recorded were duration of laryngoscopy and intubation, Cormack Lahane grading, ease of intubation, number of attempts and optimisation manouveres required for intubation.

Statistical Analysis:

Comparison of mean value among the three groups was done using student t test and percentage comparison was done using chi square test. To compare more than two variables ANOVA test was used. The P values of less than 0.05 was considered statistically significant.

Results:

Duration of laryngoscopy was significantly less in McGrath MAC group when compared to Truview group (P = 0.02) and to Macintosh group (P < 0.001) and the duration of intubation was comparable among all three study groups (P > 0.05). The difference in Cormack - Lehane grading was not significant between McGgrath MAC and Trueview (P = 0.71) but was significant between McGrath MAC and Macintosh (P = 0.002) and Trueview and Macintosh (P = 0.002). Ease of intubation was better in McGrath MAC and Truview groups compared to Macintosh group (P < 0.05). Intubation was successful in the first attempt in 39 (97.50%) patients in McGrath MAC group, 40 (100%) patients in Truview group and 35 (87.50%) patients in Macintosh group. McGrath MAC and Truview groups performed better with respect to optimization manoeuvres compared to Macintosh group (P < 0.05). Trauma was observed in 2 (5%) patients in Truview group and 5 (12.50%) patients in Macintosh group. In McGrath MAC group, no patient underwent any trauma.

Conclusion:

Although duration of laryngoscopy was significantly shorter in McGrath as compared to Truview video laryngoscope and Macintosh laryngoscope but the duration of intubation was comparable between the three groups. Both these video laryngoscopes performed significantly better than Macintosh laryngoscope with respect to laryngoscopic view, requirement of optimization manoeuvre and need for second attempt for intubation.

Comparison of Direct and Video Laryngoscopes during Different Airway Scenarios Performed by Experienced Paramedics: A Randomized Cross-Over Manikin Study

Introduction. Airway management plays an essential role in anaesthesia practice, during both elective and urgent surgery procedures and emergency medicine.

Impact of retrograde transillumination while securing the airway in obese patients undergoing bariatric surgery

Video laryngoscopy (VL) is a well-established technique used in anaesthetising obese patients who present with higher risks of airway-related difficulties and desaturations due to shorter safe apnoea periods. However, VL has certain limitations and may fail. We present the Infrared Red Intubation System (IRRIS), a new technique facilitating glottis identification in severely obese patients undergoing anaesthesia for bariatric surgery. This single-centre, prospective trial assessed the efficacy of the IRRIS for VL tracheal intubation in 20 severely obese adult patients undergoing elective bariatric surgery under general anaesthesia. We assessed the ability of the IRRIS to differentiate the transilluminated glottis from the oesophagus and laryngeal folds and evaluated the ease of intubation. The average weight in the investigated patient cohort was 145 ± 29 kg, the suprasternal tissue thickness was 12 ± 4 mm. The median IQR [range] larynx recognition time was 10 [2-50] s, which was similar to that of lean patients. The degree of obesity correlated with the duration to achieve optimal laryngoscopic view and complete the intubation procedure. We achieved successful VL insertion on the first attempt in 13 of 20 cases (65%), and on the second attempt in 7 cases (35%), emphasising the increased probability of successful intubation on the first attempt. Tracheal intubation with the IRRIS lasted 50 [IQR 20-100] s. The lowest SpO₂ during intubation was 98 [IQR 83-100] %. Addition of IRRIS to VL insertion facilitated the intubation of difficult airways in severely obese patients. IRRIS improves the visualization of the intubation pathway by selectively highlighting the airway entrance and shortens the time to successfully conclude the intubation procedure.

Laryngoscopes for difficult airway scenarios: a comparison of the available devices

INTRODUCTION

According to the American Society of Anesthesiologists, the incidence of difficult intubation in the operating room is 1.2-3.8%; however, in emergency conditions, this rate is higher and reaches even 5.3%. Successful emergency airway management is an essential component of the modern practice of medicine.

AREAS COVERED

The aim of the study is to review the literature regarding different devices used to perform endotracheal intubation (Macintosh, Miller, and McCoy laryngoscopes; ETView, GlideScope, TruView, Airtraq, McGrath MAC, Pentax AWS, Trachlight, Shikani, and Bullard) and discuss their clinical and experimental role in difficult airway management.

EXPERT COMMENTARY

Owing to the development of medical technology, there are an increasing number of videolaryngoscopes and other devices facilitating endotracheal intubation in difficult airway scenarios, including cardiopulmonary resuscitation, cervical spine injury, or face-to-face intubation. Each of these devices may bring benefits in the form of increasing the intubation effectiveness, as well as shortening the procedure, provided that the person performing intubation is familiar with the use of the device.

A comparison of direct laryngoscopy to video laryngoscopy by paramedic students in manikin-simulated airway management scenarios

INTRODUCTION

We compare the effectiveness of direct laryngoscopy (DL) to video laryngoscopy (VL) in simulated, difficult airway scenarios in a cohort of novice, prehospital, emergency care providers.

METHODS

Forty-five (45) students were randomised to DL or VL groups and then tasked to perform intubation on a manikin in three simulated airway scenarios. The scenarios included an uncomplicated intubation, intubation with manual in-line neck stabilisation (MILNS), and a simulated motor vehicle entrapment, with C-Spine held from behind, using a face-to-face intubation technique. The primary outcome was time taken to intubate, with secondary outcomes including first pass success rate, number of intubation attempts, Cormack-Lehane (CL) view grade obtained, adverse event rate, and self-reported laryngoscopist comfort.

RESULTS

Twenty-seven participants (VL n = 15, DL n = 12) completed the study. Mean time to intubate was not statistically different between VL and DL groups in any scenario. VL was associated with an increased frequency of intubation attempts (p = 0.043) and failed intubations (RR 6.4, 95% CI 0.92-44.33, p = 0.0175) in the face-to-face intubation scenario, VL was associated with a reduced incidence of poor CL view (RR 0.06, 95% CI 0.004-0.997, p = 0.0497) in the face-to-face intubation scenario, and a reduction in the frequency of dental damage (RR 0.13, 95% CI 0.02-0.96, p = 0.0165) in the supine MILNS scenario.

DISCUSSION

In our small sample, we found DL to be superior to VL in relation to a reduced risk of failed intubation and frequency of intubation attempts despite VL being superior in obtaining a good view of the vocal cords in a face-to-face intubation scenario. We found no statistically significant difference in the time taken to intubate in any scenarios. A larger study is required to inform practice and education around prehospital use of VL.

Comparison of success of tracheal intubation using Macintosh laryngoscope-assisted Bonfils fiberscope and Truview video laryngoscope in simulated difficult airway

Background and Aims:

Restriction of head and neck movements prevents the alignment of the oral, pharyngeal, and laryngeal axes and increases the incidence of difficult tracheal intubation in patients with cervical spine fractures. Video laryngoscopes have gained an important role in the management of difficult intubation, especially in situations with limited head and neck movements. This study compares the success of intubation using Macintosh laryngoscope assisted Bonfils^® fiberscope (ML-BF) with Truview^PCD video laryngoscope (TV) in patients with simulated restricted head and neck movements.

Material and Methods:

One hundred and fifty-two patients satisfying the inclusion criteria were randomly allocated to two groups of 76 each. Patients were made to lie supine on the table without a pillow and a soft collar was used to restrict head and neck movements. After a standardized premedication-induction sequence, tracheal intubation was done either with ML-BF or TV. Success of intubation, time taken for successful intubation, hemodynamic changes, airway trauma, and postoperative oropharyngeal morbidity were noted.

Results:

Intubation was successful in all the 76 patients in direct laryngoscopy-Bonfils fiberscope group and 75 out of 76 patients in TV group within the specified time (90 s). The median time taken for successful intubation with TV and ML-BF were 44 (range 26–80) s and 49 (range 28–83) s, respectively. Hemodynamic changes, airway trauma, and postoperative oropharyngeal morbidity were similar in both groups.

Conclusion:

Both TV and ML-BF are equally effective for successful tracheal intubation in patients with simulated restricted head and neck movements. In cases of difficult laryngeal visualization with routine Macintosh laryngoscope, Bonfils can be used as an adjunct to achieve successful intubation in the same laryngoscopy attempt.