Can the new McGrath laryngoscope rival the GlideScope Ranger portable video laryngoscope? A randomized manikin study

Purpose

We hypothesized that novices would be able to use the McGrath MAC (Aircraft Medical Ltd, Edinburgh, UK) equally as well as the GlideScope Ranger (Verathon, Inc, Bothell, WA) for intubation in regular simulated airways.

Methods

We performed a prospective, randomized crossover study of 39 medical students using the McGrath MAC, GlideScope Ranger, and Macintosh in a manikin with 2 normal airways. The primary outcome was the intubation time. Secondary outcomes included the success rates and the overall glottic view of the 3 laryngoscopes.

Results

The mean intubation times for each attempt with the McGrath MAC were 30.8 ± 16.9 seconds or less and did not differ significantly from those obtained with the GlideScope Ranger or the Macintosh in both airway scenarios (P = .18; P = .49). The mean success rates at each attempt with the McGrath MAC were 82.0% ± 38.8% or more, equal to the Macintosh and the GlideScope Ranger in both scenarios (P = .026; P = .72) except during the first intubation attempt in a normal airway (P = .008). The median grades of the glottic view visible at each intubation attempt with the McGrath Mac were Cormack-Lehane grade 1 (scenario 1: interquartile range, 1-1; scenario 2: interquartile range, 1-2), which was significantly better than the Macintosh laryngoscope in both scenarios. However, the McGrath Mac did not produce a better glottic view than the GlideScope Ranger with either scenario.

Conclusions

The intubation performance of novices using the McGrath MAC was equal to their performance using the GlideScope Ranger in regular simulated airways.     

Endotracheal intubation using the C-MAC® video laryngoscope or the Macintosh laryngoscope: A prospective, comparative study in the ICU

Introduction

Endotracheal intubation in the ICU is a challenging procedure and is frequently associated with life-threatening complications. The aim of this study was to investigate the effect of the C-MAC^® video laryngoscope on laryngeal view and intubation success compared with direct laryngoscopy.

Methods

In a single-center, prospective, comparative before-after study in an anesthetist-lead surgical ICU of a tertiary university hospital, predictors of potentially difficult tracheal intubation, number of intubation attempts, success rate and glottic view were evaluated during a 2-year study period (first year, Macintosh laryngoscopy (ML); second year, C-MAC^®).

Results

A total of 274 critically ill patients requiring endotracheal intubation were included; 113 intubations using ML and 117 intubations using the C-MAC^® were assessed. In patients with at least one predictor for difficult intubation, the C-MAC^® resulted in more successful intubations on first attempt compared with ML (34/43, 79% vs. 21/38, 55%; P = 0.03). The visualization of the glottis with ML using Cormack and Lehane (C&L) grading was more frequently rated as difficult (20%, C&L grade 3 and 4) compared with the C-MAC^® (7%, C&L grade 3 and 4) (P < 0.0001).

Conclusion

Use of the C-MAC^® video laryngoscope improved laryngeal imaging and improved the intubating success rate on the first attempt in patients with predictors for difficult intubation in the ICU setting. Video laryngoscopy seems to be a useful tool in the ICU where potentially difficult endotracheal intubations regularly occur.     

Application of dynamic laryngoscope in suggestion therapy of psychic aphonia

Background：Thecharacteristicsofthepsychicaphoniain－cludesthattheaphoniaoccurssuddenly，thepatientcan＇tspeakwithnormalsoundofcough，clearingthethroat，cryingandlaugh－ing．Indirectlaryngoscopeexaminationcouldnoabnormalityinthevocalcordwithgoodmotion．Onlypartialpatientshavepostglottaltriangularcleft．Objective：Tostudytheeffectofdynamiclaryngoscopeinsuggestiontherapyofpsychicaphonia．Unit：ZhujiangHospital，FirstMilitaryMedicalUniversity．Subjects：FromJune１９９９toJune２００１，３case…     

Tracheal intubation by novice staff: the direct vision laryngoscope or the lighted stylet (Trachlight)?

Objective: To compare the ease of use of the direct vision laryngoscope and the lighted stylet (Trachlight) by novice staff.

Methods: Ten novice medical officers (MOs) performed orotracheal intubations using either the conventional direct vision laryngoscope (DL) or a lighted stylet device (Trachlight). They performed their DL intubations during the first phase of the study, followed by the Trachlight intubations in the subsequent phase.

Results: 51 of 54 (94%) of the DL intubation attempts were successful compared with 36 of 54 (67%) of the Trachlight intubations (p<0.001). The mean (SEM) time for intubation was 44 (7) seconds in the DL group and 66 (13) seconds in the Trachlight group (p=0.004). In addition 45 of 54 (83%) of the DL intubations were successful at the first attempt versus 15 of 54 (28%) in the Trachlight group (p<0.001).

Conclusion: The results show that the use of the conventional direct vision laryngoscope in novices is associated with significantly shorter mean intubation times and higher success rates on the first attempt compared with the Trachlight.

     

Comparison of GlideScope(®) versus Macintosh laryngoscope for the removal of a hypopharyngeal foreign body: A randomized cross-over cadaver study

Objective

This study aimed to evaluate whether GlideScope^® is an effective and acceptable method for the removal of a hypopharyngeal foreign body.

Methods

This was a prospective study conducted in 28 first year emergency residents with little prior airway management experience. Participants extracted hypopharyngeal foreign bodies using a Macintosh laryngoscope and GlideScope^® with Magill and Sponge forceps. The primary endpoints were extraction time and success rate with each device. Participant preferences were also assessed.

Results

The cumulative success rate in relation to time to extraction was significantly higher with the Macintosh laryngoscope than with the GlideScope^® (p < 0.001) regardless of the extraction device. Significantly fewer attempts were required for the first successful extraction with the Macintosh laryngoscope versus GlideScope^® with Magill forceps (p = <0.001) and Sponge forceps (p = <0.001). The time for successful foreign body extraction using GlideScope^® was significantly lower when using Magill (median 46 s, IQR 28–75 s) forceps than Sponge forceps (median 79 s, IQR 41–88 s).

Conclusions

In this cadaver model, the Macintosh laryngoscope appeared to be more efficient and preferred than GlideScope^® for extracting hypopharyngeal airway foreign bodies that are associated with fatal asphyxiation.     

Comparison of the Glidescope® and Pentax AWS® laryngoscopes to the Macintosh laryngoscope for use by Advanced Paramedics in easy and simulated difficult intubation

Background

Accurate forecasting of emergency department (ED) attendances can be a valuable tool for micro and macro level planning.

Methods

Data for analysis was the counts of daily patient attendances at the ED of an acute care regional general hospital from July 2005 to Mar 2008. Patients were stratified into three acuity categories; i.e. P1, P2 and P3, with P1 being the most acute and P3 being the least acute. The autoregressive integrated moving average (ARIMA) method was separately applied to each of the three acuity categories and total patient attendances. Independent variables included in the model were public holiday (yes or no), ambient air quality measured by pollution standard index (PSI), daily ambient average temperature and daily relative humidity. The seasonal components of weekly and yearly periodicities in the time series of daily attendances were also studied. Univariate analysis by t-tests and multivariate time series analysis were carried out in SPSS version 15.

Results

By time series analyses, P1 attendances did not show any weekly or yearly periodicity and was only predicted by ambient air quality of PSI > 50. P2 and total attendances showed weekly periodicities, and were also significantly predicted by public holiday. P3 attendances were significantly correlated with day of the week, month of the year, public holiday, and ambient air quality of PSI > 50. After applying the developed models to validate the forecast, the MAPE of prediction by the models were 16.8%, 6.7%, 8.6% and 4.8% for P1, P2, P3 and total attendances, respectively. The models were able to account for most of the significant autocorrelations present in the data.

Conclusion

Time series analysis has been shown to provide a useful, readily available tool for predicting emergency department workload that can be used to plan staff roster and resource planning.     

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.