Direct versus Video Laryngoscopic Intubation by Novice Prehospital Intubators with and without Chest Compressions: A Pilot Manikin Study

Efficacy of Video Laryngoscopy versus Direct Laryngoscopy in the Prehospital Setting: A Systematic Review and Meta-Analysis

INTRODUCTION

Placing an endotracheal tube is a life-saving measure. Direct laryngoscopy (DL) is traditionally the default method. Video laryngoscopy (VL) has been shown to improve efficiency, but there is insufficient evidence comparing VL versus DL in the prehospital settings. This study, comprising a systematic review and random-effects meta-analysis, assesses current literature for the efficacy of VL in prehospital settings.

METHODS

PubMed and Scopus databases were searched from their beginnings through March 1, 2022 for eligible studies. Outcomes were the first successful intubation, overall success rate, and number of total DL versus VL attempts in real-life clinical situations. Cochrane's Risk of Bias (RoB) tool and the Newcastle-Ottawa Scale (NOS) were applied to assess risk of bias and study quality; Q-statistics and I2 values were used to assess heterogeneity.

RESULTS

The search yielded seven studies involving 23,953 patients, 6,674 (28%) of whom underwent intubation via VL. Compared to DL, VL was associated with a statistically higher risk ratio for first-pass success (Risk Ratio [RR] = 1.116; 95% CI, 1.005-1.239; P = .041; I2 = 87%). The I2 value for the subgroup of prospective studies was 0% compared to 89% for retrospective studies. In addition, VL was associated with higher likelihood of overall success rate (RR = 1.097; 95% CI, 1.01-1.18; P = .021; I2 = 85%) and lower mean number of attempts (Mean Difference = -0.529; 95% CI, -0.922 to -0.137; P = .008).

CONCLUSION

The meta-analysis suggested that VL was associated with higher likelihood of achieving first-pass success, greater overall success rate, and lower number of intubation attempts for adults in the prehospital settings. This study had high heterogeneity, likely presenced by the inclusion of retrospective observational studies. Further studies with more rigorous methodology are needed to confirm these results.

Tracheal Intubation during Advanced Life Support Using Direct Laryngoscopy versus Glidescope® Videolaryngoscopy by Clinicians with Limited Intubation Experience: A Systematic Review and Meta-Analysis

The use of the Glidescope® videolaryngoscope might improve tracheal intubation performance in clinicians with limited intubation experience, especially during cardiopulmonary resuscitation (CPR). The objective of this systematic review and meta-analysis is to compare direct laryngoscopy to Glidescope® videolaryngoscopy by these clinicians. PubMed/Medline and Embase were searched from their inception to 7 July 2020 for randomized controlled trials, including simulation studies. Studies on adult patients or adult-sized manikins were included when direct laryngoscopy was compared to Glidescope® videolaryngoscopy by clinicians with limited experience in tracheal intubation (<10 intubations per year). The primary outcome was the intubation first-pass success rate. Secondary outcomes were time to successful intubation and chest compression interruption duration during intubation. The risk of bias was assessed with the Cochrane risk of bias tool. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). We included 4 clinical trials with 525 patients and 20 manikin trials with 2547 intubations. Meta-analyses favored Glidescope® videolaryngoscopy over direct laryngoscopy regarding first-pass success (clinical trials: risk ratio [RR] = 1.61; 95% confidence interval [CI]: 1.16−2.23; manikin trials: RR = 1.17; 95% CI: 1.09−1.25). Clinical trials showed a shorter time to achieve successful intubation when using the Glidescope® (mean difference = 17.04 s; 95% CI: 8.51−25.57 s). Chest compression interruption duration was decreased when using the Glidescope® videolaryngoscope. The certainty of evidence ranged from very low to moderate. When clinicians with limited intubation experience have to perform tracheal intubation during advanced life support, the use of the Glidescope® videolaryngoscope improves intubation and CPR performance compared to direct laryngoscopy.

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.

Can use of video Laryngoscopes by Emergency Medical Technicians Facilitate Endotracheal Intubation during Continuous Chest Compression? A Manikin Study

Introduction

We conducted this study to evaluate the utility of two video laryngoscopes (VLs) [Pentax-AWS (AWS), GlideScope (GVL)], compared to the conventional Macintosh laryngoscope (ML), on endotracheal intubation (ETI) involving chest compressions by Level 1 Korean emergency medical technicians (EMTs) who are the equivalent of EMT-I in the United States.

Methods

This was a randomised crossover simulation study. Fifty EMTs performed endotracheal intubation in randomised sequence following two different scenarios: normal airway and difficult airway.

Results

In normal airway scenario, overall success rate did not differ between the three devices. However AWS required a shorter run-time (14.1 [10.9-19.8] seconds) to complete ETI (TC) than ML (17.7 [13.5-21.3] seconds) (p=0.017). And both VLs showed a significant superiority over ML in time required to visualise vocal cords (TVC), percentage of glottic opening (POGO) score, and incidence of dental compression (IDC). In difficult airway scenario, overall success rate of both VLs was significantly higher than ML. The TC of AWS (13.7 [11.2-16.9] seconds) and GVL (20.7 [15.1-25.9] seconds) was shorter than that of ML (24.7 [18.1-34.5] seconds) (p<0.001). The TVC of GVL was significantly shorter than that of AWS and ML. The POGO score, IDC, and ease of intubation were significantly superior with AWS, GVL, and ML, respectively.

Conclusions

Video laryngoscopes can facilitate EMT performing a faster and easier intubation without interrupting chest compressions. Moreover, AWS improves the success rate comparing to ML in difficult airway management. (Hong Kong j.emerg.med. 2014;21:308-315)

Comparison of the Pentax Airwayscope, Glidescope Video Laryngoscope, and Macintosh Laryngoscope During Chest Compression According to Bed Height

We aimed to investigate whether bed height affects intubation performance in the setting of cardiopulmonary resuscitation and which type of laryngoscope shows the best performance at each bed height.A randomized crossover manikin study was conducted. Twenty-one participants were enrolled, and they were randomly allocated to 2 groups: group A (n = 10) and group B (n = 11). The participants underwent emergency endotracheal intubation (ETI) using the Airwayscope (AWS), Glidescope video laryngoscope, and Macintosh laryngoscope in random order while chest compression was performed. Each ETI was conducted at 2 levels of bed height (minimum bed height: 68.9  cm and maximum bed height: 101.3 cm). The primary outcomes were the time to intubation (TTI) and the success rate of ETI. The P value for statistical significance was set at 0.05 and 0.017 in post-hoc test.The success rate of ETI was always 100% regardless of the type of laryngoscope or the bed height. TTI was not significantly different between the 2 bed heights regardless of the type of laryngoscope (all P > 0.05). The time for AWS was the shortest among the 3 laryngoscopes at both bed heights (13.7  ±  3.6 at the minimum bed height and 13.4  ±  4.7 at the maximum bed height) (all P < 0.017). The TTI of Glidescope video laryngoscope was not significantly shorter than that of Macintosh laryngoscope at the minimum height (17.6  ±  4.0 vs 19.6  ±  4.8; P = 0.02).The bed height, whether adjusted to the minimum or maximum setting, did not affect intubation performance. In addition, regardless of the bed height, the intubation time with the video laryngoscopes, especially AWS, was significantly shorter than that with the direct laryngoscope during chest compression.

Association Between Difficult Airway Predictors and Failed Prehosptial Endotracheal Intubation

OBJECTIVE

Difficult airway predictors (DAPs) are associated with failure of endotracheal intubation (ETI) in the emergency department (ED). The purpose of this study was to determine if DAPs are associated with failure of prehospital ETI.

METHODS

This retrospective study compared the prevalence of DAPs in cases of failed prehospital ETI successfully intubated in the ED (FPH/SED) with cases with no prehospital attempt that were successfully intubated in the ED on the first attempt by a physician using direct laryngoscopy (NPH/SED). All cases were transported by ground or air to an academic, level-1 trauma center.

RESULTS

A total of 1377 ED ETIs were performed; 161 FPH/SED and 530 NPH/SED were identified. The odds ratios with 95% confidence intervals (CIs) of finding DAPs in the FPH/SED group compared with the NPH/SED group was blood = 5.80 (95% CI, 3.89-8.63), vomit = 2.01 (95% CI, 1.25-3.21), short neck = 2.67 (95% CI, 1.39-5.03), neck immobility = 2.52 (95% CI, 1.72-3.67), airway edema = 10.52 (95% CI, 4.15-29.92), facial trauma = 4.64 (95% CI, 2.91-7.39), and large tongue = 3.08 (95% CI, 1.75-5.40). When grouped by the number of DAPs per case (0, 1, 2, 3, or ≥ 4), the odds of multiple DAPs in cases of FPH/SED compared with NPH/SED ranged from 2.89 (95% CI, 1.71-4.90) with 1 DAP to 24.55 (95% CI, 10.60-56.90) with ≥ 4 DAPs.

CONCLUSION

Cases of FPH/SED have more DAPs than NPH/SEDs.

Learning by simulation in prehospital emergency care - an integrative literature review

BACKGROUND

Acquiring knowledge and experience on high-energy trauma is often difficult due to infrequent exposure. This creates a need for training which is specifically tailored for complex prehospital conditions. Simulation provides an opportunity for ambulance nurses to focus on the actual problems in clinical practice and to develop knowledge regarding trauma care. The aim of this study was to describe what ambulance nurses and paramedics in prehospital emergency care perceive as important for learning when participating in simulation exercises.

METHODS

An integrative literature review was carried out. Criteria for inclusion were primary qualitative and quantitative studies, where research participants were ambulance nurses or paramedics, working within prehospital care settings, and where the research interventions involved simulation.

RESULTS

It was perceived important for the ambulance nurses' learning that scenarios were advanced and possible to simulate repeatedly. The repetitions contributed to increase the level of experience, which in turn improved the patients care. Moreover, realism in the simulation and being able to interact and communicate with the patient were perceived as important aspects, as was debriefing, which enabled the enhancement of knowledge and skills. The result is presented in the following categories: To gain experience, To gain practice and To be strengthened by others.

CONCLUSION

Learning through simulation does not require years of exposure to accident scenes. The simulated learning is enhanced by realistic, stressful scenarios where ambulance nurses interact with the patients. In this study, being able to communicate with the patient was highlighted as a positive contribution to learning. However, this has seldom been mentioned in a previous research on simulation. Debriefing is important for learning as it enables scrutiny of one's actions and thereby the possibility to improve and adjust one's caring. The effect of simulation exercises is important on patient outcome.

Intubation Efficiency and Perceived Ease of Use of Video Laryngoscopy vs Direct Laryngoscopy While Wearing HazMat PPE: A Preliminary High-fidelity Mannequin Study

INTRODUCTION

Management of contaminated patients in the decontamination corridor requires the use of hazardous material (HazMat) personal protective equipment (PPE). Previous studies have demonstrated that HazMat PPE may increase the difficulty of airway management. This study compared the efficiency of video laryngoscopy (VL) with traditional direct laryngoscopy (DL) during endotracheal intubation (ETI) while wearing HazMat PPE.

METHODS

Post-graduate year (PGY) 1-3 Emergency Medicine residents were randomized to VL or DL while wearing encapsulating PPE. Video laryngoscopy was performed using the GlideScope Cobalt AVL video laryngoscope. The primary outcome measure was time to successful ETI in a high-fidelity simulation mannequin. Three time points were utilized in the analysis: Time 0 (blade at lips), Time 1 (blade removed from lips after endotracheal tube placement), and Time 2 (bag valve mask [BVM] attached to endotracheal tube). Secondary outcome measures were perceived ease of use and feasibility of VL and DL ETI modalities.

RESULTS

Twenty-one of 23 (91.3%) eligible residents participated. Mean time to ETI was 10.0 seconds (SD=5.3 seconds) in the DL group and 7.8 seconds (SD=3.0 seconds) in the VL group (P=.081). Mean times from blade insertion until BVM attachment were 17.4 seconds (SD=6.0 seconds) and 15.6 seconds (SD=4.6 seconds), respectively (P=.30). There were no unsuccessful intubation attempts. Seventeen out of 20 participants (85.0%) perceived VL to be easier to use when performing ETI in PPE. Twelve out of 20 participants (60%) perceived DL to be more feasible in an actual HazMat scenario.

CONCLUSION

The time to successful ETI was not significantly different between VL and DL. Video laryngoscopy had a greater perceived ease of use, but DL was perceived to be more feasible for use in actual HazMat situations. These findings suggest that both DL and VL are reasonable modalities for use in HazMat situations, and the choice of modality could be based on the clinical situation and provider experience.

Performance of intubation with 4 different airway devices by unskilled rescuers: manikin study

INTRODUCTION

This study was designed to compare the performances of 4 airway devices in achieving successful ventilation.

METHODS

A randomized crossover trial was conducted to evaluate 4 airway devices: laryngeal mask airway (LMA), i-gel (iGEL), PENTAX Airway Scope (AWS), and Macintosh laryngoscope (MCL). Thirty-eight unskilled rescuers performed intubation on a manikin during chest compressions in normal and difficult airway scenarios. The time to ventilation, intubation success rate, and difficulty of intubation were measured.

RESULTS

The time to ventilation of the airway devices in the normal scenario had a median value of 8.8 seconds (interquartile range, 7.3-10.5 seconds) for iGEL, 16.1 seconds (13.9-19.3 seconds) for LMA, 30.6 seconds (24.6-37.6 seconds) for AWS, and 35.0 seconds (29.5-45.9 seconds) for MCL. In the difficult airway scenario, the respective time to ventilation was 8.6 seconds (7.8-10.0 seconds), 15.3 seconds (14.3-20.2 seconds), 29.4 seconds (25.7-36.3 seconds) and 59.0 seconds (46.1-103.3 seconds). The success rates were 100% and 100% for LMA, 100% and 100% for iGEL, 97.4% and 94.7% for AWS, and 78.9% and 47.4% for MCL in the normal and difficult airway scenarios. The difficulties of intubation expressed as numerical rating scale were 2.0 and 2.0 (median values) for LMA, 1.0 and 2.0 for iGEL, 3.0 and 3.0 for AWS, and 4.0 and 5.0 for MCL in the normal and difficult airway scenarios, respectively.

CONCLUSION

With novice intubators who were unfamiliar with the airway devices, the LMA, iGEL, and AWS were superior to the MCL for establishing an airway without interruption of chest compressions in a manikin study. Intubation with the iGEL was faster and easier than with the other airway devices.

Tracheal intubation of pediatric manikins during ongoing chest compressions. Does Glidescope® videolaryngoscope improve pediatric residents' performance?

Our objective was to test the ability of pediatric residents to intubate the trachea of infant and child manikins during continuous chest compressions (CC) by means of indirect videolaryngoscopy with Glidescope® versus standard direct laryngoscopy. A randomized crossover simulation trial was designed. Twenty-three residents trained to intubate child and infant manikins were eligible for the study. They were asked to perform tracheal intubation in manikins assisted by both standard laryngoscopy and Glidescope® while a colleague delivered uninterrupted chest compressions. In the infant cardiac arrest scenario, the median (IQR) total time for intubation was significantly shorter with the Miller laryngoscope [28.2 s (20.4-34.4)] than with Glidescope® [38.0 s (25.3-50.5)] (p = 0.021). The number of participants who needed more than 30 s to intubate the manikin was also significantly higher with Glidescope® (n = 13) than with the Miller laryngoscope (n = 7, p = 0.01). In the child scenario, the total time for intubation and number of intubation failures were similar with Macintosh and Glidescope® laryngoscopes. The participants' subjective difficulty of the procedure was similar for direct and videolaryngoscopy.

CONCLUSION

In simulated infant and child cardiac arrest scenarios, pediatric residents are able to intubate the trachea during CC. The videolaryngoscope Glidescope® does not improve performance in this setting.

Truview EVO2 and standard Macintosh laryngoscope for tracheal intubation during cardiopulmonary resuscitation: a comparative randomized crossover study

The aim of this study was to compare the performance of the Truview EVO2 laryngoscope in manikin-simulated cardiopulmonary resuscitation (CPR) and no-CPR scenarios with standard intubation technique. Participants performed 4 scenarios in random order: endotracheal intubation (ETI) using Macintosh laryngoscope (MCL), Truview EVO2 laryngoscope in no-CPR patient scenario, and intubation during uninterrupted chest compressions using both laryngoscopes. The participants were directed to make 3 attempts in each scenario. Primary outcomes were time to tracheal intubation (TTI) and intubation success, whereas secondary outcomes were cumulative success ratio and the number of esophageal intubation (EI). TTI and success ratios were reported per attempt. Thirty paramedics completed the study. Median TTI with Truview EVO2 with CPR was 36 (interquartile range [IQR] 29.00-52.00), 22.5 (IQR 18.33-35.00), and 18 (IQR 11.00-23.00) seconds; MCL with CPR was 23 (IQR 18.92-36.90), 16.8 (IQR 14.00-22.31), and 14.5 (IQR 11.12-16.36) seconds; Truview EVO2 without CPR was 28.6 (IQR 24.02-38.34), 21.7 (IQR 17.00-25.00), and 13 (IQR 11.90-17.79) seconds; MCL without CPR was 17 (IQR 13.23-22.29), 13 (IQR 12.09-15.26), and 12.4 (IQR 10.08-19.84) seconds for first, second, and third attempts, respectively. The P values for differences in TTI between Truview EVO2 and MCL were P < 0.0001, P = 0.0540, and P = 0.7550 in CPR scenario and P = 0.0080, P = 0.1570, and P = 0.7652 in no-CPR scenario for first, second, and third attempts, respectively. The success ratios for each of the scenarios were as follows: in CPR scenario it was 0.73 versus 0.53 (P = 0.0558), 0.83 versus 0.76 (P = 0.2633), and 1 versus 0.8 (P = 0.0058); in no-CPR scenario it was 0.63 versus 0.73 (P = 0.2068), 0.86 versus 0.86, and 0.97 versus 1 (P = 0.1637) for Truview EVO2 vs MCL in first, second, and third attempts, respectively. The cumulative success ratio related to the time of ETI was better for MCL compared with Truview EVO2 laryngoscope in both scenarios (P = 0.0029 and P = 0.0004 in no-CPR and CPR scenarios). The number of EI with MCL was 30% versus 13.3% (P = 0.0113), and for Truview EVO2 it was 20.45% versus 15.56% in CPR and no-CPR scenarios, respectively. The application of Truview EVO2 during uninterrupted chest compressions increased TTI but increased the success ratio of ETI and decreased number of EIs.

Endotracheal intubation using the Macintosh laryngoscope or KingVision video laryngoscope during uninterrupted chest compression

OBJECTIVE

Advanced airway management, endotracheal intubation (ETI), during CPR is more difficult than, for example, during anesthesia. However, new devices such as video laryngoscopes should help in such circumstances. The aim of this study was to assess the performance of the KingVision video laryngoscopes in a manikin cardiopulmonary resuscitation (CPR) scenario.

METHODS

Thirty students enrolled in the third year of paramedic school took part in the study. The simulated CPR scenario was ETI using the standard laryngoscope with a Macintosh blade (MCL) and ETI using the KingVision video laryngoscope performed during uninterrupted chest compressions. The primary endpoints were the time needed for ETI and the success ratio.

RESULTS

The mean time required for intubation was similar for both laryngoscopes: 16.6 (SD 5.11, median 15.64, range 7.9-27.9) seconds versus 17.91 (SD 5.6, median 16.28, range 10.6-28.6) seconds for the MCL and KingVision, respectively (P = 0.1888). On the first attempt at ETI, the success rate during CPR was comparable between the evaluated laryngoscopes: P = 0.9032.

CONCLUSION

The KingVision video laryngoscope proves to be less superior when used for endotracheal intubation during CPR compared to the standard laryngoscope with a Mackintosh blade. This proves true in terms of shortening the time needed for ETI and increasing the success ratio.

Cardiac arrest is a predictor of difficult tracheal intubation independent of operator experience in hospitalized patients

Background

Placement of advanced airways has been associated with worsened neurologic outcome in survivors of out-of-hospital cardiac arrest. These findings have been attributed to factors such as inexperienced operators, prolonged intubation times and other airway related complications. As an initial step to examine outcomes of advanced airway placement during in-hospital cardiac arrest (IHCA), where immediate assistance and experienced operators are continuously available, we examined whether cardiopulmonary resuscitation efforts affect intubation difficulty. Additionally, we examined whether or not the use of videolaryngoscopy increases the odds of first attempt intubation success compared with traditional direct laryngoscopy.

Methods

The study setting is a large urban university-affiliated teaching hospital where experienced airway managers are available to perform emergent intubation for any indication in any out-of-the-operating room location 24 hours a day, 7 days-a-week, 365 days-a-year. Intubations occurring in all adults >18 years-of-age who required emergent tracheal intubation outside of the operating room between January 1, 2008 and December 31, 2012 were examined retrospectively. Multivariate logistic regression was used to estimate the odds of difficult intubation during IHCA compared to other emergent non-IHCA indications with adjustment for a priori defined potential confounders (body mass index, operator experience, use of videolaryngoscopy versus direct laryngoscopy, and age).

Results

In adjusted analyses, the odds of difficult intubation were higher when taking place during IHCA (OR=2.63; 95% CI 1.1-6.3, p=0.03) compared to other emergent indications. Use of video versus direct laryngoscopy for initial intubation attempts during IHCA, however, did not improve the odds of success (adjusted OR = 0.71; 95% CI 0.35-1.43, p = 0.33).

Conclusions

Difficult intubation is more likely when intubation takes place during IHCA compared to other emergent indications, even when experienced operators are available. Under these conditions, direct laryngoscopy (versus videolaryngoscopy) remains a reasonable first choice intubation technique.

Mapping the use of simulation in prehospital care - a literature review

Background

High energy trauma is rare and, as a result, training of prehospital care providers often takes place during the real situation, with the patient as the object for the learning process. Such training could instead be carried out in the context of simulation, out of danger for both patients and personnel. The aim of this study was to provide an overview of the development and foci of research on simulation in prehospital care practice.

Methods

An integrative literature review were used. Articles based on quantitative as well as qualitative research methods were included, resulting in a comprehensive overview of existing published research. For published articles to be included in the review, the focus of the article had to be prehospital care providers, in prehospital settings. Furthermore, included articles must target interventions that were carried out in a simulation context.

Results

The volume of published research is distributed between 1984- 2012 and across the regions North America, Europe, Oceania, Asia and Middle East. The simulation methods used were manikins, films, images or paper, live actors, animals and virtual reality. The staff categories focused upon were paramedics, emergency medical technicians (EMTs), medical doctors (MDs), nurse and fire fighters. The main topics of published research on simulation with prehospital care providers included: Intubation, Trauma care, Cardiac Pulmonary Resuscitation (CPR), Ventilation and Triage.

Conclusion

Simulation were described as a positive training and education method for prehospital medical staff. It provides opportunities to train assessment, treatment and implementation of procedures and devices under realistic conditions. It is crucial that the staff are familiar with and trained on the identified topics, i.e., intubation, trauma care, CPR, ventilation and triage, which all, to a very large degree, constitute prehospital care. Simulation plays an integral role in this. The current state of prehospital care, which this review reveals, includes inadequate skills of prehospital staff regarding ventilation and CPR, on both children and adults, the lack of skills in paediatric resuscitation and the lack of knowledge in assessing and managing burns victims. These circumstances suggest critical areas for further training and research, at both local and global levels.

Comparison of success rates between two video laryngoscope systems used in a prehospital clinical trial

OBJECTIVES

The primary aims of this study were to compare paramedic success rates and complications of two different video laryngoscopes in a prehospital clinical study.

METHODS

This study was a multi-agency, prospective, non-randomized, cross over clinical trial involving paramedics from four different EMS agencies. Following completion of training sessions, six Storz CMAC™ video laryngoscopes and six King Vision™ (KV) video laryngoscopes were divided between agencies and placed into service for 6 months. Paramedics were instructed to use the video laryngoscope for all patients estimated to be ≥ 18 years old who required advanced airway management per standard operating procedure. After 6 months, the devices were crossed over for the final 6 months of the study period. Data collection was completed using a telephone data collection system with a member of the research team (available 24/7). First attempt success, overall success, and success by attempt, were compared between treatment groups using exact logistic regression adjusted for call type and user experience.

RESULTS

Over a 12-month period, 107 patients (66 CMAC, 41 KV) were treated with a study device. The CMAC had a significantly higher likelihood of first attempt success (OR = 1.85; 95% CI 0.74, 4.62; p = 0.188), overall success (OR = 7.37; 95% CI 1.73, 11.1; p = 0.002), and success by attempt (OR = 3.38; 95% CI 1.67, 6.8; p = 0.007) compared to KV. Providers reverted to direct laryngoscopy in 80% (27/34) of the video laryngoscope failure cases, with the remaining patients having their airways successfully managed with a supraglottic airway in 3 cases and bag-valve mask in 4 cases. The provider-reported complications were similar and none were statistically different between treatment groups. Complication rates were not statistically different between devices.

CONCLUSION

The CMAC had a higher likelihood of successful intubation compared to the King Vision. Complication rates were not statistically different between groups. Video laryngoscope placement success rates were not higher than our historical direct laryngoscopy success rates.

Evaluation of the Storz CMAC®, Glidescope® GVL, AirTraq®, King LTS-D™, and direct laryngoscopy in a simulated difficult airway

OBJECTIVE

The aim of this study was to compare first-attempt and overall success rates and success rates in relation to placement time among 5 different airway management devices: Storz CMAC, Glidescope GVL, AirTraq, King LTS-D, and direct laryngoscopy (DL).

METHODS

Emergency medical technician basic (EMT-B), EMT-paramedics (EMT-P), and emergency medicine residents and staff physicians placed each of the 5 devices in a random order into an AirSim (TruCorp, Belfast, UK) part-task training manikin. The difficult airway scenario was created by fixing the manikin head to a stationary object and introducing simulated emesis into the hypopharynx. First-attempt and overall success and success in relation to placement time were compared. Provider feedback about device performance was also evaluated.

RESULTS

Ninety-four providers (16 EMT-basics, 54 EMT-paramedics, and 24 emergency department doctors of medicine) consented to participation. First-attempt and overall success rates for DL, King LTS-D, GVL, and CMAC were not statistically different. Compared with DL, the AirTraq was 96% less likely to be placed successfully (odds ratio, 0.04; 95% confidence interval [CI], 0.01-0.14). When time was factored into the model, the odds of successful placement of the King LTS-D were higher compared with DL (hazard ratio [HR], 1.80; 95% CI, 1.34-2.42) and lower for GVL (HR, 0.59; 95% CI, 0.44-0.80) and AirTraq (HR, 0.228; 95% CI, 0.16-0.325). Providers ranked the CMAC first in terms of performance and preference for use in their practice setting.

CONCLUSION

Overall success rates for DL, King-LTS-D, and both video laryngoscope systems were not different. When time was factored into the model, the King LTS-D was more likely to be placed successfully.

Comparison of video laryngoscopy and direct laryngoscopy in a critical care transport service

OBJECTIVE

We evaluated video laryngoscopy (VL) (C-MAC, Karl Storz, Tuttlingen, Germany) for use in a critical care transport system. We hypothesized that the total number of airway attempts would decrease when using a video laryngoscope versus use of direct laryngoscopy (DL).

METHODS

We performed a nonrandomized group-controlled trial where six aircraft were outfitted with VL and the remainder utilized DL responding to a mix of scene runs and interfacility transports. Our primary outcome measure was the number of intubation attempts. We also compared the first-pass success (FPS) rates, laryngoscopic grades, and frequencies of rescue device use (including utilization of surgical airways) between VL and DL.

RESULTS

Crews intubated 348 patients with VL and 510 with DL. Successful endotracheal intubation within three attempts occurred 97.6% (confidence interval [CI] 96.5-98.6) of the time. The FPS rate was 85.8% (CI 83.4-88.1). In this cohort of patients, VL did not differ from DL with respect to total number of airway attempts (1.17 [CI 1.11-1.22] vs. 1.16 [CI 1.12-1.20]), FPS rate (85.6% [CI 82-89%] vs. 86.1% [CI 83-89]), or use of rescue airways (2.6% vs. 2.2%). The laryngoscopic view was superior in the VL group relative to the DL group (median Cormack-Lehane grade 1 [interquartile range (IQR) 1, 2] vs. 2 [IQR 1, 2]).

CONCLUSION

VL using the C-MAC video laryngoscope did not reduce the total number of airway attempts or improve intubation compared with DL in a system of highly trained providers.