Safety and feasibility of the laryngeal tube when used by EMTs during out-of-hospital cardiac arrest

Evidence-Based Guideline for Prehospital Airway Management

Airway management is a cornerstone of emergency medical care. This project aimed to create evidence-based guidelines based on the systematic review recently conducted by the Agency for Healthcare Research and Quality (AHRQ). A technical expert panel was assembled to review the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. The panel made specific recommendations on the different PICO (population, intervention, comparison, outcome) questions reviewed in the AHRQ review and created good practice statements that summarize and operationalize these recommendations. The recommendations address the use of ventilation with bag-valve mask ventilation alone vs. supraglottic airways vs. endotracheal intubation for adults and children with cardiac arrest, medical emergencies, and trauma. Additional recommendations address the use of video laryngoscopy and drug-assisted airway management. These recommendations, and the associated good practice statements, offer EMS agencies and clinicians an opportunity to review the available evidence and incorporate it into their airway management strategies.

Prehospital Airway Management: A Systematic Review

Objective: To assess comparative benefits and harms across three airway management approaches (bag valve mask [BVM], supraglottic airway [SGA], and endotracheal intubation [ETI]) used by prehospital emergency medical services (EMS) to treat patients with trauma, cardiac arrest, or medical emergencies, and how they differ based on techniques and devices, EMS personnel and patient characteristics. Data sources: We searched electronic citation databases (Ovid® MEDLINE®, CINAHL®, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Scopus®) from 1990 to September 2020. Review methods: We followed Agency for Healthcare Research and Quality Effective Health Care Program Methods guidance. Outcomes included mortality, neurological function, return of spontaneous circulation (ROSC), and successful advanced airway insertion. Meta-analyses using profile-likelihood random effects models were conducted, with analyses stratified by study design, emergency type, and age. Results: We included 99 studies involving 630,397 patients. We found few differences in primary outcomes across airway management approaches. For survival, there was no difference for BVM versus ETI or SGA in adult and pediatric patients with cardiac arrest or trauma. For neurological function, there was no difference for BVM versus ETI and SGA versus ETI in pediatric patients with cardiac arrest. There was no difference in BVM versus ETI in adults with cardiac arrest, but improved neurological function with BVM or ETI versus SGA. There was no difference in ROSC for patients with cardiac arrest for BVM versus ETI or SGA in adults and pediatrics, or SGA versus ETI in pediatrics. There was higher frequency of ROSC in adults with SGA versus ETI. For successful advanced airway insertion, there was higher first-pass success with SGA versus ETI for all patients except adult medical patients (no difference), and no difference in overall success using SGA versus ETI in adults. Conclusions: The currently available evidence does not indicate benefits of more invasive airway approaches based on survival, neurological function, ROSC, or successful airway insertion. Strength of evidence was low or moderate; most included studies were observational. This supports the need for high-quality randomized controlled trials to advance clinical practice and EMS education and policy, and improve patient-centered outcomes.

Prehospital Airway Management Training and Education: An NAEMSP Position Statement and Resource Document

AbstractAirway management competency extends beyond technical skills to encompass a comprehensive approach to optimize patient outcomes. Initial and continuing education for airway management must therefore extend beyond a narrow focus on psychomotor skills and task completion to include appreciation of underlying pathophysiology, clinical judgment, and higher-order decision making. NAEMSP recommends:Active engagement in deliberate practice should be the guiding approach for developing and maintaining competence in airway management.EMS learners and clinicians must be educated in an escalating approach to airway management, where basic airway maneuvers form the central focus.Educational activities should extend beyond fundamental knowledge to focus on the development of clinical judgment.Optimization of patient outcomes should be valued over performance of individual airway management skills.Credentialing and continuing education activities in airway management are essential to advance clinicians beyond entry-level competency.Initial and continuing education programs should be responsive to advances in the evidence base and maintain adaptability to re-assess content and expected outcomes on a continual basis.

Prehospital Supraglottic Airways: An NAEMSP Position Statement and Resource Document

Supraglottic airway (SGA) devices provide effective conduits for oxygenation and ventilation and may offer protection from gastric aspiration. SGA devices are widely used by EMS clinicians as both rescue and primary airway management devices. While in common use for more than four decades, major developments in SGA education, science, and technology have influenced clinical strategies of SGA insertion and use in prehospital airway management for patients of all ages. NAEMSP recommends:SGAs have utility as a primary or secondary EMS airway intervention. EMS agencies should select SGA strategies that best suit available resources and local clinician skillset, as well as the nature of their clinical practice setting.EMS agencies that perform endotracheal intubation must also equip their clinicians with SGA devices and ensure adequate training and competence.In select situations, drug-assisted airway management may be used by properly credentialed EMS clinicians to facilitate SGA insertion.Confirmation of initial and continuous SGA placement using waveform capnography is strongly encouraged as a best practice.When it is functioning properly, EMS clinicians should refrain from converting an SGA to an endotracheal tube. The decision to convert an SGA to an endotracheal tube must consider the patient's condition, the effectiveness of SGA ventilations, and the clinical context and course of initial SGA insertionSGA training, competency, and clinical use must be continuously evaluated by EMS agencies using focused quality management programs.

Performance of the laryngeal tube for airway management during cardiopulmonary resuscitation

INTRODUCTION

Sudden cardiac arrest is one of the leading causes of death in Europe and the whole world. Effective chest compressions and advanced airway management have been shown to improve survival rates. Supraglottic airway devices such as the laryngeal tube (LT) are a well-known strategy for patients with cardiac arrest during both basic (BLS) and advanced life support (ALS). This systematic literature review aimed to summarize current data for using the LT when performing BLS and ALS.

EVIDENCE ACQUISITION

Recent data on the use of the LT during cardiopulmonary resuscitation (CPR) was gathered by using the Medline database and a specific search strategy. Terms were used in various order and combinations without time restrictions. A total of N.=1005 studies were identified and screened by two experienced anesthesiologists/emergency physicians independently. Altogether, data of N.=19 relevant papers were identified and included in the analysis.

EVIDENCE SYNTHESIS

Using the LT showed fast and easy placement with high success rates (76% to 94%) and was associated with higher short-term survival as compared to other strategies for initial airway management (2.2% vs. 1.4%). Quality of CPR such as chest compression fraction (CCF) before and after LT-insertion is improved (75% vs. 59%). For long-term survival, the LT showed lower survival rates.

CONCLUSIONS

Especially as initial device of airway management (for inexperienced staff), the use of a LT is easy and results in a fast insertion. The advantages of the LT as compared to bag mask ventilation and endotracheal intubation are inhomogeneous in recent literature.

Efficacy of Laryngeal Tube versus Bag Mask Ventilation by Inexperienced Providers

INTRODUCTION

Bag mask ventilation (BMV) and extraglottic devices (EGDs) are two common methods of providing rescue ventilation. BMV can be difficult to perform effectively, especially for inexperienced providers and in patients with difficult airway characteristics. There is some evidence that the laryngeal tube (LT) can be successfully placed by inexperienced providers to provide effective ventilation. However, it is unclear whether ventilation provided by LT is superior to that of BMV, especially in the hands of inexperienced airway providers. Therefore, we aimed to compare ventilation efficacy of inexperienced airway providers with BMV versus LT by primarily measuring tidal volumes and secondarily measuring peak pressures on a simulated model.

METHODS

We performed a crossover study first year emergency medicine residents and third and fourth year medical students. After a brief instructional video followed by hands on practice, participants performed both techniques in random order on a simulated model for two minutes each. Returned tidal volumes and peak pressures were measured.

RESULTS

Twenty participants were enrolled and 1200 breaths were measured, 600 per technique. The median ventilation volumes were 194 milliliters (mL) for BMV, and 387 mL for the laryngeal tube, with a median absolute difference of 170 mL (95% confidence interval [CI] 157-182 mL) (mean difference 148 mL [95% CI, 138-158 mL], p<0.001). The median ventilation peak pressures were 23 centimeters of water (cm H₂O) for BMV, and 30 cm H₂O for the laryngeal tube, with a median absolute difference of 7 cm H₂O (95% CI, 6-8 cm H2O) (mean difference 8 cm H₂O [95% CI, 7-9 cm H₂O], p<0.001).

CONCLUSION

Inexperienced airway providers were able to provide higher ventilation volumes and peak pressures with the LT when compared to BMV in a manikin model. Inexperienced providers should consider using an LT when providing rescue ventilations in obtunded or hypoventilating patients without intact airway reflexes. Further study is required to understand whether these findings are generalizable to live patients.

Prehospital Laryngeal Tube Airway Device Placement Resulting in Hypopharyngeal Perforation: A Case Report

A 26-year-old female patient presented in cardiac arrest from presumed opioid overdose. An Ambu King LTS-D laryngeal device was placed by EMS providers for airway management during the resuscitation. There was no documented difficulty with placement and breath sounds and waveform capnography were consistent with appropriate placement. The resuscitation was terminated on scene after extensive resuscitative efforts by the EMS crew. Upon autopsy of the patient, it was discovered that the laryngeal tube device had caused a deep 5 cm perforation to the left piriform recess. The laryngeal tube had bent and was pushed into the perforation in the piriform recess; had the patient had regain of spontaneous circulation this could have caused significant morbidity. Laryngeal tube airway devices have shown increased usage in healthcare settings, in particular in the prehospital arena. Studies of these airway devices have shown they have quick insertion times, high success rates, and low complications. Tongue swelling and minor trauma are common complications of laryngeal tube airway devices. The case report describes a rare, yet potentially life-threatening, complication of laryngeal tube airway device placement- hypopharyngeal injury. If unrecognized, this injury could lead to serious complications. Providers should be aware of the common and uncommon injuries that are associated with prehospital laryngeal tube airway device placement.

Comparing the efficacy of bag-valve mask, endotracheal intubation, and laryngeal mask airway for subjects with out-of-hospital cardiac arrest: an indirect meta-analysis

Background

For subjects with out-of-hospital cardiac arrest (OHCA), bag-valve mask (BVM), endotracheal intubation (ETI), and laryngeal mask airway (LMA) are the most common methods of ventilatory support; however, the best choice remains controversial.

Methods

A comprehensive search of online databases was performed. A traditional meta-analysis was performed to determine the risk ratio of BVM vs. LMA and ETI vs. LMA. Indirect treatment comparisons (ITCs) were conducted to compare BVM and ETI.

Results

A total of 13 full-text articles reporting the efficacy of BVM, ETI, and LMA were considered in this analysis. BVM and LMA had the same effect regarding return of spontaneous circulation (ROSC) (23% vs. 24%; RR =0.84), survival rate at admission (19% vs. 21%; RR =0.82) or discharge (6% vs. 4%; RR =0.61). ETI was superior to LMA in terms of ROSC (48% vs. 23%; RR =0.72) and survival rate at both admission (27% vs. 19%; RR =0.85) and discharge (12% vs. 4%; RR =0.90). BVM was inferior to ETI in terms of ROSC (24% vs. 48%; RR =0.86), survival to admission rate (21% vs. 27%; RR =1.037), and survival to discharge rate (6% vs. 12%; RR =1.476).

Conclusions

ETI should be considered for airway management as early as possible, which can improve the subject's success rate of recovery and survival to admission rate. In future, large-scale, multi-center, randomized controlled studies should be conducted to evaluate the exact efficacy of BVM, ETI, and LMA for the first aid of subjects with OHCA.

Advanced airway management during adult cardiac arrest: A systematic review

AIM

To systematically review the literature on advanced airway management during adult cardiac arrest in order to inform the International Liaison Committee of Resuscitation (ILCOR) consensus on science and treatment recommendations.

METHODS

The review was performed according to PRISMA guidelines and registered on PROSPERO (CRD42018115556). We searched Medline, Embase, and Evidence-Based Medicine Reviews for controlled trials and observational studies published before October 30, 2018. The population included adult patients with cardiac arrest. Two investigators reviewed studies for relevance, extracted data, and assessed the risk of bias of individual studies.

RESULTS

We included 78 observational studies and 11 controlled trials. Most of the observational studies and all of the controlled trials only included patients with out-of-hospital cardiac arrest. The risk of bias for individual observational studies was overall assessed as critical or serious, with confounding and selection bias being the primary sources of bias. Three of the controlled trials, all published in 2018, were powered for clinical outcomes with two comparing a supraglottic airway to tracheal intubation and one comparing bag-mask ventilation to tracheal intubation. All three trials had some concerns regarding risk of bias primarily due to lack of blinding and variable adherence to the protocol. Clinical and methodological heterogeneity across studies, for both the observational studies and the controlled trials, precluded any meaningful meta-analyses.

CONCLUSIONS

We identified a large number of studies related to advanced airway management in adult cardiac arrest. Three recently published, large randomized trials in out-of-hospital cardiac arrest will help to inform future guidelines. Trials of advanced airway management during in-hospital cardiac arrest are lacking.

Emergency Department Management of Out-of-Hospital Laryngeal Tubes

STUDY OBJECTIVE

Laryngeal tubes are commonly used by emergency medical services (EMS) personnel for out-of-hospital advanced airway management. The emergency department (ED) management of EMS-placed laryngeal tubes is unknown. We seek to describe ED airway management techniques, success, and complications of patients receiving EMS laryngeal tubes.

METHODS

Using a keyword text search of ED notes, we identified patients who arrived at our ED with a laryngeal tube from 2010 through 2017. We performed structured chart and video reviews for all eligible patients. In our ED, emergency physicians perform all airway management, and there is no protocol dictating airway management for patients arriving with a laryngeal tube. Using descriptive methods, we report the techniques, success, and complications of ED airway management.

RESULTS

We analyzed data on 647 patients receiving out-of-hospital laryngeal tubes, including 472 (73%) with cardiac arrest from medical causes, 75 (21%) with cardiac arrest from trauma, and 100 (15%) with other conditions. For 580 patients (89%), emergency physicians exchanged the laryngeal tube for a definitive airway in the ED. Of the 67 patients not intubated in the ED, 66 died in the ED without further airway management. Of the 580 patients intubated in the ED, orotracheal intubation was the first method attempted for 578 (>99%) and was successful on the first attempt for 515 of 578 (89%). Macintosh video laryngoscopy (88% of initial attempts) and a bougie (68% of initial attempts) were commonly used adjuncts. For 345 of 578 patients (60%), the laryngeal tube was removed before intubation attempts. For 112 of 578 patients (19%), the first intubation attempt occurred with the deflated laryngeal tube left in place. Three patients (<1%) required a surgical airway.

CONCLUSION

In this cohort, emergency physicians successfully exchanged an out-of-hospital laryngeal tube for an endotracheal tube, using commonly available airway management techniques. ED clinicians should be familiar with techniques for exchanging out-of-hospital extraglottic airways for an endotracheal tube.

EMT-led laryngeal tube vs. face-mask ventilation during cardiopulmonary resuscitation - a multicenter prospective randomized trial

Background

Laryngeal tube (LT) application by rescue personnel as an alternate airway during the early stages of out-of-hospital cardiac arrest (OHCA) is still subject of debate. We evaluated ease of handling and efficacy of ventilation administered by emergency medical technicians (EMTs) using LT and bag-valve-mask (BVM) during cardiopulmonary resuscitation of patients with OHCA.

Methods

An open prospective randomized multicenter study was conducted at six emergency medical services centers over 18 months. Patients in OHCA initially resuscitated by EMTs were enrolled. Ease of handling (LT insertion, tight seal) and efficacy of ventilation (chest rises visibly, no air leak) with LT and BVM were subjectively assessed by EMTs during pre-study training and by the attending emergency physician on the scene. Outcome and frequency of complications were compared.

Results

Of 97 eligible patients, 78 were enrolled. During pre-study training EMTs rated efficacy of ventilation with LT higher than with BVM (66.7% vs. 36.2%, p = 0.022), but efficacy of on-site ventilation did not differ between the two groups (71.4% vs. 58.5%, p = 0.686). Frequency of complications (11.4% vs. 19.5%, p = 0.961) did not differ between the two groups.

Conclusions

EMTs preferred LT ventilation to BVM ventilation during pre-study training, but on-site there was no difference with regard to efficacy, ventilation safety, or outcome. The results indicate that LT ventilation by EMTs during OHCA is not superior to BVM and cannot substitute for BVM training. We assume that the main benefit of the LT is the provision of an alternative airway when BVM ventilation fails. Training in BVM ventilation remains paramount in EMT apprenticeship and cannot be substituted by LT ventilation.

Trial registration

ClinicalTrials.gov (NCT01718795).

Electronic supplementary material

The online version of this article (10.1186/s13049-017-0446-1) contains supplementary material, which is available to authorized users.

Advanced Airway Type and Its Association with Chest Compression Interruptions During Out-of-Hospital Cardiac Arrest Resuscitation Attempts

OBJECTIVE

To assess interruptions in chest compressions associated with advanced airway placement during cardiopulmonary resuscitation (CPR) of out-of-hospital cardiac arrest (OHCA) victims.

METHODS

The method used was observational analysis of prospectively collected clinical and defibrillator data from 339 adult OHCA victims, excluding victims with <5 minutes of CPR. Interruptions in CPR, summarized by chest compression fraction (CCF), longest pause, and the number of pauses greater than 10 seconds, were compared between patients receiving bag valve mask (BVM), supraglottic airway (SGA), endotracheal intubation (ETI) via direct laryngoscopy (DL), and ETI via video laryngoscopy (VL). Secondary outcomes included first pass success and the effect of multiple airway attempts on CPR interruptions.

RESULTS

During the study period, paramedics managed 23 cases with BVM, 43 cases with SGA, 148 with DL, and 125 with VL. There were no statistically significant differences between the airway groups with regard to longest compression pause (BVM 18 sec [IQR 11-33], SGA 29 sec [IQR 15-65], DL 26 sec [IQR 12-59], VL 22 sec [IQR 14-41]), median number of pauses greater than 10 seconds (BVM 2 [IQR 1-3], SGA 2 [IQR 1-3], DL 2 [IQR 1-4], VL 2 [IQR 1-3]), or CCF (0.92 for all groups). However, each additional attempt following failed initial DL was associated with an increase in the risk of additional chest compression pauses (relative risk 1.29, 95% confidence interval 1.02-1.64). Such an association was not observed with additional attempts using VL or SGA. First pass success was highest with SGA (77%), followed by between DL (68%) and VL (67%); these differences were not statistically significant.

CONCLUSIONS

While summary measures of chest compression delivery did not differ significantly between airway classes in this observational study, repeated attempts following failed initial DL during cardiopulmonary resuscitation were associated with an increase in the number of pauses in chest compression delivery observed.