Cricothyrotomy in the emergency department revisited

Prehospital Cricothyrotomy: A Narrative Review of Technical, Educational, and Operational Considerations for Procedure Optimization

BACKGROUND

Definitive airway management is a requisite skill in the prehospital setting, most often accomplished with either an endotracheal tube or supraglottic airway. When clinicians encounter a cannot oxygenate and cannot ventilate scenario, a patient's airway still must be secured. Prehospital cricothyrotomy is a high acuity, low frequency procedure used to secure the airway through the anterior neck. Patients who require cricothyrotomy often have significant comorbid conditions and mortality, and there can be a high rate of procedural complications. The ability to perform a cricothyrotomy is within the scope of practice for many prehospital clinicians and mastery of the procedure is crucial for patient outcomes. Despite this, initial training on the procedure is minimal, and paramedics report discomfort in their ability to perform the procedure.

OBJECTIVE

Review and summarize the best available evidence relating to the performance of cricothyrotomies and propose technical, educational, and operational considerations to minimize complications and optimize success of prehospital cricothyrotomies.

DISCUSSION

Technical considerations when performing cricothyrotomy in the prehospital setting can be used to mitigate airway misplacement, mainstem intubation, and hemorrhage. Educational consideration should include focus on a singular technique, use of established curriculum, spaced repetition with either simulation or mental practice, and a focus on intention training of when to perform the procedure. The preferred technique from the National Association of Emergency Medical Service (EMS) Physician guidelines is the surgical technique. Operational considerations to optimize a successful procedure should include checklists, preassembled kits, and robust quality improvement and insurance after a cricothyrotomy is performed.

CONCLUSIONS

By focusing on technical, educational, and operation considerations relating to prehospital cricothyrotomy, prehospital clinicians can optimize the chance for procedural success.

2024 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the eighth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recent published resuscitation evidence reviewed by the International Liaison Committee on Resuscitation task force science experts. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research.

2024 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the eighth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recent published resuscitation evidence reviewed by the International Liaison Committee on Resuscitation task force science experts. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research.

In the Nick of Time-Emergency Front-of-Neck Airway Access

Emergency front-of-neck access refers to all techniques that deliver oxygen into the airway lumen through the anterior neck structures and encompasses access both through the cricothyroid membrane and the tracheal wall. There has yet to be a universal agreement regarding the preferred technique. A surgical incision is currently the most common approach in prehospital and in-hospital care. This review intends to review and summarize the existing clinical, basic science, and societal guidelines for eFONA.

Current trends in emergency airway management: a clinical review

Airway management is a fundamental and complex process that involves a sequence of integrated tasks. Situations requiring emergency airway management may occur in the emergency department, intensive care units, and various other clinical spaces. A variety of challenges can arise during emergency airway preparation, intubation, and postintubation, which may result in significant complications for patients. Therefore, many countries are establishing step-by-step systemization and detailed guidelines and/or updating their content based on the latest research. This clinical review introduces the current trends in emergency airway management, such as emergency airway management algorithms, comparison of video and direct laryngoscopy, rapid sequence intubation, pediatric airway management, prehospital airway management, surgical airway management, and airway management education.

Emergency front-of-neck access in cardiac arrest: A scoping review

BACKGROUND

Airway management is a core component of the treatment of cardiac arrest. Where a rescuer cannot establish a patent airway to provide oxygenation and ventilation using standard basic and advanced airway techniques, there may be a need to consider emergency front-of-neck airway access (eFONA, e.g., cricothyroidotomy), but there is limited evidence to inform this approach.

OBJECTIVES

This scoping review aims to identify the evidence for the use of eFONA techniques in patients with cardiac arrest.

METHODS

In November 2023, we searched Medline, Embase, and Cochrane Central to identify studies on eFONA in adults. We included randomised controlled trials, non-randomised studies, and case series with at least five cases that described any use of eFONA. We extracted data, including study setting, population characteristics, intervention characteristics, and outcomes. Our analysis focused on four key areas: incidence of eFONA, eFONA success rates, clinical outcomes, and complications.

RESULTS

The search identified 21,565 papers, of which 18,934 remained after de-duplication. After screening, we included 69 studies (53 reported incidence, 40 reported success rate, 38 reported clinical outcomes; 36 studies reported complications). We identified only one randomised controlled trial. Across studies, there was a total of 4,457 eFONA attempts, with a median of 31 attempts (interquartile range 16-56.5) per study. There was marked heterogeneity across studies that precluded any pooling of data. There were no studies that included only patients in cardiac arrest.

CONCLUSION

The available evidence for eFONA is extremely heterogeneous, with no studies specifically focusing on its use in adults with cardiac arrest.

Anatomical morphometry for Cricothyrotomy puncture and incision

PURPOSE

Emergency surgical airway securing techniques include cricothyrotomy, puncture, and incision. While the instruments used for these methods vary in size, no index of laryngeal morphology exists to guide instrument selection. Therefore, we measured the morphology of the cricothyroid ligament in Japanese individuals and assessed its correlations with height.

METHODS

This retrospective study used 61 anatomical practice specimens. The cricothyroid ligament of the laryngeal area was dissected, and a frontal image was recorded. Next, images of the midsagittal sections of the larynx and trachea were recorded. The width and height of the cricothyroid ligament were measured from the frontal images, and the depth of the larynx and the angle to the lower edge of the cricothyroid plate were measured from the mid-sagittal cross-sectional images. The height was estimated from the tibial lengths of the specimens and statistically analyzed for correlations. 　 RESULTS: The width and depth were significantly greater in males. Overall, there was a slight correlation between the results of each laryngeal measurement and estimated height for all items.

CONCLUSION

The morphology of cricothyrotomy revealed that the width and depth of the laryngeal area varied according to sex. Moreover, the results also showed a correlation with the estimated height. Thus, it is important to predict the morphology of the laryngeal area and cricothyroid ligament by considering factors such as patient sex, weight, and height.

[Cricothyrotomy : Data situation, guidelines and techniques for the definitive surgical airway]

Cricothyrotomy represents the final approach to secure the airway, in the course of which less invasive measures have failed. It can also primarily be carried out to establish a secure airway. This is essential to protect the patient from a significant hypoxia. This is a cannot ventilate-cannot oxygenate (CVCO) situation, which presumably all colleagues in emergency intensive care medicine and anesthesia have already been confronted with. Evidence-based algorithms for the management of a difficult airway and CVCO have been established. If oxygenation using an endotracheal tube, an extraglottic airway device or bag-valve mask ventilation all fail, the airway must be surgically secured, i.e. using cricothyrotomy. The prevalence of the CVCO situation in a prehospital setting is ca. 1%. No valid prospective randomized in vivo studies have been carried with respect to the question of the best method.

Role of ultrasonography in an impalpable tissue larynx model during a simulated front-of-neck access scenario: a randomized simulation study

PURPOSE

A large vertical incision is recommended when performing front-of-neck access in patients with impalpable neck landmarks during a cannot intubate-cannot oxygenate (CICO) scenario. We investigated the impact of ultrasonography on vertical incision size of a front-of-neck access on an ultrasound-compatible impalpable porcine larynx model.

METHODS

Emergency medicine and anesthesia trainees were randomized to the Ultrasound (US, n = 21) and Non-Ultrasound (NUS, n = 21) groups. Within 1 week after a teaching session on airway ultrasound and Scalpel-Bougie-Tube (SBT) technique, participants were instructed to perform cricothyroidotomy on the model during a simulated cannot intubate-cannot oxygenate scenario. The primary outcome was a vertical size incision. Secondary outcomes were procedural completion time, horizontal size incision, tissue injury severity, and correct tube placement.

RESULTS

The ultrasound group performed a significantly smaller vertical incision [median (IQR), 35.0 (15, 40) vs 65.0 (52, 100) mm (95% CI) - 30.0 (- 55.1, - 4.9), p = 0.02] and took longer total time to complete the procedure [median (IQR), 200.5 (126, 267) vs 93.5 (71.0, 167.5) secs (95% CI) 91.0 (3.73, 178.3), p = 0.04]. Tissue injury severity and correct tube placement were similar between groups.

CONCLUSIONS

Ultrasound-guided identification of the cricothyroid membrane significantly reduced the recommended vertical incision size with similar success rates. However, there was an increased time when performing a Scalpel-Bougie-Tube cricothyroidotomy on an impalpable porcine larynx model by physicians in training. Ultrasonography should not be used in an emergency scenario of airway rescue. Its potential use to pre-mark the cricothyroid membrane should be considered in difficult airway management of impalpable neck.

Characterization of Puncture Forces of the Human Trachea and Cricothyroid Membrane

Accurate human tissue biomechanical data represents a critical knowledge gap that will help facilitate the advancement of new medical devices, patient-specific predictive models, and training simulators. Tissues related to the human airway are a top priority, as airway medical procedures are common and critical. Placement of a surgical airway, though less common, is often done in an emergent (cricothyrotomy) or urgent (tracheotomy) fashion. This study is the first to report relevant puncture force data for the human cricothyroid membrane and tracheal annular ligaments. Puncture forces of the cricothyroid membrane and tracheal annular ligaments were collected from 39 and 42 excised human donor tracheas, respectively, with a mechanized load frame holding various surgical tools. The average puncture force of the cricothyroid membrane using an 11 blade scalpel was 1.01 ± 0.36 N, and the average puncture force of the tracheal annular ligaments using a 16 gauge needle was 0.98 ± 0.34 N. This data can be used to inform medical device and airway training simulator development as puncture data of these anatomies has not been previously reported.

Emergency Airway Management in a Patient with a T-Tube Tracheal Stent

BACKGROUND

Abnormal anatomy complicates emergency airway management. In this case, we describe definitive airway management in a critically injured emergency department (ED) patient with a history of partial tracheal resection who had a Montgomery T-tube, a type of T-shaped tracheal stent, in place at the time of the motor vehicle collision. The Montgomery T-tube is not a useful artificial airway during resuscitation, as it lacks a cuff or the necessary adapter for positive pressure ventilation.

CASE REPORT

We describe a case of a 51-year-old man who required emergency airway management after a motor vehicle collision. The patient had a Montgomery T-tube in place, which was removed with facilitation by ketamine sedation and topical anesthesia. The patient was successfully intubated through the tracheal stoma after removal of the T-tube. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians must recognize the Montgomery T-tube, which resembles a standard tracheostomy tube externally, and have some understanding of how to manage a critically ill patient with this rare device in place. When a patient with a Montgomery T-tube in place requires positive pressure ventilation, the device may require emergent removal and replacement with a cuffed tracheostomy or endotracheal tube.

Prehospital Surgical Airway Management: An NAEMSP Position Statement and Resource Document

Bag-valve-mask ventilation and endotracheal intubation have been the mainstay of prehospital airway management for over four decades. Recently, supraglottic device use has risen due to various factors. The combination of bag-valve-mask ventilation, endotracheal intubation, and supraglottic devices allows for successful airway management in a majority of patients. However, there exists a small portion of patients who are unable to be intubated and cannot be adequately ventilated with either a facemask or a supraglottic airway. These patients require an emergent surgical airway. A surgical airway is an important component of all airway algorithms, and in some cases may be the only viable approach; therefore, it is imperative that EMS agencies that are credentialed to manage airways have the capability to perform surgical airways when appropriate. The National Association of Emergency Medical Services Physicians (NAEMSP) recommends the following for emergency medical services (EMS) agencies that provide advanced airway management.A surgical airway is reasonable in the prehospital setting when the airway cannot be secured by less invasive means.When indicated, a surgical airway should be performed without delay.A surgical airway is not a substitute for other airway management tools and techniques. It should not be the only rescue option available.Success of an open surgical approach using a scalpel is higher than that of percutaneous Seldinger techniques or needle-jet ventilation in the emergency setting.

High Success Rate of Prehospital and En Route Cricothyroidotomy Performed in the Israel Defense Forces: 20 Years of Experience

INTRODUCTION

Securing the airway is a crucial stage of trauma care. Cricothyroidotomy (CRIC) is often addressed as a salvage procedure in complicated cases or following a failed endotracheal intubation (ETI). Nevertheless, it is a very important skill in prehospital settings, such as on the battlefield.

HYPOTHESIS/PROBLEM

This study aimed to review the Israel Defense Forces (IDF) experience with CRIC over the past two decades.

METHODS

The IDF Trauma Registry (IDF-TR) holds data on all trauma casualties (civilian and military) cared for by military medical teams since 1997. Data of all casualties treated by IDF from 1998 through 2018 were extracted and analyzed to identify all patients who underwent CRIC procedures.Variables describing the incident scenario, patient's characteristics, injury pattern, treatment, and outcome were extracted. The success rate of the procedure was described, and selected variables were further analyzed and compared using the Fisher's-exact test to identify their effect on the success and failure rates. Odds Ratio (OR) was further calculated for the effect of different body part involvement on success and for the mortality after failed ETI.

RESULTS

One hundred fifty-three casualties on which a CRIC attempt was made were identified from the IDF-TR records. The overall success rate of CRIC was reported at 88%. In patients who underwent one or two attempts, the success rate was 86%. No difference was found across providers (physician versus paramedic). The CRIC success rates for casualties with and without head trauma were 80% and 92%, respectively (P = .06). Overall mortality was 33%.

CONCLUSIONS

This study shows that CRIC is of merit in airway management as it has shown to have consistently high success rates throughout different levels of training, injuries, and previous attempts with ETI. Care providers should be encouraged to retain and develop this skill as part of their tool box.

Emergency cricothyrotomy in morbid obesity: comparing the bougie-guided and traditional techniques in a live animal model

BACKGROUND

Cricothyrotomy is a rare, time sensitive procedure that is more challenging to perform when anatomical landmarks are not easily palpated before the initial incision. There is a paucity of literature describing the optimal technique for cricothyrotomy in patients with impalpable airway structures, such as in morbid obesity. In this study, we used a live sheep model of morbid obesity to compare the effectiveness of two common cricothyrotomy techniques.

METHODS

We randomly assigned emergency medicine residents to perform one of two cricothyrotomy techniques on a live anesthetized sheep. To simulate the anterior soft tissue neck thickness of an adult with morbid obesity we injected 120 mL of a mixture of autologous blood and saline into the anterior neck of the sheep. The traditional technique (as described in the New England Journal Video titled "Cricothyroidotomy") used a Shiley tracheostomy tube and no bougie, and the bougie-guided technique used a bougie and a standard endotracheal tube. The primary outcome was the total procedure time; the secondary outcome was first attempt success.

RESULTS

23 residents were included, 11 assigned to the bougie-guided technique and 12 to the traditional technique. After injection of blood and saline, the median depth from skin to cricothyroid membrane was 3.0 cm (IQR 2.5-3.4 cm). The median time for the bougie technique was 118 s (IQR 77-200 s) compared to 183 s (IQR 134-270 s) for the traditional technique (median difference 62 s, 95% CI 10-144 s). Success on the first attempt occurred in 7/11 (64%) in the bougie group and 6/12 (50%) in the traditional technique group.

CONCLUSION

In this study, which simulated morbid obesity on a living animal model complete with active hemorrhage and time pressure caused by extubation before the procedure, the bougie-guided technique was faster than the traditional technique using a tracheostomy tube without a bougie.

Proposed Mechanism-Based Risk Stratification and Algorithm to Prevent Sudden Death in Epilepsy

Sudden Unexpected Death in Epilepsy (SUDEP) is the leading cause of death in young adults with uncontrolled seizures. First aid guidance to prevent SUDEP, though, has not been previously published because the rarity of monitored cases has made the underlying mechanism difficult to define. This starkly contrasts with the first aid guidelines for sudden cardiac arrest that have been developed based on retrospective studies and expert consensus and the discussion of resuscitation challenges in various American Heart Association certificate courses. However, an increasing amount of evidence from documented SUDEP cases and near misses and from animal models points to a consistent sequence of events that starts with sudden airway occlusion and suggests a mechanistic basis for enhancing seizure first aid. In monitored cases, this sudden airway occlusion associated with seizure activity can be accurately inferred from inductance plethysmography or (depending on recording bandwidth) from electromyographic (EMG) bursts that are associated with inspiratory attempts appearing on the electroencephalogram (EEG) or the electrocardiogram (ECG). In an emergency setting or outside a hospital, seizure first aid can be improved by (1) keeping a lookout for sudden changes in airway status during a seizure, (2) distinguishing thoracic and abdominal movements during attempts to inspire from effective breathing, (3) applying a simple maneuver, the laryngospasm notch maneuver, that may help with airway management when aggressive airway management is unavailable, (4) providing oxygen early as a preventative step to reduce the risk of death, and (5) performing cardiopulmonary resuscitation before the limited post-ictal window of opportunity closes. We propose that these additions to first aid protocols can limit progression of any potential SUDEP case and prevent death. Risk stratification can be improved by recognition of airway occlusion, attendant hypoxia, and need for resuscitation.

Developing Cricothyroidotomy Skills Using a Biomaterial-Covered Model

INTRODUCTION

Cricothyroidotomy is an advanced and life-saving technique, but it is also a rare and a difficult procedure. The purpose of the present study was to produce a low-cost simulation model with realistic anatomic features to investigate its effectiveness in developing cricothyroidotomy skills.

METHODS

This study was performed at a university simulation center with 57 second-year student paramedics and a cricothyroidotomy simulation model. Total scores were assessed using a checklist. This consisted of 13 steps and was scored as misapplication/omission=0, correct performance and timing with hesitation=1, and correct performance and timing without hesitation=2. One of these steps, local anesthesia of the area if time is available, was not performed owing to time limitations. The highest possible score was 24. Data are presented as mean±SD with range, as appropriate. Normal distribution was evaluated using the Kolmogorov-Smirnov test, Student t test, and Mann-Whitney U test, and correlation analysis was used for statistical analysis.

RESULTS

Students completed the cricothyroidotomy procedure steps in 116±46 (55-238) s. At performance assessment, the score achieved was 12±5 (2-24). The highest total score of 24 was achieved by 3 students (5%). Total scores exhibited negative and significant correlation with procedure time (r=-0.403, P=0.002).

CONCLUSIONS

The model developed in this study is an inexpensive and effective method that can be used in cricothyroidotomy training for student paramedics. We think that repeating the cricothyroidotomy procedure on the model will increase success levels.

Ultrasound for airway management: An evidence-based review for the emergency clinician

BACKGROUND

Airway management is a common procedure performed in the Emergency Department with significant potential for complications. Many of the traditional physical examination maneuvers have limitations in the assessment and management of difficult airways. Point-of-care ultrasound (POCUS) has been increasingly studied for the evaluation and management of the airway in a variety of settings.

OBJECTIVE

This article summarizes the current literature on POCUS for airway assessment, intubation confirmation, endotracheal tube (ETT) depth assessment, and performing cricothyroidotomy with an emphasis on those components most relevant for the Emergency Medicine clinician.

DISCUSSION

POCUS can be a useful tool for identifying difficult airways by measuring the distance from the skin to the thyrohyoid membrane, hyoid bone, or epiglottis. It can also predict ETT size better than age-based formulae. POCUS is highly accurate for confirming ETT placement in adult and pediatric patients. The typical approach involves transtracheal visualization but can also include lung sliding and diaphragmatic elevation. ETT depth can be assessed by visualizing the ETT cuff in the trachea, as well as using lung sliding and the lung pulse sign. Finally, POCUS can identify the cricothyroid membrane more quickly and accurately than the landmark-based approach.

CONCLUSION

Airway management is a core skill in the Emergency Department. POCUS can be a valuable tool with applications ranging from airway assessment to dynamic cricothyroidotomy. This paper summarizes the key literature on POCUS for airway management.

The REAL CRIC Trainer: Instructions for Building an Inexpensive, Realistic Cricothyrotomy Simulator With Skin and Tissue, Bleeding, and Flash of Air

BACKGROUND

Surgical cricothyrotomy is a rare procedure but it must be mastered by any physician who is involved in advanced airway management. Lack of experience and practice, the high-stress nature of a "can't intubate, can't oxygenate" emergency, and the unavailability of realistic simulators all contribute to physician hesitance and inaptitude while employing cricothyrotomy during difficult and failed airways. The REAL CRIC Trainer was created to alleviate some of the barriers surrounding a surgical airway. It is designed to provide the user an affordable, easy to replicate, reusable, and extremely realistic experience in cricothyrotomy to prepare for this rare event.

DISCUSSION

The REAL CRIC Trainer uses a 3-dimensional printed tracheal model that is covered with pork belly skin, replicating human neck tissue. Red dyed normal saline is connected to the pork belly using intravenous tubing to simulate bleeding as an incision is made into the porcine skin. A bag-valve-mask connected to an endotracheal tube and to the trachea model will simulate breathing and replicate the puff of air experienced as the cricothyroid membrane is pierced with a scalpel. This simulator is cost effective and easy to replicate. Detailed step-by-step instructions are provided so that physicians working in any specialty involved in advanced airway management can easily recreate this trainer.

CONCLUSIONS

This simulator makes it practical for physicians in a variety of clinical settings to incorporate its use into regular practice sessions, thereby assuring that physicians are ready to perform an emergent cricothyrotomy if necessary.

Cricothyroid Approach for Emergency Access to the Airway

Airway emergencies are life-threatening events that face providers of many different backgrounds. In cannot-intubate-cannot-ventilate situations, emergent access to the airway can be obtained through the cricothyroid membrane by cricothyroidotomy. The 3 main techniques are open, percutaneous, and needle cricothyroidotomy. To date, there is no compelling evidence demonstrating superiority of a particular approach. Ultimately, the method used for cricothyroidotomy should be based on the comfort and experience of the provider performing the procedure.

Point-of-care ultrasound (POCUS) of the upper airway

Airway management is a critical skill in the practice of several medical specialities including anesthesia, emergency medicine, and critical care. Over the years mounting evidence has showed an increasing role of ultrasound (US) in airway management. The objective of this narrative review is to provide an overview of the indications for point-of-care ultrasound (POCUS) of the upper airway. The use of US to guide and assist clinical airway management has potential benefits for both provider and patient. Ultrasound can be utilized to determine airway size and predict the appropriate diameter of single-lumen endotracheal tubes (ETTs), double-lumen ETTs, and tracheostomy tubes. Ultrasonography can differentiate tracheal, esophageal, and endobronchial intubation. Ultrasonography of the neck can accurately localize the cricothyroid membrane for emergency airway access and similarly identify tracheal rings for US-guided tracheostomy. In addition, US can identify vocal cord dysfunction and pathology before induction of anesthesia. A rapidly growing body of evidence showing ultrasonography used in conjunction with hands-on management of the airway may benefit patient care. Increasing awareness and use of POCUS for many indications have resulted in technologic advancements and increased accessibility and portability. Upper airway POCUS has the potential to become the first-line non-invasive adjunct assessment tool in airway management.

Quick Response Tracheotomy: A Novel Surgical Procedure

Quick response tracheostomy (QRT) is a novel open surgical technique to emergently establish an airway. The method is simple; the skills necessary to perform this procedure are rapidly acquired; and it is expedient, minimally traumatic, and remarkably devoid of complications often encountered with percutaneous dilatational tracheotomies, including those complications seen with cricothyroidotomies. Unlike all other tracheotomies in which considerable blunt dissection is required, QRT avoids tissue crushing because sharp dissection alone is used to acquire surgical access to the trachea. The QRT does not entail inserting a guidewire into the trachea, a standard feature for percutaneous tracheal access; it avoids any risk of unintended laceration of the posterior tracheal wall and proximal subjacent esophagus. The technique averts tracheal ring fracture and tracheoesophageal fistula complications. The QRT has a uniquely low incidence of inducing hemorrhage, and it requires no steps that cause temporary tracheal occlusion and will therefore not facilitate hypoxia. The QRT contributes minimally to conditions favorable for generating subglottic stenosis, and the procedure is swiftly executed with very low probability for external tracheal placement of the tracheostomy tube. The QRT is not a blind procedure. No special instruments are required for its execution nor is concurrent tracheoscopy required at any stage while performing a QRT as is specified for percutaneous tracheotomies.

The role of cricothyrotomy, tracheostomy, and percutaneous tracheostomy in airway management

Cricothyrotomy, percutaneous dilation tracheostomy, and surgical tracheostomy are cost-effective and safe techniques employed in the management of critically ill patients requiring insertion of an artificial airway. These procedures have been well characterized and studied in the surgical, emergency medicine, and critical care literature. This article focuses on the role of each of these modalities in airway management, specifically comparing the data for each procedure in regard to procedural outcomes. The authors discuss the techniques available and the relevant background data regarding choice of each method and its integration into clinical practice.

Ultrasound Improves Cricothyrotomy Success in Cadavers with Poorly Defined Neck Anatomy

Background

Misidentification of the cricothyroid membrane in a “cannot intubate-cannot oxygenate” situation can lead to failures and serious complications. The authors hypothesized that preprocedure ultrasound-guided identification of the cricothyroid membrane would reduce complications associated with cricothyrotomy.

Methods

A group of 47 trainees were randomized to digital palpation (n = 23) and ultrasound (n = 24) groups. Cricothyrotomy was performed on human cadavers by using the Portex® device (Smiths Medical, USA). Anatomical landmarks of cadavers were graded as follows: grade 1—easy = visual landmarks; 2—moderate = requires light palpation of landmarks; 3—difficult = requires deep palpation of landmarks; and 4—impossible = landmarks not palpable. Primary outcome was the complication rate as measured by the severity of injuries. Secondary outcomes were correct device placement, failure to cannulate, and insertion time.

Results

Ultrasound guidance significantly decreased the incidence of injuries to the larynx and trachea (digital palpation: 17 of 23 = 74% vs. ultrasound: 6 of 24 = 25%; relative risk, 2.88; 95% CI, 1.39 to 5.94; P = 0.001) and increased the probability of correct insertion by 5.6 times (P = 0.043) in cadavers with difficult and impossible landmark palpation (digital palpation 8.3% vs. ultrasound 46.7%). Injuries were found in 100% of the grades 3 to 4 (difficult–impossible landmark palpation) cadavers by digital palpation compared with only 33% by ultrasound (P < 0.001). The mean (SD) insertion time was significantly longer with ultrasound than with digital palpation (196.1 s [60.6 s] vs. 110.5 s [46.9 s]; P < 0.001).

Conclusion

Preprocedure ultrasound guidance in cadavers with poorly defined neck anatomy significantly reduces complications and improves correct insertion of the airway device in the cricothyroid membrane.

The inaccuracy of using landmark techniques for cricothyroid membrane identification: a comparison of three techniques

OBJECTIVES

Successful cricothyrotomy is predicated on accurate identification of the cricothyroid membrane (CTM) by palpation of superficial anatomy. However, recent research has indicated that accuracy of the identification of the CTM can be as low as 30%, even in the hands of skilled providers. To date, there are very little data to suggest how to best identify this critical landmark. The objective was to compare three different methods of identifying the CTM.

METHODS

A convenience sample of patients and physician volunteers who met inclusion criteria was consented. The patients were assessed by physician volunteers who were randomized to one of three methods for identifying the CTM (general palpation of landmarks vs. an approximation based on four finger widths vs. an estimation based on overlying skin creases of the neck). Volunteers would then mark the skin with an invisible but florescent pen. A single expert evaluator used ultrasound to identify the superior and inferior borders of the CTM. The variably colored florescent marks were then visualized with ultraviolet light and the accuracy of the various methods was recorded as the primary outcome. Additionally, the time it took to perform each technique was measured. Descriptive statistics and report 95% confidence intervals (CIs) are reported.

RESULTS

Fifty adult patients were enrolled, 52% were female, and mean body mass index was 28 kg/m(2) (95% CI = 26 to 29 kg/m(2) ). The general palpation method was successful 62% of the time (95% CI = 48% to 76%) and took an average of 14 seconds to perform (range = 5 to 45 seconds). In contrast, the four-finger technique was successful 46% of the time (95% CI = 32% to 60%) and took an average of 12 seconds to perform (range = 6 to 40 seconds). Finally, the neck crease method was successful 50% of the time (95% CI = 36% to 64%) and took an average of 11 seconds to perform (range = 5 to 15 seconds).

CONCLUSIONS

All three methods performed poorly overall. All three techniques might potentially be even less accurate in instances where the superficial anatomy is not palpable due to body habitus. These findings should alert clinicians to the significant risk of a misplaced cricothyrotomy and highlight the critical need for future research.

Emergency Cricothyroidotomy for Difficult Airway Management After Asynchronous Bilateral Neck Dissections: A Case Report and Literature Review

PURPOSE

This report describes a case that required emergency cricothyroidotomy for an upper airway obstruction owing to laryngeal edema after asynchronous bilateral neck dissections.

PATIENT AND METHODS

A 57-year-old man was diagnosed with multicentric squamous cell carcinoma of the tongue (T1 and 2N0M0), and partial glossectomy with primary closure was performed. Three months after surgery, secondary metastases in the right cervical lymph nodes were detected, and a right radical neck dissection was performed. Contrast-enhanced computed tomographic (CT) scan taken 2 weeks after the right neck dissection visualized a possible third metastasis in the left cervical lymph node. Four weeks after the right radical neck dissection, left supraomohyoid neck dissection was carried out. In this surgery, the left internal jugular vein (IJV) was preserved. Nine hours after surgery, severe swelling of the face and pharynx was recognized, resulting in a stoppage of respiration and then an emergency cricothyroidotomy.

RESULTS

The patient's life was saved without any encephalopathy or airway trouble. Contrast-enhanced CT scan taken the next day confirmed the preserved left IJV patency.

CONCLUSION

Oral and maxillofacial surgeons should be aware of the possibility of life-threatening laryngeal edema associated with bilateral neck dissections even if the unilateral IJV is preserved and should know the procedure for emergency cricothyroidotomy.

A survey of graduating emergency medicine residents' experience with cricothyrotomy

Introduction:

The Emergency Medicine (EM) Residency Review Committee stipulates that residents perform 3 cricothyrotomies in training but does not distinguish between those done on patients or via other training methods. This study was designed to determine how many cricothyrotomies residents have performed on living patients, the breadth and prevalence of alternative methods of instruction, and residents’ degree of comfort with performing the procedure unassisted.

Methods:

We utilized a web-based tool to survey EM residents nearing graduation and gathered data regarding the number of cricothyrotomies performed on living and deceased patients, animals, and models/simulators. Residents indicating experience with the procedure were asked additional questions as to the indication, supervision, and outcome of their most recent cricothyrotomy. We also collected data regarding experience with rescue airway devices, observation of cricothyrotomy, and comfort (“0–10” scale with “10” representing complete confidence) regarding the procedure.

Results:

Of 296 residents surveyed, 22.0% performed a cricothyrotomy on a living patient, and 51.6% had witnessed at least one performed. Those who completed a single cricothyrotomy reported a significantly greater level of confidence, 6.3 (95% confidence interval [CI] 5.7–7.0), than those who did none, 4.4 (95% CI 4.1–4.7), p<<0.001. Most respondents, 68.1%, had used the recently deceased to practice the technique, and those who had done so more than once reported higher confidence, 5.5 (95% 5.1–5.9), than those who had never done so, 4.1 (95% CI 3.7–4.5), p<<0.001. Residents who practiced cricothyrotomy on both simulators and the recently deceased expressed more confidence, 5.4 (95% CI 5.0–5.8), than those who used only simulators, 4.0 (95% CI 3.6–4.5), p<<0.001. Neither utilization of models, simulators, or animals, nor observance of others’ performance of the procedure independently affected reported confidence among residents.

Conclusion:

While prevalence of cricothyrotomy and reported comfort with the procedure remain low, performing the procedure on living or deceased patients increased residents’ confidence in undertaking an unassisted cricothyrotomy upon graduation in the population surveyed. There is evidence to show that multiple methods of instruction may yield the highest benefit, but further study is needed.

Emergency cricothyrotomy

Establishment of an unobstructed airway and adequate oxygenation is a basic tenet of life support. Mechanical or anatomic airway obstructions can arise secondary to trauma, pathology, foreign bodies, and infection. The oral and maxillofacial surgeon is uniquely trained to provide surgical and anesthetic care, and must be prepared to provide emergency airway management. This article reviews the indications, contraindications, and techniques of surgical and needle cricothyrotomy. Fortunately, with advances in airway techniques and equipment, emergency cricothyrotomy is not a common procedure. However, in the event that a surgeon has no other means of securing an airway, this procedure may avert a catastrophe. If such a situation does occur, quick and decisive action can best be carried out if there is a thorough understanding of the anatomy and techniques involved.

Cricothyrotomy technique using gum elastic bougie is faster than standard technique: a study of emergency medicine residents and medical students in an animal lab

OBJECTIVES

The objective was to compare time to completion, failure rate, and subjective difficulty of a new cricothyrotomy technique to the standard technique. The new bougie-assisted cricothyrotomy technique (BACT) is similar to the rapid four-step technique (RFST), but a bougie and endotracheal tube are inserted rather than a Shiley tracheostomy tube.

METHODS

This was a randomized controlled trail conducted on domestic sheep. During a 3-month period inexperienced residents or students were randomized to perform cricothyrotomy on anesthetized sheep using either the standard technique or the BACT. Operators were trained with an educational video before the procedure. Time to successful cricothyrotomy was recorded. The resident or student was then asked to rate the difficulty of the procedure on a five-point scale from 1 (very easy) to 5 (very difficult).

RESULTS

Twenty-one residents and students were included in the study: 11 in the standard group and 10 in the BACT group. Compared to the standard technique, the BACT was significantly faster with a median time of 67 seconds (interquartile range [IQR] = 55-82) versus 149 seconds (IQR = 111-201) for the standard technique (p = 0.002). The BACT was also rated easier to perform (median = 2, IQR = 1-3) than the standard technique (median = 3, IQR = 2-4; p = 0.04). The failure rate was 1/10 for the BACT compared to 3/11 for the standard method (p = NS).

CONCLUSIONS

This study demonstrates that the BACT is faster than the standard technique and has a similar failure rate when performed by inexperienced providers on anesthetized sheep.

Retrograde intubation

Airway management in the emergency department is a critical skill that must be mastered by emergency physicians. When rapid-sequence induction with oral-tracheal intubation performed by way of direct laryngoscopy is difficult or impossible due to a variety of circumstances, an alternative method or device must be used for a rescue airway. Retrograde intubation requires little equipment and has few contraindications. This technique is easy to learn and has a high level of skill retention. Familiarity with this technique is a valuable addition to the airway-management armamentarium of emergency physicians caring for ill or injured patients. Variations of the technique have been described, and their use depends on the individual circumstances.

Teaching lifesaving procedures: the impact of model fidelity on acquisition and transfer of cricothyrotomy skills to performance on cadavers

BACKGROUND

A decline in emergency surgical airway procedures in recent years has resulted in a decreased exposure to cricothyrotomy. Consequently, residents have very little experience or confidence in performing this intervention. In this study, we compared cricothyrotomy skills acquired on a simple inexpensive model to those learned on a high fidelity simulator using valid evaluation instruments and testing on cadavers.

METHODS

First and second year anesthesiology residents were recruited. All subjects performed a videotaped pretest cricothyrotomy on cadavers. Subjects were randomized into two groups: The high fidelity group (n = 11) performed two cricothyrotomies on a full-scale simulator with an anatomically accurate larynx. The low fidelity group (n = 11) performed two cricothyrotomies on a low fidelity model constructed from corrugated tubing. Within 2 wk all subjects performed a posttest. Two blinded examiners graded and timed the performances using a checklist and a global rating scale.

RESULTS

There was no significant difference in the change from pretest to posttest performance between the model groups as evaluated by all three measures (all: P = NS). Training on both models significantly improved performance on all measures (all: P < 0.001). Inter-rater reliability was strong (checklist: r = 0.90; global rating scale: r = 0.89).

CONCLUSIONS

Our study shows that a simple inexpensive model achieved the same effect on objectively rated skill acquisition as did an expensive simulator. The skills acquired on both models transferred effectively to cadavers. Training for this life-saving skill does not need to be limited by simulator accessibility or cost.

Utilization of the LifeStat Emergency Airway Device

Objectives:

Management of the airway in an emergency may be a harrowing experience. The equipment necessary to perform this procedure is often inaccessible. The LifeStat emergency airway is a portable device approved by the US Food and Drug Administration in 1997 for emergency cricothyrotomy. It is small enough to secure to a keychain, thus allowing instantaneous access at all times. We present a retrospective case series to report the experience of clinicians who have used the LifeStat device.

Methods:

A survey instrument was sent to a convenience sample of health-care professionals who purchased the LifeStat emergency airway. The survey queried device use, user demographics, and the success, ease, complications, and location of use.

Results:

One thousand surveys were distributed, and 100 individuals responded. Fifteen percent (15 of 100) reported use of the device on 17 occasions. The LifeStat was used successfully in all 17 cases. Eighty-two percent (14 of 17) of emergency use was in hospitals. In all cases the device was positioned successfully on the first attempt. No complications were reported.

Conclusions:

The LifeStat device provides a relatively safe and effective means of performing emergency cricothyrotomy. The majority of emergency situations in which the device was deployed occurred in hospital settings.

Airway Management in Trauma: An Update

This article reviews the more recent theoretic and practical information that pertains to airway management in the trauma setting. This is followed by a presentation of the newer airway devices that may be advantageous in the management of the airway in trauma as well as a discussion of other devices, techniques, or maneuvers that are useful in the trauma setting but may be underused. Each clinician needs to be knowledgeable about the various airway options and then, based on one's own particular skills and resources, construct an airway management algorithm that works best for him or her. Each clinician needs to be knowledgeable about the various airway options, and then, based on the clinician's particular skills and resources, construct an airway management algorithm that works best.

Needle vs surgical cricothyroidotomy: a short cut to effective ventilation

Cricothyroidotomy can be performed using three techniques. This literature review seeks to determine which is more appropriate for use in prehospital can't intubate/can't ventilate scenarios where laryngeal mask airways prove ineffective. The common approach of inserting a 14-gauge cannula and using low-pressure ventilation via intermittent occlusion of an opening in oxygen tubing (15 l x min(-1) flow) results in ineffective ventilation within 60 s or less, depending on the degree of airway obstruction. In the absence of a high degree of upper airway obstruction, ventilation can be effective if the cannula is attached to a high pressure (45 psi) jet ventilator, but such devices are rare in UK prehospital practice. A self-inflating bag used with a cuffed tube inserted through a horizontal scalpel incision provides sustained adequate ventilation, has a relatively low complication rate compared to needle cricothyroidotomy and is a skill that can be easily taught to paramedics, nurses and doctors.

Difficult airway management

Airway management is unequivocally the most important responsibility of the emergency physician. No matter how prepared for the task, no matter what technologies are utilized, there will be cases that are difficult. The most important part of success in the management of a difficult airway is preparation. When the patient is encountered, it is too late to check whether appropriate equipment is available, whether a rescue plan has been in place, and what alternative strategies are available for an immediate response. The following article will review the principles of airway management with an emphasis upon preparation, strategies for preventing or avoiding difficulties, and recommended technical details that hopefully will encourage the reader to be more prepared and technically skillful in practice.