In the constantly changing field of prehospital care, and in light of changing resuscitation priorities and practices, EMS systems have approached intubation in the field very differently. There are many different variations in systems, including who performs what skills and what the desired outcome is.
Although individual system success rates may seem high, there’s always an adverse outcome with any missed airway. To provide an exceptional application with the use of new tools, and to teach better skills while treating successfully on a regular basis, the EMS community strives to be as proficient as possible. Still, an all-inclusive study with advisement on improvement has yet to be published.
Some studies present data that field paramedics have an intubation fail rate of 25% on adults. However, the fail rate for pediatrics is almost twice that rate.1
Only a small number of intubations were actually not recognized in the field. In a Denver study of 825 field attempts, 170 were recognized as being an unsuccessfully placed airway that resulted in the need to use other means.1
The issues prehospital providers face include: competency, skill frequency and retention, frequency and quality of retraining, the need for intubation, and the risk and liability with misplaced tubes. Litigation can result after a misplaced airway if the paramedics placing the endotracheal (ET) tube fail to identify and correct the misplacement.
Regarding litigation, there are many people in the field who can act as professional witnesses, as seen in an asthma case where a patient was being treated with an advanced airway placement. The treating paramedic didn’t use the tools available to confirm proper placement. The expert then testified that the standard hadn’t been met by the service to require end-tidal carbon dioxide monitoring or the use of a colorimetric (a standard device) to check for proper placement.2
A colorimetric CO2 detector attaches directly to the endotracheal tube and responds quickly to exhaled CO2 with a simple color change. Photo Grant Therrien
Many tools are available to help with proper placement and are often required by many agencies. In two groups being represented in a study, one used an end-tidal device to verify tube placement and saw only a 4.6% failed attempt rate while the group that didn’t use any type of device to verify tube placement experienced a 7.4% failure rate.1
IMPORTANCE OF AIRWAY MONITORING
All services should require continuous airway monitoring and assure their paramedics have the ability to identify when a tube becomes misplaced during transport. In the Denver study, few of the crews used continuous CO2 monitoring, but now this level of monitoring has become a standard of care and many systems are pushing for more frequent and better quality education.1
Other training is equally important because intubation is a central skill, but not a well-managed one. In a year-long airway management study of 1,200 paramedics working in the area of interest, only 926 intubations were attempted.1 At this rate, each paramedic attempted only 0.8 intubations a year, or less than one in a calendar year. Although this low rate is alarming at face value, it becomes a more serious issue if you consider that one paramedic may have intubated three times while others didn’t intubate at all.
Commonly, many EMS providers don’t receive the training to better their airway management knowledge, even though much of our industry relies on simply teaching motor skills. Many systems hope that repeating these skills on a regular basis will allow for better retention and expertise, but that philosophy isn’t carried through in a paramedic’s training. Of all medical professionals, paramedics are required to perform the lowest amount of intubations during their training, with an average of 10. Still, the standard national curriculum only recommends five.3
Other types of medical professionals who train for intubation have a much higher contact rate. Emergency residents must perform as many as 35 intubations in training, anesthesia residents are required to perform 60 supervised intubations during training, and nurse anesthetists often have to perform 200.3 Many times when a system is seen as having low intubation rates per medic, the supraglottic airway becomes the primary airway method.4
Instilling confidence in new paramedics during field training must be continuous throughout their careers in order to maintain a high skill level. During a case study in a large Midwest city, a paramedic was witnessed by other responders on scene violently and repeatedly trying to intubate a patient. The patient had a poor outcome, showing signs of subcutaneous air. The medical investigator’s exam revealed the patient had a large tracheal tear caused by the improperly used ET tube.2
ALTERNATIVE AIRWAY MANAGEMENT TOOLS
Skills can and should be monitored. Taking the first step to educate and monitor proficiency is important.3 But because of the difficulty to find time for training and the decreased availability of trained personnel, new and more effective approaches to intubation are starting to become available; blind airway management tools are becoming more and more mainstream every day. These devices isolate the trachea and ventilate through the glottis opening.
Alternatives such as King Airway and Laryngeal Mask Airway (LMA) devices are now in use in many systems and required prior to ET intubation, not just because of ease of use and reduced risk of liability, but to ensure there’s no delay or interruption in delivery of chest compressions during the early phases of cardiac arrests. Many operating rooms have also transitioned from tracheal intubation to using similar airway management techniques.3
Utilizing a King Airway helps to ensure there’s no delay or interruption in delivery of chest compressions during the early phases of cardiac arrest. Photo Criss Brainard
BASIC AIRWAY MANAGEMENT
Time in the arrested patient is critical and the ability to place an airway quickly is very important. With less training required, many systems are also allowing the use of supraglottic airways by BLS providers. The airway is much easier to insert with less time taken. In addition, the use of supraglottic airway as a primary airway may be best with some patients presenting difficult airways, such as morbidly obese patients who are often difficult to visualize directly.5
Of the recognized unsuccessful intubations in the field, many were managed with BLS techniques like airway adjuncts and bag-valve mask, although some had supraglottic airways in place upon arrival at the hospital.1Many times, with difficult airways, as in a trauma patient with head and/or chest trauma, it’s important to realize that other forms of airway management should be used to prevent failed attempts at tracheal intubation.6
Supraglottic airways are generally seen as less secure airways than ET tubes, but there’s no data to support this.3 Most studies also don’t currently show a different outcome in field vs. in-hospital airway management, but one study did indicate there was an increase in mortality when patients were intubated in the field.7
ADVANCED AIRWAY MANAGEMENT
The difficulty in advanced airway management becomes greater as our patients become smaller. In adults, missed and failed intubations occur in 30% of all attempts, but with pediatric patients, 40% of attempts are unsuccessful.1 Advances in healthcare have made it possible to use supraglottic airways on pediatric patients. Many times pediatric patients have less oxygen reserves and the placement takes less than five seconds while allowing for continued compressions following the current CPR guidelines.8
Several studies show that the use of drug intervention improves intubation; however, this practice is not being widely used. It has been shown in the ED to greatly increase successful and atraumatic intubation.4
In the field, only fully unconscious patients are likely to be intubated, while many conscious patients–particularly trauma patients with facial injuries–often need further, more aggressive management.4 Although these patients represent a small number of challenging intubations in the field, there’s support that unresponsive patients will benefit from the use of pharmacology during and after intubation. The Denver study doesn’t encourage the wide use of drug intervention but is still seen as a tool to further increase success rates in the field.1
It’s been taught that rapid airway management in the field is key to a successful patient outcome, but the practice of taking someone who has the ability to manage their own airway and putting them into a situation where they can’t protect that airway has fallen under much controversy. Very few EMS agencies are involved in the practice because of low frequency, the demand for further training, and increased liability to the provider and services practicing the skill.9 In the United States, it’s often only flight crews and critical care paramedics who are using rapid sequence intubation (RSI) as means of airway management.1
Other tools, like continuous positive airway pressure and surgical airways, have made RSI less favorable, and because of the need for an airway following RSI, supraglottic airways with sedation have been seen as an alternative to RSI.9
CONCLUSION
Airway management is viewed by most EMS systems as the No. 1 prehospital patient priority. Because of the increase in litigation and the higher standards coming through the prehospital field, we must reevaluate our practice.
With more research available than ever before, and with the improved ability to track outcomes of patients, every system should tailor its program and procedures to suit its unique needs. In systems that see low numbers of intubations per paramedic, training is vital. Not only is the ability to perform under pressure important, but also that it’s performed correctly. We must also address, monitor and remedy bad habits early and often.
Although providers earn their merit on the ability to intubate a patient, the patient is still the most important part of the equation. New advanced airways are less difficult to place and are consequently better for the patient and should be considered. Supraglottic airways are quick to place by a wide range of responders. They allow for a higher success rate without interrupting or delaying further care or transport.
As rapid sequence intubation has fallen out of favor, many patients can further benefit from pharmacology to assist in intubation rather than in the facilitating of intubation. Studies have found that drug intervention can or should increase successful intubation rates in the field if used properly.
Many tools help to prevent unsuccessful intubations from not being recognized in the field. End tidal CO2 monitoring is now available in almost every cardiac monitor and has become the standard of care. Although these techniques may help verify placement, services must still require their personnel to continually monitor tube placement and airway patency throughout care and transport–and immediately prior to turning their patient over to the receiving hospital staff.
Although we can’t foresee all possible negative outcomes, we have the tools to minimize them as much as possible. The likelihood of misplacing or not recognizing a misplaced airway is greatly reduced by using and practicing with all the tools available.
REFERENCES
1. Denver Metro Airway Study Group. A prospective multicenter evaluation of prehospital airway management performance in a large metropolitan region. Prehosp Emerg Care. 2009;13(3):304—310.
2. Werfel PA. The dark side of airway management: Forensic cases in EMS advanced airway management.EMS World. 2013;42(1):21—26.
3. Sullivan RJ. 10 steps for smarter intubation. EMS World. 2012;41(9):50—54.
4. Valenzuela T, Mosier J, Saakles J. Tunnel vision.JEMS. 2013;38(1):32—37.
5. Grayson SK, Gandy WE. Airway management strategies: Add these six tips to your airway tool bag.EMS World. 2013;42(2):27—30.
6. Allen SR, Conover CG. Difficult airway: Providers treat patient with multiple gunshot wounds. JEMS. 2012;37(6):32—35.
7. Jensen JL, Cheung KW, Tallon JM et al. Comparison of tracheal intubation and alternative airway techniques performed in the prehospital setting by paramedics: A systematic review. CJEM. 2010;12(2):135—140.
8. Tomek S. How to manage the pediatric airway: Training for these critical calls is vitally important. EMS World. 2012;41(1):52—60.
9. Hickman J. Prehospital advanced airway management for trauma in the United Kingdom: How, when and by whom? Trauma. 2006;8(3):169—177.
