Emergency Care Essentials: 'The Failed Airway - Tips and Tricks'


Author: Kevin High

In the prehospital arena airway management remains the most important skill and the most challenging. Less than ideal conditions, critically ill/injured patients and at times limited options make airway management extremely taxing. At some in your career you will encounter a failed airway situation. The following text gives you some options to add to your airway repertoire.

Definition:
The failed airway is not the same as a difficult airway. The difficult airway has three dimensions:

  • Difficult to intubate
  • Difficult to ventilate/oxygenate
  • Inability to or difficulty in performing a cricothyrotomy

However, the failed airway is different. The criteria are listed below:

  • Failure to intubate on three attempts by a skilled and experienced provider.
  • A "can't intubate can oxygenate" scenario
  • Any failure at oral intubation with inability to maintain Sa02 >90% using BVM.
  • The 'can't intubate, can't oxygenate" scenario

Studies show that anywhere from 1-10% of patients will present or progress to a failed airway type scenario. In this situation what should you do? What are your options? My personal philosophy tends to lean to the simpler, low tech side of doing things.

Failed Airway Options
Many different devices are currently on the market that can be applied in the failed airway situation. Each has its pros and cons but all require one thing; training. To be proficient with a skill or device you must be properly trained and have repeat instruction from time to time to remain proficient.

The use of devices, gadgets, etc. does not increase your ability; only your options.

The ideal device for the average EMS service would be effective, cheap, and easy to learn. These devices will be rarely used if at all so why not use something that works well, is simple to use, and is easy to learn?

Existing devices on the market include the lighted stylet or light wand, a retrograde intubation kit, several surgical and/or percutaneous crichothyrotomy devices, the laryngeal mask airway and intubating laryngeal mask airway, and the combitube to name a few. Several years ago two devices existed for use in the failed airway scenario. The esophageal gastric tube airway (EGTA) and the esophageal obturator airway (EOA) have been replaced over the years by more efficient devices. A colleague of mine refers to the EOA as the "essentially obsolete airway". All cost money, all require initial and ongoing training and all have varying degrees of success in the failed airway scenario.

In the spirit of simple, fast, low tech and cheap here are some techniques that can be applied quickly and simply in the failed airway scenario.


Personal Airway Algorithm (PAA)

The first technique is not a device or gadget but a plan. Every provider needs a plan for worst case scenarios. In the event of a failed airway you have options. Become familiar with each and preplan every conceivable scenario utilizing those options. Discuss those options with your partner. What happens if we can't intubate or ventilate someone? Where do we keep this or that piece of equipment? Learn and discuss these things prior to encountering a failed airway scenario. No matter what your skill level you have options. Have a PAA that works within your scope of practice and optimizes your skills.


BVM Technique
Once you've recognized you have a failed airway and are not able to adequately bag mask the patient quickly try the following approach. Inability to adequately oxygenate/ventilate with BVM can at times be remedied with a change in technique. The 2-person approach will often work. One provider uses both hands to form a seal and mask hold while lifting the mandible forward (there should be no movement of the patient's head/neck in the face of suspected cervical spine injury). The other provider may ventilate with one hand and give cricoid pressure with the other. Concentrate on ventilation and oxygenation. Observe for good rise and fall of the chest. Nasal airways should be placed in BOTH nares along with a proper fitting oral airway.
Let your initial response to inability to bag mask ventilate a patient be a more aggressive approach. Also don't forget to check obvious things also; i.e. is the oxygen on? Is all equipment functioning properly?

Digital Intubation
Digitally-assisted tracheal intubation may be performed in any patient though it is generally easier in smaller adults and pediatric patients. Placing an endotracheal tube without instrumentation is the ultimate low-tech technique. This procedure is popular amongst tactical and military providers because of its ease and less equipment intensive approach. Patients that are entrapped or in a difficult position, low light situations or patients with disrupted/traumatized anatomy are good candidates for digital intubation. In patients with large amounts of vomitus, blood and/or secretions in their airway this procedure can be a lifesaver. The procedure does have its drawbacks. It can be difficult to perform if the intubator has large hands of if the patient is large. You may use this technique on infants, children or adults. Needless to say the patient must be deeply unconscious!

The technique is as follows. Have someone hold traction on the patient's tongue with a 4 x 4 gauze pad; this should be done gently but firmly. Your endotracheal tube should have a stylet inserted and be bent in a 90-degree angle at the junction of the middle and distal thirds of the tube. Slide your index and long fingers of your nondominant hand palm down along the tongue. You should feel the tip of the epiglottis with the tip of your long finger(to me it feels like the lobe of your ear). Direct the epiglottis anteriorly and insert the tube in the mouth. Use your index finger to direct it into the glottic opening. Confirm placement with conventional means and ventilate.


The Combitube®
The Combitube® is very effective in the "can't intubate, can't oxygenate" scenario. It is easy to insert and can be used by basic providers. The Combitube® appears in one study to be superior to the EGTA and LMA I the prehospital setting and it has been shown to be a useful airway rescue device in the failed airway scenario. A high rate of success with few complications have been reported in prehospital use for cardiac arrest. The Combitube® is mainly limited to the adult population. The patient must be unresponsive with no airway reflexes. The combitube comes in two sizes one for small adults (4-6' tall) and a larger size for adults >6'. The Combitube® is contraindicated in patients with suspected or known upper airway obstruction due to pathology or foreign bodies. It is also contraindicated in patients with caustic ingestion and known esophageal disease.

The Combitube® is a dual lumen; dual cuff airway that can be inserted blindly into the oropharynx and usually enters the esophagus. It has a low volume inflatable distal cuff and a much larger proximal cuff designed to occlude the oro- and nasopharynx.

The tube is inserted in a blind fashion following the natural curve of the airway. The device either enters the trachea or esophagus. If the tube has entered the trachea, ventilation is achieved through the distal lumen as with a standard ETT. More commonly the device enters the esophagus and ventilation is achieved through multiple proximal apertures situated above the distal cuff. In the latter case the proximal and distal cuffs have to be inflated to prevent air from escaping through the esophagus or back out of the oro- and nasopharynx. The provider should ventilate first via the long tube; the presence of air entry into the lungs and absence of gastric sounds by auscultation means that the combitube is in the esophagus. If there are no breath sounds ventilations should be done via the shorter lumen which means that the combitube is in the trachea. The Combitube® is the perfect rescue airway device and is definitely one of the most effective devices on the street today.

Conclusion
The failed airway is every provider's nightmare. Learn to recognize the failed airway scenario quickly and act definitively. Have a personal plan to use in that scenario.

Another nightmare can be multiple amounts of gadgets and devices that are used infrequently and require lots of training and practice. Focus on things that work, that are easy, low tech, and safe to use.

References:

  1. Staudinger T, Tesinsky P, Klappacher G, Brugger S, Rintelen C, Locker G, Weiss K, Frass M. Emergency intubation with the Combitube in two cases of difficult airway management. Eur J Anaesthesiol. 1995 Mar;12(2):189-93.
  2. Woody NC, Direct digital intubatin for neonatal resuscitation J Pediatrics 1968: 73:903
  3. Murphy, MF, Benumof JL Airway Management: Principles and Practice, Mosby 1996
  4. Walls, RM Manual of Emergency Airway Management, Lippincott 2000