The double setup is an airway management strategy conventionally carried out in the operating room, in a stable or relatively stable patient who requires a definitive airway but is anticipated to be very difficult to intubate orally. An otolaryngologist or other surgeon fully prepares to perform a cricothyrotomy or tracheotomy–patient prepped, all equipment laid out, sterile gown and gloved, scalpel in hand–and then gives the anesthesiologist the nod, at which point the patient is induced and orotracheal intubation is attempted. If unsuccessful, anesthesia nods to surgery, who proceeds with a neck incision.
Emergency physicians are trained to manage difficult oral airways and perform cricothyrotomy–how does the double setup apply to our environment? Once the decision to intubate has been made and preoxygenation has been initiated (don’t forget the nasal cannula), ask two questions: How urgently must this patient be intubated? How difficult do I predict this airway to be?
Scenario 1: Must intubate immediately, very scary airway.
Some patients need to be intubated right now, and some patients who need to be intubated right now also are predicted to have difficult airways. The paradigmatic examples of this stressful situation are the dynamic airway insults: patients with bullets, bites or burns (neck trauma, anaphylaxis, airway burn or caustic exposure) who are already showing signs of airway embarrassment. The proper mentality in these cases is this patient is going to require cricothyrotomy, but I’m going to attempt orotracheal intubation, just to make sure. There is no time for a fancy airway assessment or fancy preparations, these patients are a test of your department’s, and your own, usual state of readiness. Patients with dynamic airways should be induced and paralyzed, because intubation will get harder with each passing minute–RSI gives you optimal conditions, as quickly as possible. Once the tools you need to perform cricothyrotomy are at the bedside, use the orotracheal technique that, in your hands, will give you your best shot at first pass success, as quickly as possible. Video laryngoscopy is a good choice. As soon as your first pass fails and not one second later, attempt ventilation (I suggest you move straight to an LMA), but you have accepted that there is a good chance that this is also unlikely to succeed and that the next step is to cut the neck. You must give yourself permission to initiate a surgical airway early in this group. An unsuccessful cricothyrotomy performed at the right time is defensible; a successful cricothyrotomy performed too late is indefensible. Both lead to terrible outcomes, one is defensible, one indefensible. Scenario 1 is an anesthesiologist’s technique compressed into an emergency physician’s timeline.
Scenario 2: Must intubate immediately, no difficult airway features.
Lots of ED patients fall into this category, perhaps the most typical is the CNS catastrophe who presents with a GCS that can be counted on one hand. Like scenario 1, the airway attempt must proceed without extensive preparation, but both orotracheal intubation and ventilation are more likely to be successful, and this procedural reserve affords you a more measured approach. Be mindful, however, that your brief airway assessment may mislead you, and that you never know what you’re going to get when you put in the laryngoscope. You therefore have decided, before you push drugs and put in the laryngoscope, what you will do when laryngoscopy fails, and what you will do when ventilation fails, and you have the materials at the bedside to do it. Experienced emergency providers recognize procedural reserve as a luxury that the patient can revoke immediately and unpredictably, and are thus ready to transition to a scenario 1 type approach every time they push a paralytic.
Scenario 3: No urgency to intubate, very scary airway.
When you have time to intubate, you are swimming in the anesthesiologist’s ocean and you need to use a different stroke; in fact swimming like an anesthesiologist is mostly about wearing several life jackets and surrounding yourself with lifeguards. This scenario might involve a patient with a fixed flexion deformity of the cervical spine who is slowly decompensating from a pneumonia, or a patient with an airway tumor who just took 20 long-acting diltiazem tablets and needs gastric lavage. Calling an anesthesiologist is reasonable in these cases and certainly is the right answer on an oral board exam, but an anesthesiologist may not be available (and certainly will not be available on the boards).
The approach for these patients centers on being cognitively and materially ready for plan A, B, C, and D and on awake technique. It’s also nice to have a few friends at the bedside. Exactly what is plan A-D is up to you, as long as these plans are carefully prepared, and one of them is cricothyrotomy, if the patient cannot be intubated or ventilated. This picture demonstrates an example plan A, B, C, and D and a variety of best practice points.
The patient has a variety of congenital cognitive and anatomic anomalies, was very uncooperative and required intubation for emergent MRI. He is known to be a very difficult laryngoscopy. Our plan was to use an awake technique using IM ketamine sedation to augment local anesthesia.
1. Plan A is video laryngoscopy. The intubator (in the middle) made his best attempt but could not visualize the vocal cords, so without removing the device, handed off the video laryngoscope to the assistant on the patient’s left, who was already performing suction.
2. Plan B is flexible endoscopy, which is ongoing. Note that the operators are at this point using both video screens (video laryngoscope and flexible endoscope) simultaneously.
3. The second assistant on the patient’s right has access to the equipment tray and is also the designated surgical airway operator.
4. The neck is marked, and the site has been infiltrated with lidocaine and epinephrine. The more likely is cricothyrotomy, and the more time you have to prepare, the more advanced your surgical airway preparation should be.
5. The second assistant is using his finger to pull on the right corner of the mouth. This under-utilized technique really opens things up.
6. The usual suction (in this case, the second suction) under the patient’s right shoulder is available to either the intubator or second assistant. The flexible endoscope used in this case does not have suction capability, which made the need for suction on either side more likely.
7. The head of the bed is at 30 degrees.
8. The bag-mask is on the patient’s abdomen. A common mistake is to leave the bag-mask behind the operators, hanging off the oxygen tubing, so that as the saturation is dropping, someone who is already freaking out and tangled in wires and tubes has to perform a complex dance move to get at the device.
9. The intubating LMA is ready to be inserted if emergency ventilation is required. This is our Plan C. Plan D is cricothyrotomy (either carefully if Plans A/B/C have failed but oxygenation is adequate, or quickly at any moment if intubation and oxygenation fail).
10. A variety of tubes and blades, as well as oral and nasal airways.
11. The medications and tools we used to anesthetize the airway.
12. Post-intubation equipment.
13. The ventilator is on standby, connected to end-tidal CO2 (not visible) and programmed with patient-appropriate settings.
14. This container holds our supply of bougies and is sadly empty. There is a bougie on a stand behind the video laryngoscope, not visible but easily accessible to the assistant on the patient’s left.
15. Don’t forget to use a checklist.
Scenario 4: No urgency to intubate, no difficult airway features.
Here we’re talking about the slowly worsening guillain-barré patient, or the patient with the small subdural that the receiving hospital has asked you to intubate for transport. Seems like low risk, and it is low risk, for the patient. But these cases are actually higher risk for you, because when a patient arrives in extremis, your hand is forced and if it doesn’t go well, it’s harder to hold you responsible. In a well patient with normal anatomy who needs to be intubated, you are again in anesthesiologist territory, and you are potentially held to the higher standard of an anesthesiologist, who gets called into the chief’s office when the patient wakes up with a chipped tooth. These are great cases to practice your awake technique; you might find that you don’t mind swimming with a life jacket every once in a while.