Folks have asked for a video to go with Podcast 43 and as always I do what folks ask for.
Online Medical Education on Emergency Department (ED) Critical Care, Trauma, and Resuscitation
Folks have asked for a video to go with Podcast 43 and as always I do what folks ask for.
My favorite supraglottic airway is the Cookgas Air-Q; it was created by an anesthesiologist, Dr. Daniel Cook. He just created a new device that allows the placement of an esophageal blocker through the laryngeal airway. I gave him a call to hear about the new product and in the course of that conversation, he gave me a ton of tips on the placement of laryngeal airways. Part II will specifically discuss the new device.
I was able to cajole Cliff Reid of the amazing blog, resus.me on to the EMCrit program. Cliff is truly a doc after my own heart as you will hear from the cast.
He is currently an EMS physician and Director of Training at the New South Wales Ambulance Service.
Cliff’s blog, resus.me is an incredible collection of timely articles on emergency medicine, ems, critical care and resuscitation.
Cliff mentions the HEMS service in London. This amazing service sends a physician/paramedic team to the scenes of bad traumas by helicopter and response cars. A well done video is available on youtube:
The winner of the Toxicology Handbook is Jenny Mendelson. Yeah!!!
Update: Want more on DSI after you listen to the podcast below. My friend Minh Le Cong interviewed me on DSI on his amazing PHARM Podcast. It is an additional 45 minutes on newest thoughts on DSI.
On to Delayed Sequence Intubation (DSI)
You have a 50 y/o male with bad bilateral pneumonia. BP 108/70, HR 96, RR 28. He is delirious, agitated, and looks sick, sick, sick! Saturation is 70% on a nasal cannula; when you try to place the patient on a non-rebreather (NRB) he just swats your hand away and rips off the mask. It is obvious to everyone in the room that this patient needs intubation, but the question is how are you going to do it?
Your first impulse may be to perform RSI, maybe with some bagging during the paralysis period. This is essentially a gamble. If you have first pass success, you (and your patient) may just luck out, allowing you to get the tube in and start ventilation before critical desaturation and the resultant hemodynamic instability. However, the odds are against you: bagging during RSI predisposes to aspiration, conventional BVM without a PEEP valve is unlikely to raise the saturation in this shunted patient, and if there is any difficulty in first-pass tube placement your patient will be in a very bad place.
Sometimes patients like this one, who desperately require preoxygenation will impede its provision. Hypoxia and hypercapnia can lead to delirium, causing these patients to rip off their NRB or non-invasive ventilation (NIV) masks. This delirium, combined with the low oxygen desaturation on the monitor, often leads to precipitous attempts at intubation without adequate preoxygenation.
Standard RSI consists of the simultaneous administration of a sedative and a paralytic agent and the provision of no ventilations until after endotracheal intubation (1). This sequence can be broken to allow for adequate preoxygenation without risking gastric insufflation or aspiration; we call this method “delayed sequence intubation” (DSI). DSI consists of the administration of specific sedative agents, which do not blunt spontaneous ventilations or airway reflexes; followed by a period of preoxygenation before the administration of a paralytic agent.(2)
Another way to think about DSI is as a procedural sedation, the procedure in this case being effective preoxygenation. After the completion of this procedure, the patient can be paralyzed and intubated. Just like in a procedural sedation, we want our patients to be calm, but still spontaneously breathing and protecting their airway.
The ideal agent for this use is ketamine. This medication will not blunt patient respirations or airway reflexes and provides a dissociative state, allowing the application of preoxygenation. A dose of 1–2 mg/kg by slow intravenous push will produce a calmed patient within ~ 30 seconds. Preoxygenation can then proceed in a safe controlled fashion. This can be accomplished with a NRB, or preferably in a patient exhibiting shunt, by use of a non-invasive mask hooked up to ventilator with a CPAP setting of 5-15 cm H20 (or some of the new masks that don’t require a machine, but more on that soon). After a saturation of > 95% is achieved, the patient is allowed to breathe the high fiO2 oxygen for an additional 2–3 min to achieve adequate denitrogenation. A paralytic is then administered and after the 45–60 second apneic period, the patient can be intubated.
In patients with high blood pressure or tachycardia, the sympathomimetic effects of ketamine may be undesirable. While, these effects can be blunted with small doses of benzodiazepine and perhaps, labetalol (3), a preferable sedation agent is available for these hypertensive or tachycardic patients. Dexmedetomidine is an alpha-2 agonist, which provides sedation with no blunting of respiratory drive or airway reflexes (4-5). A dose of 1 mcg/kg administered over 10 minutes will lead to a sedated patient who will accept preoxygenation after 3-5 minutes in most cases.
Another advantage of DSI is that frequently, after the sedative agent is administered and the patient is placed on non-invasive ventilation, the respiratory parameters improve so dramatically that intubation can be avoided. In these cases, we then allow the sedative to wear off and reassess the patient’s mental status and work of breathing. If we deem that intubation is still necessary at this point, we can proceed with standard RSI by administering a conventional sedation agent (e.g. etomidate or additional ketamine) in combination with a paralytic, as the patient has already been appropriately preoxygenated.
A video demonstrating the above concepts is at: http://emcrit.org/misc/preox/
Darren Braude, Aiway and EMS master from New Mexico demonstrates the use of a bougie to make the cric procedure MUCH easier. For more great Braude magic, see his site at airway911.com.
Here is my video on performing open cricothyrotomy in 3 situations: with a trach set and an assistant, with a trach set when alone, and when you only have a scalpel.
Ok, Ok, I promise this is the last airway episode for at least a little while. I am perhaps a bit obsessed. Had this show in the works for a while. The cric is the last barrier between a failed airway and death. EM docs need to be able to perform this procedure without hesitation. This requires training and practice until you can perform the procedure in < 30 seconds literally with your eyes closed!
Since you need to practice and patients get a wee bit pissed if they wake up with an unnecessary, unexpected tube in their neck, you need something to train on. Pig trachs smell and are not great training IMNSHO. Instead, read this article:
Here is the picture
With this set-up, which costs nothing, you can practice as many times as necessary any time you like. You’ll see my version of the set-up in my video below.
I prefer surgical crics. I think wire-based seldinger kits fail badly when stress is involved. That is opinion. They are also entirely too slow; that is FACT.
Here is a video with the three techniques I prefer for crics
Next we talk to my friend Seth Manoach, another of the ED Intensivist clan. He has a technique for fiberoptic-stylet guided crics.
So after the awake intubation video went up on emrap tv, I got a flurry of emails telling me how cool the concept is, but questioning who this would actually be usable on.
To answer that question, we first must discuss who actually requires intubation. If you wait until the patient is apneic, then of course you can’t use awake intubation. The idea is to intubate before the patient stops breathing.
Crash-a patient who is dead or near dead
Now some of these make sense and some not so much
Here are my reasons to intubate:
Crash-for me this is any apneic patient
Can’t Protect Airway-this one is good, a patient with pooling secretions or obtundation with vomiting buys plastic
Possible Loss of Airway-angioedema, anaphylaxis, neck trauma. These are good reasons to intubate and usually earlier is better and safer.
Oxygenation/Ventilation issues for me mean you intervene. But this doesn’t necessarily mean intubation, if the patient has a reversible problem, put them on Non-invasive instead of intubating. See the podcast.
So it all comes down to the last reason
Expected decline-this should be the reason for many ED intubations. If the patient has O2/CO2 issues and they will be getting worse, then consider intubation.
Supply/Demand Imbalance-Last reason, not discussed as often in the ED is severe metabolic acidosis or shock where the lungs are causing a huge metabolic demand in a patient without much supply.
So who can be intubated awake? Any patient except the crash airway can be intubated awake. If you think they are a difficult airway, temporize with NIV while you topically anesthetize and then do the patient awake while they keep breathing.
Who is a difficult airway, there are few good answers.
THe LEMON rule also coined by the Walls crew is probably as good as any:
Look at head and neck
see here for more
I also discuss a new possible indication for awake intubation
Intubation is a sexy procedure, there is no doubt about it.
NIV does not have the glamour; it’s not nearly as cinematic. But for the patient, to spend 30 minutes on a NIV mask is preferable to a couple of days on the ventilator. In this episode, I discuss some of the basic ideas and methods of NIV.
It is pretty simple as the mode only has 3 main settings:
FiO2 – set based on oxygen requirements, just like on the vent
PEEP/EPAP/CPAP – all the same thing, set this based on OXYGENATION needs. If the patient’s sat is low, start at 5 cm H20 and titrate up to 15-17 as needed.
PSV/IPAP – this setting is for ventilation. If your patient does not have ventilation problems, they don’t need PSV. If they do, start at 5 cm H20 and titrate to 15-17.
Yes, that’s right, I did not tell you to put every patient at 10/5. Very few of your patients will have both ventilatory and oxygenation problems. Asthma and COPD need inspiratory support. APE, atelectasis, pneumonia patients need PEEP.
I also talk about sedation while a patient is on NIV.
Awake intubation can save your butt!
It requires forethought and humility–you must be able to say to yourself, “I am not sure I will be able to successfully intubate this patient.” However, the payoff for this thought process is enormous. You can attempt an intubation on a difficult airway with very few downsides. If you get it, you look like a star, if you don’t you have not made the situation worse.
Two of my critical care resident specialists, Raghu Seethala and Xun Zhong, volunteered to intubate each other awake. The purpose of this was to let them gain experience, understand what their patients would feel during the procedure, and to prove that awake intubation can be done without complicated nerve block injections or fragile equipment, such as a bronchoscope.
Look for this area in the lower right of the screen
Here is the procedure for ED Awake Intubation–EMCrit Style:
If you can give it early 10-15 min before topicalizing, it will be most effective.
Note: the systemic and pulmonary absorption from this method is quite low. The only place to watch out is spraying the trachea. I would not spray more than 2-3 cc down the ol’ windpipe.
That’s all for this week
For more info on awake ED intubation, you can view a complete lecture here
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Hi, my name is Scott Weingart.
I am an ED Intensivist from New York City. My career goal and the purpose of this blog and podcast is to bring Upstairs Care, Downstairs-–that is to bring ICU level care to the ED, so our patients can receive optimum treatment the moment they roll through the door.
Best Medical Weblog of 2010 from the folks at Medgadget.com