EMCrit Podcast 40 – Delayed Sequence Intubation (DSI)

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.

Here is the reference for the incredible guidelines on ketamine in the ED.

On to Delayed Sequence Intubation (DSI)

The Case

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.

A Better Way

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/

A version of this article originally appeared in ACEP News.
1. Walls RM, Murphy MF. Manual of emergency airway management, 3rd edn. Philadelphia, PA: Lippincott Williams & Wilkins; 2008.
2. Weingart SD. Preoxygenation, reoxygenation, and delayed sequence intubation in the emergency department. J Emerg Med2010 Apr 7. [Epub ahead of print]
3. Aroni F, Iacovidou N, Dontas I, Pourzitaki C, Xanthos T. Pharmacological aspects and potential new clinical applications of ketamine: reevaluation of an old drug. J Clin Pharmacol 2009;49:957–64.
4. Carollo DS, Nossaman BD, Ramadhyani U. Dexmedetomidine: a review of clinical applications. Curr Opin Anaesthesiol 2008;21:457–61.
5. Abdelmalak B, Makary L, Hoban J, Doyle DJ. Dexmedetomidine as sole sedative for awake intubation in management of the critical airway. J Clin Anesth 2007;19:370–3.
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EMCrit Podcast 29 – Procedural Sedation, Part II

It seems the government and other specialties are trying hard to make sedation as difficult as possible in the ED. We must persevere to provide the best procedural sedation to allow maximal comfort and safety for our patients. This continues the discussion started in Part I, where we discussed etomidate, ketamine, and versed/fentanyl. In this podcast, I discuss propofol, ketofol, and dexmedetomidine.

the emcrit procedural sedation chapter has tons of references for all of this

Propofol

great propofol articles:

Ann Emerg Med 2008;52:392-398
Ann Emerg Med. 2007;50:182-187

Start with fentanyl 1-1.5 mcg/kg

Then give propofol 0.5-1 mg/kg

may need additional injections of 0.5 mg/kg

When patient is where you want them, begin the procedure

May need to give additional 20-30 mgs if the patient becomes too light

Burns on injection, you can precede with 20-40 mg of lidocaine to numb the vessels

Ketofol

read more here: (Ann Emerg Med. 2007;49:23-30)

1:1 mix of ketamine and propofol

In 20 ml syringe, place 10 ml of propofol (10 mg/ml)

And 10 ml of ketamine at a concentration of 10 mg/ml

Note: your ketamine may come in a different concentration, if so dilute down to 10 ml of 10 mg/ml

Shake like a martini

Dexmedetomidine

Precede with fentanyl 1 mcg/kg

Start with 0.5-1 mcg/kg over 10 minutes for loading dose

then use an infusion 0f 0.2-1 mcg/kg/hr

Beware in the bradycardic, hypotensive or patients with heart blocks

May need to supplement with 1-2 mg of midazolam

Procedural Sedation Checklist

here it is

Stay tuned for part III coming to you some time in the future.

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Procedural Sedation, Part I (Audio Only)

The audio only version of Part I of the sedation talk.

Remember to check out Part II next…

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Procedural Sedation – Part I

It seems the government and other specialties are trying hard to make sedation as difficult as possible in the ED. We must persevere to provide the best procedural sedation for the maximal comfort and safety for our patients. This brief lecture was originally posted on the defunct EMCrit Lecture Site on 8/7/2009.

I’m reposting it here so I can post part II sometime this week.

This episode, Part I, covers general concepts on sedation as well as ketamine and etomidate/fentanyl.

Part II will cover propofol, ketofol, and dexmedetomidine.

Part III, to be done some time in the future, will cover really difficult sedations.

My friend Reub Strayer has a great PSA checklist as well

 

 

 

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EMCrit Podcast 19 – Non-Invasive Ventilation

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.

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EMCrit Podcast 18 – The Infamous Awake Intubation Video

This post marks the return of the Awake Intubation Video. If you’ve seen it, we will have a brand new post early next week. If you haven’t, well you are in for a treat:

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.

Click Here to Download the Video

Look for this area in the lower right of the screen

Here is the procedure for ED Awake Intubation–EMCrit Style:

DRY THEM OUT & PRETREAT GAG(Do All)

If you can give it early 10-15 min before topicalizing, it will be most effective.

  • Glycopyrolate: 0.2 mg IVP (No central effects – does not cross BBB. You can use atropine, but more side effects are possible)
  • Suction and then pad mouth dry with gauze – you want the mouth very dry!
  • Adminster Odansetron 4mg IV to blunt the gag-reflex

TOPICALIZE (Do All)

  • 5 cc of 4% lidocaine nebulized @ 5 liters per min
  • Gargle with viscous lidocaine (4% best, 2% ok). Place a blob (~3 cc) on a tongue depressor, put it in the back of the throat and have the patient gargle and then spit
  • Spray the epiglottis, cords, and trachea with 4% lidocaine (3 cc) in a Mucosal Atomizer Device (MAD). The patient will cough during this spraying, wear eye/face protection
  • Have another syringe loaded with 4% lidocaine to spray with during the procedure

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.

SEDATE (Choose one!)

  • Ketamine and propofol in the same syringe makes Ketofol. The classic mix is 50 mg of ketamine to make 5 cc and 50 mg of propofol to make 5 cc. Put these both in a 10 cc syringe and shake. Depending on the patient’s hemodynamics, I sometimes will use more ketamine (75% instead of 50%). Give 1-2 cc every minute until you have the patient relaxed, but still breathing and arousable.
  • Ketamine alone also works just fine. Start with 20 mg and give 10 mg every minute or so.
  • If you have it, Dexmedetomidine also works very well as long as your patient is not bradycardic.
  • If you have neither of these 2 mg of midazolam will do just fine.
  • Preoxygenate with NRB

  • Optimally position (ear to sternal notch) with the head tilted all the way back

  • Restrain both arms with soft restraints to prevent the “grabbies”

  • Switch to nasal cannula

  • INTUBATE with Fiberoptic laryngoscope and bougie

  • If the patient coughs or is uncomfortable after placing the bougie through the cords, push more med from the ketofol syringe.

  • Thread  the tube over the bougie with the laryngoscope still in the mouth

  • Confirm tube placement

That’s all for this week

For more info on awake ED intubation, you can view a complete lecture here

Thanks to Raghu and Xun for risking their singing careers and to Jimmy & Anita for technical support. *
The opinions on this site and in the video represent the author’s and not the opinions or policies of the Mount Sinai School of Medicine or Elmhurst Hospital Center. It is not my intention to provide specific medical advice for any individual patient. Please confirm anything on this video with your own clinical judgment and the policies and procedures of your institution. This video is for education purposes only; it does not represent a standard of care or clinical advice.

EMCrit Podcast 15 – the Severe Asthmatic

Don’t intubate the severe asthmatic,

try NIV first

continue the nebs on the NIV

obviously they need steroids and throw in Mag

does ketamine work? maybe…

If you intubate, Ron Walls says add lidocaine to your sedative and paralytic

if you put them on the vent make sure your plateau pressure stays below 30 cm H20

or make sure the flow graph shows flow has stopped before the next breath

flowto0

Here is the vent lecture:

Not the Greatest Vent Lecture Ever

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Video for the Laryngoscope as a Murder Weapon Lecture