REBELCast: The Crashing Asthmatic

01 Jun
June 1, 2015

The Crashing AsthmaticAcute severe asthma, formerly called status asthmaticus, is defined as severe asthma unresponsive to repeated courses of beta-agonist therapy or subcutaneous epinephrine. It is a medical emergency that requires immediate recognition and treatment. Recently, Anand Swaminathan (Twitter: @EMSwami) gave a lecture to the residents at the University of Texas Health Science Center at San Antonio (UTHSCSA) February 2015. This post is a summary of that lecture on how to manage the crashing asthmatic.

 Management of the Crashing Asthmatic

Click here for Direct Download of Podcast

Case: 45 year old male with known past medical history of asthma comes to ED via EMS with chief complaint of difficulty breathing.

Vital Signs: BP 80/57     HR 146     RR 45     O2Sat 91% on room air

EMS has already provided: Beta agonist therapy, Oxygen therapy, and IVF

Summary of Heroic Medical Measures in the Crashing Asthmatic

  1. The initial management in the crashing asthmatic should be breathing, circulation, airway not airway, breathing circulation (i.e. “BCA” not “ABC”).  We want to try and avoid intubation if we can.  Intubation of asthmatic patients was historically associated with increased morbidity/mortality.
  2. Pre-oxygenate your patient with high flow nasal cannula at 20 – 30 LPM (22050948).
  3. IM EpinephrineNext consider using IM Epinephrine 0.3 – 0.5mg of 1:1000 (3354935). Severe asthmatics will have a hard time getting inhaled beta agonists into the small airways, but parenteral epinephrine will get into the circulation and get to where it needs to provide support.
  4. Non-Invasive Positive Pressure Ventilation (NIPPV) can help decrease work of breathing and help push beta agonist into the smaller airways (12684289)(7486361).
  5. Corticosteroids main effect is to help reduce inflammation, but these effects won’t be seen until 4 – 6 hours later.  It is important however to give corticosteroids early because this helps up regulate the beta receptors in the lungs at about an hour after giving the medication.
  6. Give IV magnesium sulfate for its bronchodilator effect, but don’t just give 2g IV x1. Instead give 2g IV and repeat it upto 2 more times over an hour (7781349) (24731521).
  7. Give IVF at a dose of 30cc/kg because patients with acute asthma exacerbations because patients will have insensible losses.  Also if you are going to intubate patients with asthma, once they are intubated due to the positive pressure ventilation they will have a decrease in preload and IVF will help maximize preload.
  8. ketamineSub-dissociative dose IV Ketamine (0.1 mg/kg followed by IV infusion of .5 mg/kg/hour for 3 hours) may be helpful to facilitate use of BiPAP in a hypoxic/combative patient (8629747). If you have gotten to this step you should start setting up for intubation at this point in case the patient continues to deteriorate.
  9. Delayed Sequence Intubation is a procedural sedation to help facilitate pre-oxygenation. (25447559).
  10. Intravenous epinephrine can be considered as well.  In hypotensive patients, it is possible that the IM epinephrine is just not circulating (12712039) (16713785). REMEMBER we want to use the 1:10,000 concentration here and even think about push dose epinephrine.

Push-Dose Pressors

Summary of Intubation in the Crashing Asthmatic

  1. Don’t forget NO DESAT (Nasal Oxygen During Efforts Securing A Tube). This will buy you a longer apneic period while trying to intubate.
  2. RocketamineKetamine 1 – 2 mg/kg IV is the ideal induction agent due to its bronchodilatory effects. Remember you already used a sub-dissociative dose in your medical management so why change to a different agent.
  3. Rocuronium 1.2 mg/kg IV is the ideal paralytic agent as it will keep the patient paralyzed close to 90 minutes which can help with ventilator management.

Summary of Ventilation Management in the Crashing Asthmatic

  1. Permissive Hypercapnia allows for CO2 to rise and pH to drop in order to avoid auto-peep and barotrauma.
    • Respiratory Rate of 6 – 8 breaths/min
    • Tidal Volume of 6cc/kg of IDEAL BODY WEIGHT
    • Peak Flow 90 – 120 L/min
    • All of the above increases the Inspiration/Expiration time to allow patients to not auto-peep
  2. If still having issues be sure to trouble shoot the ventilator.
    • Remember Peak Pressure is the maximum amount of pressure sensed by the ventilator in the ventilator circuit and doesn’t reflect what is going on in the lungs
    • We care about Plateau Pressure which is the pressure in the lower airways.  Shoot for a Plateau Pressure of <30 mmHg. (If you hit the expiratory pause button on the ventilator, this will give you the plateau pressure)
  3. Ventilator Asynchrony occurs due to patients being tachypneic and breathing against the ventilator and start to breath stack and develop more auto-peep.  The solution for this is to keep the patient paralyzed and appropriately sedated. (Remember these patients are on high doses of steroids and critical care myopathy and long term paralysis is a real thing, so don’t keep them paralyzed for more than 2 – 3 hours).
  4. If Plateau pressures are still running high you can consider a couple other things as final ditch efforts:
    1. Inhalational Anesthetics by anesthesiology in the operating room due to their bronchodilatory effects (25662208)
    2. ED ECMOV-V ECMO will help get oxygen into the bloodstream (Checkout edecmo.org)
  5. If the patient is having hemodynamic instability, 1st disconnect them from the ventilator (removes equipment failure from the equation) and forcefully exhale the patient by pushing down on their chest softly (this can take 20 – 30 seconds), finally think about the DOPES mnemonic:
    • Displacement of endotracheal tube
    • Obstruction of endotracheal tube
    • Pneumothorax
    • Equipment Failure
    • Stacked Breaths

REBELCast Show Notes

Bibliography

The following two tabs change content below.

Salim Rezaie

Clinical Associate Professor of EM and IM at University of Texas Health Science Center at San Antonio (UTHSCSA)
Creator & Founder of R.E.B.E.L. EM
Tags: ,
10 replies
  1. Brett Rosen says:

    Also consider some other things too. I call it “throwing the kitchen sink” at them – some of it is not necessarily truly evidence but if it’s not dangerous, I’d rather say I tried everything before intubating.

    I REALLY like SQ terbutaline and I like giving it very early. As you said, it gets into the smaller airways before any inhaled beta agonist can. I also start with 4gm of Magnesium, not 2gm – it’s pretty hard to get someone hypermagnesemic and the possible benefits outweigh the risks. Something else I have seen work is Heliox – if I can recall, there was a couple studies showing no true benefit but I know of 2 chronic asthmatics who I’d see every few months in training that the only thing that seemed to ever work was Heliox so we got it quickly on these 2 folks when they showed up.

    Reply
    • Salim Rezaie says:

      Hello Brett,
      As always thank you for reading, listening and leaving a comment. I like SQ terbutaline as well…its old school but is a true beta agonist. The only issue I have with this medication, is that it is not readily available in all EDs. In other words you have to wait for it to come down from pharmacy and in a patient who is already in extremis, you may not have time to wait.
      As for IV magnesium. I agree that 4mg vs 2mg IV is hard to make a patient hypermagnesemic, but remember if the patient is already volume depleted and borderline hypotensive, magnesium could drop blood pressure even more. If there are no BP issues, then sure have at it. 4mg IV STAT!!!!
      Heliox can work to help increase laminar flow, but if you have a patient who is already hypoxic, it only comes in a 70/30 and 80/20 mix. It is hard to oxygenate them with only the equivalent of room air (i.e. 20% O2) or even just a step up from that (i.e. 30% O2). And also again, most EDs don’t have heliox setups in their EDs and have to call respiratory therapy to get this. By that time, “the kitchen sink” has worked, or you are already looking to get a definitive airway.
      All your thoughts are great, and we shouldn’t forget about these other modalities, but it is important to remember logisitics too. Where are the meds coming from? How long will it take to get them? etc….Thanks again Brett

      Salim

      Reply
  2. Corey says:

    First of all I would like to say I really enjoyed this podcast, being a RT this is of course of great interest to me. I actually was happy it just came out as I had some RT students today and was able to share this with them as well during their clinical rotation.
    I did notice that there was a minor correction, to receive plateau pressures you use the inspiratory hold not the expiratory hold on the vent.
    I want to thank you all for putting out all of these podcasts and blogs. I know it must take lots of time and effort but I believe not only is it a huge benefit to any provider it’s touching lives.

    Reply
    • Salim Rezaie says:

      Hello Corey,
      TY for listening and sharing with your students. Also you are correct it is the inspiratory hold and that would make more sense. TY for catching this. Always feel free to write comments on here about anything that needs to be corrected. We really do love the post-publication peer review. We appreciate your support and always feel free to leave comments on the blog for us.

      Salim

      Reply
  3. ash says:

    In my experience when faced with a crashing asthmatic, the first thing I look for is 20ml of 10mcg/ml Adrenaline and Stand face to face with the patient and keep eye contact and reassure, while others do all the other preparations. I also tend to let them decide on what posture they are comfortable with and treat them in that position which quite often is sitting on the trolley with legs swung over.

    The less experienced clinicians possibly delay or do not employ IV adrenaline, is what I have observed. I have to say I still use aminophylline as well, as part of the kitchen sink.

    Had 3 such cases recently 2 we were able to avoid intubation in. The third improved enough over an hour to avoid intubation, but was later intubated in ICU, possibly because of the lowered dose of IV adrenaline led to deterioration. The anxiety and feeling of near doom is severe in these patients [anybody who has had this while scuba diving will know] and the patients have always said to me that my standing face to face with them and continuously talking to them made a big difference. Get them to concentrate on you and concentrate on their breathing and not listen to everything else that is going on in that noisy resus bay, where lots of things are being said.

    Reply

Trackbacks & Pingbacks

  1. […] post is meant to accompany the REBEL Cast episode on The Crashing Asthmatic from June 2015. This blog post will also be simultaneously posted on the Core EM site here. Come […]

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply

Your email address will not be published. Required fields are marked *

Time limit is exhausted. Please reload CAPTCHA.

Optimization WordPress Plugins & Solutions by W3 EDGE