The Theorem of Early STEMI Notification

I have been doing a lot of thinking about STEMI. I deal with it on the street as a paramedic and I deal with it at the hospital as an EMS Coordinator and member of our hospital’s door-to-balloon committee. Here is the progression I have seen over the last twenty years when it comes to STEMI Care:

1. Put patient on 3 lead monitor, IV, 02, ASA, NTG and Morphine
2. Do a 12-lead, in addition to the above. If it shows ST elevation tell nurse on arrival at hospital or find Dr and show him 12-lead.
3. If patient has inferior MI, do right sided 12-lead and withhold nitro if RVI
4. Mention STEMI on radio patch, and hope nurse tells doctor
5. Call in STEMI ALert and Ask to speak to Dr.
6. Use Fentanyl instead of Morphine.
6. Give 02 only if hypoxemic
7. Apply 12-lead immediately on patient contact, and if it shows STEMI, call in STEMI alert ASAP, ideally within 5 minutes of patient contact.

It is this last element involving Early Notification I want to talk about today. How much notification does a hospital need? For many years nearly every notification was a “we’re 2-3 out with a patient with etc. etc. etc, and I have done IV, 02, monitor, etc. etc. etc.”

Paramedics were uncomfortable patching in before they had done all their treatment. Why? Habit and perhaps because they didn’t want the doctor or nurse to say, how come no ASA? Or do you have an IV? We are telling them now we would like to hear a patch that says, “Hello, medical control. I have a STEMI Alert and am requesting cath lab activation. I’m on scene with a 50 year old male, cool and clammy with severe chest pain, father died at 49 of an MI. 12-lead shows 2 millimeters elevation in II, III, and avF with reciprocal change in I and avL I’ll get back to you with more once we’re transporting. Current ETA is 30 minutes.”

30 minutes. Is 30 minutes too much notification? In some cases, maybe. In others, typically on nights and weekends, it is probably just right.

Albert Einstein and Sir Issac Newton look out, but I have developed my own mathematical formula to determine how much notification is needed.

Early notification must be > or = to the amount of time it takes the cath lab to be ready to accept the patient to achieve optimal benefit.

Any less time is potential lost minutes, lost heart muscle.

How long does it take a cath lab to be ready? It depends. I did a back of the envelope study which showed an average time of 15 minutes, but with a range from one to 40. Most PCI centers have call-in teams for the evening and weekend hours who must be ready within 30 minutes. Sometimes during the week, even when the team is present, the cath lab tables are being used by elective patients. A 30 minute heads up on an incoming STEMI can mean an available table when the patient gets there that might not otherwise have been kept open.

In the ideal world of early notification, the cath lab is always ready when EMS arrives so that the patient can go right to the cath lab on the EMS stretcher.

Let’s do some math.

Let’s say on this day, it will take the cath lab 20 minutes to be ready.

EMS calls from 20 minutes out. Heart muscle saved = 20 minutes.
EMS calls from 15 minutes out. Heart muscle saved = 15 minutes
EMS calls from 10 minutes out. Heart muscle saves = 10 minutes.
EMS calls from 5 minutes out. Heart muscle saved = 5 minutes.

Now, I could complicate the formula by adding a plus time for time in ED(beyond mere waiting time). I believe that by its nature, transferring a patient to an ED bed, to an ED nurse, etc, adds a time tax that may add 5 minutes or more than if the patient had stayed on the EMS stretcher.

EMS calls from 20 minutes out. Heart muscle saved = 20 minutes.
EMS calls from 15 minutes out. Add 5 minute ED tax. Heart muscle saved = 10 minutes
EMS calls from 10 minutes out. Add 5 minute ED tax. Heart muscle saved = 5 minutes.
EMS calls from 5 minutes out. Add 5 minute ED tax. Heart muscle saved = 0 minutes.

The bottom line is if you call in 20 minutes out versus 10 minutes out, in this case, you are directly saving the patient 15 minutes of heart muscle.

EMS is the dispatcher for the cath lab. The patient with a STEMI needs the cath lab in the same way a patient in ventricular fibrillation needs a defibrillator or a patient in anaphylaxis needs epinephrine or a patient in penetrating trauma needs a surgeon. Yes, there are treatments you can do to help the patient, but unless he is in v-fib himself, none are more important than activating the cath lab. The quickest way to get the patient to the cath lab is to see that the cath lab is ready by the time the patient hits the hospital. In the ideal world, all stable STEMI patients (those with patent airways and normotensive vitals) could then bypass the ED and go right to the cath lab on EMS stretchers.

So remember:

Early notification must be > or = to the amount of time it takes the cath lab to be ready to accept the patient to achieve optimal benefit.

Greet ACS patient
Acquire a 12-lead
Unless patient goes into vfib (shock!), activate the cath lab
Proceed with treatment/transport

5.

4 Comments

  • Christopher says:

    Excellent points! We’re moving to earlier notifications for everything, even stubbed toes. I’ve anecdotally noticed 5-10 minutes in savings from beds being assigned earlier.

    As for, “[u]nless patient goes into vfib (shock!), activate the cath lab.” Still activate the cath lab! Let them deactivate themselves or the ED MD cancel them, but they really should be there upon your arrival.

    • medicscribe says:

      I should have been more clear here. What I meant was the only thing that should prevent you from immediately activating the cath lab is the need to push the shock button. Once you have pressed the button and shocked the patient, then you can give a heads up to the cath lab. If we have a known STEMI that goes into cardiac arrest, we will likely give a heads up that we are coming in with a STEMI. In our hospital, we once took a patient up to the cath lab while still doing CPR. If the patient is in refractory vfib, the cath lab may be the only hope. If a patient is in vfib in the field, but we don’t have a 12-lead showing the STEMI, we would not activate the cath lab until after ROSC, and then only if the 12-lead showed a STEMI. But in the hospital, it is becomming more common lately for patients with ROSC to go to the cath lab even if their 12-lead does not show a STEMI, if the doctors suspect a cardiac cause of the arrest.

  • Jason says:

    So I read something interesting a while back and unfortunately I’m not going to be able to site a source but it said this. A door to ballon time (d2b) of < 90 mins was immensely beneficial in decreasing m&m in STEMI pt's. We all know that now. It said a d2b < 75 mins added a little more benefit in reducing m&m. But I think at about d2b of about 60 mins we start to approach the limit. That is in decreasing d2b below 60 mins we realize no additional benefit.
    Can anyone site the study?

  • Jake says:

    As for, “[u]nless patient goes into vfib (shock!), activate the cath lab.” Still activate the cath lab!”

    I disagree, but only partially. Assuming by “vfib” we’re talking pulseless, then I would wait until getting ROSC before specifically activating the cath lab.

    *But* that is based on my squad’s practices: 1) codes are generally worked on-scene until either ROSC or termination; 2) while working a code, we normally contact our hospital with a “heads up”, especially when it’s a witnessed arrest. I would certainly include the STEMI information in that but I would let the ER make the decision on whether to activate the cath lab or not.

    Of course, the window where this could happen is also pretty narrow – we usually will call the STEMI alert within a minute or two of getting a STEMI positive 12-lead.

Leave a Reply

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

background image Blogger Img

Peter Canning

JEMS Talk: Google Hangout

Recent Posts
ECG Quiz May 7, 2015
copy-medicscribeheader.png Intranasal Medication April 26, 2015
SW_Rectangle The Jug March 26, 2015
SW_Rectangle The Ideal Medic March 24, 2015
Categories
  • ems-health-safety (7)
  • ems-topics (705)
  • hazmat (1)
  • Uncategorized (421)
  • Archives
  • May 2015
  • April 2015
  • March 2015
  • February 2015
  • January 2015
  • December 2014
  • October 2014
  • September 2014
  • May 2014
  • March 2014
  • February 2014
  • January 2014
  • December 2013
  • November 2013
  • October 2013
  • September 2013
  • August 2013
  • July 2013
  • June 2013
  • May 2013
  • April 2013
  • March 2013
  • February 2013
  • January 2013
  • December 2012
  • November 2012
  • October 2012
  • September 2012
  • August 2012
  • July 2012
  • June 2012
  • May 2012
  • April 2012
  • March 2012
  • February 2012
  • January 2012
  • December 2011
  • November 2011
  • October 2011
  • September 2011
  • August 2011
  • June 2011
  • May 2011
  • April 2011
  • March 2011
  • February 2011
  • January 2011
  • December 2010
  • November 2010
  • October 2010
  • September 2010
  • August 2010
  • July 2010
  • June 2010
  • May 2010
  • April 2010
  • March 2010
  • February 2010
  • January 2010
  • December 2009
  • November 2009
  • October 2009
  • September 2009
  • June 2009
  • May 2009
  • April 2009
  • March 2009
  • February 2009
  • January 2009
  • December 2008
  • November 2008
  • October 2008
  • September 2008
  • August 2008
  • July 2008
  • June 2008
  • May 2008
  • April 2008
  • March 2008
  • February 2008
  • January 2008
  • December 2007
  • November 2007
  • October 2007
  • September 2007
  • August 2007
  • July 2007
  • June 2007
  • May 2007
  • April 2007
  • March 2007
  • February 2007
  • January 2007
  • December 2006
  • November 2006
  • October 2006
  • September 2006
  • August 2006
  • July 2006
  • June 2006
  • May 2006
  • April 2006
  • March 2006
  • February 2006
  • January 2006
  • December 2005
  • November 2005
  • October 2005
  • September 2005
  • August 2005
  • July 2005
  • June 2005
  • May 2005
  • April 2005
  • March 2005
  • February 2005
  • January 2005
  • December 2004
  • November 2004
  • October 2004
  • September 2004
  • August 2004
  • Comments
    Casey
    Intranasal Medication
    Agreed Steve. Love IN Versed for combative/ictal patients. Also IN versed is used in ED for kids. Helps with pain relief and as an amnesic and wears off fairly quick- not sure that directly applies to prehospital but food for thought nonetheless
    2015-05-07 00:36:28
    Chris
    AHA 2015 Guidelines: A Preview
    I am a 25 year veteran firefighter/medic, and 9 year veteran critial care fixed wing medic. I work in Northeast Ohio. In this region, we have all but abandoned endotrachal intubation for the intent of ease of a superglottic airway. AHA de-emphasizing ETI and we have seen this coming for a while. We either bag…
    2015-05-05 20:54:08
    Steve
    Intranasal Medication
    "either because they are seizing or are violent, then the better and quicker route would be IM. " I'm quite hesitant about bring a needle against someone fighting me or shaking... those are the perfect times to be needleless.
    2015-04-27 18:34:14
    bill
    The Ideal Medic
    very well put! aggression can be a good in moderation but over aggression can do harm. 1 year to 30 years no medic will know it all epically with our ever changing job description. thank you for your input!
    2015-04-26 11:46:50
    Ben Leighton
    Adenosine
    Hi. Im a UK Student Paramedic and I have a few questions regarding adenosine (we currently dont carry it) and I was wondering if any of you guys could e-mail me at ben-leighton@hotmail.co.uk and start some correspondance. Im aiming to set a proposal to my service in order to carry this drug and wanted some…
    2015-04-20 13:36:03

    Now Available: Mortal Men

    Mortal Men is available as an electronic book for Kindle, Nook or any other e-reader. Here is a link to some of the places to buy it. The book sells for $3.99. Barnes and Noble Amazon Smashwords Scribd Also Available from iBooks

    Order My Books

    Support EMS Bloggers, Buy Their Books

    Google

    Order Books and Movies

    FireEMS Blogs eNewsletter

    Sign-up to receive our free monthly eNewsletter

    LATEST EMS NEWS

    HOT FORUM DISCUSSIONS