Comments on: Dopamine

By: Just a medic

Just a medic — Sat, 13 Mar 2010 21:25:04 +0000

To Chris: Lately I’ve been seeing RoSC every 3rd or 4th code, thanks probably to quick defibrillation by volunteer firefighters. On an unsuccessful code with field termination my agency expends about $130 worth of supplies. On a code with RoSC and transport my agency expends about $250 in supplies. A bag of dobutamine (or alternately dopamine) costs about $6.

To Medicscribe: You’re on the right track with “pseudo PEA.” I like that term. I agree about an organized ECG rhythm plus an increasing EtCO2 strongly suggesting RoSC even if you can’t measure a blood pressure or feel a pulse. Often I have time to set up central venous pressure monitoring while CPR is underway, and this adds a third indicator. The triad of A-waves on CVP plus organized ECG plus rising EtCO2 is unmistakable evidence of RoSC. Vasopressors and standby pacing seem to work well. I’d encourage you to pursue supporting protocols if you don’t have them already.

One of these days I hope to get arterial pressure monitoring going in time to capture the transition to RoSC on the memory card. I concur with your hypothesis: we’d see pressures probably in the 40′s or 50′s at first, well beneath the sensitivity of noninvasive cuffs. This area may be ripe for research. I wonder how much time elapses after true RoSC before we the intubating gorillas take notice?

By: medicscribe

medicscribe — Sat, 13 Mar 2010 14:07:36 +0000

I think there is some merit in getting the dopamine ready. You would of course have to guage your odds of ROSC. If someone is asystole and unwitnessed, you are obviously less likely to need it, but witnessed arrests, arrests with high ETCO2 after intubation are all much more likely to be resucitated.

Where I have thought of giving Dopamine before ROSC is in those patients who show a jump in their ETCO2, but you still can’t feel pulses. These are the psuedo PEA patients. You have a rhythm, and in all likleihood they have a blood pressure, it is just to low for you to feel a pulse. Maybe with a doppler, you could hear one. I think these patients might benefit from Dopamine. I haven’t used it in this situation yet, but I am thinking of discussing it wen we readdress our regional guidelines.

By: Chris

Chris — Thu, 11 Mar 2010 04:32:55 +0000

You must be getting a whole lot more ROSC than we are here. If we set up our pressor drip before getting pulses back, we would never start 12 of every 13 or so of those drips. That’s a lot of wasted effort, and a whole lot of wasted drug.

By: Just a medic

Just a medic — Wed, 10 Mar 2010 18:26:04 +0000

Like medicscribe, I’ve experienced my share of cardiac arrest patients who go RoSC only to crump again a couple minutes later once the epi wears off. A couple years ago a newly minted paramedic taught me something new. He pointed out how long it takes to find the dobutamine (or dopamine), spike the bag, guesstimate a weight, and calculate a drip rate. He suggested I could avoid the crump phase entirely by starting a vasopressor drip “soon enough,” i.e. before the patient *needed* it. The justification was that, by definition, patients in cardiac arrest were experiencing cardiogenic shock. We know cardiogenic shock doesn’t — can’t — resolve instantaneously. I think he was on to something. For the past several dozen codes I’ve been preparing my vasopressor during CPR, going so far as to start an extra peripheral IV and hook up the dobutamine bag (without turning it on). If/when we get RoSC, step 2 is to activate the vasopressor drip with a flick of the thumb. (Step 1 is to activate the transcutaneous pacer and step 3 is to measure a blood pressure.) Since I changed I’ve been seeing less hypotension in my RoSC patients, often avoiding it entirely. That lets me move on to other things like the ventilator, hypothermia, sedation, 12-leads, etc. Let’s face it, when one works as a solo medic every little bit helps. Has anyone else tried this?

By: Foster

Foster — Wed, 10 Mar 2010 14:09:50 +0000

Peter,

Yeah, I spoke with some nurses about this a few weeks ago when I found how difficult it was to set the drip rates within a reasonable amount of time. They all had the same story as you: it takes a good amount of time watching that drip chamber to get even close, and even then often times nurses would do 10 minute check backs and “tape counts” to verify they had set the wheel correctly. Often times, even after spending a lengthy period setting the rate, they found they hadn’t and had to readjust.

I think you’re right about the reduced potential for damage given our short transport times, and the inherent inaccuracy due to a “made up” patient weight, but even still the whole process strikes me as a a little rougher than it should be. For the JEMS Games, I ended up buying a small musician’s electronic metronome, which I could set to beep at a given rate. That helped a lot with setting drip rates on the fly. People will probably make fun of me, but I packed it in my backpack that I bring to work. The guidelines may say “titrate to effect,” but I still think it is reasonable and professional to know more concretely what dose you are giving your patient. I do sometimes wonder if the inaccuracy of our drips often has a lot to do with why nurses lock them off or pull them down so quickly: they can’t chart an unknown titrated rate, so I bet it is easier for them to simply stop the bag and think about restarting it themselves (on a pump) later on.

At that same conference, I dropped by one of the vendor’s booths that sells those mini med pumps and inquired about cost. They’re about four grand each. Heh. I’m not holding out any hope that those will be sitting on our ambulances any time soon.