Epinephrine and Amiodarone – Cardiovascular Emergencies & Shock | Lecturio

[Music] so just to break down a couple of these interventions a little bit more epinephrine is a vasoconstrictor that's why we use it in cardiac arrest as you probably remember from pharmacology it's a non-selective adrenergic drug meaning it acts on the alpha and beta adrenergic receptors all equally the great thing about epinephrine is it increases systemic vascular resistance so it clamps down all the blood vessels below the diaphragm and it cuts off blood flow to organs we don't care about in cardiac arrest like the liver and the kidney what we care about in cardiac arrest is the heart itself and the brain because those are the two organs that are going to determine our ultimate outcome in the setting of arrest unfortunately even though it makes a lot of sense to give a medication that would optimize cardiac and cerebral blood flow there's not really great scientific evidence supporting the use of epinephrine and we'll talk a little bit more about what there is so there's only one randomized controlled trial on epinephrine that's ever been done in the history of medicine and it was just done a year or two ago by a group down in Australia and basically what they found is that when epinephrine was given in place of placebo for patients with out of hospital cardiac arrest these patients were much more likely to survive the resuscitation itself or to get a pulse back during the resuscitation and they were much more likely to survive their hospital transport and actually get admitted to the hospital so they would live through their ambulance ride live through their time in the IDI and make it up into an ICU setting unfortunately there is no evidence that the group that received epinephrine was more likely to survive to hospital discharge so while their short-term outcomes were a lot better their long-term outcomes were comparable one of the reasons for this is that unfortunately the sample size of the study ended up being smaller than the investigators intended and they weren't able to demonstrate a less likely outcome like survival to hospital discharge because they just didn't have the sample size to do it so the bottom line is we still don't really know if epinephrine changes long-term outcomes in cardiac arrests and if it makes you many more likely to survive to the end of your hospitalization or to survive with a neurologically good outcome now Abby's a bit of a double-edged sword so on the pro side for epi we know that it increases vascular tone optimizes perfusion of the heart in the brain and it improves short-term survival which clearly is an absolute prerequisite for long-term survival so it seems like it would be a pretty good idea however remember what I told you causes cardiac arrest it's mostly myocardial infarctions and other forms of ischemic coronary disease so when you give epi what does it do to the heart it increases rate it increases contractility and ultimately it increases myocardial oxygen demand which can worsen ischemia epi also does reduce reduce perfusion to other organs which is problematic and we don't know what effect if any it has on long-term survival it might do no good it might even be harmful in the long run we truly don't know so hopefully we'll get more scientific evidence regarding up a nephron as time goes on but for right now experts in the field believe that the pros outweigh the cons and generally it's considered the standard of care and cardiac arrest so according to current protocols epi is a mandatory intervention you give one milligram of it in one to 10,000 dilutions every three to five minutes throughout the cardiac arrest now there aren't many drug doses you need to know cold but this is one that you really should know both for your exams and for your life one milligram of epi one to 10,000 formulation repeated every three to five minutes throughout the cardiac arrest the other drug that was mentioned in our arrest algorithm is amiodarone a mio as you may know is a class three anti-arrhythmic drug and it is indicated for all cases of shock refractory v-fib and v-tach but the current Heart Association guidelines don't say you definitely should give this drug because it's awesome and saves lives they say you can think about it so it's not actually a mandatory intervention and that's because there are two large-scale studies of amiodarone that have shown evidence of short-term survival compared to placebo however there's no evidence that amiodarone is superior to other antiarrhythmics such as lidocaine which was traditionally used in cardiac arrest and there's no evidence that it offers any benefit whatsoever for long-term survival outcomes that means that your patients will have had their cardiac arrests detected quickly they will have received rapid CPR that's high in quality they will have had their rhythm detected quickly and how to shock administered so they've got a pretty good chance of intact survival if we can just get their heart restarted contrast into patients we see in the IDI who arrests at home or out in public places who may or may not have a witnessed arrest who may or may not receive rapid CPR and rapid defibrillation these patients often have a much higher degree of cerebral injury a much higher degree of cardiac injury from their cardiac arrest event and they're less likely to benefit from amiodarone so we have to be a little bit circumspect in whether or not we're going to use it in this population of patients so the bottom line with amiodarone is it's used very commonly for refractory v-fib and v-tach that's not responsive to epinephrine and electricity the dose is 300 milligrams which is double the normal loading dose you would use for other indications and you really should think about it in cases where you suspect that the patient might have a positive outcome if you can reorganize their cardiac rhythm but may be not useful to give it in patients who are likely to have severe cerebral anoxia and go on to have a bad outcome no matter what you do so let's review the algorithm one more time we're gonna call for help and we're gonna start CPR as quickly as we can we're gonna go ahead and perform defibrillation and fortunately for us we're very likely to be able to get our hands on a defibrillator out in public because they've become so readily available in public settings if the patient's in v-fib or v-tach we're going to shock them after the first shock we're gonna perform five cycles of CPR or two minutes by the clock at which point we're going to give one milligram of F Efrain after giving up a nephron we're gonna again resume CPR for five cycles or two full minutes at which point once again we'll recheck the rhythm if it's still shockable we'll perform another defibrillation and then we will consider the use of amiodarone because at this point we would consider the patient to be in shock refractory v-fib or v-tach [Music]

Channel: Lecturio Medical

Views: 67,314

Keywords: Epinephrine and Amiodarone, epinephrine injection, amiodarone mechanism of action, Amiodarone, Epinephrine, emergency medicine

Id: X-86kdR2UwU

Length: 7min 26sec (446 seconds)

Published: Mon Mar 12 2018