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Current time:0:00Total duration:7:04

Video transcript

let's talk about electroshock therapy so sometimes healthcare providers use electrical shocks to bring patients out of ear regular heart rhythms or irregularly fast heart rates and the goal is to reestablish a normal heart rate and rhythm so you've probably seen scenes in movies or on TV where there's a patient in the hospital and all of a sudden the patient's eyes roll back and there's pandemonium in the room someone yells the patient's heart stopped the doctor comes running into the room puts two paddles in the patient's chest and then yells clear in this scene our scenario the healthcare provider is using something called a defibrillator which is a machine that shocks the heart so in the movies usually the patient's knocking on death's door and has no heartbeat but in reality electroshock therapy is actually used to treat a number of different admirable heart rates and rhythms for example it's used to treat atrial fibrillation and that's where the upper chambers of the heart are spasming so atrial fibrillation sometimes is known as a fib for short another rhythm it treats is ventricular tachycardia or v-tach where the ventricles are beating way too fast in addition to afib in v-tach there are a number of other different rates and rhythms that are treated with shock therapy and we'll talk about those in a second so again in the movies the patient's usually unconscious and has no heartbeat but in reality sometimes the patient's actually awake until just before the shock and these patients will receive sedating medication just before the shock to help them fall asleep because you can imagine that getting a shock to the chest hurts and again in the movies we typically see that people are getting shocked in emergency situations but in reality electroshock therapy isn't always an emergency there are some situations where people actually booked this shock therapy as an outpatient procedure so a defibrillator can shock a patient in one of two settings the first is synchronized electrical cardioversion and synchronized cardioversion the defibrillator delivers a shock in sync with the R wave on the QRS complex so again the shock is delivered and sync with the R wave which is why it's called synchronized cardioversion synchronized Carney versions used for certain arrhythmias such as atrial fibrillation or afib like we talked about up here it's also used a tree atrial flutter which is another type of super ventricular tachycardia just like afib it's used to treat atrioventricular nodal reentrant tachycardia which is a fast heart rate caused by an abnormal loop or a circuit of electricity going around the AV node and synchronized cardioversion is used to treat someone with v-tach who has a pulse now why do we care about the pulse in someone with v-tach whether or not they have a pulse actually determines how we treat this patient so the person has a pulse and a stable meaning that they have normal blood pressure and no chest pain and they have a normal mental status they're not coming in and out of consciousness these people receive medication for treatment and someone with v-tach with a pulse who is unstable meaning that their blood pressure is low or they're experiencing chest pain because our hearts beating so fast they can't circulate blood well enough to the heart to get oxygenated blood or if they have an altered Mental Status meaning that they're falling in and out of consciousness or they're confused these people who are unstable with a pulse in v-tach will undergo synchronized electrical cardioversion someone in v-tach without a pulse well they're gonna go straight to defibrillation which is the second setting on the defibrillator again so BTech without a pulse defibrillation in different relation the electrical shock is given at any point in the cardiac cycle so again it's given anytime in the cycle it's not in sync with the are waver anyway for that matter so sometimes defibrillation is called asynchronous cardioversion a meaning no synchrony because it's not synchronizing to any part of the cycle defibrillation is used on patients who are seconds away from death and who have no pulse it's used in ventricular fibrillation where there is no coordinated lecture activity in the heart instead the ventricles are just spasming and there's no pulse so what's another arrhythmia where there's no pulse well remember sometimes v-tach does have a pulse and in the case of v-tach without a pulse we're gonna treat that with defibrillation another difference in the two settings is that in defibrillation a higher energy level is used so defibrillation is going to use a higher energy level when delivering the shock so how does electroshock therapy work shock therapy works by shocking all of the heart cells at once and depolarizing all of the heart cells at the same time what happens after depolarization repolarization and the cells go into their refractory periods the refractory period is sort of like the recovery time or the window of time where the cells can't create another action potential so depolarizing all of the heart cells simultaneously briefly prevents the tissues from being transmitted electro signals because the cells are busy recharging they're in this refractory period this last time for the heart to reset and allows the heart spacers to sort of reclaim their dominant pacing role in short it's kind of like when your computer starts active what do you usually do when your computer starts acting though well usually reboot and so just like you reset your computer you're resetting the heart so next time you reboot your computer it's almost like you're putting paddles on it and yelling clear [Music]