Cardiogenic Shock Nursing Management, Pathophysiology, Interventions NCLEX Review

hey everyone it's sarah register nurse rn.com and in this video we're going to be continuing our series on shock today we're going to be talking about cardiogenic shock now after you watch this youtube video you can access the free quiz that will test you on this condition so let's get started first let's start out talking about what is cardiogenic shock it occurs when the heart cannot pump enough blood to meet the perfusion needs of the body so this condition is solely an issue with this heart itself hence why we call it cardiogenic shock now why does it occur well can occur for multiple reasons number one it can occur due to a feeling issue there's an issue with these chambers of the heart being able to fill properly and this is known as diastolic dysfunction or there can be an issue with contraction of the heart so the heart is having a problem actually getting that blood and moving it forward out of the heart and that is known as a systolic dysfunction or you can have some type of dysrhythmia presenting or some type of structural defect a little bit later we will go into some conditions that can cause diastolic or systolic dysfunction but just keep that in mind now one thing with cardiogenic shock i want you to remember is that it doesn't present due to a loss of blood volume for the heart to pump the heart has plenty of blood volume to pump it just really can't pump it out of the heart and maintain cardiac output so that leads to a decrease in cardiac output now i really want you to remember cardiac output because this is a big term we're going to talk about throughout this lecture now what is it well it's the amount of blood that the heart pumps per minute and it's determined by a couple factors the heart rate and the stroke volume and stroke volume can be determined by your preload afterload and contractility and whenever we're talking about treatment we can give medications that can help manipulate that stroke volume hence increasing our cardiac output so whenever we have a decrease in cardiac output we're going to have decreased perfusion because this heart can't get its blood volume out to go to supply the organs the tissues so there are those cells that make up the organs and tissues aren't being perfused so if they're not receiving fresh oxygenated blood what's going to happen they're going to receive a decreased amount of oxygen and that can lead to cell hypoxic injury and we talked in depth about that in our previous video about the stages of shock now to help us truly understand cardiogenic shock we have to go back to the basics and we have to talk about the role of the heart our heart is the pump of the body and there is no other organ in our body that can do what the heart does and what's interesting is that every organ in the body depends on the heart so if the heart can't pump correctly everything else suffers because the heart supplies your organs and your tissues cells with fresh oxygen and they need oxygen to work and if the cardiac output falls which is the amount of blood that that heart pumps per minute that means that those cells aren't receiving adequate amounts of oxygen so as we learn in the stages of shock once that cardiac output starts to fall the patient will enter into those stages and in the end if it's not corrected the cells that make up the organs completely shut down and die and death occurs so what your heart does is that it receives blood to its right side everything starts in the right side and the whole goal is to take blood recycle it put fresh oxygen in it and pump it back out to the body so we have oxygen we have blood that's depleted of oxygen comes in through the superior inferior vena cava down through the right atrium then through the tricuspid valve the right ventricle which shoots it up through the pulmonic valve and then into the pulmonary artery which goes into the lungs and in the lungs gas exchange occurs and you have the crossover of carbon dioxide that has built up in the blood person will exhale that out then the oxygen that that person has taken in will cross over and go into the blood and then it will go back to the left side of the heart through the pulmonary vein and the goal of the left side is to take that oxygenated blood and pump it throughout the body so it will go through pulmonary vein through the left atrium down through the bicuspid slash mitral valve then through the left ventricle and the left ventricle is the main pumping chamber of the heart it's extremely strong and it's a very important chamber because if it fails to work and contract we have major problems and you're gonna where we talk about the causes in an acute myocardial infarction if you get damage to this left ventricle it's muscle we can have cardiogenic shock so left ventricle pumps it up through the aortic valve then through the aorta and the aorta will supply the body it'll branch off into this complex network of arteries and will go to every single organ tissue and supply the body with fresh oxygenated blood now let's talk about this thing called cardiac output understanding cardiac output is really the backbone of understanding cardiogenic shock so let's go over it okay as i have pointed out cardiac output is what it's the amount of blood pumped by this heart per minute so how much blood should your heart be pumping per minute it should be pumping anywhere between four to eight liters per minute now how can we determine cardiac output well you can take the heart rate and multiply it by stroke volume now let's talk about stroke volume for a moment if we can increase stroke volume in the management of cardiogenic shock we can increase cardiac output we increase cardiac output which is the amount of blood this heart is pumping per minute we can increase profusion to those cells that make up the tissues and organs they receive more oxygen they're happy and they don't start to die so stroke volume is the amount of blood pumped by the left ventricle with each beat which should be anywhere between 50 to 100 ml now stroke volume is determined by three factors and these three factors can be manipulated with medications to increase stroke volume so let's talk about those three factors they include preload afterload and contractility so preload is the amount those ventricles stretch at the end of diastole diastole is where the heart is relaxing and it's filling with blood so at the end when it's done filling at the end of that part of asleep it's the amount that those ventricles have stretched once it's filled afterload is the pressure the ventricle must pump against squeeze against to get blood out of the heart and then contractility is how well those muscle cells that make up that heart that help it contract how well they're contracting so it's the strength of the heart with each contraction now let's talk about some examples okay if we give a patient a drug that increases contractility like a positive inotropic drug like butamine dopamine if we increase contractility we're talking about we're increasing how well those muscle cells are contracting what's it going to do to stroke volume it's going to increase stroke volume okay afterload let's say we decrease that resistance that that heart has to pump against it's going to make it easier for the heart to pump so if we decrease afterload we're going to increase our stroke volume we can do that with like vasodilators now with preload let's say we give them a vasopressor it's pressing down our vascular system it's causing vasoconstriction when you vasoconstrict you're compressing everything you're going to increase venous return to the body so you're increasing the amount of blood that's coming to this heart which is going to increase how much is feeling in that ventricle how much it's going to have to stretch you're increasing its preload you bet you're going to increase its stroke volume as well so we can increase preload increase contractility decrease our afterload we're going to increase our stroke volume which is going to increase our cardiac output now another term you may see whenever talking about cardiogenic shock is something called cardiac index and all this is is it's a more specific measurement of cardiac output based on the patient's body size so it's calculated by taking the cardiac output and dividing it by the patient's body surface area and for patients who are in cardiogenic shock their cardiac index will be less than 2.2 liters per minute per meter squared and you want a normal cardiac index to be anywhere between 2.5 to 4 liters per minute per meter squared now let's talk about the causes of cardiogenic shock okay what are some conditions that can occur in the body that will make this heart's cardiac output fall so low that it can no longer meet the perfusion needs of our cells tissues and organs so they receive decreased oxygen well one of the main causes of this condition is if a patient experiences an acute myocardial infarction which is also called a heart attack and what happens during a heart attack is that the coronary arteries that set on your heart muscle have become blocked they can become blocked with a fatty plaque a clot or something but whatever the cause it's decreased blood flow to that heart muscle and wherever it's decreasing blood flow to that heart muscle those cells that make up the heart are going to not work and after so long those cells can just die and it's irreversible so that can lead to your heart not pumping efficiently hence stroke volume is majorly going to be affected which is going to make cardiac output fall and this is one of those systolic dysfunctions so there's going to be an issue with this heart being able to move blood forward and out of the heart and one type of acute mi that can cause this is if the coronary artery that feeds the left ventricle becomes blocked because remember what did i say about the left ventricle it's the main pumping chamber of the heart so the coronary artery that sets on that left ventricle is blocked wow that left ventricle is really going to become affected it's not going to pump it's going to affect its preload after low contractility you're going to have a mess on your hands and then stroke volume is going to fall and so is cardiac output so patients who have those type of heart attacks are really at risk for cardiogenic shock other causes of this condition are like pericardial tamponade and this is a diastolic dysfunction where there's going to be issues with the chambers of the heart being able to feel properly because you have too much fluid surrounding the heart so they really can't feel cardiac output is going to fall in addition dysrhythmias as i pointed out earlier myocarditis endocarditis can cause this also structural issues like issues with the valves or the septums in the heart now let's talk about the signs and symptoms of cardiogenic shock so whenever you're trying to recall these signs and symptoms for exams think about what is going on with this patient we know that there's decreased cardiac output so we have decreased cardiac output there's a limited amount of blood that's going to all those organs and tissues that depend on that heart to pump them fresh oxygenated blood so a lot of your signs and symptoms are going to stem from that in addition remember at the beginning of the lecture i said that this isn't a blood volume issue the heart has plenty of blood volume to pump which because it's weak and it's not being able to maintain cardiac output that blood volume is going to start to back up in the heart go to the lungs and go to the right side so that's really where you're going to see your other signs and symptoms so let's look at it by systems our heart our hearts weak it's not pumping correctly either we have a feeling issue like diastolic dysfunction or we have a systolic issue where the blood can't be pumped forward it's having issues with contractions or some type of thing but whatever the cause eventually what's going to happen is you're going to have back flow of blood because remember our blood volume is fine it's going to go to the lungs so it goes from left side back into the lungs it's going to go backwards instead of going from right to left shoulder it's really going to go left to right and you're going to have pulmonary edema lungs do not do well with fluid in them so what's going to happen in gas exchange it's going to decrease so you're going to get low o2 levels in the blood patients going to have difficulty breathing they're going to have an increased respiratory rate they're going to have an increased heart rate and chest x-ray if they get one of those it'll show pulmonary edema in there with infiltrates on the chest x-ray and if they have hemodynamic monitoring we're going to talk more about this in our nursing interventions but i wanted to include this in the signs and symptoms they can have an elevated pulmonary capillary wedge pressure also called a pulmonary artery wedge pressure greater than 18 millimeters of mercury and what this is it's measured through a pulmonary artery catheter goes in through the right side up through this pulmonary artery and the catheter on the end of it is like a balloon that can be inflated and deflated and it's temporarily inflated and that pulmonary arterial branch and it can measure the pressure and if you have a lot of blood that's back flowing into the lungs you're increasing the feeling pressure really that left atrium and it can measure that pressure and it'll be greater than 18 millimeters of mercury so keep that number in mind in addition you have the backflow from the lungs it'll eventually go to the right side because here's a pulmonary artery or right side of the heart and then venous circulation and all become congested increasing pressures on that right side so you can have jvd which is jugular venous distension where those neck veins will be distended and you can have a high central venous pressure where again you can measure the pressure in that right atrium and it'll be elevated from where you have that back flow of blood and it's increasing the pressure now with cardiac output wise you can have weak peripheral pulses you feel those the heart just can't pump it so whenever you feel those pulses they'll be weak systolic blood pressure will be less than 90 90 millimeters of mercury patient can say they're experiencing chest pain and this is where those coronary arteries aren't receiving blood as much blood flow perfusion as they should so it can't perfuse that heart muscle those cells are becoming stressed causing the patient pain and again cardiac index which was a specific cardiac output based on the patient's body size will be less than 2.2 liters per minute per meter squared now another system that's going to be affected is the brain and whenever cardiac output decreases so does the perfusion to the brain so you're going to have a drop in cerebral perfusion pressure so the cells aren't going to be perfused you're going to start seeing mental status changes in the patient they can start becoming confused agitated in addition this confusion and agitation can stem from the buildup of toxins because the liver isn't really going to be working efficiently by filtering out toxic substances along with the renal system and you'll be having acidotic conditions from the buildup of lactic acid so the kidneys can be affected as well so you can have decreased perfusion to the kidneys of course when cardiac output falls and the kidneys try to in a sense save themselves by activating the renin angiotensin system and what this does in a nutshell is the end result is the release of angiotensin ii and that is a major vasoconstrictor and whenever the body senses angiotensin ii aldosterone is released along with adh anti-diuretic hormone and what aldosterone is going to do is it's going to cause the body to keep sodium and water and adh is going to cause the body to keep water because in the end what it wants to do is increase blood volume because if it can increase blood volume it can increase venous return to the heart because it can get more perfusion if it does that so whenever that's happening what you're going to see is a lower urinary output augluria where you're going to have a urinary output of less than 30 cc's per hour so as an rsp watching that urinary output and if it's falling you know your kidneys are not being perfused very well which in addition whenever your kidneys are really struggling not being perfused you get an increase of bun and creatinine so be looking at that because that tells us our renal function and you can start seeing signs and symptoms in the skin where tissue perfusion is just falling the skin where where it should be nice and warm won't be like that it'll be cold cool clammy pale and when you check capillary refill it will be delayed it can be greater than two seconds now let's talk about nursing interventions for cardiogenic shock what are we going to be doing as the nurse okay first we need to know the treatment goals what's the medical treatment goals for this patient well number one reprofusion if this cardiogenic shock is happening due to let's say a coronary artery being blocked that feeds this heart muscle which is causing this heart muscle to become weak decreases its cardiac output they can hopefully re-establish profusion by doing heart catheterization putting in a stent so blood flow can start going back to that heart muscle another thing is increasing cardiac output and we can do that by giving certain medications and that can increase the stroke volume by altering that preload after load contractility and ventilation a lot of these patients who have severe cardiogenic shock are going to go into pulmonary edema where all that fluid is backing up into the lungs and and they will need mechanical ventilation with this and some diuretics to help remove the extra blood volume from the lungs so the patient can breathe easier so as a nurse a lot of times these patients are going to be in the icu because they're very sick so you'll be maintaining the hemo dynamic monitoring the mechanical ventilation due to the respiratory failure this hemodynamic monitoring can tell us a lot about our patient how they're responding to the iv drips that they're on and how their cardiac output is with a central line placement to help measure those numbers for cardiac output and they can do that through a pulmonary artery catheter like a swan gans in addition you want to monitor for signs and symptoms of adequate tissue perfusion and you can look at certain body systems and tell hey are they being perfused enough based on our cardiac output so look at the blood pressure we want this to solid greater than 90. skin color how does it look is it pale cool clammy probably not being perfused very well how's the capillary refill is it delayed urinary output is it greater than 30 cc's an hour if not kidney functions probably not good look at the bun and creatinine that can show if the patient's entering renal failure mental status the mental status will start to deteriorate as perfusion to those brain cells is decreased so is your patient becoming more confused agitated restless lung sounds that really ties to respiratory failure are your lungs clear if you hear crackles you probably have some pulmonary edema in there and how is the rhythm furthermore you'll want to look at lab results and other diagnostic testing that will be ordered to help look at the heart's function and what's possibly causing this cardiogenic shock cardiac markers will be ordered and they will be elevated for example troponin level will be elevated and a bmp could be elevated now what is a troponin well troponin is a substance released when there is injury to the heart muscle cells and we know in cardiogenic shock that these cells are getting stressed out so this can increase troponin levels and especially can increase troponin levels if there's been significant damage to the heart muscle cells through like a myocardial infarction now what's a bnp well this is a substance released by the ventricles heart cells due to stretching from high blood volume in the ventricle and we know as that heart muscle is getting weaker and weaker blood volume starts to back up and that will increase the amount that those ventricles are having to pump other tests that can be ordered of course is like a chest x-ray where this would show fluid in the lungs pulmonary edema in addition a serum lactate can be ordered and this will be greater than four millimoles per liter and why are we having elevated lactic acid levels well remember when we talked about the stages of shock we talked about how the cells will switch from aerobic to anaerobic metabolism so they are using metabolism at first with oxygen the aerobic but oxygen isn't in supply so they're going to have to switch to anaerobic metabolism without oxygen and this leads to the accumulation of lactic acid as a result so then we'll start getting acidotic conditions where there will be a drop in the blood's ph less than 7.35 now let's talk about some hemodynamic monitoring numbers that you need to know when we're talking about cardiogenic shock okay the first one i've already hit on a little bit it's called the pulmonary capillary wedge pressure or the pulmonary artery wedge pressure and in cardiogenic shock this number is going to be high and normal is 4 to 12 millimeters of mercury but in cardiogenic shock it's going to be elevated greater than 18. and again that was with like a swan gans catheter pulmonary artery catheter it's inserted in that right side and it's going to go up into that pulmonary artery and it's going to be hence wedge the tip of that catheter and a balloon is temporarily going to be inflated in that pulmonary arterial branch it's going to measure the pressure and it's going to really tell us the pressure on that left side of that left atrium so if the pressure is high from where we're having the back flow of blood it's going to be elevated another thing we can look at is the central venous pressure the cvp it will be elevated as well and this is because we have back flow of blood causing venous congestion in this right side and it's measured over here in this area now let's talk about medications okay with medications for cardiogenic shock you can have various medications depending on what is causing it um how the patient is even responding to treatment you may use this medication on this patient while you wouldn't use it on this patient because the response is different these medications are going to be titrated their iv and things like that so keep that in mind so some medications that can be used are diuretics why would we need diuretics well remember with cardiogenic shock we don't have a blood volume issue this is one of the two shock types the other is neurogenic where we don't have decreased blood volume our blood volume is actually causing us some problems because our heart is not able to really pump it forward so we're getting congestion so diuretics can be used like furosemide which is the brand name lasix give that iv that'll help draw some fluid out it's loop diuretics they'll urinate that fluid and help remove all that pulmonary congestion in the lungs however when you give these diuretics especially lasix it can cause hypokalemia it wastes potassium so before you give any type of diuretics you always want to look at electrolyte levels and if they're getting this medication you want to make sure your potassium is within 3.5 to 5 milli equivalents per liter anything lower than that 3.5 you just want to give the physician a call so they can provide some supplementation before you throw on this diuretic so what the what's this going to do is it's going to remove that extra blood volume it's going to decrease that workload of the heart and you'd want to watch out for hypotension because if we're taking off blood volume through having them urinated out we can make them have a lower blood pressure and chances are we're already dealing with someone who is hypotensive so you'd want to monitor that closely and if they get too hypotensive they can throw on another medication to help increase that pressure so be watching out for that also looking at their fluid status what's the urinary output how's their kidney function because we don't want to cause them to go into renal failure by throwing these diuretics on another category of drugs used are called vasopressors and what these do is they cause constriction of the vessel so major vasoconstriction and as we talked about before you're going to have increased preload with that because it's really just going to clamp down on those vessels increase venous return and preload was the amount those ventricles stretched at the end of diastole and if you increase that in the end that's going to increase stroke volume so you'll have increased cardiac output increased blood pressure a drug that's a vasopressor uses called norepinephrine and we'll get the results of increased cardiac output with this to tissue perfusion our cells will be happy because they will get more oxygen now there are some vasopressors that have positive inotropic effects and inotropic whenever they have positive anatropic effects that means that they're increasing the contractility of the heart and that was another factor in stroke volume so we're going to increase the strength of the heart's contractions which is great because we're going to have better stroke volume higher cardiac output two drugs that can do that that are used in cardiogenic shock we have dobutamine so dobutamine increases contractility increases stroke volume but a side effect because the way that dobutamine acts on certain receptors it can actually cause vasodilation which can in our patient who already is hypotensive it can cause it to get worse and they'll probably have to be switched or started on norepinephrine or dopamine instead so you want to watch out with dobutamine worsening hypotension that's a big thing with that now dopamine is a positive anatropic effect as well it increases contractility which is going to increase our stroke volume however a side effect of dopamine is that it can cause a tachycardic can really increase that heart rate so you have to watch the heart rate with this medication in addition we have vasodilators that's another category and what these do is they decrease afterload which was one of those factors in stroke volume so whenever we decrease the afterload it's going to make easier for the ventricle to pump against that resistance so we have decreased resistance that that heart has to pump against and it also dilates our coronary arteries which is going to increase perfusion to the heart muscle so our heart's going to get more blood flow because those dilated coronary arteries but a side effect of this is hypotension so we really have to watch out for that blood pressure make sure it's stabilized because it can further make it worse and some vasodilators are like nitroglycerin or sodium nitroprusside and some other things that can be ordered in a patient with cardiogenic shock or like iv fluids like normal saline however they're typically not ordered if you have a patient in fluid overload with like pulmonary edema because if we throw more fluid in here in the heart they already have fluid in the lungs from where that heart's weak and not pumping correctly we're going to cause them some more issues so if they are ordered they're used with extreme caution and fluid challenges are more common in the other types of shock that we'll be going over rather than cardiogenic shock because remember blood volume is not really an issue with us it's our heart now let's quickly talk about intra aortic balloon pumps what are these they are a device used to help improve coronary artery blood flow and to increase cardiac output so this catheter is inserted through a vessel it goes up through this aorta sets in a section of the aorta and the catheter has a balloon at the end of it and what this balloon will do is it will inflate and deflate at certain times and this will actually increase blood flow to the heart muscle via those coronary arteries and increase cardiac output so during um sicily that balloon will actually deflate so here you have this balloon it's deflating and whenever the heart is in sicily contraction whenever you have that balloon that deflates it creates a suction like pressure so what that's going to do is it's going to suck more blood out of this weak side of the heart that's having trouble pushing blood forward it's going to suck it out help it go out through the body increasing cardiac output and pushing more blood into those coronary arteries because coming off the aorta is are the coronary arteries in addition whenever you have diastole where the heart's like resting and feeling the balloon is going to inflate so when you have to isolate this balloon inflates the aortic valve is closed during that time it's going to push blood flow into those coronary arteries and even further increase profusion to the heart muscle okay so that wraps up this review over cardiogenic shock thank you so much for watching don't forget to take the free quiz and to subscribe to our channel for more videos

Channel: RegisteredNurseRN

Views: 869,088

Keywords: cardiogenic shock, cardiogenic shock management, cardiogenic shock pathophysiology, cardiogenic shock made easy, cardiogenic shock nursing interventions, cardiogenic shock nclex, types of shock, shock, shock pathology, management of shock, shock symptoms

Id: VJdygiX_pyY

Length: 32min 22sec (1942 seconds)

Published: Sat Dec 22 2018