Transcript for:
Understanding Cardiovascular Emergencies and Care

and welcome to chapter 17 cardiovascular emergencies of the emergency care and transportation of the sick and injured 12th edition after you complete this chapter and the related coursework you will understand the significance and characteristics of the anatomy and physiology of the cardiovascular system cardiovascular emergencies the pathophysiology of respiration and perfusion signs and symptoms of the most common cardiac conditions the indications contraindications and the use of an aed and the general care of a patient experiencing a cardiac emergency we'll be able to apply this fundamental knowledge to patient assessment and management during in-classroom scenarios okay so cardiovascular disease has been the leading killer of americans since the 1900s and it accounts for about one of every three deaths ems can help reduce deaths by providing the following services so we can encourage people to follow a healthy lifestyle access medical care early provide more cpr training of lay people increased use of evolving technology in dispatching cardiac arrest response public access to defibrillation devices and recognition of the need for advanced life support care and also the use of cardiac specialty centers when they are available so let's talk about some anatomy and physiology of the cardiovascular system so the jobs the heart job is to pump blood to supply oxygen and rich red blood cells to the tissues of the body remember the heart is divided down the middle into the left and right sides each with an upper chamber which is the atrium to receive incoming blood and the lower change of chambers which is the ventricles to pump outgoing blood this figures figure shows an illustration of the four chambers of the heart so blood leaves each of the four chambers of the heart through one-way valves which keep the blood flowing in the circulatory system in the proper direction the aorta that's the body's main artery it receives blood ejected from the left ventricle and delivers it to all the other arteries that supply the body's tissues and this figure on the slide illustrates the hearts the blood supply so the right side of the heart receives oxygen poor blood from the venous circulation and the left side receives oxygen rich blood through the pulmonary arteries okay so the heart's electrical system controls the heart rate and coordinates the work of the atria and ventricles the heart generates its own electrical impulse starting at the sinus node the impulse passes through the atria to the ventricles automaticity allows spontaneous circulation without a stimulus from a nerve source as long as the impulses come from the sa node and other myocardial cells will contract when the impulse reaches them if no impulse arrives however the other myocardial cells are capable of creating their own impulses and stimulating circulation okay so this figure on the side illustrates the conduction system of the heart so at the top you see in the green the sa node traveling down through those pathways to the av node into the bundle of his and then finally into the purkinje fibers the left bundle branch okay and so the autonomic nervous system controls involuntary activities of the body the autonomic nervous system has two parts which normally balance one another you have the sympathetic nervous system and then you have the parasympathetic nervous system the myocardium must have a continuous supply of oxygen and nutrients to pump blood so cardiac output is increased by increasing the heart rate or stroke volume in a normal heart the increased oxygen demand of the myocardium itself is accomplished by increasing the blood of the blood delivered to the myocardium by dilating the coronary arteries the coronary arteries are blood vessels that supply blood to the heart muscle so they start at the first part of the aorta just above the aortic valve the right coronary artery supplies blood to the right atrium and right ventricle and in most people the inferior wall of the left ventricle the left coronary artery supplies blood to the left atrium the left ventricle and divides into two major branches just a short distance from the aorta and so you could see on this figure on the slide it illustrates those arteries the different coronary arteries okay the arteries supply oxygenated blood to different parts of the body and so we have the right and left carotid arteries and they supply blood to the head and the brain the right and left subclavian arteries supply the upper extremities the brachial arteries supply the arms the radial and ulnar arteries supply the lower arms and hands the right and left iliac artery supply the groin pelvis and legs and the right and left femoral arteries supply the legs the anterior and posterior tibial arteries supply the lower legs and feet the arterioles and capillaries are smaller vessels that receive blood from the arteries capillaries are one cell thick and it exchanges nutrients and oxygens for waste at a cellular level connects our arterials to venules okay so the venules and veins receive blood from the capillaries the venules are the smallest branches of the veins the vena cava returns oxygen poor blood to the heart you have the superior vena cava that carries blood from the head and the arms back to the right atrium then the inferior vena cava it carries blood from the abdomen kidneys legs back to the right atrium so blood consists of types of cells and fluid you have the four types and that's the red blood cells and those carry oxygen and remove the carbon dioxide then you have white blood cells and those are the fighters they fight infections the platelets help blood to clot and plasma is the fluid that the cells float in so blood pressure is the force of the circulating blood against the artery walls so when you talk about the systolic blood pressure it's the maximum pressure generated in the arms and legs during the contraction of the left ventricle during the time period known as systole diastole is the blood pressure against the artery walls when the left ventricle is relaxing and then there's the pulse and that's felt when the blood passes through the artery during systole so peripheral pulses are felt in the extremities and central pulses are felt near the trunk of the body in this figure it shows the different areas to take the pulse and so you'll see the femoral the brachial the carotid radial posterior tibial and the dorsalis pedis okay so the cardiac output is defined as the volume of blood that passes through the heart in one minute and so you could calculate that by multiplying the heart rate by the volume of blood ejected with each contraction or also known as a stroke volume so but in the field stroke volume can be roughly determined by the heart rate and the strength of the patient's pulse perfusion describes a constant flow of oxygenated blood to the tissues we have to have good perfusion um in order to have good perfusion though we have to have a well-functioning heart we have to have adequate volume of fluid or blood and the blood vessels must be appropriately constricted to match the volume of blood valuable okay so if perfusion fails though we're going to have cellular death and eventually the patient's going to die all right so we've talked a little about the anatomy let's talk a little bit about the physi the pathophysiology okay so heart related chest pain usually stems from ischemia which is decreased blood flow to the heart or inefficient supply of oxygen nutrients ischemic heart disease involves a decrease in blood flow to one or more portions of the heart muscle and if the blood flow is not restored the tissue is going to die so here's atherosclerosis and it's a disorder in which calcium and cholesterol build up and form plaque inside the walls of the blood vessels it can cause complete occlusion or block of a coronary artery and other arteries of the body so fatty material accumulates as a person ages resulting in the narrowing of the luminum aluminum and so the inner wall of the artery becomes rough and brittle if a brittle plaque develops a crack or for unknown reasons the ragged edge of the crack activates blood clotting system so the results would be a blood clot that would partially or completely block the luminum of the artery and that is atherosclerosis a thromboembolism is a blood clot that floats through a blood vessel if it reaches an area too narrow to pass it stops and blocks that flow so tissues downstream of the blood clot will suffer from hypoxia if too much time has passed before the blood flow is resumed the tissues will die this sequence of events is known as a myocardial infarct or a classic heart attack the death of heart muscle can severely diminish the heart's ability to pump in the united states coronary artery disease is the number one cause of death for men and women the peak incidence of heart disease is between about 45 and 64 years old so but it can strike in individuals reigning ranging from their teens to their 90s risk factors place a person at higher risk for an ami or acute myocardial infarction some of these risk factors we can control and controlling risk factors are cigarette smoking or high blood pressure elevated cholesterol diabetes lack of exercise and obesity but some risk factors we cannot control and the major uncontrollable risk factors are old age family history race ethnicity and the male being male sex acute coronary syndrome describes a group of symptoms caused by a myocardial ischemia so this includes temporary myocardial ischemia which results in angina pectoris or a more specific condition or more more serious condition an acute myocardial infarct angina pectoris occurs when the heart's need for oxygen exceeds the available supply usually during physical or emotional stress so it can result from a spasm of the artery but is most often a symptom of atherosclerotic coronary artery disease it may be triggered by large meal or sudden fear or when increased oxygen man goes away the pain typically goes away so angina pain is commonly described as crushing squeezing or somebody is standing on my chest it's usually felt in the mid portion of the chest or under the sternum it can radiate into the jaws or arms frequently the left arm mid back or epigastrum it usually lasts from three to eight minutes but rarely longer than 15 minutes it may be associated with shortness of breath nausea or sweating usually disappears promptly with rest supplemental oxygen or nitro although angina does not usually lead to death or permanent heart damage it is a warning sign that should be taken seriously unstable angina is characterized by pain or discomfort that occurs in the absence of a specific increase in the myocardial oxygen demand stable angina is characterized by pain in the left in the chest of coronary origin that occurs in response to exercise or some physical activity that increases the demand on the heart that is beyond the heart's capacity to increase its own blood flow patients experiencing chest pain or discomfort should always be treated as if they're having an acute myocardial infarct the pain of an ami or acute myofa cardial infarct signals the actual death of cells in the area of the heart where the blood flow is obstructed once the cells are dead the cells cannot be revived they will turn to scar tissue and become a burden to the beating heart about 30 minutes after blood flow is cut off the heart muscle begins to die after about two hours as many as half of the cells in that area may be dead after about four to six hours more than 90 percent of the cells will be dead opening the coronary artery with either a clot busting which is a thrombolytic drug or angioplasty it's a way of clearing the artery can prevent permanent damage if it's done within the first few hours after the onset of symptoms so immediate transport is essential it is more likely to occur in the left ventricle and so signs and symptoms of an ami include the following sudden onset of weakness nausea and sweating chest pain discomfort or pressure that is often crushing or squeezing that does not change with each breath pain discomfort or pressure in the lower jaw arms back abdomen or neck an irregular heartbeat or sinkable episode shortness of breath nausea vomiting pink frothy sputum or sudden death the pain of an acute myocardial infarct differs from pain of angina in three ways it may or may not be caused by exertion and can occur at any time sometimes the person is sitting quietly or even sleeping it does not resolve in a few minutes rather it can last between 30 minutes to several hours and it may or may not be relieved by rest or nitro not all patients who are having an ami experience pain or recognize when it occurs so when called to the scene where the chief complaint is chest pain complete a thorough assessment no matter what the patient says so some physical findings of an ami and cardiac compromise include appearance a general appearance of fear or nausea or some type of poor circulation the pulse could be faster irregular or bradycardic the blood pressure could be decreased normal or elevated respirations could be normal or rapid in labor mental status or fillings of impending doom sudden death cardiogenic shock or congestive heart failure okay so let's talk about dysrhythmias and so dysrhythmias describes an abnormality of the heart rhythm so first uh dysrhythmia we're going to talk about is a premature ventricular contractions and they are an extra beat in a damaged ventricle they're usually harmless and common among healthy as well as sick people then then you have tachycardia and so that's a fast rapid heartbeat and it could be 100 beats or more a minute then bradycardia that describes an unusually slow beating of the heart that's 60 beats per minute or less you could also have a rhythm called ventricular tachycardia and it describes a very rapid heart rate rhythm this is a 150 to 200 beats and it can deteriorate very fast into a rhythm called ventricular fibrillation so ventricular fibrillation describes the disorganized ineffective quivering of the ventricles and no blood is pumped through the body and the patient usually becomes unconscious within seconds defibrillation may convert this arrhythmia so think of ventricular fibrillation fibrillation we want to defibrillate it so defibrillation defibrillation is what we use to convert it or an aet defibrillation is the process of shocking the heart with a specialized electrical current to restore a normal cardiac rhythm it can save lives if the shock is delivered within the first few minutes of sudden death cpr must be initiated until the defibrillator is available then chances of survival diminish appropriately seven to ten percent each minute until a defibrillation is accomplished a systole is the next heart rhythm we're going to talk about it's a dysrhythmia and a systole is basically the absence of all electrical activity it usually reflects a long period of ischemia and nearly all patients with a sleep will die all right so let's talk about cardiogenic shock and so cardiogenic shock is going to occur when the body tissue doesn't get enough oxygen and this is because of the heart all right and so this will cause body organs to malfunction cardiogenic shock is often caused by a heart attack the heart lacks the power to force enough blood through the court the circulatory system and it is more common in an acute myocardial infarction affecting the inferior and posterior regions of that left ventricle it's important to recognize shock in the early stages so that leads us into congestive heart failure all right so congestive heart failure often occurs within the first few days after a myocardial infarct and so what it is is congestive heart failure develops when increased heart rate and an enlargement of that left ventricle no longer make up for the decreased heart okay so it's called congestive because the lungs become congested with fluid and that's pulmonary edema once the heart fails to pump effectively so it occurs suddenly or it could occur slowly over months in an acute onset of congestive heart failure severe pulmonary edema is accompanied usually by pink frothy sputum and severe dipsnia so with right-sided heart failure blood backs up in the vena cava this causes fluid to collect in other parts of the body so you could have what's called dependent edema so swollen ankles such as in the feet and legs right-sided heart failure can result in an inadequate supply of blood to the left ventricle so this results in a drop in the systemic blood pressure patients may result may present with signs of both left and right sided heart failure because the left side failure often leads to the right side failure hypertensive emergencies involve any systolic blood pressure greater than 100 millimeters per mercury or a rapid increase in the systolic pressure sudden severe headaches is a common size also some other symptoms are strong bounding pulse and ringing in the ears nausea and vomiting dizziness warm skin some nosebleeds altered mental status or sudden development of pulmonary edema untreated a hypertensive emergency can lead to a stroke or a dissecting aortic aneurysm so transport patients to the hospital as quickly and safely as possible consider advanced life support assistance depending on transport distance and time so an aortic aneurysm describes a weakness of the wall of the aorta the aorta dilates at that weakened area in which a it's susceptible to rupture and if it ruptures blood loss will cause the patient to die almost immediately uncontrolled hypertension is a primary cause of dissecting aortic aneurysm a dissecting aneurysm occurs when the inner liner of the aorta becomes separated allowing blood flow to allowing blood to flow at high pressure between those layers signs and symptoms include very sudden chest pain located in the anterior part of the chest or the back between the shoulder blades it may be difficult to differentiate the pain of a dissecting aortic aneurysm from an acute myocardial infarct so transport the patients to the hospital as quickly and safely as possible so on this table you're going to see the difference between the acute myocardial infarct and the dissecting aneurysm and what i like to note point out is that with the onset of pain with a heart attack or ami you have a gradual usually slow onset of pain and it has a tightness or pressure with that aneurysm it's abrupt without additional symptoms and usually you'll see it or hear it as sharp or tearing okay severity with a heart attack increases with time whereas the dissecting it is maximum on onset okay so let's get into the patient assessment so in the patient assessment we're going to do that scene size up always and a cure ensures same safety and we're going to determine that it's a nature of illness we're going to use the dispatcher info clues and comments from family members and bystanders our primary assessment when we form that general impression if the patient's unresponsive and not breathing we're going to start cpr right away and call for an aed we're going to assess the patient's airway and breathing if dizziness or fainting has occurred due to cardiac compromise we're going to consider the possibility of a spinal injury okay so assess breathing to determine whether their the ailing heart is receiving adequate oxygen so if they have shortness of breath or with no signs of respiratory distress if oxygen saturation is less than 95 administer oxygen at 4 liters if they do not improve quickly apply oxygen with a non-rebreather if not breathing or breathing inadequately we're going to apply 100 oxygen with the bag valve mask pulmonary edema if that's present we're going to do positive pressure ventilations with the bag valve mask or we could use cpap okay we're going to assess the patient's circulation pulse rate and quality skin color nature and temp capillary refill we're going to consider treatment for cardiogenic shock early to re reduce the workload of the heart we're going to position the patient in the comfortable position usually sitting up and while supported we're going to make a transport decision based on whether you were able to stabilize life threats during the primary assessment so the remainder of the assessment can be performed in route if time allows most patients with chest pain should be transported immediately we're going to follow our local protocol for determining what receiving facility is most appropriate we're going to determine whether to use lights or sirens for each patient based on an estimated transport time and as a general rule patients with cardiac problems should be transported in the most gentle stress relieving manner okay so the next part of our patient assessment is the history taking and we're going to investigate the chief complaint and because patients experience an acute myocardial infarct will have different signs and symptoms seriously consider all complaints of chest pain or discomfort shortness of breath and dizziness if a patient is experiencing dyspnea is it due to exertion or related to the patient's position and is it continuous or does it change with each breath if the patient has a cough is it does it produce sputum and does the patient have nausea and vomiting fatigue headache or palpations ask about recent post trauma um obtain sample history and of course this is from the responsive patient and this is the the history of the patient so we're gonna ask have you ever had a heart attack have you been told that you have heart problems do you have any risk factors for coronary artery disease in addition we're going to ask what allergies is the patient at taking medications and include those opq rst when obtaining the symptoms as part of the sample history so this slide displays the mnemonic for assessing pain and it'll show you the opqrst mnemonic and that's the onset provocation palpation quality region radiation severity and timing next part of the patient assessment is the secondary assessment and of course because it's a chest pain situation we're going to focus on the cardiac and respiratory systems circulation and respirations we're going to measure and record the patient's vital signs so the pulse respirations systolic and diastolic pressures in both arms and if available we're going to use a pulse ox if continuous blood pressure monitoring is available we're going to use that as well and we're going to repeat at appropriate intervals and note the time that each set of vital signs is taken and recorded if patients with chest pain it is very valuable to have a 12 lead tracing from as early as possible after the onset of chest pain and then our reassessment so we're going to repeat the primary assessment by checking to see whether the patient's chief complaint and condition have improved or are deteriorating we're going to reassess vital signs at least every five minutes or anytime significant changes in the patient's condition occurs sudden cardiac arrest i is always a risk with patients experiencing cardiovascular emergency so if cardio cardiac arrest occurs have an aed immediately available and if not perform cpr immediately until the aed is available then reassess your interventions provide transport if not performed already communication and document so alert the emergency department about the patient's condition and estimated time of arrival and follow your instructions of the medical control and document your assessment and treatment of the patient emergency medical care for chest pain or discomfort okay so let's talk about this so we're going to ensure a proper position of comfort allow patients to sit up if most comfortable loosen tight clothing give oxygen if indicated so continually reassess oxygen saturation in in the patient's respiratory status you can use a nasal cannula for patients with mild dipsnia or a non-rebreather mask for patients with more serious respiratory difficulty if pulmonary edema is present cpap may be indicated assist unconscious patients with breathing as well with uh or with those an obvious respiratory distress and depending on your protocol prepare to administer low dose aspirin and assist with prescribed nitro so let's talk about aspirin aspirin prevents new clots from forming or new existing clots from getting bigger so recommended dose is between 120 or 162 to 324 we're going to lose use low dose aspirin which is 81 milligrams then nitro nitro is available in a small tablet spray or skin patch the mechanism of injury relaxes the muscles of the blood vessel walls dilates coronary arteries and increases blood flow and supply to the heart it decreases the workload of the heart side effects include decreased blood pressure severe headache contraindications are systolic blood pressure less than 100 milli meters of mercury head injury or the use of dis disrectile dysfunctional drugs within 24 to 48 hours maximum prescribed dose has already been taken which is three doses that's a contraindication and also cardiac monitoring okay so for an ecg to be reliable and useful the electrodes must be placed in consistent positions on each patient okay certain basic principles should be followed to achieve the best skin contact and minimize artifact in the signal guiding principles it may be okay it may occasionally be necessary to shave body hair from the electrode site rub the electrodes bristly with alcohol swab before application to remove oils and dead tissues from the surface of the skin attach the electrodes to the ekg cables before placement confirm that the appropriate electrode now attached to the cable is placed at the correct location on the patient's chest or limbs so this is going to show you cardiac monitoring limb placement sites okay so that there's the limb leads on the left side of the slide and then the 12 lead once all electrodes are in place switch on the monitor print a sample rhythm strip the strip shows any artifact verified that the electrodes are firmly applied to the skin and the monitor cable is plugged correctly we're going to follow the skill drill in 17-2 okay so heart surgeries and cardiac assistant devices so over the last 40 years hundreds of thousands of open heart surgeries have been performed to bypass damaged segments of coronary arteries in the heart in a coronary artery bypass graft a blood vessel from the chest or leg is sewn directly from the aorta to the coronary artery beyond the point of obstruction percutaneous transluminal coronary angioplasty dilates the affected artery rather than bypassing it and involves the following steps so a tiny balloon is attached to the end of each to attach the end of a long thin tube and introduced into the large artery the tube is threaded into the narrow coronary artery and inflated the balloon is then deflated and the tube and the balloon are removed sometimes a stent is placed inside the artery patients who have had bypass procedures may or may not have a long scar on their chest treat chest pain in a patient who has had any of these procedures in the same way you would treat chest pain in patients who have not had the heart surgeries some people have cardiac pacemakers to maintain a regular cardiac rhythm and rate they are inserted when the electrical system of the heart is so damaged that it cannot function properly these battery-powered devices deliver an electrical impulse through the wires that are in direct contact with the myocardium the generating unit typically resolves resembles a silver dollar and is usually placed under the heavy muscle or fold of the skin in the upper left upper portion of the chest so emts normally do not need to be concerned about problems with pacemakers when they do not function properly pacemakers can cause the patient to experience syncope dizziness or weakness due to an excessively slow heart rate the pulse will year ordinarily be less than 60 beats per minute and a patient with a malfunctioning pacemaker should be promptly transported to the emergency department when the aed is used the patches should be should not be placed directly over the pacemaker okay so automatic implantable cardiac defibrillators are sometimes used in patients who have survived cardiac arrest due to ventricular fibrillation these devices continuously monitor the heart rhythm and deliver shocks as needed treat these patients like you would any other acute myocardial infarction including performing cpr and using an aed if the patient goes into cardiac arrest the electricity from the aed that is implanted is so low that it will have no effect on rescuers so then there's an external defibrillator vest and this is a vest with a built-in monitoring electrodes and defibrillation pads which is worn by the patient under under his or her clothing the vest is attached to a monitor worn on the belt or hung from a shoulder strap the device uses high energy shocks similar to an aed so you should avoid contact with the patient if the device warns you that it's about to deliver a shock the vest should remain in place while cpr is being performed unless it interferes with the compressions if it is necessary to remove the device or the vest simply remove the battery from the monitor and then remove the device then you have lvads lvads are left ventricular assist devices and this is used to enhance the pumping of that left ventricle in patients with severe heart failure or in patients who need a temporary boost due to mi the most common ones have an internal pump unit and have an external battery pack the pumps are almost all continuous so most patients will not have a palpable pulse unless the device malfunctions you should not have to deal with it contact medical control if there is any doubt in what to do and you need to transport all lvad supplies and battery packs with the patient then there's cardiac arrest so cardiac arrest is the complete cessation of cardiac activity electrical mechanical or both if it is indicated in the field by the presence of absence of carotid pulse cardiac arrest was almost always terminal until the in the advent of cpr and external defibrillation in the 1960s with good cpr early defibrillation and access to advanced care it's possible for some patients to survive cardiac arrest without neurological damage okay so now we're going to talk about aeds and this is an automated external defibrillation and it involves the use of a small computer and that computer is an aed that analyzes electrical signals from the heart it identifies ventricular fibrillation and is extremely accurate it administers a shock to the heart when needed so uh come in different models and the models require some operator interaction so such as like applying pads or turning the machine on the operator must push a button to deliver an electrical shock and many use a computer device synthesizer to advise the emt which steps to take and most of the aeds are semi-automated or extremely accurate an advantages of aeds include quick delivery of electrical shock they're easy to operate you don't have to have advanced life support providers on scene remote adhesive defibrillator pads are safe to use and large pad area with manual paddles which means that transmission of electricity is more effective efficient other considerations when using the aeg includes so not all patients in cardiac arrest need an electrical shock so all patients in cardiac arrest should be analyzed with an aed though but some do not have shockable rhythms for example a systole which is that flat line indicates that there's no electrical activity so it will not need a shock and then a rhythm called pulseless electrical activity and this usually refers to a state of cardiac arrest that exists despite an organized electrical complex that will not need an electrical shock okay but early defibrillation is an essential intervention for patients experiencing cardiac arrest few patients who experience sudden cardiac arrest outside the hospital survive unless a rapid sequence of events take place and so these are called the chain of survival links and you need to have all of them linked or else there's not going to be survivability so we need to have recognition of early warning signs and we need to call ems immediately okay and then immediate cpr needs to be done with emphasis on high quality chest compressions rapid defibrillation needs to occur basic and advanced ems needs to take place and then advanced life support with post-arrest care and then finally recovery and here this figure illustrates the chain of survival cpr helps patients in cardiac arrest by prolonging the period during which defibrillation can be effective rapid defibrillation has successfully resuscitated many patients in cardiac arrest and defibrillation works best if takes place within two minutes of the onset of cardiac arrest non-traditional first responders are being trained to use aeds the fifth step in the chain of survival is advanced life support and post-arrest care this involves the continued ventilations at 10 to 12 breaths a minute maintain oxygen saturation between 99 or 94 to 99 ensure the blood pressure is above 90 millimeters of mercury use a targeted temperature management when the patient arrives at the hospital cardiopulmonary and neurologic support along with advanced assessment techniques and interventions when indicated then the final step in the chain is recovery so this is recovery can take a year or longer for many of the ten percent of victims of out of the hospital cardiac arrest who are fortunate enough to survive when integrating the aed and cpr into patient care keep the following in mind it is usually important to work the aed and cpr in sequence apply the aed only to pulseless unresponsive patients and do not touch the patient while the aed is analyzing the heart rhythm and delivering shocks and cpr must stop while the aed is delivering the shock aed maintenance is important so become familiar with the maintenance procedures required for the brand of aed that your service uses you want to read the operator's manual three most common errors in using an aed include failure of the machine to shock v-fib applying the aed to a patient who's moving squirming or being transported or turning the aed off before analysis or shock is complete then there's operator errors and the operators errors include failing to apply the aed pads to the patient not pushing the analyze or shock buttons when the machine advises you or pushing the button instead a power button instead of the shock button one hits advise so make sure the battery is properly maintained and check your equipment including your aed daily at the beginning of each shift also ask the manufacturer for checklist of items that should be checked daily weekly or less often report any aed failures that occurs while caring for the patient to the manufacturer and to the us food and drug administration be sure to follow the appropriate ems procedures for notifying these these organizations medical direction should approve the written protocol that you will follow in caring for patients in cardiac arrest the emt team and your services medical director or quality improvement officer should review each incident in which the aed is used quality improvement involves both the individuals using the aed and responsible ems system managers the review should focus on speed of defibrillation shocks should be delivered within one minute of the call and mandatory continuing education with skill competency review is generally required for ems providers so emergency medical care for cardiac arrest so let's talk about this so when preparing to use the aed it's the emt's job to make sure that the electric electricity from the aed injures no one do not defibrillate patients in pooled water electricity will diffuse through the pooled water you can defibrillate a soaking patient but dry the patient's chest first and do not defibrillate patients who are touching metal that others are touching okay we're also going to carefully remove nitro patches from the patient's chest and we're going to wipe the area with a dry towel before we defibrillate to prevent ignition of the patch it's it is often helpful to shave a hairy patient's chest before the placement uh to increase conductivity we're going to determine the patient's nature of illness or mechanism of injury because we might need to perform spinal mobilization for trauma patients during the primary assessment we're going to call for advanced life support assistance in if in a tiered system with a patient in cardiac arrest and use a well-organized team approach so on the figure on this slide displays the aed algorithm and cpr indicates cardiopulmonary resuscitation if you witness a patient in cardiac arrest begin cpr starting the with chest compressions and attach the aed as soon as it is available so you can see the skill drill for the steps using the aed follow local protocols for patient care following aed use after the aed protocol is completed one of the following will likely occur so you'll have pulse which is regained and that's called rosk and brass stands for return of spontaneous circulation or rosc there's no pulse and the aed indicates no shock is advised or no pulse and the aed indicates that the shock is advised if advanced advanced life support is responding to the scene stay where you are and continue the sequence of shocks and cpr if advanced life support is not responding to the scene and protocols agree begin transporting with one of the following the patient regains a pulse six to nine shocks are delivered where the machine gives you three consistent messages separated by two minutes of cpr that no shock is advised okay if you have cardiac arrest during transport if you're traveling to the hospital and an unconscious patient with an unconscious patient and the patient becomes pulseless immediately stop the vehicle you want to begin cpr if the aed is not immediately ready then we're going to call for advanced life support and other available resources based on the circumstances we need to analyze a rhythm deliver the shock if indicated and immediately resume cpr continue resuscitation according to your local protocol if you're in route with a conscious patient who is having chest pain and becomes unconscious of course check the pulse stop the vehicle begin cpr analyze a rhythm deliver the shock begin chest compressions and continue resuscitation according to your local protocol including transporting to the hospital you want to coordinate with advanced life support personnel according to your local protocol so if you have an aed if it's available do not wait for paramedics to arrive notify advanced life support personnel as soon as possible after you recognize a cardiac arrest you do not want to delay defibrillation when paramedics arrive inform them of your actions to the point and then interact with them according to your local protocols okay so this is going to next we're going to talk about rosk and that's return of spontaneous circulation so when you achieve ross we're going to monitor spontaneous respirations we're going to provide oxygen via bag valve mask at 10 breaths a minute we're going to maintain oxygen sets between 95 and 99 assess the patient's blood pressure and see if the patient can follow simple commands if advanced life support is not on scene or in route immediately begin transport to the closest appropriate hospital depending on local protocols okay so that concludes chapter 17 cardiovascular emergencies next we're going to go through the review questions to see how much we've learned okay all of the following are common signs and symptoms of cardiac ischemia except all right so i'm pretty sure it's headache usually if you have cardiac ischemia it's the heart's demand for oxygen you could have shortness of breath or chest pain but a headache is not usually a common sign okay when palpating the radial pulse of a 56 year old man you note that the pulse rate is 86 beats per minute and irregular so what do you think this indicates i'm pretty sure it's going to say dysrhythmia because we know arrhythmias or arrhythmias are regular and dysrhythmia is irregular stands for irregular okay 56 year old man is having a acute myocardial infarc which of the falling blood vessels have become blocked and we know that the um uh the arteries are the the things that deliver blood to places oxygenated blood so it's going to be an artery and we know that the coronary arteries in general are the ones that uh give the blood to the myocardium okay so the coronary arteries major controllable risk factors of an acute myocardial infarction and so these are factors we could control we can't control our age or our history and we can't control the fact of if we're male or female and so it's going to be cigarette smoke okay a patient with cardiac arrest secondary um fib has the greatest chance of survival and we know v fib we need to defib and so um we're going to d fib it's provided within two minutes v fib always want to defib okay 59 year old woman presents with chest pressure she's conscious and alert but her skin's pale cool and clammy your first step in providing care should be all right so our first step when we see that color i think they're probably going to want us to do i think oxygen right yep oxygen so that right really far up in that uh is going to be oxygen in our assessment okay if a patient with an implanted pacemaker is in cardiac arrest you should we're just not going to put the pads on the pacemaker i'm pretty sure yeah and so the only modification we're going to do is we're just not going to put the pads on the implanted pacemaker the main advantage of an aed is all right we're going to get the shocks there it's it is easier than performing cpr and there's no need for advanced life support to be there so i think d all of the above after administering nitro tablet to patient you should so we should check the expiration prior to um we're going to reassess the blood pressure we're going to we're not going to choose a tablet because we're going to put it under the tongue and we should have checked that prescription before so i think it's going to be b yep every five minutes okay and finally nitro is contra indicated in patients well right there right in front of us it's going to be systolic pressure less than 100 millimeters of mercury okay thank you so much for joining me for chapter 17 chest pain lecture if you like this lecture go ahead and subscribe to the channel because we're going to be putting out all of the chapters in the care in emergency care and transportation of the sick and injured 12th edition okay thank you