Overview. Overview. Chapter 19. Cardiovascular Emergencies 9/11/2012. Review of the Circulatory System. Cardiac Compromise

Transcription

1 Chapter 19 Cardiovascular Emergencies Slide 1 Overview Review of the Circulatory System Anatomy Physiology Cardiac Compromise Assessment Emergency Medical Care Slide 2 Overview Automated External Defibrillator Overview of the Automated External Defibrillator Advantages of the Automated External Defibrillator Operation of the Automated External Defibrillator Postresuscitation Care Automated External Defibrillator Maintenance Automated External Defibrillator Skills Slide 3 1

2 The Circulatory System Slide 4 The Circulatory System The heart pumps blood to the body organs through the cardiovascular system This process is so vital to life that any interruption for more than a few minutes can mean death to the individual Slide 5 The Circulatory System Heart Blood vessels Arteries Veins Capillaries Blood Slide 6 2

3 Structure and function The Heart Atrium Right Receives blood from the veins of the body and the heart Pumps oxygen-poor blood to the right ventricle Left Receives blood from the pulmonary veins (lungs) Pumps oxygen-rich blood to left ventricle Ventricle Right Receives blood from the right atrium Pumps oxygen-poor blood to the lungs Left Receives blood from the left atrium Pumps oxygen-rich blood to the body Slide 7 The Heart Slide 8 The Heart Structure and function Valves prevent backflow of blood Slide 9 3

4 The Heart Structure and function Cardiac conductive system Heart is more than a muscle Specialized contractile and conductive tissue in the heart Electrical impulses create coordinated contraction Automaticity The ability of cardiac muscle cells to generate their own impulses Slide 10 Arteries Blood Vessels Arterioles Capillaries Venules Veins Slide 11 Arteries Carry blood away from the heart to the rest of the body Major arteries Coronary Vessels that supply the heart with blood Aorta Major artery originating from the heart, lying in front of the spine in the thoracic and abdominal cavities Pulmonary Artery originating at the right ventricle; carries oxygen-poor blood to the lungs Carotid Major artery of the neck Femoral Major artery of the thigh Radial Major artery of the lower arm Brachial An artery of the upper arm Posterior tibial Dorsalis pedis Slide 12 4

5 Arteries Slide 13 Arterioles The smallest branches of an artery leading to the capillaries Slide 14 Capillaries Tiny blood vessels that connect arterioles to venules Found in all parts of the body Allow for the exchange of nutrients and waste at the cellular level Slide 15 5

6 Capillaries Slide 16 Venules The smallest branches of a vein leading to the capillaries Slide 17 Veins Vessels that carry blood back to the heart Major veins Pulmonary vein Carries oxygen-rich blood from the lungs to the left atrium Venae cavae Superior Inferior Carries oxygen-poor blood back to the right atrium Slide 18 6

7 Veins Slide 19 The Blood Red blood cells Give the blood its color Carry oxygen to organs Carry carbon dioxide away from organs White blood cells Part of the body s defense against infections Plasma Fluid that carries the blood cells and nutrients Platelets Essential for the formation of blood clots Slide 20 Pulse Left ventricle contracts, sending a wave of blood through the arteries Can be palpated anywhere an artery simultaneously passes near the skin surface and over a bone Peripheral Radial Brachial Posterior tibial Dorsalis pedis Central Carotid Femoral Slide 21 7

8 Pulse Slide 22 Blood Pressure A measure of the pressure exerted against the walls of the arteries during contraction and relaxation of the heart Systolic Pressure exerted against the walls of the artery when the left ventricle contracts Diastolic Pressure exerted against the walls of the artery when the left ventricle is at rest Slide 23 Perfusion The process of delivering oxygenated blood to the organs and removing waste products and carbon dioxide Cellular respiration Slide 24 8

9 Perfusion Shock (hypoperfusion) Widespread inadequate tissue perfusion Slide 25 Shock Signs and symptoms Pale or cyanotic skin Cool or cold skin Rapid weak pulse Altered mental status Rapid breathing Nausea and vomiting Low or decreasing blood pressure A LATE SIGN! Slide 26 Cardiac Compromise Slide 27 9

10 Cardiac Compromise Ischemia A condition of reduced oxygen to body tissues and cells Slide 28 Cardiac Compromise Atherosclerosis A condition in which cholesterol and cellular debris form a plaque inside the arteries, narrowing the area that the blood flows through Slide 29 Cardiac Compromise Normal artery Artery clogged with plaque Slide 30 10

11 Cardiac Compromise Angina Chest pain caused by reduced oxygen to the heart due to inadequate blood supply through the coronary arteries Slide 31 Cardiac Compromise Myocardial infarction A condition in which a part of the heart muscle dies as a result of no blood supply and prolonged lack of oxygen Slide 32 Cardiac Compromise Myocardial Infarction Slide 33 11

12 Cardiac Compromise Congestive heart failure A condition in which the heart fails to pump efficiently, causing fluid to back up into the lungs and venous system Slide 34 Cardiac Compromise Signs and symptoms Squeezing, dull pressure; chest pain commonly radiating down the arms or to the jaw Sudden onset of sweating (this in and of itself is a significant finding) Difficulty breathing (dyspnea) Anxiety, irritability Feeling of impending doom Abnormal pulse rate (may be irregular) Abnormal blood pressure Epigastric pain Nausea/vomiting Slide 35 Assessment Initial assessment Focused history and physical exam OPQRST Physical exam SAMPLE history Slide 36 12

13 Emergency Medical Care Slide 37 Emergency Medical Care Priorities in management Oxygen Positioning Nitroglycerin Basic life support Slide 38 Emergency Medical Care Place the patient in a position of comfort Administer high-flow oxygen Slide 39 13

14 Emergency Medical Care Administration of nitroglycerin reduces the workload of the heart Slide 40 Nitroglycerin Indications Signs and symptoms of cardiac chest pain Patient has physician-prescribed nitroglycerin spray or sublingual tablets EMT-B has permission from medical direction physician Slide 41 Nitroglycerin Contraindications Patient has systolic blood pressure less than 100 mm Hg Patient does not have own nitroglycerin Patient has head injury or is not mentally alert Patient has already taken maximum prescribed dosage Patient has taken an erectile dysfunction medication within the past hours Slide 42 14

15 Nitroglycerin Assisting the patient with nitroglycerin Obtain order from medical direction either online or offline Perform focused assessment for cardiac patient Take blood pressure above 100 mm Hg systolic Contact medical control if no standing orders Slide 43 Nitroglycerin Assisting the patient with nitroglycerin Ensure right medication, right patient, right route, patient alert Check expiration date of nitroglycerin Question patient on last dose, administration, effects, and ensure understanding of route of administration Ask patient to lift tongue and place tablet or spray dose under tongue (while wearing gloves) or have patient place tablet or spray under tongue Slide 44 Nitroglycerin Assisting with nitroglycerin Have patient keep mouth closed with tablet under tongue (without swallowing) until dissolved and absorbed Recheck blood pressure within 2 minutes Record activity and time Perform reassessment Slide 45 15

16 Nitroglycerin Assisting with nitroglycerin Reassessment strategies Monitor blood pressure Ask patient about effect on pain relief Seek medical direction before readministering Record reassessments Slide 46 Video Clip: Administration of Nitroglycerin Slide 47 Nitroglycerin Mechanism of action Relaxes vascular smooth muscle to increase coronary blood flow Decreases blood return to heart, thus lessens heart s workload Slide 48 16

17 Nitroglycerin Side effects Lowers blood pressure Headache Pulse rate may drop Burning sensation on or under tongue Slide 49 Basic Life Support Review If available, request ALS backup One-person CPR Two-person CPR Slide 50 Automated External Defibrillation Slide 51 17

18 Automated External Defibrillation Defibrillation is the primary intervention that makes the greatest difference in survival of cardiac arrest patients in ventricular fibrillation. Slide 52 Automated External Defibrillation The chain of survival Slide 53 Automated External Defibrillation Many EMS systems have demonstrated increased survival outcomes of cardiac arrest patients experiencing ventricular fibrillation This increased survival was after early defibrillation programs were implemented and when all of the links in the chain of survival were present Slide 54 18

19 Automated External Defibrillation Analysis of cardiac rhythms Defibrillator computer microprocessor evaluates the patient s rhythm and confirms the presence of a rhythm for which a shock is indicated Detects shockable rhythms Slide 55 Automated External Defibrillation Ventricular fibrillation Slide 56 Automated External Defibrillation Ventricular tachycardia Slide 57 19

20 Automated External Defibrillation Overview of automated external defibrillators Types of automated external defibrillators Fully automated defibrillator operates without action by EMT-Basic, except to turn on power Semiautomated defibrillator uses a computer voice synthesizer to advise EMT-Basic as to the steps to take based on its analysis of the patient s cardiac rhythm Slide 58 Automated External Defibrillation Accuracy of devices in rhythm analysis has been high, both in detecting rhythms that need shocks and rhythms that do not need shocks Analysis is dependent on properly charged defibrillator batteries Slide 59 Automated External Defibrillation Inappropriate delivery of shocks Human error Mechanical error Slide 60 20

21 Automated External Defibrillation Attach defibrillator to only unresponsive, pulseless, nonbreathing patients to avoid delivering inappropriate shocks Defibrillator advises shocks for ventricular tachycardia when the rate exceeds a certain value (for example, above 180 beats/min) Slide 61 Automated External Defibrillation Interruption of CPR No CPR performed at times shocks are delivered No person should be touching patient when rhythm is being analyzed and when shocks are delivered Chest compressions and artificial ventilations are stopped when the rhythm is being analyzed and when shocks are delivered Defibrillation is more effective than CPR; stopping CPR during the process is more beneficial to patient outcome CPR may be stopped for up to 90 seconds if three shocks are necessary Resume CPR only after up to the first three shocks are delivered Slide 62 Automated External Defibrillation Advantages Speed of operation Defibrillation is hands off Safer method Better electrode placement Has larger pad surface area Provokes less anxiety in EMT-Basic Slide 63 21

22 Operation of the AED Take infection control precautions en route to scene Arrive on scene and perform initial assessment Stop CPR if in progress Verify pulselessness and apnea Slide 64 Operation of the AED Have partner resume CPR Turn on defibrillator power Slide 65 Operation of the AED Attach device Begin narrative if machine has tape recorder Slide 66 22

23 Operation of the AED Stop CPR Clear patient Initiate analysis of rhythm Slide 67 Operation of the AED Machine advises shock Deliver shock Slide 68 Operation of the AED Slide 69 23

24 Operation of the AED If no ACLS personnel are on scene, transport patient when: Pulse regained Three consecutive messages of no shock advised (separated by 1 minute of CPR) Slide 70 Operation of the AED One EMT operates the AED, and the other EMT performs CPR Open the airway and confirm arrest Defibrillation comes first Do not do anything that delays shocks The first shock should be delivered within 60 seconds Slide 71 Operation of the AED State clear patient before defibrillation Make sure everyone is clear Slide 72 24

25 Operation of the AED En route to receiving facility Continue shocks as long as AED advises Sets of three shocks with 1 minute of CPR between Stop vehicle to analyze the rhythm Additional shocks as directed by medical direction physician Slide 73 Video Clip: Use of an Automatic External Defibrillator Slide 74 Postresuscitation Care After AED protocol is completed, the patient may: Have pulses Have no pulse with machine indicating no shock indicated Have no pulse with machine indicating shock Slide 75 25

26 Postresuscitation Care If pulses return Consider awaiting ALS backup if appropriate Transport the patient Continue to keep defibrillator device on patient en route Perform focused assessment and reassessment en route Slide 76 Defibrillator Maintenance The most common cause of defibrillator failure is poor maintenance Use a maintenance checklist Slide 77 AED Skills Maintenance of AED skills Practice skills regularly Have events reviewed by medical director or representative Slide 78 26

27 Summary Review of the Circulatory System Anatomy Physiology Cardiac Compromise Assessment Emergency Medical Care Slide 79 Summary Automated External Defibrillator Overview of the Automated External Defibrillator Advantages of the Automated External Defibrillator Operation of the Automated External Defibrillator Postresuscitation Care Automated External Defibrillator Maintenance Automated External Defibrillator Skills Slide 80 27