Cardiac Emergencies
There are many problems that can occur with the cardiovascular system and a wide range of signs and symptoms as well. Cardiac compromise refers to any kind of heart problem. Patients may complain of chest pain, flu-like symptoms, or dyspnea(difficulty breathing). The most common complaint is chest pain. The pain may radiate down an arm with the left arm more commonly involved.
If a patient complains of anything that may suggest cardiac compromise, a focused history and physical exam should be performed. The history should include OPQRST questions. A SAMPLE history should also be obtained followed by baseline vitals. The following signs and symptoms are often associated with cardiac compromise:
- Pain, pressure, or discomfort in the chest or upper abdomen (epigastrium)
- Dyspnea
- Palpitation
- Sudden onset of sweating and nausea or vomiting
- Anxiety (feeling of impending doom)
- Abnormal pulse
- Abnormal blood pressure
The following steps must be following in providing emergency care of patients with cardiac compromise:
- place patient in comfortable position (usually sitting).
- apply high concentration oxygen through a nonrebreather mask.
- transport immediately if the patient exhibits any of the following:
- No history of cardiac problems
- History of cardiac problems but, has no nitroglycerin
- Systolic blood pressure less than 100
4. Give the patient (or help administer) nitroglycerin (sublingually) if all the following conditions are met:
- Chest pain
- History of cardiac problems
- Patient prescribed nitroglycerin
- Patient has nitroglycerin with them
- Systolic blood pressure is greater than 100
- Medical direction authorizes administration
5. Repeat dose in five minutes if all of the following conditions are met:
- Patient experiences no relief
- Systolic blood pressure remains greater than 100
- Medical direction authorizes another dose
A maximum three doses of nitroglycerin may be administered. If blood pressure falls below 100 systolic, treat for shock (hypoperfusion). Nitroglycerin is contraindicated if the patient has hypotension or a systolic blood pressure below 100, has a head injury, or is a child or infant. With infants and children, cardiac conditions are usually congenital so, obtain history from parents if at all possible.
Cardiovascular Disorders
The majority of cardiovascular disorders are caused, directly or indirectly, by changes in the arterial walls. Atherosclerosis is a buildup of fatty deposits on the inner walls of arteries. Other materials combine with fats to form the deposits which is called plaque. Over time, calcium may be deposited in the plaque, causing the deposits to harden. Arteriosclerosis is a stiffening or hardening of the artery wall resulting from the calcium deposits. This leads to increased blood pressure. A blood clot (thrombus) can form along plaque and, if large enough in size or numbers, can cause occlusion of the blood vessel. The clot may break off (embolus) and become lodged in a smaller blood vessel creating an occlusion elsewhere.
Disease that affects the arteries of the heart are referred to coronary artery disease (CAD). Reduced blood flow to the myocardium is the major cause of cardiac emergencies. The most common symptom is chest pain (angina pectoris).
Malfunction of the heart's electrical system results in arrythmias (absent heart beat), or dysrhythmias (irregular heart beats). Tachycardia occurs when the heart rate is above 100 beats per minute. A heart rate below 60 beats per minute is referred to as bradycardia. A heart attack is when a portion of the heart muscle dies due to lack of blood supply. This is called acute myocardial infarction (AMI). When the heart stops functioning altogether, this is called cardiac arrest. When the heart cannot function properly, this is called heart failure. Fluids build up in the lungs and/or other organs because the heart cannot pump adequately. Congestive heart failure (CHF) is heart failure due to the buildup of fluids which is caused by inadequate functioning of the heart but, the fluids also further reduce the functioning of the heart and other organs. Congestive heart failure may be brought on by COPD, heart disease, or hypertension. It may also be a complication of AMI. CHF usually progresses as follows:
- AMI
- pulmonary edema (fluid buildup in the lungs)
- left heart failure
- right heart failure
Fluid accumulation in the feet is called pedal edema.
The signs and symptoms of CHF include:
- tachycardia
- dyspnea
- normal or elevated blood pressure
- cyanosis
- diaphoresis
- pulmonary edema
- anxiety or confusion secondary to hypoxia
- pedal edema
- engorged, pulsating neck veins (late signs)
- enlarged liver and spleen; abdominal distention (late signs)
The chain of survival for cardiac arrest is:
- early access of EMS
- early CPR
- early defibrillation
- early advanced care
Defibrillation can be accomplished two ways: manual and automated defibrillation. With manual defibrillation, the operator must read the ECG on a screen and then decide if the rhythm observed is shockable. With automated external defibrillators, a computer analyzes the rhythm and delivers the appropriate shock if the rhythm is shockable. The most popular defibrillators are the semiautomatic external defibrillators. These have a button that is pressed by the operator to deploy the shock to the patient. The most common conditions that result in cardiac arrest and are shockable are: ventricular fibrillation (v-fib) and ventricular tachycardia (v-tach). Nonshockable rhythms include: pulseless electrical activity (PEA) and asystole. PEA is different from asystole in that the electrical activity is basically normal but there is no pumping action of the heart. It may mean that the myocardium is severely sick or that there has been so much blood loss that there is no fluid to pump. With asystole, there is no electrical activity at all.
Coordinating CPR with AED
- stop CPR to verify no pulse and no breathing (apnea).
- resume CPR and perform focused history and exam. Get SAMPLE history if possible. Do not slow down process of preparing patient for AED.
- Connect white cable to electrode pad placed in the angle between the sternum and the right clavicle. (Think "white is right" and/or "white is heaven" to remember placement.) Connect black cable to electrode pad on the left side exactly as placed for white cable. Connect the red cable to the electrode pad positioned over the left lower ribs. (Think "red is for the devil down below.")
- Clear the patient and wait for AED response.
- If "deliver shock" message, press button to deliver shock and then press analyze button if necessary to determine if additional shock is advised.
- If necessary, give up to three stacked shocks and then check carotid pulse.
- If the patient has a pulse, check breathing then:
(a) if breathing adequately, give high concentration oxygen by nonrebreather mask and transport.
(b) if beathing inadequately, provide artificial ventilation with high concentration oxygen and transport.
- If the patient does NOT have a pulse, resume CPR for 1 minute
- repeat a cycle of three stacked shocks.
- transport the patient if any one of the following occurs:
(a) patient regains a pulse or get a no shock advisory
(b) six shocks have been delivered
(c) AED gives 3 consecutive no shock messages separated by 1 minute of CPR.
If a patient goes back into cardiac arrest:
- stop the vehicle
- start CPR while AED is prepared by another EMT
- analyze rhythm
- deliver shock if indicated
- continue with 2 sets of 3 stacked shocks separated by 1 minute of CPR
Apply an AED only to adults who are in cardiac arrest and have not suffered trauma prior to collapse. Do not use an AED on persons under 8 years of age or trauma victims. Trauma patients usually suffer from blood loss and don't often have a shockable rhythm. Focus should be on preventing blood loss moreso than on heart rhythm.
Review Questions:
1. What position is best for a patient with: (a) dyspnea and bp of 110/70 , and (b) chest pain and a bp of 180/90?
2. How would you transport a patient down a stairs with dyspnea, chest pressure, and a bp of 160/100?
3. How do you "clear" a patient before delivering a shock?
4. What are three safety measures to remember when using an AED?
5. What are the steps in using an AED?
6. A progressive condition that causes poor blood flow to the heart by blocking coronary arteries with calcium and fat deposits is called_____.
7. What is the major difference between angina pectoris and myocardial infarction?
8. What is tachycardia?
9. What is bradycardia?
10. Your female patient is 67-years old and complains of chest pain that occurred at rest. The duration of the pain has been approximately 45 minutes and she has no relief with her medications. Chest pain of this type is indicative of what?
11. Which of the following would be most effective in the first few minutes of treatment of the cardiac arrest patient?
CPR
AED rhythm analysis
ventilation
transport
12. What cardiac rhythm would yield a shock advised message when producing a pulse?
13. When would you consider transporting a patient who is being treated with AED and CPR?
14. What do you do regarding CPR during the analyze mode of an AED?
15. What is the rationale for delivering three shocks in rapid succession from an AED without a pulse check between shocks?
16. What do you do if transporting a patient complaining of chest pain who becomes unconscious and has no pulse?
17. What do you do if, after the AED has delivered three successive shocks and a pulse returns but, the patient is still unconscious?
18. How would you use an AED on a 6 year old drowning victim that has no pulse?
19. What are common side effects from administration of nitroglycerin?
20. What are the contraindications for administration of nitroglycerin?