Introduction
Cardiology and resuscitation represent one of the most critical knowledge domains for Emergency Medical Technicians, accounting for 20-24% of the NREMT certification examination. Mastery of cardiovascular emergencies is essential because cardiac events remain among the leading causes of emergency medical calls, and the actions taken by EMTs in the first minutes can mean the difference between life and death. Understanding the anatomy and physiology of the cardiovascular system provides the foundation for recognizing life-threatening conditions such as myocardial infarction, cardiac arrest, and various forms of shock. EMTs must be proficient in performing high-quality cardiopulmonary resuscitation (CPR), operating automated external defibrillators (AEDs), and recognizing when advanced cardiac life support interventions are needed. The ability to quickly assess a patient’s cardiac status, identify signs of inadequate perfusion, and implement appropriate emergency interventions is fundamental to the EMT scope of practice. This topic area integrates patient assessment skills with critical decision-making under pressure, requiring EMTs to prioritize interventions based on the patient’s presenting condition. Knowledge of cardiac medications that patients may be taking, understanding contraindications for assisted medication administration, and recognizing adverse cardiac events are all essential components of competent emergency cardiac care. The questions that follow are designed to test your understanding of cardiovascular anatomy, recognition of cardiac emergencies, proper resuscitation techniques, and the critical thinking skills necessary to manage these high-stakes situations. Proficiency in cardiology and resuscitation not only prepares you for certification success but also equips you with the life-saving skills that define excellence in emergency medical services. Regular practice with scenario-based questions like these will strengthen your ability to make rapid, evidence-based decisions in the field when every second counts.
Practice Questions
Question 1:
A 58-year-old male is complaining of crushing chest pain radiating to his left arm. He is diaphoretic and nauseous. His vital signs are: BP 90/60, pulse 110 and irregular, respirations 22. What is your FIRST priority?
A) Administer aspirin
B) Apply high-flow oxygen
C) Obtain a detailed medical history
D) Prepare for immediate transport
Correct Answer: B) Apply high-flow oxygen
Explanation: While all options are important in managing a suspected myocardial infarction, the ABCs (Airway, Breathing, Circulation) always take priority. With tachypnea (22 respirations per minute) and signs of cardiac compromise, ensuring adequate oxygenation is the first priority. High-flow oxygen via non-rebreather mask should be applied immediately to maximize oxygen delivery to ischemic cardiac tissue. After securing the airway and breathing, you would then address circulation concerns, administer aspirin (if not contraindicated), obtain history, and prepare for transport. The patient’s hypotension and irregular pulse indicate significant cardiac compromise, making oxygen therapy critical before other interventions.
Question 2:
During CPR on an adult patient, what is the correct compression-to-ventilation ratio for a single EMT rescuer?
A) 15:2
B) 30:2
C) 15:1
D) 30:1
Correct Answer: B) 30:2
Explanation: According to current American Heart Association guidelines, the compression-to-ventilation ratio for adult CPR by a single rescuer is 30 compressions to 2 ventilations. This ratio applies whether you are performing one-rescuer or two-rescuer CPR on an adult patient. The 30:2 ratio maximizes chest compressions while still providing adequate ventilation. For pediatric patients with two healthcare providers, the ratio changes to 15:2, but for adults, it remains 30:2 regardless of the number of rescuers. This ratio ensures that interruptions in chest compressions are minimized, as continuous, high-quality compressions are the most critical component of effective CPR.
Question 3:
You arrive on scene to find a 45-year-old female in cardiac arrest. After confirming pulselessness and beginning CPR, when should the AED be applied?
A) After 2 minutes of CPR
B) After 5 cycles of CPR
C) As soon as it is available
D) After establishing an advanced airway
Correct Answer: C) As soon as it is available
Explanation: Early defibrillation is one of the most critical interventions in cardiac arrest management. The AED should be applied as soon as it becomes available, without waiting for a specific number of CPR cycles to be completed. For every minute that defibrillation is delayed in ventricular fibrillation or pulseless ventricular tachycardia, survival rates decrease by approximately 7-10%. While high-quality CPR should not be interrupted for extended periods, the brief pause needed to apply AED pads and analyze the rhythm is justified because early defibrillation is the definitive treatment for shockable rhythms. Once the AED is applied and analyzing, CPR should be resumed immediately after any shock is delivered or if no shock is advised.
Question 4:
A patient’s AED advises “shock advised.” After delivering the shock, what is your next action?
A) Check for a pulse
B) Immediately resume CPR starting with compressions
C) Wait for the AED to reanalyze
D) Deliver a second shock
Correct Answer: B) Immediately resume CPR starting with compressions
Explanation: Current resuscitation guidelines emphasize minimizing interruptions in chest compressions. After delivering a shock, you should immediately resume CPR beginning with chest compressions without checking for a pulse or waiting for the AED to reanalyze. The rationale is that even if the shock successfully converted the rhythm, it takes time for organized cardiac activity to generate a palpable pulse, and the heart muscle benefits from continued perfusion through chest compressions. You should perform 2 minutes (5 cycles) of CPR before the AED prompts you to stop for rhythm reanalysis. Checking for a pulse immediately after a shock wastes valuable time and delays the resumption of compressions, which are critical for maintaining blood flow to vital organs.
Question 5:
Which of the following is a contraindication for assisting a patient with their prescribed nitroglycerin?
A) Blood pressure of 140/90 mmHg
B) Patient took sildenafil (Viagra) 18 hours ago
C) Patient has a history of heart attack
D) Patient rates chest pain as 8/10
Correct Answer: B) Patient took sildenafil (Viagra) 18 hours ago
Explanation: Nitroglycerin is absolutely contraindicated in patients who have taken phosphodiesterase inhibitors (such as sildenafil/Viagra, tadalafil/Cialis, or vardenafil/Levitra) within the past 24-48 hours, depending on the specific medication. The combination can cause severe, potentially fatal hypotension because both medications cause vasodilation. Sildenafil’s effects can last up to 24 hours, making it dangerous to administer nitroglycerin within this timeframe. A blood pressure of 140/90 is actually adequate for nitroglycerin administration (systolic BP should be above 90-100 mmHg). A history of heart attack is not a contraindication—in fact, it makes the current chest pain more concerning. Severe chest pain (8/10) is an indication for nitroglycerin, not a contraindication. Always ask about erectile dysfunction medications before assisting with nitroglycerin.
Question 6:
What is the proper hand placement for chest compressions on an adult patient?
A) Over the upper half of the sternum
B) Over the lower half of the sternum
C) Just below the xiphoid process
D) Over the left side of the chest
Correct Answer: B) Over the lower half of the sternum
Explanation: Proper hand placement for adult chest compressions is on the lower half of the sternum, in the center of the chest. This position allows for optimal compression of the heart between the sternum and the spine, maximizing blood flow during CPR. To locate this position, place the heel of one hand on the center of the chest between the nipples, then place your other hand on top. Compressions over the upper half of the sternum are ineffective and may cause injury. Compressions directly on or below the xiphoid process can cause the xiphoid to break off and lacerate the liver, causing life-threatening internal bleeding. Compressions over the left side of the chest are not centered properly and will be less effective. The lower half of the sternum provides the correct anatomical landmark for safe and effective compressions.
Question 7:
A 72-year-old male is experiencing chest pain. His pulse is 180 beats per minute and regular. He is alert but anxious. What condition should you suspect?
A) Ventricular fibrillation
B) Supraventricular tachycardia
C) Atrial fibrillation
D) Ventricular tachycardia
Correct Answer: B) Supraventricular tachycardia
Explanation: Supraventricular tachycardia (SVT) is characterized by a very rapid but regular heart rate, typically between 150-250 beats per minute, originating above the ventricles. The fact that the patient is alert and has a regular rhythm at 180 bpm strongly suggests SVT. Ventricular fibrillation would present with no pulse and unconsciousness, as it is a lethal rhythm with no organized cardiac output. Atrial fibrillation typically presents with an irregularly irregular rhythm, not a regular one. While ventricular tachycardia can present with a pulse in some cases, it is less common than SVT and typically presents with more severe symptoms and hemodynamic instability. The regular rhythm at this rate is the key distinguishing feature pointing to SVT. Treatment priorities include oxygen, IV access if available in your scope, and rapid transport, as this patient may require medication or electrical cardioversion.
Question 8:
What is the minimum depth for chest compressions on an adult patient?
A) At least 1 inch (2.5 cm)
B) At least 1.5 inches (4 cm)
C) At least 2 inches (5 cm)
D) At least 3 inches (7.5 cm)
Correct Answer: C) At least 2 inches (5 cm)
Explanation: Current American Heart Association guidelines specify that chest compressions on adult patients should be at least 2 inches (5 cm) deep, but not exceeding 2.4 inches (6 cm). This depth is necessary to adequately compress the heart between the sternum and spine, generating sufficient blood flow to vital organs. Compressions that are too shallow (less than 2 inches) are ineffective and fail to produce adequate circulation. However, compressions deeper than 2.4 inches may cause injuries such as rib fractures, sternal fractures, or internal organ damage. The rate should be 100-120 compressions per minute, and you should allow complete chest recoil between compressions. High-quality CPR with adequate compression depth is one of the most important factors in improving survival from cardiac arrest. Using a feedback device or having another rescuer observe compression depth can help ensure you’re meeting this critical standard.
Question 9:
A patient in cardiac arrest has been in ventricular fibrillation for several minutes. The AED has delivered three shocks without success. What should you do?
A) Continue CPR and transport immediately
B) Deliver additional shocks every 30 seconds
C) Stop resuscitation efforts
D) Switch to manual defibrillation
Correct Answer: A) Continue CPR and transport immediately
Explanation: When a patient remains in ventricular fibrillation after multiple defibrillation attempts, the priority is to continue high-quality CPR and transport to a facility where advanced cardiac life support (ACLS) can be provided. The AED will continue to analyze the rhythm every 2 minutes and advise additional shocks if appropriate. Continuous CPR maintains some blood flow to the heart and brain, improving the chances that subsequent shocks will be successful and that the patient can survive until receiving advanced interventions such as medications (epinephrine, amiodarone) and advanced airway management. Delivering shocks more frequently than the AED recommends is not appropriate and interrupts CPR unnecessarily. Stopping resuscitation after three shocks is premature—resuscitation should continue unless there are signs of obvious death, a valid DNR order, or the scene becomes unsafe. Manual defibrillation is not within the EMT scope of practice. Transport should not be delayed for extended on-scene resuscitation unless there are special circumstances.
Question 10:
Which of the following signs would indicate adequate perfusion in a cardiac patient?
A) Capillary refill of 4 seconds
B) Pale, cool, clammy skin
C) Strong, regular radial pulse
D) Altered mental status
Correct Answer: C) Strong, regular radial pulse
Explanation: A strong, regular radial pulse is an excellent indicator of adequate perfusion, as it demonstrates that the heart is generating sufficient pressure to deliver blood to the peripheral circulation. The presence of radial pulses generally indicates a systolic blood pressure of at least 80-90 mmHg. Capillary refill of 4 seconds is abnormal (normal is less than 2 seconds) and indicates poor perfusion. Pale, cool, clammy skin suggests poor perfusion and possible shock, as the body is shunting blood away from the skin to preserve vital organs. Altered mental status indicates inadequate perfusion to the brain, which is one of the most sensitive indicators of shock. Other signs of adequate perfusion include normal mental status, warm and dry skin with normal color, capillary refill less than 2 seconds, and adequate urine output (though this is not typically assessed in the prehospital setting). When assessing perfusion, always consider multiple factors together rather than relying on a single sign.
Question 11:
A 55-year-old female is complaining of chest pain. She has a history of angina and has already taken two of her prescribed nitroglycerin tablets without relief. Her blood pressure is 108/70. What should you do?
A) Assist her with a third nitroglycerin tablet
B) Withhold nitroglycerin and transport immediately
C) Have her take all remaining nitroglycerin tablets
D) Wait 10 minutes before considering more nitroglycerin
Correct Answer: A) Assist her with a third nitroglycerin tablet
Explanation: Patients with prescribed nitroglycerin can typically take up to three doses, spaced 3-5 minutes apart, for chest pain. Since this patient has taken two doses without relief and her blood pressure is adequate (systolic above 100 mmHg), assisting with a third dose is appropriate before transport. Nitroglycerin is a vasodilator that reduces cardiac workload and can relieve chest pain from angina or myocardial infarction. However, after three doses without relief, no additional nitroglycerin should be given, and the patient should be transported immediately as this suggests a more serious cardiac event that requires advanced care. Withholding the third dose would be premature since she meets the criteria for administration. Having her take all remaining tablets would be dangerous and could cause severe hypotension. The standard interval between doses is 3-5 minutes, not 10 minutes. Always reassess blood pressure before each dose, as nitroglycerin can cause significant drops in blood pressure.
Question 12:
What is the primary purpose of chest compressions during CPR?
A) To restart the heart’s electrical activity
B) To manually pump blood through the circulatory system
C) To stimulate breathing
D) To prevent blood clots from forming
Correct Answer: B) To manually pump blood through the circulatory system
Explanation: The primary purpose of chest compressions is to manually pump blood through the circulatory system, maintaining some blood flow to vital organs (particularly the brain and heart) when the heart is not beating effectively on its own. By compressing the chest, you increase intrathoracic pressure and physically squeeze the heart between the sternum and spine, forcing blood out into the circulation. When you release, the chest recoils and blood returns to the heart. This creates artificial circulation that can sustain life temporarily until the heart’s normal rhythm can be restored. Chest compressions do not restart the heart’s electrical activity—that’s the purpose of defibrillation. While adequate circulation supports all body functions including respiration at the cellular level, compressions do not directly stimulate breathing. Preventing blood clots is not a primary goal of CPR. High-quality compressions at the correct rate, depth, and with complete recoil are essential for generating adequate blood flow during cardiac arrest.
Question 13:
A patient is in cardiac arrest. You notice the AED pads are not adhering well due to excessive chest hair. What should you do?
A) Press the pads down firmly and proceed
B) Shave the chest with a razor before applying pads
C) Use the first set of pads to remove hair, then apply a new set
D) Place the pads on the patient’s back instead
Correct Answer: C) Use the first set of pads to remove hair, then apply a new set
Explanation: When excessive chest hair prevents proper AED pad adhesion, the fastest and most effective method is to use the first set of pads to quickly remove the hair by pressing them down firmly and then ripping them off quickly (like a wax strip). Then immediately apply a new set of pads to the now-hair-free skin. This technique is faster than shaving and ensures good pad contact for effective defibrillation. Simply pressing the pads down firmly on hairy skin will not provide adequate contact and may result in ineffective shock delivery or skin burns. Shaving takes too much time and delays defibrillation, which is critical in cardiac arrest. Placing pads on the back is not a standard pad placement for AED use (though anterior-posterior placement can be used in specific situations, it’s not the solution for chest hair). Most AED kits include two sets of pads for this reason. Minimizing the delay to first shock is critical for survival.
Question 14:
Which of the following patients would be appropriate for AED use?
A) A 6-month-old infant in cardiac arrest
B) A patient who is unresponsive but has a pulse
C) A patient lying in a large puddle of water
D) An 8-year-old child in cardiac arrest
Correct Answer: D) An 8-year-old child in cardiac arrest
Explanation: An 8-year-old child in cardiac arrest is appropriate for AED use. For children ages 1-8, pediatric pads or a pediatric dose attenuator should be used if available, but if not available, adult pads can be used. For infants under 1 year old, a manual defibrillator is preferred, but if unavailable, an AED with pediatric pads can be used as a last resort. A patient who is unresponsive but has a pulse should not receive defibrillation—the AED is only for pulseless patients in cardiac arrest. A patient lying in a large puddle of water should be moved to a dry area before AED application to prevent shock to rescuers and ensure effective defibrillation. Water is an excellent conductor of electricity, and attempting to defibrillate in standing water could result in the shock being conducted away from the heart or shocking the rescuers. Always ensure the patient is on a dry surface, remove wet clothing from the chest, and dry the chest before applying AED pads.
Question 15:
A 60-year-old male is experiencing chest pain. He tells you he has a nitroglycerin prescription but left it at home. What should you do?
A) Contact medical control to request permission to give him your nitroglycerin
B) Transport without nitroglycerin administration
C) Stop at a pharmacy to get his prescription
D) Borrow nitroglycerin from another patient on scene
Correct Answer: B) Transport without nitroglycerin administration
Explanation: EMTs can only assist patients with their own prescribed medications. You cannot administer your personal nitroglycerin, borrow medication from another patient, or give any medication that is not specifically prescribed to the patient you are treating. This is both a legal requirement and a safety issue—medications are prescribed based on individual patient conditions, and giving medication prescribed to someone else could be dangerous. While some EMS systems allow paramedics to administer nitroglycerin from their own stock under medical control, this is not within the basic EMT scope of practice in most jurisdictions. The appropriate action is to provide supportive care (oxygen, position of comfort, monitoring), transport promptly to the hospital where the patient can receive appropriate cardiac medications, and notify the receiving facility of the patient’s condition. Stopping at a pharmacy would cause a dangerous delay in definitive care. Always follow your local protocols regarding medication assistance, but the general principle is that you can only assist with medications prescribed to and possessed by the patient.