CCT - Practice Test With Complete Solutions Latest Update, Exams of Nursing

Download CCT - Practice Test With Complete Solutions Latest Update and more Exams Nursing in PDF only on Docsity! CCT - Practice Test With Complete Solutions Latest Update 1. Which heart chamber functions to pump deoxygenated blood to the lungs? a. Right atrium b. Right ventricle c. Left atrium d. Left ventricle - correct answers 1. B: The right ventricle pumps the deoxygenated blood it has received from the right atrium to the lungs. The right atrium pumps deoxygenated blood from the body to the right ventricle. The left atrium pumps oxygenated blood from the lungs to the left ventricle. The left ventricle pumps oxygenated blood to the body. 2. Which lead is the most affected by respiration? a. V2 b. V4 c. Lead III d. Lead I - correct answers 2. C: Lead III is the most affected by respiration, and therefore the waveforms may look different depending on the respiratory cycle. Because of this, a Q wave that only appears in lead III and is not associated with other corresponding changes in other leads is not significant. 3. Which of the following is the correct sequence by which action potentials are conducted through the heart?" a. SA node → AV node → bundle branches → Purkinje fibers b. Bundle branches → Purkinje fibers → SA node → AV node c. Purkinje fibers → SA node → bundle branches → AV node d. AV node → SA node → bundle branches → Purkinje fibers - correct answers 3. A: The sequence by which an action potential is conducted through the heart is from the sinoatrial (SA) node to the atrioventricular (AV) node to the bundle branches and then to the Purkinje fibers. 4. What type of heart block is seen in the following electrocardiogram (ECG) strip?" a. First-degree heart block b. Second-degree heart block, type 1 c. Second-degree heart block, type 2 d. Third-degree heart block - correct answers 4. B: The pictured ECG is a second-degree heart block, type 1. This rhythm is also called Mobitz I or Wenckebach. With this heart block the PR interval gets longer with each beat until eventually a P wave occurs, but a QRS does not follow (a beat is skipped). After the skipped beat, the rapid decrease in the sodium current. Phase 2 is a plateau phase during which "late" calcium, and to a lesser extent sodium, currents offset the effect of potassium currents and temporarily stabilize the membrane potential. Phase 3 refers to repolarization and return to resting potential due to increased potassium currents. Phase 4 is the resting membrane potential. 8. The depolarizing current in pacemaker cells is created primarily by which of the following ions? a. Sodium b. Calcium c. Potassium d. Chloride - correct answers 8. B: The depolarizing current in cardiac pacemaker cells is carried primarily by relatively slow, inward calcium currents. In most other depolarizing cells, such as muscle cells, the depolarization is created by fast sodium currents. Potassium plays a role in repolarization of the cells. 9. Which of the following commonly limits the diagnostic value of Holter monitoring? a. Patient noncompliance with keeping track of events b. Lack of continuous monitoring c. Small capacity of recording devices d. Transmission of data depends on patient participation - correct answers 9. A: Patient noncompliance with keeping a diary of their symptoms and using event markers significantly limits the diagnostic value of Holter monitoring. It is important for patients to record and mark their symptoms in order to correlate events with the data collected. Holter monitoring is a type of continuous monitoring and benefits include the large capacity of the recording devices as well as the ability to transmit data without patient participation. 10. Which of the following effects is caused by the actions of the parasympathetic nervous system on the heart? a. Increased rate of conduction b. Greater force of contraction c. Decreased diastolic filling time d. Decreased rate of SA node pacing - correct answers 10. D: The parasympathetic nervous system results in cardiac inhibitory effects, including decreased rate of SA node pacing, decreased rate of conduction, and decreased force of contraction. The sympathetic nervous system increases the rate of conduction and causes increased force of contraction. An increased contraction rate, caused by sympathetic nervous system stimulation, would result in decreased diastolic filling time. 11. What does the T wave represent on an ECG? a. Atrial depolarization b. Ventricular depolarization c. Atrial repolarization d. Ventricular repolarization - correct answers 11. D: Repolarization of the ventricles begins immediately after the QRS. The T wave represents the final and more rapid phase of that repolarization. Atrial depolarization is represented by the P wave. Ventricular depolarization is represented by the QRS complex. Atrial repolarization is not seen on the ECG. 12. What benefit does a thallium stress test have as compared to a standard ECG stress test? a. More quickly identifies areas of myocardial ischemia in the heart b. The test is simpler to perform c. More accurately identifies the specific areas of reduced blood flow in the heart d. Is a safer test overall for the patient - correct answers 12. C: Thallium stress tests, also known as nuclear stress tests, gather more specific and accurate information than simple ECG stress tests. It is a helpful test when trying to identify the severity of coronary artery disease in a patient with known coronary disease. 13. Which of the following is the correct placement of chest leads for a 12-lead ECG? a. V1 in the third intercostal space, immediately right of the sternum. V2 in the fourth intercostal space, immediately left of the sternum. V3 midway between V2 d. Heart block - correct answers 16. A: These spikes are an artifact due to the firing of an implanted pacemaker. In the above ECG the pacemaker is firing at regular intervals and each spike is followed by a QRS complex and a T wave. This is a normal ECG for a patient with a firing implanted pacemaker. 17. Which of the following is NOT an indication for Holter monitoring? a. Assessing pacemaker function b. Evaluating syncopal episodes c. Assessing for ischemia d. Evaluating for a new infarction - correct answers 17. D: Holter (ambulatory) ECG monitoring can be useful in evaluating cardiac rhythm abnormalities, assessing pacemaker and implantable defibrillator function, assessing for ischemia, and evaluating heart rate variability. Ambulatory ECGs can be used to rule out conditions that may be missed on routine ECGs. Evaluation for an infarction should be done as an inpatient care since this requires immediate treatment if a new infarction is present. 18. What is the difference between the first stage of the "Bruce protocol" stress test and the first stage of the "Modified Bruce protocol" stress test? a. The Modified Bruce protocol starts at the same gradient, but at a slower speed for the first stage of the test. b. The Modified Bruce protocol starts at the same speed, but at a lower gradient for the first stage of the test. c. The Modified Bruce protocol starts at a lower gradient and a slower speed for the first stage of the test. d. There is no difference between the first stage of the two protocols. - correct answers 18. B: Stage 1 of the Bruce protocol is a speed of 1.7 mph and gradient of 10%; stage 2 is a speed of 2.5 mph and a gradient of 12%. Stage 1 of the Modified Bruce protocol is a speed of 1.7 mph and a gradient of 0%; stage 2 is a speed of 1.7 mph and a 5% grade. The third stage of the Modified Bruce protocol corresponds to the first stage of the standard Bruce protocol and continues on from there. The Modified Bruce protocol is typically used for elderly or sedentary patients. 19. A patient is found to have a normal heart rate and rhythm. It is determined from an ECG that the axis of the heart is -35°. What does this indicate? a. The heart is in its normal axis range b. The patient has vertical axis deviation c. The patient has right axis deviation d. The patient has left axis deviation - correct answers 19. D: The normal axis of the heart is between 0° and +90°, which is downwards and to the left. If the axis is upwards and to the left (between 0° and -90°), that is considered left axis deviation. If the axis is to the right (between +90° and -90°), it is considered right axis deviation. 20. Which of the following skin preparations should be done before Holter monitor electrode placement? a. Abrasion of the skin b. Removal of all chest hair c. Disinfection of the skin d. Moisturization of the skin - correct answers 20. A: Abrading the thin outer layer of skin helps the electrodes adhere better to the skin, making them less likely to lose contact. The electrodes are also taped to the skin. If a patient has an especially hairy chest, the chest hair may need to be clipped in order to allow for proper adherence, but removal of all chest hair is not necessary. Disinfection and moisturization are not typical steps in skin preparation. 21. Where is the sinoatrial node located? a. Medial part of left atrium b. Posterior part of right atrium c. Superior part of left atrium d. Inferior part of right atrium - correct answers 21. B: The SA node is located in the posterior wall of the right atrium, near the entrance of the superior vena cava. The d. effective refractory period. - correct answers 25. D: The effective refractory period (ERP) acts as a protective mechanism for the heart by preventing irregular cellular depolarization. The refractory period limits the frequency of contractions that can be generated by the heart. 26. If a patient's heart rate suddenly drops to 40 beats per minute (bpm) and he becomes acutely confused and ill, what medication should be given first? a. Dopamine b. Sotalol c. Epinephrine d. Atropine - correct answers 26. D: Atropine is the first drug of choice for symptomatic bradycardia. Dopamine and epinephrine are second-line agents for treating symptomatic bradycardia. Sotalol is a beta-blocker that would further slow the heart rate. 27. In which individuals is spontaneous fluctuation in the PR interval most often seen? a. Individuals with normal hearts b. Individuals on beta-blockers c. Individuals with an AV nodal bypass track d. Individuals with an AV block - correct answers 27. A: The PR interval represents speed of conduction from the atria to the ventricles. It may be shortened with increased heart rate, and lengthened with decreased heart rate. The speed of the heart rate is influenced by the sympathetic and parasympathetic nervous systems. This is the most common cause of spontaneous fluctuation in the PR interval. Certain medications and pathologies may also affect the PR interval, but often these changes are more consistent. Beta-blockers typically lengthen the PR interval. Individuals with an AV nodal bypass track typically have a shortened PR interval. An AV block may lengthen the PR interval. 28. In order for an exercise stress test to be adequate, the patient must reach what percentage of his or her age- predicted maximum heart rate? a. 65% b. 75% c. 85% d. 95% - correct answers 28. C: A patient needs to achieve 85% to 90% of his or her age-predicted maximum heart rate during an exercise stress test in order for the test to be considered adequate for the detection of myocardial ischemia. If the patient is unable to exercise at this level, other forms of testing, such as pharmacologic stress testing, may need to be considered. 29. The right and left coronary arteries branch off of which blood vessel? a. Ascending aorta b. Descending aorta c. Pulmonary artery d. Posterior descending artery - correct answers 29. A: The right and left coronary arteries branch off from the root of the ascending aorta. The root of the ascending aorta refers to the beginning of the aorta, immediately after it exits the left ventricle. 30. What type of rhythm is seen in the following ECG strip? a. Normal sinus rhythm b. Sinus tachycardia c. Supraventricular tachycardia d. Atrial flutter - correct answers 30. B: Sinus tachycardia has a normal rhythm, but the rate is over 100 bpm. Normal sinus rhythm is 60 to 100 bpm. The P wave, QRS complex, and T wave are still present in sinus tachycardia, although they may be more difficult to differentiate if the rate is very high. 31. Which of the following would be LEAST likely to complicate the diagnosis of myocardial ischemia based on Holter monitor tracings? a. If the patient has atrial fibrillation b. If the patient has a left bundle branch block c. If the patient is on digoxin d. If the patient is on a beta-blocker - correct answers 31. D: It can be very difficult to accurately diagnose 35. Under what conditions might you expect to see consistent and diffuse low amplitude on an ECG? a. In an obese patient b. In a patient with congestive heart failure c. In a very athletic patient d. In a patient with a recent myocardial infarction - correct answers 35. A: An increased amount of poorly conducting tissue, such as fat, will lead to lower amplitude on the surface ECG. Any significant amount of poorly conducting tissue or fluid between the heart and chest wall may result in decreased amplitude of the ECG. Examples of other conditions that may lead to this finding include a pericardial effusion or emphysema. 36. What is the normal resting potential of most myocardial cells? a. Between 0 and 10 mV b. Between 20 and 45 mV c. Between 80 and 95 mV d. Between 100 and 120 mV - correct answers 36. C: The normal resting membrane potential for the majority of myocardial cells is between 80 and 95 mV. The cell interior is negative relative to the extracellular area. The resting potential is set by the balance between inward sodium and calcium currents and outward potassium currents. 37. Which of the following is the correct sequence for cardiac blood flow? a. Vena cava → left atrium → mitral valve → left ventricle → pulmonary valve→ pulmonary artery → lungs → pulmonary vein → right atrium → tricuspid valve → right ventricle → aortic valve → aorta b. Vena cava → right atrium → mitral valve → right ventricle → pulmonary valve → pulmonary artery → lungs → pulmonary vein → left atrium → tricuspid valve→ left ventricle → aortic valve → aorta c. Vena cava → right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary artery → lungs → pulmonary vein → left atrium → mitral valve→ left ventricle → aortic valve → aorta d. Vena cava → left atrium → mitral valve → left ventricle → aortic valve → right atrium → tricuspid valve → right ventricle → pulmonary valve→ pulmonary artery → lungs - correct answers 37. C: Deoxygenated blood from the body is carried to the right atrium by the vena cava. It is then pumped to the lungs by the right ventricle, where it becomes oxygenated, and then returned to the left atrium. Oxygenated blood moves from the left atrium to the left ventricle and is then pumped to the body through the aorta. 38. What precautions should be taken to avoid electric shock of the patient when performing an ECG? a. Make sure the patient is directly connected to a ground b. Ensure that the chassis is grounded c. Make sure the patient is connected to monitoring equipment that provides a direct connection to ground d. Avoid the use of line isolation transformers - correct answers 38. B: Any electrical equipment should be treated with care in order to ensure the safety of the patient and the staff using the equipment. To avoid electric shock of a patient, there are several steps that must be taken, including ensuring that the chassis is grounded and making sure that the patient is not connected to a ground or to monitoring equipment that provides a direct connection to the ground. Line isolation transformers prevent a circuit from being completed by connection to ground, thereby reducing electrocution hazard. 39. Which of the following would be more likely to indicate a supraventricular tachycardia as opposed to a ventricular tachycardia on a Holter tracing? a. Heart rate of 200 bpm b. QRS complex of greater than 140 msec c. Monomorphic QRS complexes d. Very slight prematurity of the first complex - correct answers 39. A: QRS duration, QRS morphology, tachycardia speed, and tachycardia onset may be helpful in differentiating ventricular from supraventricular tachycardia. The wider the QRS, the more likely it is of ventricular origin, especially if it is greater than 140 msec. With ventricular tachycardia, a monomorphous a. Atrial flutter b. Transient supraventricular tachycardia c. Ventricular fibrillation d. Muscle tremor - correct answers 43. D: Skeletal muscle tremor can show up as an electrical artifact on ECG tracings. It classically looks like irregular, spiky oscillations of the baseline, and may mimic atrial fibrillation or other cardiac abnormalities. It is necessary to find out the cause of the tremor and to find a solution. If the patient is tense, provide reassurance and ask them to relax. If they are cold, ensure the room is warm and provide blankets. If they have Parkinson disease or another cause of tremor, move the limb electrodes closer to the torso or have the patient tuck their hands under their body. 44. Which of the following is appropriate electrode placement with ambulatory ECG monitors? a. Four electrodes are placed on the trunk b. Five electrodes are placed on the trunk, and one electrode is placed on each shoulder c. Five or more electrodes are placed on the trunk d. Six electrodes are placed on the trunk, one electrode is placed on the left upper thigh, and one electrode is placed on each shoulder - correct answers 44. C: Five or more electrodes are placed on the trunk for the purposes of ambulatory monitoring. Electrodes are not placed on the arms and legs because of the high probability of muscle artifact. 45. Which of the following activities should the patient avoid while the Holter monitor is in use? a. Yard work b. Sex c. Showering d. Running - correct answers 45. C: Showering and bathing should be avoided while the Holter monitor is in use, as these activities are likely to cause the electrodes to become dislodged. All other normal daily activities should be continued. The purpose of the Holter monitor is to catch abnormalities that occur during normal daily activities. 46. Which of the following describes what would classically be seen on ECG if a patient has atrial flutter? a. A rapid run of identical, consecutive waves that mask the baseline and are interspersed with QRS complexes b. Continuous chaotic spikes that mask the baseline along with irregularly interspersed QRS complexes c. Normal appearing sequences of P waves and QRS complexes that occur at a much faster rate than normal d. A rapid series of waves of similar amplitude appearing as a smooth, wavy line - correct answers 46. A: "A" describes the classic look of atrial flutter on ECG. This is often described as a "saw-tooth" pattern. Inverting the tracing may help you identify this abnormality. "B" describes what may be seen in a case of atrial fibrillation. "C" describes what is most likely sinus tachycardia. "D" describes ventricular flutter. 47. How are cardiac cells able to depolarize spontaneously and thus demonstrate automaticity? a. They are consistently triggered by the sympathetic nervous system b. They have an unstable resting potential that allows influx of calcium and sodium c. They have increased permeability to potassium ions while in a resting state d. Parasympathetic nervous system fibers regularly trigger the cells - correct answers 47. B: Certain cardiac cells spontaneously depolarize, which is referred to as automaticity. The depolarization of the cell leads to an action potential being formed. Spontaneously depolarizing cardiac cells, such as those in the SA node, have unstable resting potentials created by positive sodium and calcium ions flowing slowly and continuously into the cell while the cell is at rest. As a result of the inflow of positive ions, the cell slowly depolarizes until it reaches a point where it triggers a change in membrane permeability. This change allows for the positively charged ions (mainly sodium) to move more quickly into the cell, depolarizing it further until an action potential is produced. The plasma membranes of these cells have