Which of the following factors can directly affect cardiac output?
Respiratory rate
Stroke volume
Heart rate
Blood pressure
Correct Answer : B,C
B. stroke volume is the amount of blood ejected from the left ventricle with each contraction (systole) of the heart. Changes in stroke volume directly affect cardiac output. An increase in stroke volume leads to an increase in cardiac output, while a decrease in stroke volume results in a decrease in cardiac output. Factors that can affect stroke volume include preload, afterload, and contractility of the heart.
C. Heart rate refers to the number of heartbeats per minute. Heart rate directly affects cardiac output by determining how frequently the heart contracts and pumps blood. An increase in heart rate (tachycardia) leads to an increase in cardiac output, while a decrease in heart rate (bradycardia) results in a decrease in cardiac output. Factors such as sympathetic and parasympathetic nervous system activity, hormones, and medications can influence heart rate.
A. Respiratory rate does not directly affect stroke volume or heart rate but changes in respiratory rate can indirectly impact cardiac output through their effects on venous return and preload.
D. Blood pressure represents the force exerted by the blood against the walls of the arteries. While blood pressure does not directly affect cardiac output, it is influenced by cardiac output and systemic vascular resistance (SVR).
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
A The first intervention should be to ensure adequate oxygenation, as hypoxia can exacerbate shock. Therefore, providing oxygen at 100% via a non-rebreather mask is the most critical initial step. This intervention helps to maximize the amount of oxygen delivered to the patient's lungs and subsequently to the rest of the body, supporting vital organ function while further assessments and interventions are prepared.
B Continuous ECG monitoring allows for the assessment of the patient's heart rhythm, rate, and any signs of dysrhythmias or cardiac ischemia. This intervention is important for detecting any life- threatening arrhythmias, such as ventricular tachycardia or fibrillation, which may require immediate intervention. While ECG monitoring is important, it may not be the highest priority intervention.
C Drawing blood for type and crossmatch is important for preparing for potential blood transfusions if significant blood loss is suspected. However, this intervention may take some time to process, and immediate stabilization of the patient's condition is paramount.
D Large-bore IV catheters allow for rapid infusion of fluids to restore intravascular volume and improve tissue perfusion. This intervention is critical for stabilizing the patient's hemodynamic status and takes precedence in the management of shock. However, oxygenation should take priority.
Correct Answer is D
Explanation
D. Myocardial infarction (heart attack) is a common cause of cardiogenic shock. In myocardial infarction, part of the heart muscle becomes ischemic or necrotic due to occlusion of a coronary artery. This leads to impaired cardiac function and reduced cardiac output, resulting in cardiogenic shock. Prompt recognition and treatment of myocardial infarction are crucial to prevent or manage cardiogenic shock.
A. Anaphylaxis is a severe allergic reaction that can lead to systemic vasodilation and distributive shock, but it is not a common cause of cardiogenic shock. In anaphylaxis, the primary mechanism of shock is typically related to widespread vasodilation and increased vascular permeability rather than impaired cardiac function.
B. Hypovolemic shock occurs due to a decrease in intravascular volume, leading to inadequate tissue perfusion. It is not a common cause of cardiogenic shock, as the underlying mechanism is different. In hypovolemic shock, the primary issue is the loss of circulating blood volume, whereas cardiogenic shock involves impaired cardiac function.
C. Pulmonary embolism can lead to acute right heart strain or failure, which may result in hemodynamic instability and shock. However, pulmonary embolism typically causes obstructive shock rather than cardiogenic shock. Obstructive shock occurs when blood flow is obstructed, such as by a pulmonary embolism, leading to reduced cardiac output.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.
