Correct Answer: A

Rationale: An INR of 3.8 is elevated, indicating an increased risk of bleeding. Administering vitamin K can help reverse the effects of warfarin. Holding the next dose of warfarin would be appropriate if the INR was too high, but not as the first-line action. Increasing the dose of warfarin would worsen the situation by further increasing the INR. Notifying the healthcare provider is important, but immediate action to address the elevated INR is necessary.

Correct Answer: A

Rationale: The correct answer is A: Ejection fraction. Ejection fraction is a measure of the percentage of blood that is pumped out of the left ventricle with each beat, used to assess heart function. Choice B, Cardiac output, is the total volume of blood pumped by the heart per minute and is not specific to each beat. Choice C, Stroke volume, is the amount of blood ejected by the heart in one contraction but does not specify the percentage of blood pumped out. Choice D, End-diastolic volume, is the volume of blood in the ventricle just before it contracts and does not directly measure the blood pumped with each beat.

Correct Answer: A

Rationale: The correct answer is A: Cardiogenic shock. Cardiogenic shock is a severe condition characterized by the heart's inability to pump enough blood, leading to decreased cardiac output and tissue perfusion, which can result in organ failure. Choice B, Myocardial infarction, specifically refers to a blockage of blood flow to the heart muscle. Choices C and D, Endocarditis and Pericarditis, do not directly involve decreased cardiac output leading to organ failure, making them incorrect in the context of the symptoms described in the question.

Correct Answer: B

Rationale: The correct answer is B: Pulmonary valve. The pulmonary valve opens during ventricular systole to allow blood to flow from the right ventricle into the pulmonary artery. The aortic valve opens during ventricular systole to allow blood to flow from the left ventricle into the aorta. The mitral valve and tricuspid valve are atrioventricular valves that open during ventricular diastole to allow blood to flow from the atria into the ventricles.

Correct Answer: A

Rationale: Asthma is the correct answer. It is a condition characterized by inflammation, narrowing, and swelling of the airways, leading to symptoms like wheezing, shortness of breath, and coughing. Bronchitis is the inflammation of the bronchial tubes; Pleurisy is inflammation of the tissues that line the lungs and chest cavity; Tuberculosis is a bacterial infection that mainly affects the lungs.