Book questions Patho Chpt 17

The nurse is caring for a pt who requires bedrest. What percentage of the blood volume will be distributed to the central circulation a) 20% b) 15% c) 10% d) 25%

Body position also affects the distribution of blood volume. in the recumbent position, ~ 25% to 30% of the total blood volume is in the central circulation. on standing, this blood is rapidly displace to the lower part of the body because of the forces of gravity.

Stimulation of the vagus nerve would result in which of the following? a) increase heart rate b)decrease in blood pressure c) Decrease in heart rate d) Increase cardiac contractility

C Increase vagal activity produces a decreases in heart rate

Which of the following blood flow patterns reduces friction, allowing the blood layers to slide smoothly over one another? a) Turbulent b) Axial c) Laminar d) Crosswise

C Ideally, blood flow should be laminar, with the blood components arranged in layers so that the plasma is adjacent to the smooth endothelial surface of the blood vessel that reduces friction. All the other options would result in increased friction

Sympathetic nervous stimulation to the heart will: a) Increase heart rate but decrease contractility. b) decrease both the rate and force of contraction c) increase heart rate and contractility. d) increase contractility and decrease heart rate

C The sympathetic nervous system has an excitatory influence on heart rate and contractility, an serves as the final common pathway for controlling the smooth muscle tone of the blood vessels

Which of the following is the correct sequence for blood return to the heart. a) capillaries -- venules -- veins -- right atrium b) capillaries -- arterioles -- veins -- left atrium c) capillaries -- arterioles -- arteries -- right atrium d) left atrium -- arteries --arterioles -- capillaries

A

A nurse taking a pt. pulse rate is aware that the pulsation felt is related to the a) Pressure pulses b) Blood flow in the veins c) Turbulence of the blood flow d) Korotkoff sounds

A The arterial pressure pulse represents the energy that is transmitted from molecule to molecule along the length of the vessel, and has no direct relation to the blood flow. Pressure pulses would be felt even in the absence of blood flow.

Which of the following heart valves controls the flow of blood between the left atrium and left ventricle. a) Bicuspid valve b) Pulmonic valve c) Aortic valve d) tricuspid valve

A The bicuspid valve, also called the mitral valve, controls the flow of blood between the left atrium and left ventricle. The Tricuspid valve controls the flow between the right atrium and right ventricle. The pulmonic valve controls flow between the right ventricle and pulmonary artery, whearas teh aortic valve controls flow

Which of the following vessel layers is made primarily of muscle? a) Tunica media b) Tunica externa c) Tunica adventitia d) Tunica intima

A The outermost layer of vessel is called the tunica externa or tunica adventitia. The middle layer is largely a smooth muscle layer that constricts to regulate and control the diameter of the vessel. The innermost layer is the tunica intima.

Which of the following helps the nurse assess the pressure being exerted on the right side of the heart? a) CO b) central venous pressure (CVP) c) Blood Pressure d) Pulse pressure

B Blood from the systemic veins flows into the right atrium of the heart; therefore, the pressure in the right atrium is called the central venous pressure. Blood pressure is composed of the systolic blood pressure and the diastolic pressure. The pulse pressure is the diff between systolic and diastolic pressure.

When a pt. experiences the Cushing reflex, what occurs with the body? a) The systemic blood pressure decreases to restore equal amounts of oxygen throughout the body. b) An increase in arterial pressure above the intracranial pressure c) the pupils contract in response to light exposure. d) the toes fan outward in response to stimulation being applied to the bottom of the foot

B This reflex produces a rise in arterial pressure to levels above intracranial pressure so that the blood flow to the vasomotor center can be reestablished. Pupil contraction (papillary response) and the toe fanning (positive Babinski) do not relate with the cushing reflex; neither does the oxygen supply to the body

Which of the following enzymes has a powerful vasodilator effect on arterioles and increased capillary permeability? a) Arachindonic acid b) Prostaglandis c) Serotonin d) Histamine

D Histamine has a powerful vasodilator effect on arterioles and has the ability to increase capillary permeability, allowing leakage of both fluid and plasma proteins into the tissues. Serotonin causes vasoconstriction and plays a major role in control of bleeding. Prostaglandis produce either Vasocon or vasodilation

Which of the following factors increases the heart's output and is dependent on the actions of the heart and the vasculature prior to cardiac contraction? a) Afterload b) Cardiac contractility c) Heart rate d) Preload

D Preload is the distending force that stretches the heart muscle just prior to the work of the onset of ventricular contraction. It represents the volume of blood stretching the ventricular muscle fibers at the end of diastole (i.e., end-diastolic volume) and is the sum of the blood remaining in the heart at the end of systole (end-systolic volume) and the venous return to the heart.

Which of the following best describes the arteral circulation a) It contains approximately two thirds of the total blood volume b) Vessel compliance is greater than compliance in arteries c) The vascular pressure is lower than the venous circulaiton d) it contains one sixth of the total blood volume.

D The arterial side of the circulation, which contains only approximately one sixth of the blood volume, exerts much grewater pressure than the pressue on the venous side of the circulation, which contains approximately two thirds of the blood. The compliance of the vein is approximately 24 times that of its corresponding artery, because it is 8 times as distensible and has a volume 3 times as great.

Which of the following clinical situations might lead to an increase in resistance to blood flow? a) The patient admitted to the intensive care unit for extreme dehydration b) The pt who is receiving intravenous fluid at a rate of 100 ml/hour c) the pt who is hypotensive d) the pt who is being treated for anaphylactic shock

The blood vessels and the blood itself constitute resistance to flow. Viscosity generates resistance to flow by producing friction between the molecule of a liquid. The viscosity of a liquid related to its thickness or the number particles that it contains. the blood of the pt who is extremely dehydrated will be more viscous and thus have increased resistance to flow. the other choices will decrease resistance.

Of the following organs, which has larger capillary pores to allow easier exchange of gases, nutrients, and/or waste products. a) b) c) d)

The liver capillaries have large pores so that substances can pass easily through the capillary wall, whereas the kidney has glomerular capillaries with fenestrations that assist with filtration. Brain and bone have no involvement with the exchange of waste products.