Chapter 20

A PCWP of 25 mm Hg and a CI of 1.5 L/min/m2 is consistent with which of the following conditions? a. Left ventricular failure b. Blood volume loss c. Pulmonary edema d. Peripheral hypoperfusion

A A PCWP of 25 mm Hg and a CI of 1.5 L/min/m2 is consistent with left ventricular pumping failure.

What is considered the hallmark of cardiac contractility? a. Preload pressure b. Afterload pressure c. Mean arterial blood pressure d. Conduction rate

A Cardiac output and venous return are greater at a lower right atrial (preload) pressure, which is the hallmark of increased contractility.

Which of the following is considered a preload pressure? a. LVEDP b. CVP c. PCWP d. MAP

A In clinical practice, measurement of right atrial and left atrial pressures is used to estimate the preload. These pressures represent the right and left ventricular "loading," or "filling" pressures and are equivalent to right ventricular end-diastolic pressure (RVEDP) and left ventricular end-diastolic pressure (LVEDP).

Stroke volume is determined by which of the following factors? I. Preload II. Afterload III. Contractility IV. Conduction rate a. I, II, III b. III, IV c. I, II, III, IV d. II, III

A Stroke volume is determined by three factors: (1) preload, (2) afterload, and (3) contractility

A PCWP of 5 mm Hg and a CI of 1.5 L/min/m2 is consistent with which of the following conditions? a. Left ventricular failure b. Blood volume loss c. Pulmonary edema d. Peripheral hypoperfusion

B A PCWP of 5 mm Hg and a CI of 1.5 L/min/m2 is consistent with a loss of blood volume, as with hemorrhage.

Which of the following pressures is an indicator of afterload? a. RAP b. MPAP c. PCWP d. CVP

B Mean pulmonary artery pressure (MPAP) and systemic artery pressure are indicators of right and left ventricular afterloads.

Which of the following mechanisms are responsible for compensating heart failure? I. Improved contractility II. Vasoconstriction III. Fluid retention IV. Vasodilation a. I, II, IV b. I, II, III c. III, IV d. II, III, IV

B The combination of (1) improved contractility, (2) vasoconstriction, and (3) renal fluid retention creates a new compensated equilibrium point. This is known as compensated heart failure.

Which of the following are the main clinical reasons for measuring PCWP? I. To measure pulmonary capillary hydrostatic pressure II. To estimate cardiac output III. To estimate the filling pressure of the left ventricle IV. To estimate the filling pressure of the right ventricle a. I, II, III b. I, III c. II, III, IV d. I, II, III, IV

B The two main clinical reasons for measuring pulmonary capillary wedge pressure (PCWP) are to (1) measure pulmonary capillary hydrostatic pressure and (2) estimate the filling pressure of the left ventricle.

Which pharmacologic agent should be administered to a patient with abnormally low vascular resistance? a. Inotropes b. IV fluids c. Vasopressors d. Oxygen

C Abnormally low SVR and SVRI are caused by excessive vasodilation. The resulting fall in blood pressure leads to underperfused and underoxygenated tissues. This may decrease coronary perfusion and cause myocardial ischemia, reducing the cardiac output. In this case, vasopressor drugs are needed to induce vasoconstriction.

How soon after coronary artery occlusion should fibrinolytics be administered to improve survival? a. Within 5 minutes b. Within 1 hour c. Within 2 hours d. Within 24 hours

C Drugs that dissolve blood clots (fibrinolytic therapy) improve the survival of patients suffering acute coronary artery occlusion, especially if the drug is given within 2 hours of the occlusion.

Which of the following are signs and symptoms of left ventricular failure? I. High systemic blood pressure II. Dyspnea III. Skin cool and clammy IV. Fine crackles a. I, II, IV b. I, II, III c. II, III, IV d. I, II, III, IV

C The physical examination of a patient with acute left ventricular failure may reveal some or all of the following signs and symptoms: • The patient complains of dyspnea. • Fine crackles (breath sounds) are heard on auscultation. • Symptoms worsen when the patient lies flat (known as orthopnea). • Systemic blood pressure is low. • Skin is cool and clammy. • Neck veins (jugular veins) are pulsating and distended even in the sitting position. • Palpation reveals an enlarged liver (hepatomegaly). • Ankles and lower legs are swollen (pedal edema).

Which of the following is still considered the gold standard method of measuring hemodynamic variables such as cardiac output? a. Peripheral arterial catheter b. Central venous line c. Swan-Ganz catheter d. Femoral vein catheter

C The pulmonary artery catheter, often referred to the Swan-Ganz catheter, is an essential tool in measuring hemodynamic variables.

Where is the Swan-Ganz catheter placed if a waveform shows a clear, sharp upstroke on the left, falling to a distinct notch in the downstroke on the right? a. Left atrium b. Right ventricle c. Pulmonary artery d. Right atrium

C The pulmonary artery waveform, shown in Figure 20-15, has a clear, sharp upstroke on the left, falling to a distinct notch in the downstroke on the right.

When the balloon-tipped catheter wedges in a small pulmonary arteriole, the blood pressure measured through the distal lumen is approximately the same as which of the following? a. Right atrium b. Right ventricle c. Left atrium d. Left ventricle

C When the balloon-tipped catheter wedges in a small pulmonary arteriole, it blocks blood flow between the catheter's distal lumen and the left atrium. Because blood flow is stopped, the blood pressure measured through the distal lumen is approximately the same as the left atrial pressure.

Which of the following measurements is associated with increased afterload and with increased myocardial work and oxygen consumption for a given cardiac output? a. LVEDP b. CVP c. PCWP d. MAP

D A clinical indicator of left ventricular afterload is the mean arterial pressure (MAP). As one might predict, an increase in afterload increases myocardial work and oxygen consumption for a given cardiac output.

What is a major concern in the administration of inotropic drugs for myocardial infarction? a. They produce vasodilation. b. They increase heart rate. c. They produce reactive vasoconstriction. d. They increase myocardial work and oxygen demand.

D A major concern in administration of inotropic drugs is that these agents may worsen myocardial ischemia by increasing myocardial work and oxygen demand.

Which of the following pressures is a clinical indicator of ventricular afterload? a. LVEDP b. CVP c. PCWP d. MAP

D Clinical indicators of left and right ventricular afterload are the mean aortic pressure (MAP) and the mean pulmonary artery pressure (MPAP), respectively

Which of the following statements are true of ejection fraction? I. It is a measure of ventricular contractility. II. The heart's normal ejection fraction is approximately 60% of the end-diastolic volume under resting conditions. III. The heart's normal ejection fraction is approximately 90% of the end-diastolic volume in strenuous exercise. IV. The heart's normal ejection fraction is approximately 80% of the end-diastolic volume under resting conditions. a. I, II b. I, III, IV c. I, II, III, IV d. I, II, III

D Ejection fraction is a measure of ventricular contractility. The heart's normal ejection fraction is approximately 60% of the end-diastolic volume under resting conditions; in strenuous exercise it may increase to 90%.

Increased sympathetic activity is associated with which of the following cardiac events? I. Increased cardiac output II. Low RAP III. Increased venous return IV. Increased cardiac contractility a. I, II, IV b. II, III c. I, III, IV d. I, II, III, IV

D Increased sympathetic nervous activity produces an increase in cardiac contractility and increases the cardiac output. This lowers RAP, increasing the venous return pressure gradient.

Which of the following statements are true of PCWP? I. Normally its force is 6 to 12 mm Hg. II. When the PCWP rises above 18 mm Hg, early clinical signs of pulmonary edema appear on the chest x-ray image. III. Above 25 mm Hg the chest x-ray film shows obvious evidence of pulmonary edema. IV. PCWP is a valuable clinical tool for monitoring the effects of intravenous fluid infusions in hemodynamically unstable patients. a. I, II, III b. I, III c. II, III, IV d. I, II, III, IV

D PCWP is the pressure in the pulmonary capillaries tending to force fluid into the interstitial space. Normally, this force of 6 to 12 mm Hg is opposed by capillary osmotic forces, and pulmonary edema is prevented. When the PCWP rises above 18 mm Hg, early clinical signs of pulmonary edema appear on the chest x-ray image. Above 25 mm Hg the chest x-ray film shows obvious evidence of pulmonary edema. Thus, the PCWP is a valuable clinical tool for monitoring the effects of intravenous fluid infusions in hemodynamically unstable patients.

A PCWP > 18 mm Hg and a CI < 2.2 L/min/m2 is consistent with which of the following conditions? a. Left ventricular failure b. Blood volume loss c. Pulmonary edema d. Peripheral hypoperfusion

D The PCWP is a clinical indicator of left ventricular function. People with PCWPs greater than 18 mm Hg had clinical signs of pulmonary edema, and people with cardiac indices (CIs) less than 2.2 L/min/m2 had clinical signs of peripheral hypoperfusion.

Which of the following parameters is the most important in controlling cardiac output in healthy people? a. Pumping ability b. Heart rate c. Conduction rate d. Venous return

D The factors affecting venous return are normally the most important in controlling cardiac output in healthy people.

Which of the following are the major vascular factors that determine venous return and cardiac output? I. Right atrial pressure II. Mean filling pressure of the systemic circulation III. Vascular resistance to blood flow between the peripheral vessels and the right atrium IV. Capillary pressure a. I, II b. III, IV c. I, II, III, IV d. I, II, III

D The major vascular factors that determine venous return and cardiac output are (1) right atrial pressure (RAP), which impedes venous blood return to the heart; (2) mean filling pressure of the systemic circulation, which pushes blood back to the heart; and (3) vascular resistance to blood flow between the peripheral vessels and the right atrium.

Which of the following factors restrict ventricular expansion during diastole? I. An already overstretched, distended ventricle II. Pericardial tamponade III. Myocardial infarction IV. The increased pressure surrounding the heart during positive pressure mechanical ventilation, especially in the presence of high levels of PEEP a. I, II, III b. I, III c. II, III, IV d. I, II, III, IV

D. Factors that restrict ventricular expansion during diastole include (1) an already overstretched, distended ventricle; (2) pericardial tamponade; (3) myocardial infarction; and (4) the increased pressure surrounding the heart during positive pressure mechanical ventilation, especially in the presence of high levels of positive end-expiratory pressure (PEEP).