Ch 27: Heart Failure & Circulatory Shock

The rise in preload seen in systolic dysfunction is believed to be a compensatory mechanism to help maintain stroke volume via the _____ mechanism despite a drop in ejection fraction.

Frank-Starling

transudation of fluid into pleural cavity

hydrothorax

What are the signs and symptoms of heart failure? Mark all that apply. a. Fluid retention b. Ruddy complexion c. Fatigue d. Bradycardia e. Chronic productive cough

a. fluid retention c. fatigue RATIONALE: The signs and symptoms of heart failure include shortness of breath and other respiratory manifestations, fatigue and limited exercise tolerance, fluid retention and edema, cachexia and malnutrition, and cyanosis.

When an acute event occurs and the circulatory system can no longer provide the body with adequate perfusion of its tissues and organs, cellular hypoxia occurs, and the body goes into shock. What are the causes of shock in the human body? Mark all that apply. a. Maldistribution of blood flow b. Hypovolemia c. Excessive vasoconstriction d. Obstruction of blood flow e. Hypervolemia

a. maldistribution of blood flow b. hypovolemia d. obstruction of blood flow RATIONALE: It can be caused by an alteration in cardiac function (cardiogenic shock), a decrease in blood volume (hypovolemic shock), excessive vasodilation with maldistribution of blood flow (distributive shock), or obstruction of blood flow through the circulatory system (obstructive shock).

In acute or severe left-sided failure, cardiac output may fall to levels that are insufficient for providing the _____ with adequate oxygen.

brain

Among the conditions that cause diastolic dysfunction are those that _____ the ventricle, those that _____ wall thickness and reduce chamber size, and those that _____ diastolic relaxation.

compress, increase, delay

right heart failure occurs in response to chronic pulmonary disease

cor pulmonale

bluish discoloration of skin

cyanosis

In systolic ventricular dysfunction, myocardial contractility is impaired, leading to a _____ in the ejection fraction and cardiac output.

decrease

labored breathing

dyspnea

potent vasoconstrictors

endothelin

contractile performance of the heart

inotropy

The most common causes of ____ _ ventricular dysfunction are acute myocardial infarction and cardiomyopathy.

left

_____ is the most common cause of right ventricular failure.

left ventricular failure

Diastolic ventricular dysfunction is characterized by a _____ ejection fraction but impaired diastolic ventricular relaxation, leading to a decrease in ventricular filling that ultimately causes a decrease in preload, stroke volume, and cardiac output.

normal

shortness of breath when supine

orthopnea

_____ dyspnea is a sudden attack of dyspnea that occurs during sleep.

paroxysmal nocturnal

A major effect of right-sided heart failure is the development of ____ .

peripheral edema

volume or loading conditions of ventricle at end of diastole

preload

common sign of left ventricular failure

pulmonary congestion

The _____ is a function of preload, afterload, and myocardial contractility.

stroke volume

ejection fraction less than 40%

systolic dysfunction

force that the contracting heart muscle must generate to eject blood from the filled heart

afterload

_____ is associated with impaired left ventricular filling that is due to changes in myocardial relaxation and compliance.

aging

right ventricular dysfunction

aortic or mitral stenosis

transudation of fluid into peritoneal cavity

ascites

periodic breathing characterized by gradual increase in depth, followed by decrease resulting in apnea

chyene-stokes respiration

Neurogenic shock, or spinal shock, is a phenomenon caused by the inability of the vasomotor center in the brain stem to control blood vessel tone through the sympathetic outflow to the blood vessels. In neurogenic shock, what happens to the heart rate and the skin? a. Heart rate slower than normal; skin warm and dry b. Heart rate faster than normal; skin cool and moist c. Heart rate slower than normal; skin cool and moist d. Heart rate slower than normal; skin warm and dry

a. Heart rate slower than normal; skin warm & dry RATIONALE: In contrast to other shock states due to the loss of blood volume or impaired cardiac function, the heart rate in neurogenic shock is often slower than normal, and the skin is dry and warm.

Sepsis is a growing incidence in the United States. Its pathogenesis includes neutrophil activation that kills microorganisms. Neutrophils also injure the endothelium, releasing mediators that increase vascular permeability. What else do neutrophils do in sepsis? a. Release nitric oxide b. Vasoconstrict the capillary bed c. Cause bradycardia d. Activate erythropoiesis

a. Release nitric oxide RATIONALE: Although activated neutrophils kill microorganisms, they also injure the endothelium by releasing mediators that increase vascular permeability.

What are the physiologic signs and symptoms of cardiogenic shock? Mark all that apply. a. Decreased mean arterial blood pressures b. Increased urine output related to increased renal perfusion c. Increased central venous pressure d. Hypercapnic lips and nail beds e. Increased extraction of O2 from hemoglobin

a. decreased MAP c. increased CVP e. increased extraction of O2 from hemoglobin RATIONALE: Signs and symptoms of cardiogenic shock include indications of hypoperfusion with hypotension, although a preshock state of hypoperfusion may occur with a normal blood pressure.

left ventricular dysfunction

acute myocardial infarction

What is the primary physiologic result of obstructive shock? a. Left ventricular hypertrophy b. Elevated right heart pressure c. Right atrial hypertrophy d. Decreased right heart pressure

b. Elevated right heart pressure RATIONALE: The primary physiologic result of obstructive shock is elevated right heart pressure due to impaired right ventricular function.

Anaphylactic shock is the most severe form of systemic allergic reaction. Immunologically medicated substances are released into the blood, causing vasodilation and an increase in capillary permeability. What physiologic response often accompanies the vascular response in anaphylaxis? a. Uterine smooth muscle relaxation b. Laryngeal edema c. Bronchodilation d. Gastrointestinal relaxation

b. Laryngeal edema RATIONALE: Anaphylaxis is a clinical syndrome that represents the most severe form of systemic allergic reaction. Anaphylactic shock results from an immune-mediated reaction in which vasodilator substances such as histamine are released into the blood.

What is the primary cause of heart failure in infants and children? a. Idiopathic heart disease b. Structural heart defects c. Hyperkalemia d. Reaction to medications

b. Structural heart defects RATIONALE: Structural (congenital) heart defects are the most common cause of heart failure in children.

The pathogenesis of multiorgan dysfunction syndrome (MODS) is not clearly understood at this time. Supportive management is currently the focus of treatment in this disorder. What is not a major risk factor in MODS? a. Advanced age b. Alcohol abuse c. Respiratory dysfunction d. Infarcted bowel

c. Respiratory dysfunction RATIONALE: Major risk factors for the development of MODS are severe trauma, sepsis, prolonged periods of hypotension, hepatic dysfunction, infarcted bowel, advanced age, and alcohol abuse.

An important factor in the mortality of severe shock is acute renal failure. What is the degree of renal damage related to in shock? a. Loss of perfusion and duration of shock b. Loss of perfusion and degree of immunemediated response c. Severity and duration of shock d. Severity of shock and degree of immunemediated response

c. Severity & duration of shock RATIONALE: The degree of renal damage in shock is related to the severity and duration of shock.

In hypovolemic shock, the main purpose of treatment is correcting or controlling the underlying cause of the hypovolemia and improving the perfusion of the tissues and organs of the body. Which of the following treatments is not a primary form of therapy for hypovolemic shock? a. Surgery b. Administration of IV fluids and blood c. Vasoconstrictive drugs d. Infusion of blood and blood products

c. vasoconstrictive drugs RATIONALE: The treatment of hypovolemic shock is directed toward correcting or controlling the underlying cause and improving tissue perfusion. Ongoing loss of blood must be corrected, such as in surgery.

bronchospasm due to congestion of bronchial mucosa

cardiac asthma

amount of blood the ventricles eject each minute

cardiac output

ability to increase cardiac output during increased activity

cardiac reserve

low-output failure

cardiomyopathy

hypoperfusion of organs and tissues

circulatory failure

As venous distention progresses in rightsided heart failure, blood backs up in the _____ veins that drain into the inferior vena cava, and the liver becomes engorged.

hepatic

failure caused by excessive need for cardiac output

high-output failure