This document provides an overview of chronic heart failure for nursing students. It defines heart failure as the heart's inability to pump enough blood to meet the body's needs. It explains the pathophysiology of heart failure including compensatory mechanisms and the differences between left and right sided heart failure. The document discusses medical treatments to reduce workload on the heart including diuretics, ACE inhibitors, and beta blockers. Nursing diagnoses and interventions for patients with heart failure are also reviewed.
2. Student Resources Brunner, L. S., Suddarth, D. S., & Smeltzer, S. C. (2008). Brunner & Suddarth's textbook of medical-surgical nursing (11th ed.). Philadelphia: Lippincott Williams & Wilkins. Chapter 26: Assessment of Cardiovascular Function Chapter 30: Management of Patients with Complications from Heart Disease
3. Objectives Explain normal and abnormal pathophysiology of the heart in relation to chronic heart failure. Differentiate between left and right sided heart failure. Discuss current medical treatments for patients with heart failure. Discuss common teaching principles related to heart failure. Utilize the nursing process as a framework for care in patients with heart failure. Demonstrate competent and compassionate nursing care for the heart failure patient.
4. Stroke Volume The amount of blood pumped by the ventricles per beat. Average resting SV is 60-80 ml (2 Ounces) per beat.
5. Cardiac Output CO – the amount of blood pumped by the heart in 1 minute. Normal CO = 5 Liters per min CO = Heart rate X stroke volume The entire blood volume passes through the heart every minute
6. Starling’s Law of the Heart The greater the stretch of the myocardial fibers, the stronger the force of the contraction.
7. Inotropic effect Positive inotropic effect – increase stroke volume by increasing the force of contraction without stretching the fibers. Digitalis Negative Inotropic Effect – decrease in contraction
8. Congestive Heart Failure Heart is unable to pump adequate amount of blood to meet metabolic needs CHF describes the accumulation of blood and fluid in organs and tissues from impaired circulation.
11. Preload The amount of blood presented to the ventricles just before systole. Blood volume - stretches cardiac muscle fibers Ventricular compliance – the elasticity or amount of give when blood enters ventricle. Ventricular hypertrophy = decreased ventricular compliance
12. Afterload The amount of resistance to the ejection of blood from the ventricle. Resistance caused by tension in aorta and systemic vessels.
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14. Contractility The force of contraction Catecholamines – released by SNS, increases contractility and stroke volume MI = myocardial cell damage = decreased contractility = HF
15. Test Your Knowledge Stroke Volume of the heart is determined by: The degree of cardiac muscle strength. The intrinsic contractility of the cardiac muscle. The pressure gradient against which the muscle ejects blood during contraction. All of the above
16. Heart Failure The inability of the heart to pump sufficient blood to meet the needs of the tissues for oxygen and nutrients
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18. Compensatory Mechanisms: Ventricular dilation Muscle fibers stretch.. Increase contractile force Increases cardiac output / blood pressure Eventually inadequate …overstretched/overstrained Ventricular hypertrophy Increase in muscle mass Hypertrophic muscle has POOR contractility Increased SNS stimulation First mechanism triggered LEAST EFFECTIVE mechanism Increased workload causes increased demand for O2
25. Chronic Heart Failure Types of CHF: Usually manifested by biventricular failure One ventricle may precede the other Prolonged strain …. causes remaining side to fail
26. Left-Sided Heart Failure Results from LV dysfunction Blood backs up into LEFT atrium Pulmonary congestion and edema
34. Right-Sided Failure What is #1 Cause? Results from diseased right ventricle Blood backs up into right atrium and venous circulation S & S:
35. S & S Right Sided Failure Peripheral edema Hepatomegaly Splenomegaly Vascular congestion in GI tract Jugular venous distention ABD distention (ascites) from portal hypertension
38. Test Your Knowledge When collecting subjective data, the nurse could expect that the client who is developing left-sided congestive heart failure would describe having: a. to sleep in a reclining chair b. intolerance for fatty foods c. tight fitting shoes d. to urinate frequently
39. Test Your Knowledge All of the following are clinical manifestations of right-sided heart failure except: Hepatomegaly Jugular vein distention Ascites Orthopnea
40. Ejection Fraction The percentage of blood the LV ejects when it contracts Normal = 55% - 65% Mild reduction= 45-55% Moderately reduced = 35-45% Severely reduced = < 35%
41. BNP Brain (B-Type) Natriuretic Peptide Helps regulate BP and fluid volume Secreted from the ventricles in response to increased preload Used to diagnose and monitor HF > 51.2 pg/mL = mild HF > 1000 pg/mL = severe HF
42. Managementof CHF and Pulmonary Edema Reduce the heart’s workload Improve cardiac output How do we do that?
43. Drug Therapy for Chronic HF Goals: Identification of TYPE of HF and underlying cause Correction of Na+ and water retention Reduction of cardiac workload Improvement of cardiac contractility
44. Drug Categories for Treating CHF Drug Categories for Treating HF Standard TX: Diuretics ACE inhibitors Beta Blockers Other drugs used: Cardiac Glycosides (Positive inotropic drugs)[Digoxin] Vasodilator drugs[Nitroprusside] Nonglycoside inotropic Agents (Dobutrex) See Brunner pgs 952-956
46. Test Your Knowledge A client admitted with heart failure who is taking a thiazide diuretic has been ordered to receive furosemide (Lasix). What side effect of these medications should the nurse be alert for? a. Hypertension b. Headache c. Bradycardia d. Arrhythmias
47. Test Your Knowledge The treatment of cardiac failure is directed at: Decreasing oxygen needs of the heart Increasing CO by strengthening muscle contraction and decreasing PVR Reducing the amount of circulating blood volume All of the above
48. Test Your Knowledge The physiologic effect of an angiotensin converting enzyme inhibitor in the management of congestive heart failure includes which of the following: (Mark all that apply) a. Decrease peripheral vascular resistance (PVR) b. Decrease in heart rate c. Increase myocardial contractility d. Decrease in afterload
51. Test Your Knowledge If a client with left sided heart failure experiences paroxysmal nocturnal dyspnea, which one of the following would be most appropriate to add to the plan of care? a. Place the client on an alternating pressure mattress b. Use several pillows to support the head and thorax c. Administer oxygen per nasal cannula at bedtime d. Cough forcefully to expectorate accumulated secretions
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53. Resources Lehne, R.A., Pharmacology For Nursing Care, 7th Edition, 2010, Elsevier Brunner, L. S., Suddarth, D. S., & Smeltzer, S. C. (2008). Brunner & Suddarth's textbook of medical-surgical nursing (11th ed.). Philadelphia: Lippincott Williams & Wilkins.
Notes de l'éditeur
Heart FailureAround 5 million people in the United States have heart failure. About 550 thousand new cases are diagnosed each year. More than 287 thousand people in the United States die each year with heart failure.1 Hospitalizations for heart failure have increased substantially. They rose from 402,000 in 1979 to 1,101,000 in 2004.(National Hospital Discharge Survey) Heart failure is the most common reason for hospitalization among people on Medicare. Hospitalizations for heart failure are higher in black than white people on Medicare.2,3 The most common causes of heart failure are coronary artery disease, hypertension or high blood pressure, and diabetes. About 7 of 10 people with heart failure had high blood pressure before being diagnosed. About 22 percent of men and 46 percent of women will develop heart failure within 6 years of having a heart attack.1,4 Heart failure as an underlying or contributing cause of death—286,700 (2003)1 From 1993–2003, deaths from heart failure (ICD–9 428) increased 20.5%. In the same time period, the death rate declined 2%. The 2003 overall death rate for heart failure was 19.7 per 100,000. Death rates were 20.5 for white males, 23.4 for black males, 18.4 for white females and 20.4 for black females.1
Increase pressure = increased stretch of ventricular wall.Ventricular muscle fibers are stretched by blood volume.Major factor that affects preload is venous return.Ventricular compliance – the elasticity or amount of give when blood enters ventricle.Ventricular hypertrophy = decreased ventricular compliance
Discuss the diameter and distensibility of the great vessels and effect on PVR and afterload.Discuss the diameter of the semilunar valves and effect of PVR and afterload.
Answer D : all of the above
Heart Failure:The inability of the heart to pump sufficient blood to meet the needs of the tissues for oxygen and nutrientsA syndrome characterized by fluid overload or inadequate tissue perfusionThe term HF indicates myocardial disease, in which there is a problem with the contraction of the heart (systolic failure) or filling of the heart (diastolic failure).Some cases are reversible.Most HF is a progressive, lifelong disorder managed with lifestyle changes and medications.
Discuss pathophysiology of HFFollow chart discussing:Causes of HFPathophysiology (resulting low C/O, decreased B/P, decreased renal perfusion)Baroreceptors activation = activation of SNSActivation of Renin-angiotensin-aldosterone system = sodium and water retention, vasoconstriction = increased afterload, increased B/P, increased HR = Remodeling and LVHRemodeling and ventricular hypertrophy = impaired filling and contractility
Open space inside the ventricles can be restricted by heart muscle that “bulks up” due to overwork or other causes or that stiffens and loses it flexibility.Diastolic Failure When your heart is thick and stiff, you have diastolic failure. Your EF may be normal (over 40%), but your heart resists filling with blood because it cannot relax. Pumping against high blood pressure is the most common cause of this type of heart failure. Diastolic failureNormal ejection fractionBlood backs up in systemic systemsOpen space inside the ventricles can be restricted by heart muscle that “bulks up” due to overwork or other causes or that stiffens and loses it flexibility.The heart’s ventricles can have trouble filling with blood for two main reasons. Overworked heart muscle can “bulk up,” like a weightlifter; this reduces the open space inside the ventricles. Alternatively, the heart muscle may stiffen and become less flexible.Bulking and stiffening are sometimes the result of genetic signals. Most of the time, though, they have more immediate causes. High blood pressure is one of the most common causes of diastolic trouble. Diabetes, cholesterol-clogged arteries, and narrowed heart valves also contribute to the problem. Less common causes include conditions that cause protein, iron, and other substances to infiltrate heart muscle. Such conditions include amyloidosis, hemochromatosis, and sarcoidosis.
