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Learn about the causes, effects, and treatments for congestive heart failure (CHF) and pulmonary edema. Understand the pathophysiology behind CHF and how it leads to fluid accumulation in the lungs. Discover the various etiologies and risk factors for CHF, including coronary artery disease, hypertension, valvular heart disease, dysrhythmias, myocardial infarction, and diabetes. Recognize the symptoms and signs of CHF, such as orthopnea, dyspnea, cyanosis, and pulmonary congestion.
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Congestive Heart Failure and Pulmonary Edema By: Darryl Jamison Macon County EMS Training Coordinator
Approximately 30-40% of patients with CHF are hospitalized each year. Leading diagnosis-related group over 65. The 5 year mortality after Dx was reported as 60% in men and 45% in women in 1971. In 1991, data from the Farmington heart study showed the 5 year mortality rate remaining unchanged, with a median survival of 3.2 years for men, and 5.4 years for women, post dx. The most common cause of death is progressive heart failure, but sudden death may account for up to 45% of all deaths. Patients with coexisting IDDM have a significantly higher mortality rate. Mortality/Morbidity
Effects an estimated 4.9 million Americans 1% of adults 50-60 10% adults over 80 Over 550,000 new cases annually $28.7 million committed in research dollars each year $132 million for lung cancer, affecting 390,000 Americans Responsible for 5-10% of all hospital admissions Causes or contributes to approximately 250,000 deaths per year Background
CHF Defined • An imbalance in pump function in which the heart fails to maintain the circulation of blood adequately.
Pathophysiology • Summarized as an imbalance in Starlings forces or an imbalance in the degree of end-diastolic fiber stretch proportional to the systolic mechanical work expended in the ensuing contraction. • Or basically like a rubber band, the more it is stretched, the greater the releasing velocity.
Under normal circumstances, when fluid is transferred into the lung interstitium with increased lymphatic flow, no increase in interstitial volume occurs. • However, when the capacity of the lymphatic drainage is exceeded, liquid accumulates in the interstitial spaces surrounding the bronchioles and lung vasculature, this creating CHF. • When increased fluid and pressure cause tracking into the interstitial space around the alveoli and disruption of alveolar membrane junctions, fluid floods the alveoli and leads to pulmonary edema
Coronary artery disease--chronic HTN--both Valvular heart disease (especially aorta and mitral disease)--chronic Infections--acute Dysrhythmias--acute Alcohol--chronic MI--acute Diabetes—chronic Etiologies
Preload— The amount of blood the heart must pump with each beat Determined by: Venous return to heart Accompanying stretch of the muscle fibers Increasing preload increase stroke volume in normal heart Increasing preload impaired heart decreased SV. Blood is trapped chamber enlargement Afterload— The pressure that must be overcome for the heart to pump blood into the arterial system. Dependent on the systemic vascular resistance With increased afterload, the heart muscles must work harder to overcome the constricted vascular bed chamber enlargement Increasing the afterload will eventually decrease the cardiac output. Important Terminology
CAD • When cholesterol and fatty deposits build up in the heart’s arteries, less blood reaches the heart muscle. This damages the muscle, and the healthy heart tissue that remains has to work harder
Hypertension • Uncontrolled HTN doubles the chances of failure • With HTN, the chambers of the heart enlarge and weaken.
Valvular Heart Disease • Can result from disease, infection, or be congenital • Don’t open and/or close completely increased workload failure
Disrhythmias • Tachycardias decreased diastolic filling time decreased SV. • Atrial dysrhythmias as much as 30% reduction in stroke volume
MI--Acute and Past • The ischemic tissue is basically taken out of the equation, leaving a portion of the heart to do the work of the entire heart decreased SV CHF.
Diabetes • Tend to be overweight • HTN • Hyperlipidemia
Types of CHF • Left Ventricular Failure with Pulmonary Edema • Aka—systolic heart failure • Right Ventricular Failure • Aka—diastolic heart failure
The smooth, glistening pleural surface of a lung is shown here. This patient had marked pulmonary edema, which increased the fluid in the lymphatics that run between lung lobules. Thus, the lung lobules are outlined in white.
Occurs when the left ventricle fails as an effective forward pump back pressure of blood into the pulmonary circulation pulmonary edema Cannot eject all of the blood delivered from the right heart. Left atrial pressure rises increased pressure in the pulmonary veins and capillaries When pressure becomes to high, the fluid portion of the blood is forced into the alveoli. decreased oxygenation capacity of the lungs AMI common with LVF, suspect Left Ventricular Failure with PE
Severe resp. distress– Evidenced by orthopnea, dyspnea Hx of paroxysmal nocturnal dyspnea. Severe apprehension, agitation, confusion— Resulting from hypoxia Feels like he/she is smothering Cyanosis— Diaphoresis— Results from sympathetic stimulation Pulmonary congestion Often present Rales—especially at the bases. Rhonchi—associated with fluid in the larger airways indicative of severe failure Wheezes—response to airway spasm Signs and Symptoms of LVF
Jugular Venous Distention—not directly related to LVF. • Comes from back pressure building from right heart into venous circulation • Vital Signs— • Significant increase in sympathetic discharge to compensate. • BP—elevated • Pulse rate—elevated to compensate for decreased stroke volume. • Respirations—rapid and labored
LOC— • may vary. • Depends on the level of hypoxia • Chest Pain • May in the presence of MI • Can be masked by the RDS.
REMEMBER LEFT VENTRICULAR FAILURE IS A TRUE LIFE THREATENING EMERGENCY
Etiology— Acute MI— Inferior MI Pulmonary disease COPD, fibrosis, HTN Cardiac disease involving the left or both ventricles Results from LVF Pathophysiology— Decreased right-sided cardiac output or increased pulmonary vascular resistance increased right vent. Pressures. As pressures rise, this increased pressure in the right atrium and venous system Higher right atrium pressures JVP Right Heart Failure
In the peripheral veins, pressures rise and the capillary pressures increase, hydrostatic pressure exceeds that of interstitial pressure • Fluid leaks from the capillaries into the surrounding tissues causing peripheral edema • Lungs are clear due to left ventricular pressures are normal
Marked JVD Clear chest Hypotension Marked peripheral edema Ascites, hepatomegaly Poor exercise tolerance The first three are for an inferior MI, describe cardiac tamponade. Often will be on Lasix, Digoxin, Have chronic pump failure Signs and Symptoms
Compensatory Mechanisms in CHF • Neurohormonal system • Renin-angiotensin-aldosterone system • Ventricular hypertrophy
Neurohormonal System • Stimulated by decreased perfusion secretion of hormones • Epi— • Increases contractility • Increases rate and pressure • Vasoconstriction SVR • Vasopressin— • Pituitary gland • Mild vasoconstriction, renal water retention
Renin-Angiotensin Mechanism • Decreased renal blood flow secondary to low cardiac output triggers renin secretion by the kidneys • Aldosterone is released increase in Na+ retention water retention • Preload increases • Worsening failure
Ventricular Hypertrophy • Long term compensatory mechanism • Increases in size due to increase in work load ie skeletal muscle
Drug Therapy • Aimed at diminishing the compensatory mechanisms of low cardiac output and also improving contractility • Vasodilators—ACE inhibitors • Diuretic agents • Inotropic agents
Dilate blood vessels Often constricted due to activation of the sympathetic nervous system and the renin-angiotensin-aldosterone system. Aka—ACE inhibitors Common ACE inhibitors Captopril Lisinopril Vasotec Monopril Accupril Nitrates Vasodilators
Diuretics • Lasix • Hydrochlorothiazide(HCTZ) • Spironolactone • These inhibit reabsorption of Na+ into the kidneys
Inotropic Agents • Digoxin • Lanoxin • Increases the contractility of the heart increasing the cardiac output
Nifedipine Diltiazem Verapamil Amlodipine Felodipine Used to dilate blood vessels Used mostly with CHF in the presence of ischemia Calcium Channel Blockers
Metoprolol Atenolol Propanolol Amiodarone Useful by blocking the beta-adrengergic receptors of the sympathetic nervous system, the heart rate and force of contractility are decreased could actually worsen CHF Beta Blockers
Prehospital Treatment • The prehospital goals for managing CHF • Promotion of rest • Relief of anxiety • Decreasing cardiac workload • Attainment of normal tissue perfusion
Promotion of Rest • DO NOT make these patient’s walk • Could start a fluid “rush” into the alveoli • Try to get them to sit still if they appear agitated and hypoxic
Relief of Anxiety • Often experienced • Leads to increase in O2 demand and cardiac workload • Explain what you are doing • MS 2 mg for treatment of anxiety and for decreasing preload
Decreasing Cardiac Workload • NTG • MS • Lasix • O2—High flow O2
Common Heart Failure Medications • ACE Inhibitors • Digitalis • Diuretics • Hydralazine • Nitrates
ACE Inhibitors • Prevent the production of the chemicals that causes blood vessels to narrow • Resulting in blood pressure decreasing and the heart pumping easier
Digitalis • Inotropic effects on the heart • Negative chronotropic effects
Diuretics • Decrease the body’s retention of salt and water • Reduces blood pressure • Probably will be on potassium
Hydralazine • Widens the blood vessels, therefore allowing more blood flow
Nitrates • Relaxation of smooth muscle • Widens blood vessels • Lowers systolic blood pressure
Diagnostic Challenges • Particularly difficult in elderly • Atypical presentations • Predominant symptoms include: • Anorexia • Generalized weakness • Fatigue • Mental disturbances • Anxiety