Congestive Heart Failure and Pulmonary Edema |
Coauthored by David FM Brown, MD, Assistant Chief, Instructor, Department of Emergency Medicine, Harvard Medical School, Massachusetts General Hospital
Shamai Grossman, MD, MS, is a member of the following medical societies: Society for Academic Emergency Medicine
Edited by William Chiang, MD, Assistant Director, Assistant Professor, Department of Emergency Medicine, Bellevue Hospital Center; Francisco Talavera, PharmD, PhD, Department of Pharmacy, Creighton University; Gary Setnik, MD, Chair, Assistant Professor, Department of Emergency Medicine, Harvard Medical School; John Halamka, MD, chief Information Officer/CareGroup Healthcare System, Assistant Professor of Medicine, Department of Emergency Medicine, Beth Israel Deaconess Medical Center; and Barry Brenner, MD, PhD, Vice-Chair, Director, Associate Clinical Professor, Department of Emergency Medicine, Division of Research, Cornell University, The Brooklyn Hospital Center
Author's Email: | Shamai Grossman, MD, MS | Topic Last Updated: |
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Editor's Email: | William Chiang, MD | 09/12/2000 16:45:27 |
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Background: Congestive heart failure (CHF) is an imbalance in pump function in which the heart fails to maintain the circulation of blood adequately. The most severe manifestation of CHF, pulmonary edema, develops when this imbalance causes an increase in lung fluid secondary to leakage from pulmonary capillaries into the interstitium and alveoli of the lung.
CHF can be categorized as forward or backward ventricular failure. Backward failure is secondary to elevated systemic venous pressure, while left ventricular failure is secondary to reduced forward flow into the aorta and systemic circulation. Furthermore, heart failure can be subdivided into systolic and diastolic dysfunction. Systolic dysfunction is characterized by a dilated left ventricle with impaired contractility, while diastolic dysfunction occurs in a normal or intact left ventricle with impaired ability to relax and receive as well as eject blood.
The New York Heart Association's functional classification of CHF is one of the most useful. Class I describes a patient who is not limited symptomatically by normal physical activity. Class II occurs when ordinary physical activity results in fatigue, dyspnea, or other symptoms. Class III is characterized by a marked limitation in normal physical activity. Class IV is defined by symptoms at rest or with any physical activity.
Pathophysiology: CHF is summarized best as an imbalance in Starling forces or an imbalance in the degree of end-diastolic fiber stretch proportional to the systolic mechanical work expended in an ensuing contraction. This imbalance may be characterized as a malfunction between the mechanisms that keep the interstitium and alveoli dry and the opposing forces that are responsible for fluid transfer to the interstitium.
Maintenance of plasma oncotic pressure (generally about 25 mm Hg) higher than pulmonary capillary pressure (about 7-12 mmHg), maintenance of connective tissue and cellular barriers relatively impermeable to plasma proteins, and maintenance of an extensive lymphatic system are the mechanisms that keep the interstitium and alveoli dry.
Opposing forces responsible for fluid transfer to the interstitium include pulmonary capillary pressure and plasma oncotic pressure. Under normal circumstances, when fluid is transferred into the lung interstitium with increased lymphatic flow, no increase in interstitial volume occurs. When the capacity of lymphatic drainage is exceeded, however, liquid accumulates in the interstitial spaces surrounding the bronchioles and lung vasculature, thus, 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.
Etiologies of pulmonary edema may be placed in the following 6 categories:
This chapter will limit itself to cardiac causes of pulmonary edema and CHF and its relevant emergency care.
Frequency:
Mortality/Morbidity:
Race:
Sex:
Age:
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History:
Physical:
Causes:
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Acute
Respiratory Distress Syndrome
Altitude Illness - Pulmonary
Syndromes
Anaphylaxis
Anemia, Acute
Bronchitis
Chronic Obstructive Pulmonary
Disease and Emphysema
Dysbarism
Hyperventilation Syndrome
Myopathies
Pericarditis and
Cardiac Tamponade
Pneumonia, Aspiration
Pneumonia,
Bacterial
Pneumonia, Immunocompromised
Pneumonia,
Mycoplasma
Pneumonia, Viral
Pneumothorax, Iatrogenic,
Spontaneous and Pneumomediastinum
Pulmonary Embolism
Shock, Septic
Venous Air Embolism
Other Problems to be Considered:
The cardiac patient with asthma or symptoms of chronic obstructive pulmonary disease (COPD) is a difficult clinical challenge.
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Lab Studies:
Imaging Studies:
Other Tests:
Procedures:
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Prehospital Care:
Emergency Department Care:
Consultations:
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The goal of pharmacotherapy is to achieve a PCWP of 15-18 mm Hg and a cardiac index > 2.2 L/min/m2, while maintaining adequate blood pressure and perfusion to essential organs. These goals may need to be modified for some patients.
Use of diuretics, nitrates, analgesics, and inotropic agents are indicated for the treatment of CHF and pulmonary edema. Calcium channel blockers, such as nifedipine and nondihydropyridines, increase mortality and increase incidence of recurrent CHF with chronic use. Conflicting evidence currently exists in favor, as well as against, the use of calcium channel blockers in the acute setting; at this time limit their acute use to patients with diastolic dysfunction and heart failure, a condition not easily determined in the ED.
Angiotensin converting enzyme (ACE) inhibitors, such as SL captopril or IV enalapril, may rapidly reverse hemodynamic instability and symptoms, possibly avoiding an otherwise imminent intubation. Haude compared 25 mg of SL captopril with 0.8 mg of sublingual nitroglycerin in 24 patients with class III and class IV CHF and found that captopril induces a more sustained and more pronounced improvement in hemodynamics. Annane gave 1 mg of IV enalapril to 20 patients presenting with acute class III and class IV CHF over 2 hours and demonstrated rapid hemodynamic improvement with no significant adverse affects on cardiac output or hepatosplanchnic measurements. Captopril may play a unique role in sustaining patients with renal failure and concomitant acute CHF while awaiting definitive therapy with dialysis. Since the information on this subject is still controversial and limited to small studies, their routine use cannot be recommended at this time. ACE inhibitors remain a promising area in need of further study.
Beta-blockers, possibly by restoring beta-1 receptor activity or via prevention of catecholamine activity, appear to be cardioprotective in patients with depressed left ventricular function. The US Carvedilol Heart Failure study group demonstrated a two-thirds decrease in mortality in patients taking carvedilol with left ventricular ejection fractions of 35% or less. Beta-blockers, particularly carvedilol, have been shown to improve symptoms in patients with moderate-to-severe heart failure. The role of beta-blockers in the acute setting, however, currently is unclear; limit use until hemodynamic studies indicate that further deterioration will not occur.
Because differentiating CHF and asthma exacerbations is often difficult, treating both with the shotgun approach often is employed, particularly as both may cause bronchospasm. Aerosolized beta-2 agonists, which are the more selective of beta agonists, decrease tachycardia, dysrhythmias, and cardiac work while transiently enhancing cardiac function. Terbutaline has been shown to be successful in this setting, as well as albuterol, isoetharine, and bitolterol.
Limit roles of theophyline and aminophylline in the acute setting. They are positive inotropic agents mediated by an increase in catecholamines, and they dilate coronaries and exert mild diuretic effects. Nevertheless, they can exacerbate dysrhythmias (eg, multifocal atrial tachycardia [MAT], ischemia) by increasing cardiac work.
Steroids, IV or PO, have been shown to worsen preexisting heart failure due to systemic sodium retention and volume expansion, hypokalemia, and occasional hypertension. Inhaled steroids, due to their lack of systemic side effects, may be a reasonable option in this confusing patient presentation; however, given their delayed onset of action, they remain an area in need of further study.
Please see the chapter on Asthma for
dosing schedules.
Drug Category: Diuretics - First-line therapy generally includes a loop diuretic such as furosemide, which will inhibit sodium chloride reabsorption in the ascending loop of Henle.
Drug Name | Furosemide (Lasix)- Administer loop diuretics IV, since this allows for both superior potency and a higher peak concentration despite increased incidence of side effects, particularly ototoxicity. |
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Adult Dose | A reasonable approach for furosemide might be as
follows: 10-20 mg IV for patients symptomatic with CHF not already using diuretics 40-80 mg IV for patients already using diuretics 80-120 mg IV for patients whose symptoms are refractory to the initial dose after 1 h of its administration Higher doses and more rapid redosing may be appropriate for the patient in severe distress. |
Contraindications | Documented hypersensitivity; hepatic coma; anuria; state of severe electrolyte depletion |
Interactions | Metformin decreases furosemide concentrations.
Conversely, furosemide interferes with the hypoglycemic effect of
antidiabetic agents. It also antagonizes the muscle relaxing effect of
tubocurarine. Auditory toxicity appears to be increased with concurrent use of aminoglycoside and furosemide. Hearing loss of varying degrees may occur. Anticoagulant activity of warfarin may be enhanced when taken concurrently with this medication. Increased plasma lithium levels and toxicity are possible when taken concurrently with this medication. |
Pregnancy | C - Safety for use during pregnancy has not been established. |
Precautions | Monitor for electrolyte imbalance. Exercise caution with coadministration of nephrotoxic drugs. |
Drug Name | Metolazone (Mykrox, Zaroxolyn)- Both chlorothiazide and metolazone have been used as adjunctive therapy in patients initially refractory to furosemide. Chlorothiazide, however, at doses of 250-500 mg IV, has been shown to decrease GFR with CHF and, thus, is less potent and causes a greater loss of potassium. Metolazone, on the other hand, repeatedly has been demonstrated to be synergistic with loop diuretics in treating refractory patients. |
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Adult Dose | 5-10 mg PO before redosing with furosemide |
Contraindications | Documented hypersensitivity; hepatic coma; encephalopathy; anuria |
Interactions | Thiazides may decrease effect of anticoagulants,
sulfonylureas, and gout medications. Anticholinergics and amphotericin B may increase toxicity of thiazides. Effects of thiazides may decrease when used concurrently with bile acid sequestrants, NSAIDs, and methenamine. When coadministered, thiazides increase toxicity of anesthetics, diazoxide, digitoxin, lithium, loop diuretics, antineoplastics, allopurinol, calcium salts, vitamin D, and nondepolarizing muscle relaxants. |
Pregnancy | B - Usually safe but benefits must outweigh the risks. |
Precautions | Exercise caution with hepatic and renal disease, diabetes mellitus, gout, and lupus erythematosus. |
Drug Name | Nitroglycerin (Nitro-Bid, Nitrol)- SL nitroglycerin
and Nitrospray are particularly useful in the patient who presents with
acute pulmonary edema with a systolic blood pressure of at least 100
mmHg. Similar to SL, Nitrospray’s onset is 1-3 min with a half-life of 5 min. The applicability of Nitrospray may be easier, and storage is up to 4 y. One study demonstrated significant and rapid hemodynamic improvement in 20 patients given Nitrospray with pulmonary edema in an ICU setting. Topical nitrate therapy is reasonable in a patient presenting with class I to II CHF. However, in patients with more severe signs of heart failure or pulmonary edema, IV nitroglycerin is preferred since it is easier to monitor hemodynamics and absorption, particularly in the diaphoretic patient. Oral nitrates, due to delayed absorption, have little role in the acute presentations of CHF. |
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Adult Dose | Nitrospray: single spray (0.4 mg) equivalent to a
single 1/150 SL; may repeat q3-5min as hemodynamics permit, up to a
maximum of 1.2 mg Ointment: Apply 1-2 inches of nitropaste to the chest wall Injection: start at 20 mcg/min IV and titrate to effect in 5-10 mcg increments q3-5min |
Contraindications | Documented hypersensitivity; severe anemia; shock; postural hypotension; head trauma; closed-angle glaucoma; cerebral hemorrhage |
Interactions | Aspirin may increase nitrate serum concentrations. Marked symptomatic orthostatic hypotension may occur when coadministered with calcium channel blockers, and an adjustment in the dose of either agent may be necessary. |
Pregnancy | C - Safety for use during pregnancy has not been established. |
Precautions | Exercise caution with coronary artery disease and low systolic blood pressure. |
Drug Name | Nitroprusside sodium (Nitropress)- Produces vasodilation and increases inotropic activity of the heart. At higher dosages it may exacerbate myocardial ischemia by increasing heart rate. It is easily titratable. |
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Adult Dose | 10-15 mcg/min and titrate to effective dose range of 30-50 mcg/min and a systolic blood pressure of at least 90 mmHg |
Contraindications | Documented hypersensitivity; subaortic stenosis; optic atrophy; tobacco amblyopia; idiopathic hypertrophic; atrial fibrillation or flutter |
Interactions | Patients receiving other hypertensive therapy may be more sensitive to sodium nitroprusside. |
Pregnancy | C - Safety for use during pregnancy has not been established. |
Precautions | Exercise caution with increased intracranial pressure,
hepatic failure, severe renal impairment, and hypothyroidism. In renal
or hepatic insufficiency, nitroprusside levels may increase and can
cause cyanide toxicity. Sodium nitroprusside has the ability to lower blood pressure; thus, use only in those patients with mean arterial pressures > 70 mm Hg. |
Drug Name | Morphine sulfate (Duramorph, Astramorph, MS Contin)-
DOC for narcotic analgesia due to reliable and predictable effects,
safety profile, and ease of reversibility with naloxone. Morphine sulfate administered IV may be dosed in a number of ways and commonly is titrated until desired effect is obtained. |
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Adult Dose | 2-5 mg and repeated q10-15min unless respiratory rate is < 20 breaths/min or systolic blood pressure is < 100 mmHg |
Contraindications | Documented hypersensitivity; hypotension; potentially compromised airway with uncertain rapid airway control; respiratory depression; nausea; emesis; constipation; urinary retention |
Interactions | Phenothiazine may antagonize analgesic effects of opiate agonists. Tricyclic antidepressants, MAO inhibitors, altered mental status, and other CNS depressants may potentiate adverse effects of morphine when used concurrently. |
Pregnancy | C - Safety for use during pregnancy has not been established. |
Precautions | Exercise caution with atrial flutter and other
supraventricular tachycardias. Morphine has vagolytic action and may increase the ventricular response rate. Due to the addictive nature of this drug, abuse is also a concern. |
Drug Name | Dopamine (Intropin)- Stimulates both adrenergic and
dopaminergic receptors. Its hemodynamic effects depend on the dose.
Lower doses stimulate mainly dopaminergic receptors that produce renal
and mesenteric vasodilation. Cardiac stimulation and renal vasodilation
is produced by higher doses. It is a positive inotropic agent at 2-10 mcg that can lead to tachycardia, ischemia, and dysrhythmias. Doses > 10 mcg cause vasoconstriction, which increases afterload. |
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Adult Dose | 5 mcg/kg/min and increase at 5 mcg/kg/min increments to a 20 mcg/kg/min dose |
Contraindications | Documented hypersensitivity; pheochromocytoma; ventricular fibrillation |
Interactions | Phenytoin, alpha- and beta-adrenergic blockers, general anesthesia, and MAO inhibitors increase and prolong effects of this medication; thus, lower the dosage. |
Pregnancy | C - Safety for use during pregnancy has not been established. |
Precautions | Monitor closely urine flow, cardiac output, pulmonary
wedge pressure, and blood pressure during infusion. Prior to infusion, correct hypovolemia with either whole blood or plasma, as indicated. Monitoring of central venous pressure or left ventricular filling pressure may be helpful in detecting and treating hypovolemia. |
Drug Name | Dobutamine (Dobutrex)- Produces vasodilation and increases inotropic state. At higher dosages it may cause increased heart rate, thus exacerbating myocardial ischemia. Strong inotropic agent with minimal chronotropic effect and no vasoconstriction. |
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Adult Dose | Starting dose: 2.5 mcg/kg/min; generally therapeutic in the range of 10-40 mcg/kg/min |
Contraindications | Documented hypersensitivity; idiopathic hypertrophic subaortic stenosis; atrial fibrillation or flutter |
Interactions | Beta-adrenergic blockers antagonize effects of nitroprusside. Conversely, general anesthetics may increase its toxicity. |
Pregnancy | C - Safety for use during pregnancy has not been established. |
Precautions | Following an MI use dobutamine with extreme caution. Correct a hypovolemic state before using this drug. |
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Further Inpatient Care:
Further Outpatient Care:
In/Out Patient Meds:
Transfer:
Deterrence/Prevention:
Complications:
Prognosis:
Patient Education:
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Medical/Legal Pitfalls:
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CME Question 1: A 45-year-old male with a history of chronic obstructive pulmonary disease (COPD) and an anterior myocardial infarction 1 year ago presents with complaints of sudden onset of cough, wheezing, and dyspnea. Physical exam is difficult, secondary to obesity but is significant for an oxygen saturation of 90%; a rapid, irregular heartbeat; and scattered wheezing and rhonchi in all lung fields. Symptoms persist despite 160 mg of IV furosemide. Which of the following would not be included in management of this patient?
A: Nasal continuous positive airway pressure
(CPAP)
B: IV digoxin
C: IV
morphine
D: Oral metolazone
E: Nebulized
albuterol
The correct answer is B: Digoxin has no role in the ED
management of CHF due to its delayed absorption and diminished efficacy at times
of increased sympathetic tone. It has little, if any, benefit in use in the
patient presenting concomitantly with atrial fibrillation and rapid ventricular
response. The use of digoxin should be limited to chronic CHF, where its role
has been well established.
CME Question 2: A 25-year-old alcoholic male is brought to the ED complaining that he just doesn't feel right. Which one of the following would not lead to the diagnosis of congestive heart failure (CHF)?
A: Cough productive of pink, frothy
sputum
B: Pulsus alternans
C: A
mid-to-late systolic murmur
D: A musical
wheeze
E: Pleuritic chest pain
The correct answer
is E: ED patients with CHF generally complain of dyspnea but often have
nonspecific complaints. Cough productive of pink, frothy sputum is highly
suggestive of CHF. On physical examination, patients often will be hypertensive
with pulsus alternans (alternating weak and strong pulse indicative of depressed
left ventricular [LV] function). Wheezing or rales may be heard on lung
auscultation. The apical impulse frequently is displaced, while cardiac
auscultation may reveal aortic or mitral valvular abnormalities, an S3 or S4.
Cardiac asthma is characterized by a high pitched or musical wheeze; however,
this is neither specific nor sensitive. This patient`s history of alcoholism
raises concerns of alcoholic cardiomyopathy, while his physical exam is
worrisome for critical aortic stenosis with CHF.
Pearl Question 1 (T/F): A 50-year-old male presents with shortness of breath, BP 200/110, and a heart rate of 100. His physical exam and chest x-ray are consistent with congestive heart failure (CHF) while the echocardiogram demonstrates normal left ventricular (LV) and valvular function. A beta-blocker may be helpful in this case.
The correct answer is True: Patients with diastolic dysfunction benefit most from beta-blockers and calcium channel blockers; diuretics are of more limited benefit.
Pearl Question 2 (T/F): An 80-year-old female from a third-world country just arrived in the US and presents with complaints of increasing difficulty of breathing over the past 2 weeks with minimal or no urine output. Her evaluation is consistent with severe congestive heart failure (CHF) and her creatinine is noted to be 10. One of the medical students suggests giving her a blocker or inhibitor or something to tide her over until dialysis can be arranged. No other additional treatment options are available.
The correct answer is False: Promising data exist suggesting that the use of SL captopril or IV enalapril may reverse hemodynamic instability and symptoms rapidly, possibly avoiding an otherwise imminent intubation. Recent data suggest that captopril may play a unique role in sustaining patients with renal failure and concomitant acute congestive heart failure while awaiting definitive therapy with dialysis. ACE inhibitors remain a promising area in need of further study.
Pearl Question 3 (T/F): A 75-year-old female presents with acute shortness of breath. Physical exam reveals jugular venous distention (JVD), an S3, and rales in all lung fields. Chest x-ray is clear. She is treated with diuretics, nitrates, and morphine with brisk diuresis and rapid improvement. Two days later, all symptoms have resolved and her physical exam is normal. Chest x-ray is repeated and read as consistent with pulmonary edema. These chest x-ray findings are not commonly seen in CHF.
The correct answer is False: Early congestive heart failure (CHF) may be manifest as cephalization of the pulmonary vessels. As the interstitial fluid accumulates, more advanced CHF may be demonstrated by Kerley B line, while pulmonary edema is seen as perihilar infiltrates, often in the classic butterfly pattern. However, several limitations to the use of chest x-ray in CHF exist. This classic radiographic progression often is not seen. As much as a 12-hour radiographic lag may occur from onset of symptoms, and radiographic findings frequently persist for several days despite clinical recovery.
Pearl Question 4 (T/F): A 95-year-old otherwise healthy male from Framingham, MA presents with his first episode of congestive heart failure (CHF). Median survival will be between 3-6 years.
The correct answer is True: Based on data from 4606 patients hospitalized with CHF between 1992-1993, total in-hospital mortality was 19%, with 30% of deaths occurring from noncardiac causes. These patients, however, were noted to have had suboptimal use of proven efficacious therapy, compared with those who survived hospitalizations, particularly among women and the elderly. Thirty-year data from the Framingham heart study demonstrated a median 5-year survival of 3.2 years for males and 5.4 years for females.
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Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this textbook have used their best efforts to provide information that is up-to-date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this text do not warrant the information in this text is accurate or complete, nor are they responsible for omissions or errors in the text or for the results of using this information. The reader should confirm the information in this text from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER |