Pulmonary edema resident survival guide: Difference between revisions

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==Prevention of pulmonary edema==
==Prevention of pulmonary edema==
Shown below is an algorithm depicting the management of stage A and B heart failure.<ref name="pmid23741057">{{cite journal| author=Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE, Drazner MH et al.| title=2013 ACCF/AHA guideline for the management of heart failure: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. | journal=Circulation | year= 2013 | volume= 128 | issue= 16 | pages= 1810-52 | pmid=23741057 | doi=10.1161/CIR.0b013e31829e8807 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23741057  }} </ref>
{{Family tree/start}}
{{Family tree | | | A01 | | | | | | | | | | A01= <div style="float: left; text-align: left; width: 25em; padding:1em;">'''Prevention of pulmonary edema''' </div>}}
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{{Family tree | B01 | | B02 | | B01= '''Cardiogenic pulmonary edema'''<br><div style="float: left; text-align: left; width: 25em; padding:1em;"> </div>| B02= '''Non-cardiogenic pulmonary edema''' <br> <div style="float: left; text-align: left; width: 25em; padding:1em;"></div>}}
{{Family tree | |,|-|-|-|^|-|-|-|.|| }}
{{Family tree | C01 | | C02 | | C03 | | | | C01= '''High altitude pulmonary edema'''<br><div style="float: left; text-align: left; width: 15em; padding:1em;"></div>|
C02= '''Acute respiratory distress syndrome'''<br> <div style="float: left; text-align: left; width: 25em; padding:1em;"></div>|C03= '''Neurogenic pulmonary edema'''<br><div style="float: left; text-align: left; width: 15em; padding:1em;"></div>}}
❑ Encourage healthy lifestyle and exercise<br>
❑ Precautions for pulmonary edema associated with high altitude<br>
**
❑  (I-A) <br>
❑ Control [[obesity]] (I-C) <br>
❑  (I-C) <br>
❑ Avoid tobacco (I-C) <br>
❑  <br>
❑  <br> </div>
| C02=<div style="float: left; text-align: left; width: 25em; padding:1em;">
❑ Encourage healthy lifestyle and exercise <br>
❑ Treat [[hypertension]] (I-A) <br>
❑ Treat [[dyslipidemia]] (I-A) <br>
❑ Control [[obesity]] (I-C) <br>
❑ Treat [[DM]] (I-C) <br>
❑ Avoid tobacco (I-C) <br>
❑ Avoid cardiotoxic agents (I-C)</div>}}
{{Family tree | | | | | |!| | | | | }}
{{Family tree | | | | | D01 | | | | D01=<div style="float: left; text-align: left; width: 25em; padding:1em;">
'''Consider additional measures in selected patients:'''
❑ Administer [[ACE-I]] if history of [[MI]] or [[ACS]] and reduced [[EF]] to prevent symptoms and reduce mortality (I-A), in all decreased [[EF]] to prevent symptoms (I-A) <br>
❑ Administer [[beta-blocker]]s if history of [[MI]] or [[ACS]] and reduced [[EF]] to reduce mortality (I-B), in all reduced [[EF]] to prevent symptoms (I-C) <br>
❑ Administer [[statin]]s if history of [[MI]] or [[ACS]] to prevent symptoms (I-A) <br>
❑ Consider [[ICD]] placement to prevent sudden death if asymptomatic ischemic [[cardiomyopathy]], > 40 days post-MI, [[LVEF]] ≤30%, on adequate medical therapy, and good 1 year survival</div>}}
{{Family tree/end}}





Revision as of 20:33, 14 March 2018


Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief:

Overview

This section provides a short and straight to the point overview of the disease or symptom. The first sentence of the overview must contain the name of the disease.

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

Common Causes

FIRE: Focused Initial Rapid Evaluation

A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients of pulmonary edema in need of immediate intervention.[1]

Boxes in red signify that an urgent management is needed.

Abbreviations: BU: Blood urea nitrogen; COPD: Chronic obstructive pulmonary disease; D5W: 5% dextrose solution in water ; HF: Heart failure; IV: Intravenous; MAP: Mean arterial pressure; Na: Sodium; NSAID: Non steroidal anti-inflammatory drug; SBP: Systolic blood pressure; S3: Third heart sound;

 
 
Identify cardinal findings that increase the pretest probability of pulmonary edema

Anxiety, restlessness
Dyspnea
Cool extremities/Warm extremities
Cough, particularly coughing up blood or bloody froth
❑Excessive sweating or diaphoresis
❑Grunting or gurgling sounds with breathing
❑Pale or blue skin
❑Blue or cyanotic lips
Orthopnea
Wheezing
Peripheral edema
Decreased urine output
❑ Pulmonary crepitations/rales/crackles
Third heart sound (S3) ❑ Past medical history of heart failure
❑ History of Opioid and aspirin overdose
❑ History of rapidly ascend to altitudes above 12,000 to 13,000 feet
❑ History of recent pulmonary embolism
❑ History of infections
❑ History of head injury, intracranial surgery, grand mal seizures, subarachnoid or intracerebral hemorrhage, and electroconvulsive therapy

❑ History of paroxysmal nocturnal dyspnea
 
 
 
 
 
 
 
 
 
Does the patient have any of the following findings that require hospitalization and urgent management?
Hypotension (SBP < 90 mmHg or drop in MAP >30 mmHg) and/or cardiogenic shock
Altered mental status
Cold and clammy extremities
Urine output <0.5mL/kg/hr

Dyspnea at rest manifested by tachypnea or oxygen saturation <90%
Atrial fibrillation with a rapid ventricular response resulting in hypotension

Acute coronary syndrome
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Yes
 
No
 
 
 
 
 
 
 
 
 
 
 
Admit to to a level of care that allows for constant ECG monitoring given the risk of arrhythmia and order a stat Chest Xray
 
 
 
 
 
 
 
 
 
 
 

Initial stabilization:
❑ Assess the airway
❑ Position the patient upright at an angle of 45 degrees, with legs dangling off the bedside (decrease preload)
❑ Monitor heart rate and blood pressure continuously
❑ Monitor oxygen saturation continuously
❑ If hypoxemia is present (Sa02 < 90% or Pa02 <60 mmHg), administer oxygen with/without noninvasive ventilation
Morphine to decrease symptoms and Afterload (avoid IV morphine, may increase mortality / duration of intubation, generally not advisable, may relieve refractory symptoms)
❑ Secure intravenous access with 18 gauge cannula
❑ Monitor fluid intake and urine output carefully (guide the adjustment of the diuretics dose)

Assess congestion and perfusion:
Congestion at rest (dry vs. wet)
"Wet" suggested by orthopnea, ↑JVP, rales, S3, pedal edema
Low perfusion at rest (warm vs. cold)
"Cold" suggested by narrow pulse pressure, cool extremities, hypotension
The patient is:
❑ Warm and dry, OR
❑ Warm and wet, OR
❑ Cold and dry, OR
❑ Cold and wet

Identify precipitating factor and treat accordingly:
Click on the precipitating factor for more details on the management
Myocardial infarction
Myocarditis
Renal failure
Hypertensive crisis
❑ Non adherence to medications
❑ Worsening Aortic stenosis
❑ Drugs (NSAIDS, thiazides, calcium channel blocker, beta blockers)
❑ Toxins (alcohol, anthracyclines)
Atrial fibrillation

Rate control of atrial fibrillation is the mainstay of arrhythmia therapy. Avoid the use of drugs with negative inotropic effects such as beta blockers and non-dihydropyridine calcium channel blockers e.g., verapamil in the treatment of acute decompensated systolic heart failure
Consider cardioversion if the patient is in cardiogenic shock or if new onset atrial fibrillation is the clear precipitant of the hemodynamic decompensation

COPD
Pulmonary embolism
Anemia
Thyroid abnormalities
❑ Systemic infection

❑ Opioid and aspirin overdose
❑ Recent pulmonary embolism
❑ Recent ascend from high altitude
❑ Head injury, intracranial surgery, grand mal seizures, subarachnoid or intracerebral hemorrhage, and electroconvulsive therapy

Treat congestion and optimize volume status:
Diuretics
❑ Administer IV loop diuretics as intermittent boluses or continuous infusion (I-B)

❑ If patient is already on loop diuretics: IV dose ≥ home PO dose (I-B); rule of thumb: IV dose = 2.5x equivalent oral daily dose
❑ If patient is not already on loop diuretics, administer IV starting dose:
Furosemide 20 to 40 mg, OR
Torsemide 5 to 10 mg, OR
Bumetanide 0.5 to 1 mg
❑ Adjust dose according to volume status (I-B)
❑ Perform serial assessment of fluid intake and output, vital signs, daily body weight (measured every day, with the same scale, at the same time, after first void) and symptoms
❑ Order daily electrolytes, BUN, creatinine (I-C)

❑ Low sodium diet (<2 g daily)
❑ In case of persistent symptoms:

❑ Increase dose of IV loop diuretics (I-B)- double dose at 2 hour interval up to maximal daily dose
Furosemide maximal dose: 40 to 80 mg
Torsemide maximal dose: 20 to 40 mg
Bumetanide maximal dose: 1 to 2 mg
OR
❑ Add a second diuretics, such as thiazide (I-B)

❑ Consider low dose dopamine infusion for improved diuresis and renal blood flow (IIb-B)
❑ Consider renal replacement therapy/ultrafiltration in obvious volume overload (IIb-B) refractory to higher dose/combination of IV diuretics

Venodilators
❑ Consider IV nitroglycerin, nitroprusside, or nesiritide as add-on to diuretics to relieve dyspnes (IIb-A)

Do not administer vesodilators among patients with hypotension.

Treat low perfusion:
Inotropes (click her for details)

If the total body and intravascular volumes are overloaded and the patient is normotensive, then diuresis alone should be undertaken. If the patient is volume overloaded but hypotensive, then inotropes must be administered in addition to diuretics.

Invasive hemodynamic monitoring:

❑ Consider pulmonary artery catheterization in case of failure to respond to medical therapy, respiratory distress, shock, uncertainty regarding volume status, or increase in creatinine; assess the following parameters:

PCWP
Cardiac output
Systemic vascular resistance

Pulmonary embolism:
Anticoagulation in the absence of contraindications (I-B)

Aspirin toxicity:
❑ Sodium bicarbonate is the treatment for aspirin toxicity usually common in elderly

Opioid overdose treatment
❑ Naloxone is used to reverse for opioid overdose

Infections treatment
❑ Start antibiotics depending upon the type of infections
Chronic medical therapy:
❑ Chronic ACE inhibitor: Hold if patient is hemodynamically unstable
❑ Chronic beta blocker:

Hold if patient is hemodynamically unstable and/or in need or inotropes
Decrease dose by ≥ half if patient is in moderate heart failure

❑ DO NOT INITIATE ACE INHIBITORS during an acute decompensation
❑ DO NOT INITIATE BETA BLOCKER during an acute decompensation; initiate beat blockers at a low dose in stable patients following optimization of volume status and D/C IV diuretics and inotropes (I-B)

Monitor laboratory tests:
❑CBC with differentials
❑ESR
❑Lactate
❑Urine toxins
❑Albumin
BUN
Creatinine
Sodium (to detect hyponatremia which carries a poor prognosis), chloride, bicarbonate (to detect contraction alkalosis) and serum potassium (to detect hypokalemia as a result of diuresis and which can precipitate arrhythmias), potassium, magnesium

Management of hyponatremia:
❑ Water restriction

❑ <2 L/day if the Na is < 130 meq/L
❑ < 1 L/day or more if the Na is < 125 meq/L
Keep in min that juices are essentially free water with sugar.
In the hyponatremia patient, drips should not be in D5W.

❑ Optimization of chronic home medications

❑ Persistent hyponatremia and risk of cognitive impairment: vasopressin antagonist for short term (hypervolemic)
 
 
 
 
 

Complete Diagnostic Approach

A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.

Abbreviations: ANA: Antinuclear antibody; ARDS: Acute respiratory distress syndrome; BNP: B-type natriuretic peptide; BUN: Blood urea nitrogen; CAD: Coronary artery disease; CBC: Complete blood count; CCB: Calcium channel blocker; CHF: Congestive heart failure; CT: Computed tomography; CXR: Chest X-ray; DM: Diabetes mellitus; ECG: Electrocardiogram; JVP: Jugular venous pressure; HF: Heart failure; HTN: Hypertension; LVEF: Left ventricular ejection fraction; LVH: Left ventricular hypertrophy; MI: Myocardial infarction; MRI: Magnetic resonance imaging; NT-pro BNP: N-terminal pro-brain natriuretic peptide; OCPs: Oral contraceptive pills; PAWP: Pulmonary artery wedge pressure; SBP: Systolic blood pressure; S1: First heart sound; S3: Third heart sound; TSH: Thyroid stimulating hormone

 
 
 
 
 
 
 
Characterize the symptoms:

Symptoms of Cardiogenic pulmonary edema
Anxiety, restlessness
Dyspnea

❑ At rest
❑ Exertional

Paroxysmal nocturnal dyspnea
Orthopnea
Cough
Excessive sweating or diaphoresis
Grunting or gurgling sounds with breathing
Pale or blue skin
Blue or cyanotic lips

Symptoms of Noncardiogenic pulmonary edema
❑ Symptoms of noncardiogenic pulmonary edema are similar to cardiogenic pulmonary edema, the only difference is the acute onset of symptoms after inciting event

Symptoms suggestive of precipitating events
Chest pain (suggestive of myocardial ischemia)
Palpitations (suggestive of arrhythmias)
Fever (suggestive of infection)
Seizures (suggestive of CNS insult)


Nonspecific symptoms
Nausea
Weight gain


Obtain a detailed history:
Past medical history

Atrial fibrillation
Cardiomyopathy
Diabetes mellitus
Hypertension
Myocarditis
Previous myocardial infarction
Prior heart failure
COPD
Valvular heart disease
Central nervous system injury

Medication history

❑ Noncompliance with previously prescribed medications for heart failure
❑ Intake of the following drugs:
Anticoagulants
Aspirin
Narcotics
Heroin
NSAID
Morphine
Methadone
Dextropropoxyphene

Family history

❑ History of dilated cardiomyopathy
Radiation to the chest

Surgical history

Recent surgery
Valve replacement surgeries

Recent history

Opioid and aspirin overdose
High altitudeascend
Pulmonary embolism
Head injury
Seizures
Electroconvulsive therapy


 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Examine the patient:

General appearance:
❑ Ill-looking
❑ In respiratory distress
❑ Inability to speak in full sentences

Vitals:
Temperature

Fever (suggestive of underlying infection)

Pulse

Tachycardia
Narrow pulse pressure (<25% of SBP)

Blood pressure

Hypotension (suggestive of circulatory collapse)
Hypertension

Respiration

Tachypnea (most common symptom)

Pulse oximetry (maintain oxygen sat ≥ 94% unless COPD)

Weight:
❑ Measure weight daily at the same time after the first void
❑ Subtract 'dry weight' from current weight to estimate extent of volume overload and edema

Skin
Cool and clammy (suggestive of hypoperfusion)
Cyanosis (suggestive of severe hypoxemia)
Anasarca
Jaundice (suggestive of liver dysfunction secondary to right-sided fluid overload)

Neck examination:
Jugular vein distention (suggestive of right-sided fluid overload)
❑ Positive hepatojugular reflux (suggestive of right-sided fluid overload)

Respiratory examination
Tachypnea
Wheeze
❑ Dullness at lung bases (suggestive of pleural effusion, may be present in chronic HF secondary to lymphatic compensation)
Crackles/crepitations/rales (suggestive of pleural effusion)
Cheyne-stokes respiration

Cardiovascular examination
❑ Displaced apex beat (suggestive of enlarged left ventricle)
Parasternal heave (suggestive of elevated right ventricular pressure)
S3 (typical) or S4 or both
❑ Soft S1
❑ Pulsus alternans
S4 (suggestive of diastolic dysfunction)
❑ New or changed murmur (suggestive of an underlying valvular heart diseases)

Mitral regurgitation - Holosystolic murmur
Aortic regurgitation - Decrescendo diastolic murmur
Aortic stenosis - Crescendo-decrescendo systolic ejection murmur with ejection click

Abdominal examination
The following findings suggest volume overload and / or poor forward cardiac output:
Hepatojugular reflux
Hepatomegaly
Ascites

Extremity examination
Pedal edema

Neurological examination
Altered mental status
Syncope (suggestive of aortic stenosis or pulmonary embolism)


Determine status of congestion and perfusion based on physical exam:
Congestion at rest (dry vs. wet)

"Wet" suggested by orthopnea, ↑JVP, positive hepatojugular reflux, abnormal valsalva response, rales, dullness upon percussion in bases, S3, peripheral edema, hepatomegaly, ascites, jaundice

Low perfusion at rest (warm vs. cold)

"Cold" suggested by narrow pulse pressure, cool extremities, hypotension, soft S1, pulsus alternans, decreased urinary output

The patient is:
❑ Warm and dry, OR
❑ Warm and wet, OR
❑ Cold and dry, OR
❑ Cold and wet

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Order tests:

Routine (Class I, level of evidence C)

CBC with differentials(rule out anemia and infections)
ESR
Lactate
❑ Urine toxicology
Troponin
❑ Elevated in myocardial ischemia and acute cardiogenic pulmonary edema, particularly if creatinine clearance (CrCl) is reduced
Troponin T ≥ 0.1 ng/mL (associated with poor survival)[2]
Electrolytes
Sodium: hyponatermia may occur due to fluid overlaod
Serum calcium
Serum magnesium can be lowered by diuresis
Serum bicarbonate: to monitor contraction alkalosis with diuresis
BUN, creatinine: may be elevated due to poor renal perfusion
Urinalysis
Fasting blood sugar
Fasting lipid profile
Liver function tests: can be elevated secondary to peripheral hypoperfusion
TSH

BNP or NT-pro BNP
Heart failure is unlikely if:[3][4]

BNP ≤ 100 pg/mL, or
NT-pro BNP ≤ 300 pg/mL

Chest X-ray of Cardiogenic pulmonary edema (Class I, level of evidence C)

Cardiomegaly (cardiothoracic ratio >50%)
❑ Cardiogenic pulmonary edema
Kerley B lines
Peribronchial cuffing
Cephalization

Chest X-ray findings of non-cardiogenic edema
❑Patchy alveolar infiltrates
❑ Air bronchograms

Chest X-ray findings in a patient with acute heart failure

ECG (to help identify the cause of heart failure)

Low QRS voltage (suggestive of infiltrative or dilated cardiomyoapthy)
Arrhythmia (atrial fibrillation carries a poor prognosis and requires slowing of the heart rate to improve filling & cardiac output)
Poor R wave progression (suggestive of a prior MI)
Left ventricular hypertrophy (consistent with a history of hypertension)
Left bundle branch block (LBBB) due to prior MI, may result in dysynchrony)
Left atrial enlargement (due to valvular disease or hypertension)
❑ Non-specific ST segment and T wave changes may suggest ischemia

❑ 2-D echocardiography with Doppler
(Class I, level of evidence C)

❑ Assess chambers size, wall thickness, wall motion, and valve function
❑ Assess ejection fraction

Radionuclide ventriculography or MRI

❑ To assess LVEF and volume when echocardiography is inadequate
❑ To assess myocardial infiltrative processes or scar burden (MRI)

Coronary angiography looking for CAD
❑ Comprehensive metabolic panel if no evidence of CAD on coronary angiography
❑ Consider pulmonary artery catheterization in case of failure to respond to medical therapy, respiratory distress, shock, uncertainty regarding volume status, or increase in creatinine; assess the following parameters:

PCWP
Cardiac output
Systemic vascular resistance

Order additional tests to rule out other etiologies:
ANA and rheumatoid factor (for rheumatologic diseases)
❑ Diagnostic tests for hemochromatosis and pheochromocytoma
Endomyocardial biopsy (when myocarditis is suspected)

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Consider alternative diagnoses:

Alternative diagnosesFeatures
Acute asthmaWheeze
❑ Reversal of symptoms following
administration of bronchodilators
COPD❑ Increased cough
❑ Increased dyspnea
❑ Increased sputum production
ARDS❑ Severe hypoxia
❑ Bilateral opacities on chest X-ray
PCWP < 15 mmHg
PneumoniaFever, cough, sputum
Consolidation on chest X-ray
Pulmonary embolismPleuritic chest pain, cough, S4
❑ Risk factors: trauma, immobilization, smoking, OCPs
❑ Clot in pulmonary artery on CT pulmonary angiography
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Assess the stage of heart failure using the ACCF/AHA staging system to guide chronic therapy
 
 


[1][5]

Prevention of pulmonary edema

 
 
Prevention of pulmonary edema
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Non-cardiogenic pulmonary edema
 
Cardiogenic pulmonary edema
 
 
 
 
 
 
 
 
 
 
 
 
 
 

❑ Encourage healthy lifestyle and exercise
❑ Precautions for pulmonary edema associated with high altitude

❑ ❑ (I-A)
❑ Control obesity (I-C)
❑ (I-C)
❑ Avoid tobacco (I-C)


 

❑ Encourage healthy lifestyle and exercise
❑ Treat hypertension (I-A)
❑ Treat dyslipidemia (I-A)
❑ Control obesity (I-C)
❑ Treat DM (I-C)
❑ Avoid tobacco (I-C)

❑ Avoid cardiotoxic agents (I-C)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Consider additional measures in selected patients: ❑ Administer ACE-I if history of MI or ACS and reduced EF to prevent symptoms and reduce mortality (I-A), in all decreased EF to prevent symptoms (I-A)
❑ Administer beta-blockers if history of MI or ACS and reduced EF to reduce mortality (I-B), in all reduced EF to prevent symptoms (I-C)
❑ Administer statins if history of MI or ACS to prevent symptoms (I-A)

❑ Consider ICD placement to prevent sudden death if asymptomatic ischemic cardiomyopathy, > 40 days post-MI, LVEF ≤30%, on adequate medical therapy, and good 1 year survival
 
 
 

References

  1. 1.0 1.1 Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE, Drazner MH; et al. (2013). "2013 ACCF/AHA guideline for the management of heart failure: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 128 (16): 1810–52. doi:10.1161/CIR.0b013e31829e8807. PMID 23741057.
  2. Perna, ER.; Macín, SM.; Parras, JI.; Pantich, R.; Farías, EF.; Badaracco, JR.; Jantus, E.; Medina, F.; Brizuela, M. (2002). "Cardiac troponin T levels are associated with poor short- and long-term prognosis in patients with acute cardiogenic pulmonary edema". Am Heart J. 143 (5): 814–20. PMID 12040342. Unknown parameter |month= ignored (help)
  3. McMurray JJ, Adamopoulos S, Anker SD, Auricchio A, Böhm M, Dickstein K; et al. (2012). "ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC". Eur Heart J. 33 (14): 1787–847. doi:10.1093/eurheartj/ehs104. PMID 22611136.
  4. Fuat A, Murphy JJ, Hungin AP, Curry J, Mehrzad AA, Hetherington A; et al. (2006). "The diagnostic accuracy and utility of a B-type natriuretic peptide test in a community population of patients with suspected heart failure". Br J Gen Pract. 56 (526): 327–33. PMC 1837840. PMID 16638247.
  5. Hunt SA, Abraham WT, Chin MH, Feldman AM, Francis GS, Ganiats TG; et al. (2009). "2009 Focused update incorporated into the ACC/AHA 2005 Guidelines for the Diagnosis and Management of Heart Failure in Adults A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines Developed in Collaboration With the International Society for Heart and Lung Transplantation". J Am Coll Cardiol. 53 (15): e1–e90. doi:10.1016/j.jacc.2008.11.013. PMID 19358937.