Pulmonary edema is a clinical term that refers to the abnormal buildup of fluids within the lung tissues that causes physiological disturbances to the patient. Patients usually present with severe left sided heart failure with pulmonary hypertension and alveolar flooding in the lungs.
Presentation
Pulmonary edema from different causes can either present acutely or chronically. The following signs and symptoms are commonly seen with pulmonary edema:
- Acute dyspnea
- Wheezing of lung fields
- Feeling of suffocation and drowning
- Restlessness and severe anxiety
- Productive cough (could be blood tinged)
- Palpitations and chest pain
- Exercise induced dyspnea
- Orthostatic dyspnea (dyspnea while lying down)
- Increased weight
- Bipedal edema
- Fatigue
- Fever
- Headache and dizziness
- Grayish blue skin tone
Entire Body System
- Fatigue
There is no shortness of breath at rest, no severe fatigue. Normal oxygen saturations (for the altitude) will be measured if a pulse oximeter is available. Pneumonia can be difficult to distinguish from HAPE. [basecampmd.com]
You may experience: shortness of breath, chest discomfort, heart palpitations, coughing, difficulty walking uphill, fatigue, fever, or headaches. [lungmds.com]
Further questioning revealed a history of nocturnal snoring, frequent awakening, and daytime fatigue, suggesting a possible sleep apnea syndrome (SAS). [edm.bioscientifica.com]
Both can cause a feeling of fatigue and make sleeping difficult. A rapid irregular heartbeat is also common in both conditions. Both of these conditions can be life-threatening if left untreated. [livestrong.com]
- Malaise
Symptomen: subklinisch of acuut koorts, hoofdpijn en malaise, daarna misselijkheid, braken en pijn in buik en lage rug (toxische fase). [lci.rivm.nl]
Respiratoric
- Cough
This case describes a patient with no prior history of HAPE and extensive experience hiking above 2,500 meters who developed progressive dyspnea and cough while ascending to 3,200 meters. [ncbi.nlm.nih.gov]
Tachycardia Orthopnea Distended Jugular veins Noisy, wet respirations that do not clear with coughing. Cough with Frothy, blood-tinged sputum. 7. [slideshare.net]
Associated symptoms included cough, weakness, expectoration of froth, chest discomfort, orthopnea, wheezing, hemoptysis, and dizziness. [archive.rubicon-foundation.org]
Initially, pulmonary edema may cause a dry cough; however, when edema progresses to the point that alveoli are flooded, the cough can become productive, characterized by a pinkish sputum. [pathwaymedicine.org]
- Dyspnea
[…] induced dyspnea Orthostatic dyspnea (dyspnea while lying down) Increased weight Bipedal edema Fatigue Fever Headache and dizziness Grayish blue skin tone Pulmonary edema is a medical emergency, thus initial diagnostic modalities are usually limited to [symptoma.com]
High altitude pulmonary edema (HAPE) is a form of high altitude illness characterized by cough, dyspnea upon exertion progressing to dyspnea at rest and eventual death, seen in patients who ascend over 2,500 meters, particularly if that ascent is rapid [ncbi.nlm.nih.gov]
Pulmonary edema typically results in dyspnea. When edematous fluid is large in volume it can redistribute when an individual lies supine, affecting more lung tissue and thus worsening dyspnea, a phenomenon known as orthopnea. [pathwaymedicine.org]
- Pneumonia
While both pulmonary edema and pneumonia cause a form of buildup in the lungs, the former is primarily caused by CHF. Pneumonia, on the other hand, is caused by an infection. [healthline.com]
Five patients (42%) developed pneumonia, and we postponed extubation until recovery from pneumonia. The cause for severe disability and death was symptomatic vasospasm and primary brain damage. No patients had rebleeding from ruptured aneurysms. [ncbi.nlm.nih.gov]
Tens of thousands of people in the U.S. die from pneumonia every year, most of them adults over the age of 65. What Causes Pneumonia? Pneumonia can be caused by a wide variety of bacteria, viruses and fungi in the air we breathe. [lung.org]
Pulmonary edema can overlap with pneumonia, but it is a different condition. Pneumonia is an infection that often occurs as a complication of a respiratory infection, such as the flu. It can be difficult to distinguish between the two. [medicalnewstoday.com]
- Orthopnea
In conclusion, while dyspnea and pretibial edema are often noted during normal pregnancies, the potential for PPCMP should be considered if these symptoms are excessive and/or comorbid paroxysmal nocturnal dyspnea and orthopnea are present, even in patients [ncbi.nlm.nih.gov]
Outcome and follow-up Over the course of 2 weeks, the shortness of breath and orthopnea subsided gradually and by the fourth night, the patient was able to sleep on one pillow with no orthopnea. [edm.bioscientifica.com]
Associated symptoms included cough, weakness, expectoration of froth, chest discomfort, orthopnea, wheezing, hemoptysis, and dizziness. [archive.rubicon-foundation.org]
When edematous fluid is large in volume it can redistribute when an individual lies supine, affecting more lung tissue and thus worsening dyspnea, a phenomenon known as orthopnea. [pathwaymedicine.org]
- Rales
However, the patient developed pink frothy sputum with diffuse bilateral rales 30 min later after transported to surgical intensive care unit (SICU). Negative pressure pulmonary edema. [ncbi.nlm.nih.gov]
Chest auscultation reveals rales and rhonchi bilaterally. A chest radiograph shows bilateral pulmonary infiltrates consistent with pulmonary edema and borderline enlargement of the cardiac silhouette. [doi.org]
Jaw & Teeth
- Foaming at the Mouth
The clinical presentation of pulmonary edema includes: acute breathlessness orthopnea paroxysmal nocturnal dyspnea foaming at the mouth distress One method of classifying pulmonary edema is as four main categories on the basis of pathophysiology which [radiopaedia.org]
Cardiovascular
- Heart Disease
This heart disease is associated with echocardiography systolic dysfunction and left ventricular dilatation. [ncbi.nlm.nih.gov]
An electrocardiogram and an echocardiogram are often quite helpful in detecting underlying heart disease. If heart disease is suspected but cannot be demonstrated by noninvasive testing, a cardiac catheterization may be necessary. [verywellhealth.com]
This mechanism may occur with many cardiac diseases, such as arrhythmia, heart disease, heart failure ; a trauma causing a rupture of the membrane between the vessels and alveoli: we speak in this case of ARDS (acute respiratory distress syndrome). [health.ccm.net]
- Tachycardia
In both procedures, patients developed severe hypertension and tachycardia, with subsequent oxygen desaturations with noted pulmonary edema. [ncbi.nlm.nih.gov]
She subsequently developed agitation, increasing tachypnea and tachycardia, and a persistent cough. Her lungs had diffuse crackles and rhonchi. O[sub]2[/sub] saturation was 85% in room air. [professional.diabetes.org]
If the pulmonary edema is associated with severe tachycardia (or AF and electrical cardioversion failed), pharmacologic rate (and rhythm) control is essential in AS. [casesjournal.biomedcentral.com]
- Hypotension
Precipitous hypotension is hard to reverse, so use is best reserved for longer term management of HF. [lifeinthefastlane.com]
However, its use continues to be controversial due to concerns of drug induced hypotension, syncope or paresthesia. [ncbi.nlm.nih.gov]
Reduce preload: Seat pt upright to reduce venous return, if not hypotensive. Intravenous loop diuretic (e.g., furosemide, initially 0.5–1.0 mg/kg); use lower dose if pt does not take diuretics chronically. [accessmedicine.mhmedical.com]
- Cyanosis
The accumulation of fluids in the lungs fill in the air sacs and manifest externally dyspnea, chest pain, and cyanosis. [symptoma.com]
In severe degrees of edema the breathing is that of suffocation, there is cyanosis, and there exudes or is expectorated from the mouth a thin serous frothy fluid often tinged with blood. [jamanetwork.com]
[…] trauma Cardiopulmonary bypass Possible Lung Injury Plus Elevated Hydrostatic Pressures High-altitude pulmonary edema Reexpansion pulmonary edema Neurogenic pulmonary edema Pt appears severely ill, often diaphoretic, sitting bolt upright, tachypneic, and cyanosis [accessmedicine.mhmedical.com]
Accumulation of fluid in the interstitium and alveoli results in varying degrees of respiratory distress and cyanosis due to reduced oxygen transport into pulmonary capillaries. [vetstream.com]
(tachycardia) Rapid breathing (tachypnea) Other things that may be seen during the exam include: Leg or abdominal swelling Abnormalities of your neck veins (which can show that there is too much fluid in your body) Pale or blue skin color (pallor or cyanosis [medlineplus.gov]
- Palpitations
For those with pulmonary edema though, the lungs begin to fill up with fluid instead of air, resulting in a shortness of breath, heart palpitations, and in severe cases a bloody cough. [everydayhealth.com]
The following signs and symptoms are commonly seen with pulmonary edema: Acute dyspnea Wheezing of lung fields Feeling of suffocation and drowning Restlessness and severe anxiety Productive cough (could be blood tinged) Palpitations and chest pain Exercise [symptoma.com]
Sudden pulmonary edema also may be accompanied by extreme anxiety and palpitations. Sudden-onset pulmonary edema is often called “flash pulmonary edema,” and it most often indicates a sudden worsening of an underlying cardiac problem. [verywellhealth.com]
[…] with breathing difficulties, other signs and symptoms of acute pulmonary edema can include: cough, often with a pink frothy sputum excessive sweating anxiety and restlessness feelings of suffocation pale skin wheezing rapid or irregular heart rhythm (palpitations [medicalnewstoday.com]
Urogenital
- Oliguria
It was interesting to note that oliguria persisted in Case 2 after 500 mg frusemide when there was a mean pulmonary capillary wedge pressure (PCWP) of 13 cm H2O but following subsequent elevation of the PCWP to 16 cm H2O with plasma there was an immediate [inchem.org]
Neurologic
- Headache
We present a case of a 31-year-old Caucasian woman with a history of hypertension and recurrent occipital headaches who was admitted to the emergency department due to severe de novo AHF presenting as pulmonary edema and cardiogenic shock. [ncbi.nlm.nih.gov]
A severe headache, vomiting and lethargy will progress to unsteadiness, confusion, drowsiness and ultimately coma. HACE can kill in only a few hours. [altitude.org]
Feeling of suffocation and drowning Restlessness and severe anxiety Productive cough (could be blood tinged) Palpitations and chest pain Exercise induced dyspnea Orthostatic dyspnea (dyspnea while lying down) Increased weight Bipedal edema Fatigue Fever Headache [symptoma.com]
Assess for signs of hypoxia: restlessness, confusion, headache. 22. Monitor ECG for dysrrhythmia development that may be related to hypoxemia, acid-base imbalance, or ventricular irritability. [slideshare.net]
Mountain climbers should get to lower ground and seek medical attention if they have: Chest discomfort Cough Cough with frothy spit that may have some blood in it Fast, irregular heartbeat Fever Headache Shortness of breath when they’re active that gets [webmd.com]
- Dizziness
Associated symptoms included cough, weakness, expectoration of froth, chest discomfort, orthopnea, wheezing, hemoptysis, and dizziness. [ncbi.nlm.nih.gov]
Dyspnea, orthopnea, dizziness, syncope and pulmonary edema are examples of symptoms resulting from intracardiac obstructions, depending on the size, mobility and localization of the tumor. [atif.sobiad.com]
[…] suffocation and drowning Restlessness and severe anxiety Productive cough (could be blood tinged) Palpitations and chest pain Exercise induced dyspnea Orthostatic dyspnea (dyspnea while lying down) Increased weight Bipedal edema Fatigue Fever Headache and dizziness [symptoma.com]
[…] any of these symptoms, call 911 right away: Sudden shortness of breath Trouble breathing with a lot of sweating Breathing that sounds bubbly or like wheezing or gasping Coughing up pink, frothy spit Skin that looks blue or gray Feeling lightheaded, dizzy [webmd.com]
- Agitation
She subsequently developed agitation, increasing tachypnea and tachycardia, and a persistent cough. Her lungs had diffuse crackles and rhonchi. O[sub]2[/sub] saturation was 85% in room air. [professional.diabetes.org]
As their hypoxia worsens they may become agitated and with worsening respiratory failure may become hypercapnoeic causing their conscious level to fall. [rcemlearning.co.uk]
100 - 100.9 °F 10 Points 38.4 - 38.8 °C 101 - 101.9 °F 15 Punkte 38.9 - 39.4 °C 102 - 102.9 °F 20 Points 39.5 - 39.9 °C 103 - 103.9 °F 25 Points >= 40 °C >= 104 °F 30 Points 2.2 Central Nervous Effects Symptoms Points Missing 0 Points Mild (agitation [flexikon.doccheck.com]
In acute pulmonary edema, the patient may be extremely fearful or agitated. Breathlessness, dizziness, and faintness are common complaints. [tele.med.ru]
Ten minutes after her arrival to the PACU the patient became agitated, developed dyspnea, tachypnea (RR > 20 bpm), cyanosis, productive cough with the elimination of large amounts of pink-reddish secretion. [scielo.br]
Workup
Pulmonary edema is a medical emergency, thus initial diagnostic modalities are usually limited to the preliminary physical examination, chest X-ray, and electrocardiography (ECG). When patients are judged to be stable, they will be subjected to the different test and diagnostic procedures as a standard work up for pulmonary edema. The following tests are conducted to patients with pulmonary edema:
- Chest X-ray
- Pulse oximetry
- Blood tests
- ECG
- Echocardiography
- Transesophageal echocardiography (TEE)
- Pulmonary artery and cardiac catheterization
Cardiac Catheterization
- Pulmonary Arterial Pressure Increased
Systolic pulmonary artery pressure increased at high altitude, but normalised with sildenafil. The altitude-induced decrease in maximal O 2 consumption was significantly smaller with sildenafil than with placebo. [doi.org]
X-Ray
- Kerley B Lines
The early signs of pulmonary edema (interstitial edema) are the septal lines (Kerley B lines), which are horizontal lines seen laterally in the lower zones. [emedicine.com]
On a CXR, cardiogenic pulmonary edema can show; cephalization of the pulmonary vessels, Kerley B lines or septal lines, peribronchial cuffing, "bat wing" pattern, patchy shadowing with air bronchograms, and increased cardiac size. [med-ed.virginia.edu]
전해질 정상 고칼륨혈증 심한 심박출량 저하시 혈액요소질소(BUN) 및 크레아티닌(Cr) 중증 심부전에서는 증가 심장효소 리파제 동맥혈가스분석검사 영상검사 가슴방사선 사진 3단계의 변화를 보인다. pulmonary redistribution Cephalization of vessels 간질성 부종(interstitial edema) 늑막삼출 컬리 B선(Kerley B lines) 나비모양 침윤(Classic butterfly infiltrate) [clinicclinic2.cafe24.com]
Other features of cardiogenic pulmonary edema include elevated cardiac enzymes and enlarged cardiac silhouette or the presence of Kerley B lines in CXR (3). [edm.bioscientifica.com]
- Pulmonary Infiltrate
Computed tomography scan of the chest showed diffuse ground glass infiltrates and dilated pulmonary vessels in the right lung in addition to bilateral pulmonary masses with obstruction of the left main pulmonary bronchus. [ncbi.nlm.nih.gov]
A chest radiograph shows bilateral pulmonary infiltrates consistent with pulmonary edema and borderline enlargement of the cardiac silhouette. [doi.org]
- Pulmonary Infiltrates
Computed tomography scan of the chest showed diffuse ground glass infiltrates and dilated pulmonary vessels in the right lung in addition to bilateral pulmonary masses with obstruction of the left main pulmonary bronchus. [ncbi.nlm.nih.gov]
A chest radiograph shows bilateral pulmonary infiltrates consistent with pulmonary edema and borderline enlargement of the cardiac silhouette. [doi.org]
- Bilateral Pulmonary Infiltrates
Chest auscultation reveals rales and rhonchi bilaterally. A chest radiograph shows bilateral pulmonary infiltrates consistent with pulmonary edema and borderline enlargement of the cardiac silhouette. [doi.org]
- Atelectasis
The anesthesiologists should determine appropriate anesthetic regimens according to the examination results to avoid acute atelectasis and postoperative pulmonary edema. [ncbi.nlm.nih.gov]
Lung consolidations may have a variety of causes including infection, pulmonary embolism, lung cancer and metastasis, compression atelectasis, obstructive atelectasis, and lung contusion. [doi.org]
QRS Wave
- Poor R Wave Progression
An electrocardiogram showed ST depression in leads V5–V6 and poor R wave progression in leads V1–V4. Her chest X-ray revealed alveolar-interstitial infiltrates and a fluid collection around horizontal fissure in her right lung (Fig. 1). [jmedicalcasereports.biomedcentral.com]
Serum
- Hypercapnia
With progressive respiratory failure, hypercapnia develops with acidemia. CXR shows pulmonary vascular redistribution, diffuse haziness in lung fields with perihilar “butterfly” appearance. [accessmedicine.mhmedical.com]
Non-invasive ventilation should be considered in dyspnoeic patients with pulmonary oedema and a respiratory rate >20 breaths/minute to improve breathlessness and reduce hypercapnia and acidosis. [patient.info]
Monitor ABG results for presence of hypoxemia(decrease PaO2) and hypercapnia(Increase PcO2) 21. Assess for signs of hypoxia: restlessness, confusion, headache. 22. [slideshare.net]
Care is required when giving oxygen if the patient has lung disease as oxygen can reduce respiratory drive causing hypercapnia (respiratory failure). [doi.org]
- Oxygen Saturation Decreased
Dyspnea, decrease of blood pressure, tachycardia, tachypnoe and expectoration of pink sputum were recorded after negative pressure application. Oxygen saturation decreased to 90% despite the addition of oxygen. [medvik.cz]
Immediately after extubation, the patient developed inspiratory stridor consistent with laryngospasm; the anesthesiologist had difficulty in mask ventilating the patient, and peripheral oxygen saturation decreased to less than 80%. [anesthesiology.pubs.asahq.org]
Firstly, as pulmonary congestion increases, oxygen saturation decreases, resulting in decreased myocardial oxygen supply. This leads to ischaemia in regions with already borderline blood supply, further impairing cardiac performance. [pmj.bmj.com]
Treatment
Patients presenting with pulmonary edema are usually attached to an oxygen source through mask or nasal cannula to allay the symptoms of dyspnea. Although severe cases presenting with respiratory failure may already require mechanical ventilation [9]. For cardiogenic pulmonary edema, a cardiac preload unloader like furosemide can reduce the accumulation of fluids in the air sacs. In the same way, an afterload reducer like nitroprusside that dilates the systemic vessels and unloads the ventricular workload can mitigate the crisis. Morphine is sometimes given to control chest pain and severe anxiety in patients. Blood pressure regulating medications may also be given with the need arise during the resuscitative phase of pulmonary edema.
Prognosis
The prognosis for patients who subsequently develop congestive heart failure with hydrostatic pulmonary edema is poor. It carries a mean survival time of 1.7 years among males and 3.2 years in females from the time of diagnosis [7]. Most cases of neurogenic pulmonary edema remains underdiagnosed due to the imposing primary disorder that undermines its existence. The relative morbidity of neurogenic pulmonary edema is as high as 50% while its relative mortality rating is as low as 7% [8].
Etiology
The following etiologic factors and medical conditions predispose susceptible patients to pulmonary edema:
- Coronary heart disease
- Cardiomyopathy
- Cardiac valvular diseases
- Hypertension
- Acute respiratory distress syndrome (ARDS)
- Barotrauma in high altitudes
- Drug reactions
- Viral infections
- Intracerebral and subarachnoid hemorrhage [1]
- Seizure disorder [2]
- Pulmonary embolism
- Lung trauma
- Toxins
- Inhalation injuries
- Near drowning
Epidemiology
The American Heart Association (AHA) has reported at 550,000 new cases of cardiogenic pulmonary edema each year in the United States. Congestive heart failure has caused the death of at least 287,000 of these cases in 1999 alone [3]. The lifetime risk for hydrostatic pulmonary edema has practically doubled beyond 40 years of age especially those with hypertension concomitant with congestive heart failure [4].
There is a slight predilection for the male population compared to the females due to the decreasing incidence of cardiogenic and neurogenic inciting events among females. In neurogenic pulmonary edema, more than half of patients have sustained a blunt trauma to the head with concussion. More than 71% of patient fatalities with subarachnoid hemorrhage complicates with neurogenic pulmonary edema. In at least of a third of the patients with status epilepticus develop neurogenic pulmonary edema [5].
Pathophysiology
The accumulation of the fluid within the alveoli is commonly brought about by cardiogenic causes. In the normal flow of blood, the atria receives the blood from the lungs where it is pumped outward by the left ventricle to the other organs of the body. Any pathology that endangers this balance and causes an increased pressure in the atria can cause a backflow of fluids to the air sacs due to the increased in ventricular and atrial pressure. Heart related pathologies that results in cardiogenic pulmonary edema include coronary artery diseases, cardiomyopathy, hypertension, and cardiac valvular problems. In non-cardiogenic pulmonary edema however, the capillaries within the lungs become more permeable or “leaky” due to inflammatory responses with infection, bleeding, and pressure. This are usually brought about by toxins, medications, contrast media [6], viral infections, barotrauma, near drowning, and neurogenic disorders.
Prevention
The active control of the congestive heart failure is paramount in the prevention of the hydrostatic pulmonary edema. Lung infections like pneumonia must be treated promptly and monitored to prevent progressive accumulation of fluids within the lung spaces. Adequate acclimatization should be in place for high altitude athletes to prevent the occurrence of pulmonary edema. A preventive dose of the corticosteroid dexamethasone may avert the progression to pulmonary edema of patients diagnosed with pulmonary hypertension and barotrauma [10].
Summary
Pulmonary edema is a medical condition wherein there is an excessive fluid in the pulmonary space. The accumulating fluid in the lungs fills in the air sacs and manifest externally as dyspnea. Pulmonary edema is most commonly caused by heart failure although some non-cardiac causes like pulmonary infections, reactions to medications, external trauma, barotrauma from high altitudes, and toxins may predispose patients to this serious lung disorder. Pulmonary edema which occurs acutely is considered a serious medical emergency that could be potentially fatal if not treated immediately.
Patient Information
Definition
Pulmonary edema is a medical condition wherein there is an abnormal accumulation of fluid (exudates) in the alveoli. The accumulation of fluids in the lungs fill in the air sacs and manifest externally dyspnea, chest pain, and cyanosis.
Cause
The majority of cases of pulmonary edema are caused by cardiogenic factors like congestive heart failure, cardiomyopathy and valvular diseases. Non-cardiogenic causes include pneumonia, toxins, medications, and barotrauma.
Symptoms
Patients usually present with dyspnea, chest pain, signs of cyanosis, productive cough of red tinged sputum, and severe anxiety with restlessness.
Diagnosis
Preliminary physical examination, ECG and Chest X-ray are routinely done in an emergency setting for patients suspected of pulmonary edema. Additional tests like pulse oximetry, blood tests, echocardiography, and pulmonary/cardiac catheterization are performed as soon as the patients are stabilized.
Treatment and follow-up
Oxygen inhalation is the primary intervention given to patients with pulmonary edema. Cardiogenic pulmonary edema patients are given preload unloaders and afterload reducers to allay the cardiogenic instability. Morphine may also be given to relieve the chest pain and severe anxiety in patients.
References
- Muroi C, Keller M, Pangalu A, Fortunati M, Yonekawa Y, Keller E. Neurogenic pulmonary edema in patients with subarachnoid hemorrhage. J Neurosurg Anesthesiol. Jul 2008; 20(3):188-92.
- Baumann A, Audibert G, McDonnell J, Mertes PM. Neurogenic pulmonary edema. Acta Anaesthesiol Scand. Apr 2007; 51(4):447-55.
- Levy D, Kenchaiah S, Larson MG, et al. Long-term trends in the incidence of and survival with heart failure. N Engl J Med 2002; 347:1397–402.
- Lloyd-Jones DM, Larson MG, Leip EP, et al. Lifetime risk for developing congestive heart failure: the Framingham Heart Study. Circulation 2002; 106:3068–72.
- Reuter-Rice K, Duthie S, Hamrick J. Neurogenic pulmonary edema associated with pediatric status epilepticus. Pediatr Emerg Care. Oct 2011; 27(10):957-8.
- Demirhan A, Yasar Tekelioglu U, Akkaya A, Dagistan E, Suzi Ayhan S, Ozturk S. Magnetic resonance imaging contrast agent related pulmonary edema: a case report. Eur Rev Med Pharmacol Sci. Oct 2012; 16 Suppl 4:110-2.
- Lloyd-Jones DM. The risk of congestive heart failure: sobering lessons from the Framingham Heart Study. Curr Cardiol Rep 2001; 3:184–90.
- Piazza O, Venditto A, Tufano R. Neurogenic pulmonary edema in subarachnoid hemorrage. Panminerva Med. Sep 2011; 53(3):203-10.
- LHer E, Duquesne F, Girou E, de Rosiere XD, Le Conte P, Renault S, et al. Noninvasive continuous positive airway pressure in elderly cardiogenic pulmonary edema patients. Intensive Care Med. May 2004; 30(5):882-8.
- Perimenis P. Sildenafil for the treatment of altitude-induced hypoxaemia. Expert Opin Pharmacother 2005 6 (5): 835–7.