Negative-pressure pulmonary edema

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Negative-pressure pulmonary edema (NPPE), also known as Postobstructive Pulmonary Edema, is a clinical phenomenon that results from the generation of large negative pressures in the airways during attempted inspiration against some form of obstruction of the upper airways. [1] [2] [3] The most common reported cause of NPPE reported in adults is laryngospasm, while the most implicated causes in children are infectious croup and epiglottitis. The large negative pressures created in the airways by inhalation against an upper airway obstruction can lead to fluid being drawn from blood vessels supplying the lungs into the alveoli, causing pulmonary edema and impaired ability for oxygen exchange (hypoxemia). [4] The main treatment for NPPE is supportive care in an intensive care unit and can be fatal without intervention. [1] [2]

Contents

Physiology

NPPE develops as a result of significant negative pressure generated in the chest cavity by inspiration against an upper airway obstruction. These negative pressures in the chest lead to increase venous supply to the right side of the heart (preload) while simultaneously creating more resistance for the left side of the heart to supply blood to the rest of the body (afterload). [4] This large negative force also results in a decrease of the forces exerted by fluids outside of the pulmonary blood vessels. This results in an increased amount of fluid shifting from these vessels into the lower pressure extravascular space. While there normally is a net passage of fluid out of the vasculature at baseline, this is a small enough amount to be drained from the extravascular space by the lymphatic system, and as such fluid does not accumulate. In the setting of NPPE, the excess shift of fluid overcome the ability of the lymphatic system, and fluid (edema) accumulates in the alveoli of the lungs. As these structures are important for gas exchange during respiration, patients with NPPE struggle to have adequate oxygen supply to the tissues of their body. [1] [4]

Causes

There are a variety of causes of NPPE, which can theoretically result from any upper airway obstruction. In adults, the most frequent cause is laryngospasm (involuntary contraction of the vocal cords) after extubation, making up approximately 50% of all adults cases of NPPE. The incidence of NPPE as a result of postextubation laryngospasm has been estimated to be between 0.1-3.0%. [1] [3] [5] In the pediatric setting, the reported most common causes of NPPE are both infectious in nature: croup and epiglottitis. [1] Other reported causes include endotracheal tube obstruction (e.g., from patient biting down on tube), tumors/masses compressing the upper airway, choking on foreign objects, strangulation. [1] [5] Interestingly, the use of sugammadex to reverse neuromuscular blockade (the mechanism of paralysis during surgery) has also been associated with increased incidence of NPPE [6]

Risk factors associated with development of NPPE include male sex, younger age, increased cardiovascular fitness, and undergoing head or neck surgery. [1] [2] [3]

Signs and symptoms

See signs and symptoms of pulmonary edema

Diagnosis

Diagnosis of NPPE is essentially a diagnosis of exclusion. When a patient presents with acute pulmonary edema in the perioperative setting, cardiac causes should first be excluded. This can be done with electrocardiogram, echocardiogram, measurement of cardiac enzymes, etc. Other causes of pulmonary edema that require rapid intervention and should be considered first include fluid overload, brain injury, and anaphylaxis. If when considering these differentials, there is no evidence for administration of excessive fluids, no focal signs suggesting a brain injury, and so signs of allergic reaction, one can then consider NPPE. Clinical signs supportive of upper airway obstruction such as stridor and/or wheezing in the setting of pulmonary edema point to the diagnosis of NPPE. [7]

Treatment

NPPE is potentially fatal, and prompt recognition is important to prevent adverse outcome. The first principle of treatment is to relieve the airway obstruction. Most commonly, this is done through endotracheal intubation. This ensures appropriate airway support and allows for easy supply of supplemental oxygen. Positive pressures oxygenation is used to reverse the negative pressures in the chest resulting from the obstruction. [2] [6] In cases where endotracheal intubation is difficult or cannot be done, creation of a surgical airway may be necessary in order provide positive-pressure ventilation. [1] If the cause of the obstruction is simply biting of the endotracheal tube, treatment can simply be administration of low dose succinylcholine in order prevent contraction of the jaw. [5]

Once the cause of obstruction and the resultant negative pressures are addresses, the rest of the management is the same as the standard care to relieve pulmonary edema.

Related Research Articles

<span class="mw-page-title-main">Tracheal intubation</span> Placement of a tube into the trachea

Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic tube into the trachea (windpipe) to maintain an open airway or to serve as a conduit through which to administer certain drugs. It is frequently performed in critically injured, ill, or anesthetized patients to facilitate ventilation of the lungs, including mechanical ventilation, and to prevent the possibility of asphyxiation or airway obstruction.

<span class="mw-page-title-main">Mechanical ventilation</span> Method to mechanically assist or replace spontaneous breathing

Mechanical ventilation, assisted ventilation or intermittent mandatory ventilation (IMV) is the medical term for using a machine called a ventilator to fully or partially provide artificial ventilation. Mechanical ventilation helps move air into and out of the lungs, with the main goal of helping the delivery of oxygen and removal of carbon dioxide. Mechanical ventilation is used for many reasons, including to protect the airway due to mechanical or neurologic cause, to ensure adequate oxygenation, or to remove excess carbon dioxide from the lungs. Various healthcare providers are involved with the use of mechanical ventilation and people who require ventilators are typically monitored in an intensive care unit.

<span class="mw-page-title-main">Croup</span> Respiratory infection often caused by a virus

Croup, also known as laryngotracheobronchitis, is a type of respiratory infection that is usually caused by a virus. The infection leads to swelling inside the trachea, which interferes with normal breathing and produces the classic symptoms of "barking/brassy" cough, inspiratory stridor and a hoarse voice. Fever and runny nose may also be present. These symptoms may be mild, moderate, or severe. Often it starts or is worse at night and normally lasts one to two days.

<span class="mw-page-title-main">Pulmonary edema</span> Fluid accumulation in the tissue and air spaces of the lungs

Pulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is due to either failure of the left ventricle of the heart to remove oxygenated blood adequately from the pulmonary circulation, or an injury to the lung tissue directly or blood vessels of the lung.

<span class="mw-page-title-main">Acute respiratory distress syndrome</span> Human disease

Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by rapid onset of widespread inflammation in the lungs. Symptoms include shortness of breath (dyspnea), rapid breathing (tachypnea), and bluish skin coloration (cyanosis). For those who survive, a decreased quality of life is common.

<span class="mw-page-title-main">Airway management</span> Medical procedure ensuring an unobstructed airway

Airway management includes a set of maneuvers and medical procedures performed to prevent and relieve airway obstruction. This ensures an open pathway for gas exchange between a patient's lungs and the atmosphere. This is accomplished by either clearing a previously obstructed airway; or by preventing airway obstruction in cases such as anaphylaxis, the obtunded patient, or medical sedation. Airway obstruction can be caused by the tongue, foreign objects, the tissues of the airway itself, and bodily fluids such as blood and gastric contents (aspiration).

<span class="mw-page-title-main">Respiratory arrest</span> Medical condition

Respiratory arrest is a serious medical condition caused by apnea or respiratory dysfunction severe enough that it will not sustain the body. Prolonged apnea refers to a patient who has stopped breathing for a long period of time. If the heart muscle contraction is intact, the condition is known as respiratory arrest. An abrupt stop of pulmonary gas exchange lasting for more than five minutes may permanently damage vital organs, especially the brain. Lack of oxygen to the brain causes loss of consciousness. Brain injury is likely if respiratory arrest goes untreated for more than three minutes, and death is almost certain if more than five minutes.

<span class="mw-page-title-main">Epiglottitis</span> Inflammation of the epiglottis

Epiglottitis is the inflammation of the epiglottis—the flap at the base of the tongue that prevents food entering the trachea (windpipe). Symptoms are usually rapid in onset and include trouble swallowing which can result in drooling, changes to the voice, fever, and an increased breathing rate. As the epiglottis is in the upper airway, swelling can interfere with breathing. People may lean forward in an effort to open the airway. As the condition worsens, stridor and bluish skin may occur.

<span class="mw-page-title-main">Superior vena cava syndrome</span> Group of symptoms caused by obstruction of the superior vena cava

Superior vena cava syndrome (SVCS), is a group of symptoms caused by obstruction of the superior vena cava ("SVC"), a short, wide vessel carrying circulating blood into the heart. The majority of cases are caused by malignant tumors within the mediastinum, most commonly lung cancer and non-Hodgkin's lymphoma, directly compressing or invading the SVC wall. Non-malignant causes are increasing in prevalence due to expanding use of intravascular devices, which can result in thrombosis. Other non-malignant causes include benign mediastinal tumors, aortic aneurysm, infections, and fibrosing mediastinitis.

Stridor is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the pharynx.

<span class="mw-page-title-main">Tracheitis</span> Inflammation of the trachea

Tracheitis is an inflammation of the trachea. Although the trachea is usually considered part of the lower respiratory tract, in ICD-10 tracheitis is classified under "acute upper respiratory infections".

<span class="mw-page-title-main">Ludwig's angina</span> Form of severe cellulitis of the mouth floor

Ludwig's angina is a type of severe cellulitis involving the floor of the mouth and is often caused by bacterial sources. Early in the infection, the floor of the mouth raises due to swelling, leading to difficulty swallowing saliva. As a result, patients may present with drooling and difficulty speaking. As the condition worsens, the airway may be compromised and hardening of the spaces on both sides of the tongue may develop. Overall, this condition has a rapid onset over a few hours.

<span class="mw-page-title-main">Respiratory disease</span> Disease of the respiratory system

Respiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, bronchioles, alveoli, pleurae, pleural cavity, the nerves and muscles of respiration. Respiratory diseases range from mild and self-limiting, such as the common cold, influenza, and pharyngitis to life-threatening diseases such as bacterial pneumonia, pulmonary embolism, tuberculosis, acute asthma, lung cancer, and severe acute respiratory syndromes, such as COVID-19. Respiratory diseases can be classified in many different ways, including by the organ or tissue involved, by the type and pattern of associated signs and symptoms, or by the cause of the disease.

Airway obstruction is a blockage of respiration in the airway that hinders the free flow of air. It can be broadly classified into being either in the upper airway (UPA) or lower airway (LOA).

<span class="mw-page-title-main">Alveolar lung disease</span> Medical condition

Alveolar lung diseases, are a group of diseases that mainly affect the alveoli of the lungs.

<span class="mw-page-title-main">Smoke inhalation</span> Medical condition

Smoke inhalation is the breathing in of harmful fumes through the respiratory tract. This can cause smoke inhalation injury which is damage to the respiratory tract caused by chemical and/or heat exposure, as well as possible systemic toxicity after smoke inhalation. Smoke inhalation can occur from fires of various sources such as residential, vehicle, and wildfires. Morbidity and mortality rates in fire victims with burns are increased in those with smoke inhalation injury. Victims of smoke inhalation injury can present with cough, difficulty breathing, low oxygen saturation, smoke debris and/or burns on the face. Smoke inhalation injury can affect the upper respiratory tract, usually due to heat exposure, or the lower respiratory tract, usually due to exposure to toxic fumes. Initial treatment includes taking the victim away from the fire and smoke, giving 100% oxygen at a high flow through a face mask, and checking the victim for injuries to the body. Treatment for smoke inhalation injury is largely supportive, with varying degrees of consensus on benefits of specific treatments.

<span class="mw-page-title-main">Pulmonary contusion</span> Internal bruise of the lungs

A pulmonary contusion, also known as lung contusion, is a bruise of the lung, caused by chest trauma. As a result of damage to capillaries, blood and other fluids accumulate in the lung tissue. The excess fluid interferes with gas exchange, potentially leading to inadequate oxygen levels (hypoxia). Unlike pulmonary laceration, another type of lung injury, pulmonary contusion does not involve a cut or tear of the lung tissue.

<span class="mw-page-title-main">Tracheobronchial injury</span> Damage to the tracheobronchial tree

Tracheobronchial injury is damage to the tracheobronchial tree. It can result from blunt or penetrating trauma to the neck or chest, inhalation of harmful fumes or smoke, or aspiration of liquids or objects.

Swimming induced pulmonary edema (SIPE), also known as immersion pulmonary edema, is a life threatening condition that occurs when fluids from the blood leak abnormally from the small vessels of the lung (pulmonary capillaries) into the airspaces (alveoli).

<span class="mw-page-title-main">Ventilation-perfusion coupling</span>

Ventilation-perfusion coupling is the relationship between ventilation and perfusion processes, which take place in the respiratory and cardiovascular systems. Ventilation is the movement of gas during breathing, and perfusion is the process of pulmonary blood circulation, which delivers oxygen to body tissues. Anatomically, the lung structure, alveolar organization, and alveolar capillaries contribute to the physiological mechanism of ventilation and perfusion. Ventilation-perfusion coupling maintains a constant ratio near 0.8 on average, while the regional variation exists within the lungs due to gravity. When the ratio gets above or below 0.8, it is considered abnormal ventilation-perfusion coupling, also known as a ventilation-perfusion mismatch. Lung diseases, cardiac shunts, and smoking can cause a ventilation-perfusion mismatch that results in significant symptoms and diseases, which can be treated through treatments like bronchodilators and oxygen therapy.

References

  1. 1 2 3 4 5 6 7 8 Bhattacharya, Mallar; Kallet, Richard H.; Ware, Lorraine B.; Matthay, Michael A. (2016-10-01). "Negative-Pressure Pulmonary Edema". Chest. 150 (4): 927–933. doi: 10.1016/j.chest.2016.03.043 . ISSN   0012-3692. PMID   27063348.
  2. 1 2 3 4 Udeshi, Ashish; Cantie, Shawn Michael; Pierre, Edgar (2010-09-01). "Postobstructive pulmonary edema". Journal of Critical Care. 25 (3): 538.e1–538.e5. doi:10.1016/j.jcrc.2009.12.014. ISSN   0883-9441. PMID   20413250.
  3. 1 2 3 Louis, Patrick J.; Fernandes, Rui (2002-01-01). "Negative pressure pulmonary edema". Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology. 93 (1): 4–6. doi:10.1067/moe.2002.119909. ISSN   1079-2104. PMID   11805770.
  4. 1 2 3 "Negative pressure pulmonary edema: Physiology". www.openanesthesia.org. Retrieved 2022-11-07.
  5. 1 2 3 Silva, Luisa Almeida Rodrigues; Guedes, Alexandre Almeida; Filho, Marcello Fonseca Salgado; Chaves, Leandro Fellet Miranda; Araújo, Fernando de Paiva (2019-03-01). "Negative pressure pulmonary edema: report of case series and review of the literature". Brazilian Journal of Anesthesiology (English Edition). 69 (2): 222–226. doi:10.1016/j.bjane.2018.12.002. ISSN   0104-0014. PMC   9391850 . PMID   30591273.
  6. 1 2 Liu, Ruizhu; Wang, Jian; Zhao, Guoqing; Su, Zhenbo (2019-04-26). "Negative pressure pulmonary edema after general anesthesia". Medicine. 98 (17): e15389. doi:10.1097/MD.0000000000015389. ISSN   0025-7974. PMC   6831334 . PMID   31027133.
  7. ↑ Krodel, David J.; Bittner, Edward A.; Abdulnour, Raja; Brown, Robert; Eikermann, Matthias; Riou, Bruno (2010-07-01). "Case Scenario: Acute Postoperative Negative Pressure Pulmonary Edema". Anesthesiology. 113 (1): 200–207. doi: 10.1097/ALN.0b013e3181e32e68 . ISSN   0003-3022. PMID   20526178. S2CID   10247621.
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