Imaging characteristics and mechanism of negative pressure pulmonary edema in children: three case reports

This article reports three children who presented with negative pressure pulmonary oedema before or after removal of the airway foreign bodies. Of them, two cases were type I negative pressure pulmonary oedema and one case was type II negative pressure pulmonary oedema following foreign body removal from the airways. Pathogenesis and location differences between type I and type II negative pressure pulmonary oedema caused by airway foreign body obstruction, as well as diagnosis and treatment modalities of the negative pressure pulmonary oedema were discussed.

Kerosene Oil Pneumonitis

Radiographic abnormalities in the lungs are very common in an individual positive for HIV antibodies. Majority of lesions are of infective or neoplastic in origin. We present a case of chemical pneumonitis following regurgitation of kerosene oil in a patient positive for human immunodeficiency virus (HIV) antibodies. Chemical pneumonitis is diagnosed with a characteristic clinical history of regurgitation of fluid and gravity-dependent infiltration in the lung on chest x-ray. Another condition arising from the aspiration of the fluid/chemical is negative-pressure pulmonary oedema which results from laryngeal spasm following regurgitation of fluid. Chest radiography, however, distinguishes it from chemical pneumonitis. Bilateral infiltration is seen in the former, while lesion at dependent portion of right lung is seen in the latter condition.

Choking as a cause of negative pressure pulmonary oedema (NPPE) in an older adult

An 86-year-old female presented to the Emergency Department (ED) in respiratory distress after choking on a sandwich at home. Her family had noticed that she had had difficulty during and coughing after swallowing for several months. Her initial chest x-ray showed diffuse alveolar infiltrates in both lungs and blood tests showed normal white cells and C-Reactive Protein (CRP). She was started on intravenous antibiotics for presumed aspiration pneumonia and received 15 L of oxygen. However, the infiltration had dramatically improved, both radiologically and clinically, within 24 hours. She was diagnosed with negative pressure pulmonary oedema (NPPE) type 1 and made a rapid recovery. The Speech and Language Team diagnosed an impaired swallow and advised soft or bite-sized suitable foods. We discussed the ongoing risk of aspiration and long-term feeding options with the patient’s family. We agreed on a conservative plan for ‘risk feeding’, given her frailty and co-morbidities, and began discussions on ceilings of care. This case aims to raise awareness of NPPE so that it can be diagnosed, investigated and treated promptly. Although seen most commonly by intensivists and anaesthetists, it is relevant to those on the acute medical take and geriatricians managing patients with swallowing difficulties.

Near-fatal negative pressure pulmonary oedema successfully treated with venovenous extracorporeal membrane oxygenation performed in the hybrid emergency room

We report a rare case of negative pressure pulmonary oedema (NPPE), a life-threatening complication of tracheal intubation. A 41-year-old obese man was admitted to a previous hospital for neck surgery. After extubation, he developed respiratory distress followed by haemoptysis and desaturation. The patient was reintubated and brought to our hospital where we introduced venovenous extracorporeal membrane oxygenation (ECMO) to prevent cardiac arrest, which is an unusual clinical course for NPPE. He returned to his routine without any sequelae. This is the first case report of NPPE successfully resolved with venovenous ECMO in the hybrid emergency room (hybrid ER), which is a resuscitation room equipped with interventional radiology features and a sliding CT scanner. Since the hybrid ER serves as a single move for patients where all necessary procedures are performed, it has the potential to lower the incidence of cannulation complications, beyond the delay in ECMO initiation.

Postobstructive negative pressure pulmonary oedema in a dog

A 4-month-old English bulldog was anaesthetised for investigation and management of chronic urinary incontinence. In the postanaesthetic period, the patient developed respiratory distress, with marked cough and increased inspiratory effort. Diagnostic imaging suggested pulmonary oedema. After excluding all other causes of cardiogenic and non-cardiogenic pulmonary oedema, it was hypothesised that the patient developed postanaesthetic negative pressure pulmonary oedema, suspected to have been exacerbated by tracheal intubation with an oversized endotracheal tube leading to laryngeal swelling and obstruction. The animal was treated with oxygen supplementation, corticosteroids and β-2 adrenergic receptor agonists. The patient recovered from the event and was discharged from the hospital after 48 hours. This article discusses in further details other management options of negative pressure pulmonary oedema. This is the first case report discussing the pathophysiology, critical care and management of postanaesthetic negative pressure pulmonary oedema in a dog.