Non-cardiogenic pulmonary oedema due to foreign body aspiration

Noncardiogenic pulmonary edema in small animals

OBJECTIVE

To review various types of noncardiogenic pulmonary edema (NCPE) in cats and dogs.

ETIOLOGY

NCPE is an abnormal fluid accumulation in the lung interstitium or alveoli that is not caused by cardiogenic causes or fluid overload. It can be due to changes in vascular permeability, hydrostatic pressure in the pulmonary vasculature, or a combination thereof. Possible causes include inflammatory states within the lung or in remote tissues (acute respiratory distress syndrome [ARDS]), airway obstruction (post-obstructive pulmonary edema), neurologic disease such as head trauma or seizures (neurogenic pulmonary edema), electrocution, after re-expansion of a collapsed lung or after drowning.

DIAGNOSIS

Diagnosis of NCPE is generally based on history, physical examination, and diagnostic imaging. Radiographic findings suggestive of NCPE are interstitial to alveolar pulmonary opacities in the absence of signs of left-sided congestive heart failure or fluid overload such as cardiomegaly or congested pulmonary veins. Computed tomography and edema fluid analysis may aid in the diagnosis, while some forms of NCPE require additional findings to reach a diagnosis.

THERAPY

The goal of therapy for all types of NCPE is to preserve tissue oxygenation and reduce the work of breathing. This may be achieved by removing the inciting cause (eg, airway obstruction) and cage rest in mild cases and supplemental oxygen in moderate cases and may require mechanical ventilation in severe cases.

PROGNOSIS

Prognosis is generally good for most causes of veterinary NCPE except for ARDS, although data are scarce for some etiologies of NCPE.

Post-obstructive pulmonary edema from aspirated nuts

OBJECTIVES

Post-obstructive pulmonary edema is thought to occur from hemodynamic changes secondary to forced inspiration against the closed airway due to acute or chronic airway obstruction. We report a case of a 13 month-old boy who developed pulmonary edema from aspirated foreign body, nuts.

METHODS

He underwent emergency bronchoscopy to confirm the clinical diagnosis of aspirated nuts in the trachea and nuts were removed endoscopically. His trachea was then intubated and he was mechanically ventilated with oxygen.

RESULTS

He developed florid pulmonary edema early in the course with tracheal obstruction and during endoscopic removal of nuts. After removal of obstruction he was ventilated mechanically and pulmonary edema cleared rapidly.

CONCLUSIONS

Aspirated nuts obstructing trachea can induce obstructive pulmonary edema. Early recognition of foreign body obstruction based on clinical history and its removal resolved pulmonary edema.

Postobstructive pulmonary edema in children

Children with either acute or chronic upper airway obstruction are at risk for postobstructive pulmonary edema. Appropriate diagnosis and management are important in leading to a good outcome for the patient. We describe 2 cases of postobstructive pulmonary edema caused by brief acute upper airway obstruction. In the first case, a child choked on a hot dog and in the second on a "jawbreaker." Both children developed symptoms of complete upper airway obstruction and were managed initially with the Heimlich maneuver and subsequently developed increased work of breathing associated with an oxygen requirement after relief of the obstruction. Both children were managed in the pediatric intensive care unit and were discharged after resolution of symptoms without sequelae.