Negative pressure pulmonary edema revisited: Pathophysiology and review of management

Abstract

Negative pressure pulmonary edema (NPPE) is a dangerous and potentially fatal condition with a multifactorial pathogenesis. Frequently, NPPE is a manifestation of upper airway obstruction, the large negative intrathoracic pressure generated by forced inspiration against an obstructed airway is thought to be the principal mechanism involved. This negative pressure leads to an increase in pulmonary vascular volume and pulmonary capillary transmural pressure, creating a risk of disruption of the alveolar-capillary membrane. The early detection of the signs of this syndrome is vital to the treatment and to patient outcome. The purpose of this review is to highlight the available literature on NPPE, while probing the pathophysiological mechanisms relevant in both the development of this condition and that involved in its resolution.

Keywords: Airway obstruction; negative pressure; negative pressure pulmonary edema; postoperative.

Figure 1

Postulated mechanisms of pulmonary edema secondary to upper airway obstruction

Figure 2

Chest radiograph of a patient who presented to intensive care department after a postoperative negative pressure pulmonary edema showing diffuse interstitial and alveolar infiltrates

Figure 3

Flow chart showing a methord for diagnosing negative pressure pulmonary edema (NPPE)