Complicated pneumonia in ICU: Parapneumonic effusions, empyemas and lung abscesses

Abstract

Complicated respiratory infections involve the presence of a parapneumonic effusion, empyema, or pulmonary abscess. These complications are common and are responsible for significant morbidity and mortality. Although these nosological frameworks are subject to consensus, antibiotic duration, and source control methods remain subjects of debate.

Parapneumonic effusion, the most frequent complication, is characterized by exudative fluid in contact with pneumonia or a pulmonary abscess. Its bacteriological analysis is negative, and the biological data do not strongly suggest pleural infection. In such cases, drainage is optional, depending on the fluid volume and the patient's clinical tolerance. Pleural infection now includes complicated parapneumonic effusions (infection proven or highly probable based on biological criteria) and empyema. Both of these complications require drainage. Intrapleural fibrinolysis is indicated in cases where simple drainage and antibiotic therapy fail. Surgery can be considered in cases of persistent failure of initial medical management or earlier on in low-risk patients. Pulmonary abscesses, although rare in ICU, are associated with a hospital mortality rate of 25 to 35%. No study has demonstrated the superiority of an interventional strategy (through percutaneous or surgical drainage) over medical management alone.

This review presents the consensual management elements for these complex and polymorphic situations while addressing research opportunities on the still-debated therapeutic aspects. Without recommendations based on high-level evidence, early medico-surgical discussion is essential to optimize patient care.