The incidence of pleural effusion in COVID-19 pneumonia: State-of-the-art review.
Woon H Chong, Biplab K Saha, Edward Conuel and 1 others
PMID 33831700WHAT IT FOUND
Pleural effusion was reported in 7.3% of hospitalized COVID-19 patients across 47 observational studies.
It was usually unilateral, appeared later in illness, and was more frequent in critically ill or MIS patients, but causes and outcomes remain unclear.
Key findings
01In 47 observational studies of 4981 COVID-19 patients, pleural effusion was reported in 7.3% (365/4981).
02Pleural effusion was more frequent in critically ill patients than non-critically ill patients, including 18% versus 3.1% (p < 0.001) in one study and 33-43% versus 3-13% (p < 0.05) across several studies.
03Pleural effusions were usually detected 5-7 days after admission and at least 11 days after symptom onset, and serial imaging showed incidence rising during the hospital course.
STILL TO COME
How it was doneWhat they foundWhat it means for RNs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The included studies were heterogeneous, and pleural effusion was often a secondary or incidental finding rather than a primary outcome. No study compared patients who developed pleural effusion with those who did not, so risk factors and outcomes could not be analyzed. Many patients had comorbidities, possible co-infections, or fluid overload that were not fully excluded, so the review cannot show that SARS-CoV-2 directly caused the effusions. The search was limited to English articles, and 25 non-English studies were excluded. Most diagnoses relied on CT chest, and limited imaging during the pandemic may have missed effusions. Pleural fluid characteristics came from only 4 case reports/series involving 7 patients, because no drainage was performed in the 47 observational studies. High mortality may have competed with later effusion development and underestimated risk in survivors. The authors state there is a lack of quality evidence for length of stay, ventilation, risk factors, management, and prognosis.
Declared interests
The authors declared no competing interests.
The easy way to misread this
Do not read pleural effusion as a direct complication of SARS-CoV-2 or as a proven cause of worse outcomes. The review found no study comparing patients with and without effusion, many had other causes or comorbidities, and pleural fluid data came from only 7 patients.