title: Pleural Fluid Analysis in Chronic Hemothorax: A Mimicker of Infection.
abstract: OBJECTIVE
  Timing to video-assisted thoracoscopic surgery (VATS) in hemothorax is based on preventing acute and long-term complications of retained blood products in the pleural space, including pleural space infection. We propose that the persistence of blood in the pleural space induces a proinflammatory state, independent of active infection.
  
  
  METHODS
  We identified six patients with a hemothorax by clinical history, radiographic imaging, and pleural fluid analysis from a database of 1133 patients undergoing thoracentesis from 2002 to 2010 at the Medical University of South Carolina.
  
  
  RESULTS
  In four of the six patients identified, the time from injury to thoracentesis was one, four, four, and five days, respectively. The fluid pH range was 7.32-7.41. The lactate dehydrogenase (LDH) range was 210-884 IU/L (mean 547 IU/L), and the absolute neutrophil count (ANC) range was 1196-3631 cells/µL. In two patients, the time from injury to thoracentesis was 7 and 60 days. In these two patients, the pH was 7.18 and 6.91, LDH was 1679 and 961 IU/L, and the ANC was 8134 and 5943 cells/µL. Microbiology and pathology were negative in all patients.
  
  
  CONCLUSIONS
  The persistence of blood outside the vascular compartment, and within the pleural space, biochemically mirrors infection. We will explore the multiple mechanisms that account for development of pleural fluid acidosis, inflammation, and neutrophil recruitment.
authors: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, SC, USA.
authors: Matthew L
authors: ML
authors: DiVietro
authors: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, SC, USA.
authors: John Terrill
authors: JT
authors: Huggins
authors: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, SC, USA.
authors: Lauren Brown
authors: LB
authors: Angotti
authors: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, SC, USA.
authors: Carlos E
authors: CE
authors: Kummerfeldt
authors: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Medical University of South Carolina, Charleston, SC, USA.
authors: Jennings E
authors: JE
authors: Nestor
authors: Associate Professor of Medicine, Division of Pulmonary and Critical Care Medicine, Albany Medical Center, Albany, NY, USA.
authors: Peter
authors: P
authors: Doelken
authors: Distinguished University Professor and Professor Emeritus, College of Medicine, Medical University of South Carolina, Charleston, SC, USA.
authors: Steven A
authors: SA
authors: Sahn
keywords: chronic; empyema; hemothorax; pleural effusion; pleural fluid analysis