Pleural Fluid Analysis in Chronic Hemothorax: A Mimicker of Infection.

OBJECTIVES: 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.

Improving the predictive accuracy of identifying exudative effusions.

BACKGROUND: Application of Light's criteria results in misclassification of some transudative effusions as exudative, particularly because of congestive heart failure (CHF). We sought to determine if the serum to pleural fluid albumin (SF-A) and serum to pleural fluid protein (SF-P) gradients increased the predictive accuracy to correctly identify exudative effusions. METHODS: We retrospectively analyzed 1,153 consecutive patients who underwent a diagnostic thoracentesis at the Medical University South Carolina. Univariable logistic regression analyses were used to determine the statistical significance of pleural fluid tests that correctly identified exudative effusions. Tests with significant diagnostic accuracy were combined in multivariable logistic regression models, with calculation of areas under the curve (AUCs) to determine their predictive accuracy. The predictive capability of the best model was compared with Light's criteria and other test combinations. RESULTS: Pleural fluid lactate dehydrogenase (LDH), SF-A gradient, and SF-P gradient had a significant effect on the probability of identifying exudative pleural effusions. When combined together in a multivariable logistic regression, LDH (OR, 14.09 [95% CI, 2.25-85.50]), SF-A gradient (OR, 7.16 [95% CI, 1.24-41.43]), and SF-P gradient (OR, 6.83 [95% CI, 1.56-27.88]) had an AUC of 0.92 (95% CI, 0.85-0.98). CONCLUSIONS: Application of Light's criteria, not uncommonly, misclassifies CHF transudative effusions as exudates. In cases where no cause for an exudative effusion can be identified or CHF is suspected, the sequential application of the fluid LDH, followed by the SF-P and then the SF-A gradients, may assist in reclassifying pleural effusions as transudates.

Warfarin-induced pulmonary metastatic calcification and calciphylaxis in a patient with end-stage renal disease.

Patients with end-stage renal disease (ESRD) receiving hemodialysis (HD) suffer from a number of metabolic derangements. Ectopic deposition of calcium in the skin, soft tissues, blood vessels, and viscera is a potentially devastating consequence of disorders of calcium and phosphorus homeostasis. We report the case of a patient with ESRD and secondary hyperparathyroidism receiving HD who developed metastatic pulmonary calcification and calciphylaxis following initiation of warfarin therapy after mechanical valve replacement. Because not all patients with ESRD receiving HD develop ectopic calcification, there appears to be a complex cascade of metabolic interactions that predispose patients to this process. Warfarin is a vitamin K antagonist with inhibitory effects not only on proteins of the coagulation cascade, but also on other important protein systems. Its role in ectopic calcium deposition has been the subject of theories and has been reported in the literature, but no link with metastatic pulmonary calcification has been made. Patients receiving HD have an increased incidence of conditions that require chronic anticoagulation with warfarin, such as VTE, atrial fibrillation, and valvular heart disease requiring valve replacement surgery. Bioprosthetic valves should be considered in these patients because of the potential risk of metastatic calcification when warfarin is used in the setting of mechanical valve replacement.

Statins decrease the occurrence of venous thromboembolism in patients with cancer.

BACKGROUND: Recent data suggest a reduction in the occurrence of venous thromboembolism in select groups of patients who use statins. The objective of this study is to evaluate the impact of statin use on the occurrence of venous thromboembolism in patients with solid organ tumor. METHODS: We conducted a retrospective, case-control study reviewing 740 consecutive patients with a diagnosis of solid organ tumor who were admitted to the Albert Einstein Medical Center, Philadelphia, Penn, between October 2004 and September 2007. Patients treated with anticoagulation therapy before their first admission were excluded. The occurrence of venous thromboembolism, risk factors for venous thromboembolism, and statin use were recorded. Patients who never used statins or had used them for less than 2 months were relegated to the control group. RESULTS: The mean age of the study population was 65 years, and 52% of the patients were women and 76% were African American. The occurrence of venous thromboembolism was 18% (N=132), and 26% (N=194) were receiving statins. Among patients receiving statins, 8% (N=16) developed a venous thromboembolism compared with 21% (N=116) in the control group (odds ratio 0.33; 95% confidence interval, 0.19-0.57). A logistic regression analysis including risk factors for venous thromboembolism (metastatic disease, use of chemotherapy, immobilization, smoking, and aspirin use) along with statin use yielded the same results. CONCLUSION: This study suggests that the use of statins is associated with a significant reduction in the occurrence of venous thromboembolism. This pleiotropic effect warrants further investigation.