Pleural Fluid Total Protein Research Articles

ROLE OF COMBINED PLEURAL FLUID CHOLESTEROL AND TOTAL PROTEIN FOR DIFFERENTIATING EXUDATIVE FROM TRANSUDATIVE PLEURAL EFFUSION IN A TERTIARY CARE CENTRE-AN OBSERVATIONAL STUDY

Introduction:Identifying whether the pleural effusion is exudative or transudative is the first step in making a diagnosis.Lights criteria, have been accepted more widely than any other criteria for discriminating between transudative and exudative effusions.But incorrectly labels 15–20% of transudative effusions as exudates. We investigate if comparable results may be obtained using pleural fluid cholesterol and pleural fluid total protein. Objectives:To compare combined pleural fluid cholesterol and pleural fluid total protein with Light’s criteria in differentiating exudative and transudative effusion and find its significance. Methods:This is a hospital based cross sectional study conducted in the Department of Respiratory medicine, GMC, Kannur over a period of one year on 120 patients who presented with pleural effusion,and fulfilling the inclusion and exclusion criteria. The pleural fluid sample obtained from each patient was taken for analysis,and nature of effusion by using Light’s criteria and combined pleural fluid cholesterol+total protein was noted. The final diagnosis based on clinical diagnosis along with HPR and/or culture was set as the gold standard. Mc Nemar’s Chi-square test was applied to compare Light’s criteria and Pleural fluid cholesterol+total protein with gold standard.The diagnostic parameters like sensitivity, specificity, PVP, PVN and accuracy of Light’s criteria and pleural fluid cholesterol+ total protein to predict exudates were estimated. Results: We found out that there is significant difference in the classification of transudate and exudate by Light’s criteria with respect to gold standard (p-value 0.001). Kappa value 0.722 shows a significant substantial agreement between Light’s criteria and gold standard test (p-value <0.001). The sensitivity ,specificity, PVP,PVN and accuracy of Light’s criteria to predict exudate was 100.00%,63.33%, 89.11%,100.00%, and 90.83% respectively. Also, there is significant difference in the classification of transudate and exudate by Pleural fluid cholesterol+total protein with respect to gold standard (p-value 0.031). Kappa value 0.875 shows a significantly almost perfect agreement between pleural fluid Cholesterol+Total protein and gold standard test (p-value <0.001).The sensitivity, specificity, PVP,PVN and accuracy of Pleural fluid Cholesterol+Total protein to predict exudate was 93.33%, 100.00%, 100.00%,83.33%, and 95.00% respectively. Conclusion: As compared to Light’s criteria, Pleural fluid cholesterol+total protein shows a high agreement with gold standard to distinguish exudative and transudative effusion and can be used as an alternative to Light’s criteria.

Combined Pleural Fluid Cholesterol and Total Protein in Differentiation of Exudates and Transudates

The management strategy to be adopted in pleural effusion depends on whether an effusion is a transudate or exudate. To evaluate the usefulness of pleural fluid cholesterol and/or total protein measurements for differentiating between exudates and transudates, and to compare it with Light's criteria. In this prospective study 60 patients with pleural effusion were included. Pleural fluid total protein, lactate dehydrogenase (LDH) and cholesterol as well as serum total protein and LDH levels along with other investigations were studied. Clinical classification of transudate or exudate was done on the basis of aetiology. Based on clinical signs and symptoms, chest radiograph, other investigations and response to treatment, 49 of these effusions were classified as exudates and 11 as transudates. Using pleural fluid cholesterol levels at a cut-off point of greater than 60 mg/dL and/or total protein at a cut-off point of greater than 3 g/dL for distinguishing transudates and exudates, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), were 100 percent. Using Light's criteria for discriminating transudates and exudates, sensitivity, specificity, PPV and NPV were found to be 98%; 100%; 100% and 92%, respectively. The differences resulted from a mis-classification of one expected exudate as transudate by Light's criteria. Pleural fluid cholesterol and total protein are simple, cost-effective, and useful parameters in distinguishing pleural transudates from exudates, with the advantage of requiring only two laboratory determinations and no simultaneous blood sample, compared to the use of Light's criteria.

Role of Combined Pleural Fluid Cholesterol and Total Protein in Differentiation of Exudates and Transudates

Introduction: Light's criteria had been the standard method for distinguishing exudative and transudative pleural effusions which misidentify 15-20% of transudates as exudates. This study aims to find out the role of combined pleural fluid cholesterol and total protein in distinguishing exudative from transudative pleural effusions and its applicability in Nepalese populations.
 Materials and Methods: Patients with pleural effusions were enrolled for the study. The combined pleural fluid cholesterol and total protein were compared with Light’s criteria and also compared with the diagnosis on discharge to find out their usefulness in categorizing the pleural effusions.
 Results: A total of 81 patients enrolled in the study, 42 (51.9%) were male. Based on Light’s criteria, 88.8% pleural effusions were found to be exudates and 11.1% were found to be transudates. Within the criteria, Light’s criteria categorized more pleural fluids as exudates than the diagnosis on discharge. Based on pleural fluid cholesterol >60mg/dL and protein >3g/dL for the classification of exudative and transudative pleural fluid, 62.9% out of 81 samples felled under the exudates and 37.03% pleural effusions under transudates with the sensitivity 87.9% and specificity 100%.
 Conclusions: Though Light’s criteria remain the gold standard to differentiate transudates and exudates, combined pleural fluid cholesterol and total protein give nearly comparable results without the need for simultaneous blood investigations.

PLEURAL FLUID TO SERUM BILIRUBIN RATIO IN DIFFERENTIATION OF TRANSUDATE AND EXUDATE

SESSION TITLE: Tuesday Abstract Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/22/2019 01:00 PM - 02:00 PM PURPOSE: To evaluate the utility of pleural fluid to serum bilirubin ratio for differentiating between exudate and transudate METHODS: In this prospective study 60 patients with pleural effusion were included. Pleural fluid total protein, lactate dehydrogenase (LDH) and bilirubin as well as serum total protein, LDH and bilirubin levels along with other investigations were studied. Clinical classification of the effusion into exudate or transudate was done on the basis of aetiology. RESULTS: Based on clinical signs and symptoms, chest radiograph, other investigations and treatment response, 48 of these effusions were identified as exudate and remaining 12 as transudate. Pleural fluid to serum bilirubin ratio at cut off 0.4 mg/dl for distinguishing between exudates and transudates, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 93.75%, 58.33%, 90% and 70% respectively CONCLUSIONS: Though Light’s criteria is considered as gold-standard for differentiating between exudate and transudate in pleural effusion, it takes into account the LDH levels which might not be feasible at times due lack of facility at peripheral level particularly in developing countries. The pleural fluid to serum bilirubin ratio can serve as an alternative diagnostic tool in differentiating between exudates and transudates. CLINICAL IMPLICATIONS: The pleural fluid to serum bilirubin ratio can serve as an alternative easy and cost-effective diagnostic tool which help in determining the type of effusion aiding in further management of the disease. DISCLOSURES: No relevant relationships by ISHA GARASIA, source=Web Response No relevant relationships by Anand Patel, source=Web Response

“Efficacy of Total Pleural Fluid Bilirubin And Ratio to Serum Levels, Pleural Fluid Cholesterol And Total Protein Level in Diagnosing Pleural Effusion Exudates And Transudates And Its Correlation with light’s Criteria”

INTRODUCTION: Pleural effusion is a very common clinical presentation of diseases. A correct diagnosis of the underlying disease is essential for the management of pleural effusion. Therefore, the first step is to classify them as transudates or exudates. Light’s criteria is the most commonly used method. It was found that even Light’s criteria misclassified a large number of effusions, 25% of transudates as exudates. Hence, there is a need to investigate into new parameters which will prove to be superior or supportive to the present available array of tests. Hence, this study is being done to evaluate the Efficacy of Total Pleural fluid Bilirubin and its ratio to serum Bilirubin levels, Pleural fluid Cholesterol and Pleural fluid total Protein level in classifying the Pleural Effusion as Exudates and Transudates and its correlation with Light’s criteria. AIMS AND OBJECTIVES: To evaluate the usefulness of Total Pleural fluid Bilirubin and its ratio to serum Bilirubin levels, Pleural fluid Cholesterol and Pleural fluid Total Protein level in classifying pleural effusions as exudates and transudates. MATERIALS AND METHODS: STUDY POPULATION: This study is to be conducted among 50 patients with pleural Effusion, attending the Department of Medicine & Department of Thoracic Medicine in Govt. Rajaji Hospital, Madurai STUDY PROTOCOL: 1. Patients with clinical and radiological evidence of pleural effusion are to be included in the study.Then they are classified in to exudates and transudates on the basis of the clinical, radiological and biochemical evaluation. 2. Pleural fluid bilirubin & Serum Bilirubin, Pleural fluid cholesterol, Pleural fluid total protein are estimated and the patients are classified in to exudates and transudates. Then the patients are classified in to exudates and transudates on the basis of Light’s criteria. 3. Now the classification of exudates and transudates done on the basis of Total Pleural fluid bilirubin and its ratio to serum bilirubin, Pleural fluid cholesterol, Pleural fluid Total protein are compared with results of the classification of exudates and transudates done on the basis of Light’s criteria. 4. Sensitivity, specificity, Positive predictive value, negative predictive value, diagnostic accuracy of each testsare calculated. RESULTS: From our study we came to known that there was no statistically significant difference among various criterias in classifying pleural effusion as exudates and transudates. The misclassification of exudates and transudates by various criteria when compared to Light’s criteria is not statistically significant as p value is <0.05. CONCLUSION: From our study we came to a conclusion that to classify an exudative pleural effusion from a transudative pleural effusion - most specific test is pleural fluid total protein and - most sensitive test is pleural fluid / serum bilirubin ratio. The positive predictive value, negative predictive value and diagnostic accuracy is higher for pleural fluid total protein. To conclude, though Light's criteria remains as gold standard to differentiate transudates and exudates, in cases where there is a mismatch between clinical diagnosis and the outcome from Light's criteria, pleural fluid bilirubin / serum bilirubin ratio and pleural fluid total protein evaluation may add to the diagnostic accuracy.

Significance of Total Protein, Albumin, Globulin, Serum Effusion Albumin Gradient and LDH in the Differential Diagnosis of Pleural Effusion Secondary to Tuberculosis and Cancer

Lung cancer and Pulmonary tuberculosis are two major public health problems associated with significant morbidity and mortality worldwide particularly in low and middle income countries like India. Wrong diagnosis of lung cancer cases as pulmonary tuberculosis in primary health care system delays the onset of anti-cancer chemotherapy as well as initiation of DOTS thus increasing complication and mortality rate in malignancy patients. In this context easy, cost effective diagnostic tool at primary level must be the priority and need of hour. To study and evaluate any significance of biochemical parameters (total protein, albumin, globulin, serum effusion albumin gradient, LDH) in serum and pleural effusion secondary to tuberculosis and lung cancer. A case control study was carried out on patients attending OPD and IPD, Department of Pulmonary Medicine, RMCH. Hundred cases of Tuberculosis effusion, 50 cases of Malignant effusion and 100 age and sex matched apparently healthy controls were taken for correlation of biochemical parameters (total protein, albumin, globulin, serum effusion albumin gradient, LDH) and statistically evaluated to find any significance between tuberculosis, lung cancer and control group. Blood and pleural fluid samples were collected and then subjected to assessment of parameters (total protein, albumin, LDH) by using EM360 Autoanalyser and kits were supplied by Transasia diagnostics. Globulin and Serum Effusion Albumin Gradient (SEAG) was calculated mathematically. Data is presented as mean ± SD. Comparison of serum and pleural fluid levels (of taken parameters) were done in TB, Lung Cancer and Control groups by ANOVA and students t-test. The p-value <0.05 were considered as statistically significant. We found serum-total protein, albumin, globulin to be significantly higher in TB group than lung cancer group but serum LDH was higher in lung cancer group (in all parameters p=<0.0001). Pleural Fluid-total protein, albumin, globulin was again significantly higher in TB group than lung cancer group and LDH was higher in lung cancer group (p=<0.0001). SEAG is also significantly higher in TB group than lung cancer group (p=<0.002). The results suggests early quantization of these parameters can differentiate pulmonary tuberculosis from lung cancer and thus can decrease the mortality rate of lung cancer cases though more extensive study with increased sample size may provide more insights.

Can diffusion weighted MRI differentiate between inflammatory-infectious and malignant pleural effusions?

To assess exudative pleural effusions with diffusion-weighted magnetic resonance imaging (DW-MRI) in order to determine non-invasive differentiation criteria for inflammatory-infectious and malignant effusions. Thirty-two patients with pleural effusions underwent DW-MRI with 4 different b values (10, 500, 750 and 1000 s/mm2). ADC maps were generated automatically. Signal intensity and ADC values were measured. Following MRI, pleural fluid of 10-15 ml was obtained and analyzed. AUC values were compared for different diffusion levels of ADC and SI measurements. The relationship between ADC values and pleural effusion LDH and total protein levels was examined. The cut-off values obtained from signal intensity and ADC measurements to differentiate exudates with malignant pathology were not found to be statistically significant. In the inflammatory-infectious group, a significant negative correlation was observed between ADC values and pleural fluid LDH measurements in all b values. In the malignant group, a significant positive correlation was observed between ADC values and pleural fluid total protein measurements in b values of 500 and 1000. Infectious/inflammatory and malignant effusions overlap strongly and cannot therefore be differentiated using DW MRI.

Pleural Fluid Analysis and Radiographic, Sonographic, and Echocardiographic Characteristics of Hepatic Hydrothorax

There are limited published data defining complete pleural fluid analysis, echocardiographic characteristics, or the presence or absence of ascites on sonographic or CT imaging in patients with hepatic hydrothorax. We reviewed pleural fluid analysis and radiographic, sonographic, and echocardiographic findings in 41 consecutive patients with hepatic hydrothorax referred to the Pleural Procedure Service for thoracentesis. Ascites was detected on sonographic or CT imaging in 38 of 39 patients (97%). Diastolic dysfunction was found in 11 of 21 patients (52%). Contrast echocardiography with agitated saline demonstrated an intrapulmonary shunt in 18 of 23 cases (78%). Solitary hepatic hydrothorax had a median pleural fluid pH of 7.49 (fifth to 95th percentile, 7.40-7.57), total protein level of 1.5 g/dL (0.58-2.34), and lactate dehydrogenase (LDH) level of 65 IU/L (36-138). The median pleural fluid/serum protein ratio and pleural LDH/upper limit of normal serum LDH ratio were 0.25 (0.10-0.43) and 0.27 (0.14-0.57), respectively. The median absolute neutrophil count (ANC) was 26 cells/μL (1-230). Only a single patient had a protein discordant exudate despite 83% of patients receiving diuretics. When comparing solitary hepatic hydrothorax and spontaneous bacterial pleuritis, there was no statistically significant difference among pleural fluid total protein (P = .99), LDH (P = .33), and serum albumin (P = .47). ANC was higher in patients with spontaneous bacterial pleuritis (P < .0001). Hepatic hydrothorax virtually always presents with ascites that is detectable on sonographic or CT imaging. The development of an "exudate" from diuretic therapy is a rare phenomenon in hepatic hydrothorax. In contrast, diastolic dysfunction and intrapulmonary shunting are common in patients with hepatic hydrothorax. There was no statistically significant change in pleural fluid parameters with spontaneous bacterial pleuritis, except an increased ANC.

A new approach to pleural effusion in cats: Markers for distinguishing transudates from exudates

Classification of pleural effusion (PE) is central to diagnosis. Traditional veterinary classification has distinguished between transudates, modified transudates and exudates. In human medicine PEs are divided into only two categories: transudates and exudates. The aim of this study was to evaluate, in 20 cats presented with PE, paired samples of serum and pleural fluid for the following parameters: Light's criteria (pleural fluid lactate dehydrogenase concentration (LDHp), pleural fluid/serum LDH ratio, pleural fluid/serum total protein ratio (TPr)), pleural fluid total protein, pleural fluid cholesterol concentration, pleural fluid/serum cholesterol ratio (CHOLr), serum-effusion cholesterol gradient (serum cholesterol minus PE cholesterol concentration (CHOLg)), PE total nucleated cells count (TNCCp) and pleural fluid glucose (GLUp). LDHp and TPr were found most reliable when distinguishing between transudates and exudates, with sensitivity of 100% and 91% and specificity of 100%, respectively. When conflict between the clinical picture and laboratory results exists, calculation of CHOLr, CHOLg and TNCCp measurement may help in the classification of the effusion. Measurement of serum albumin (in the case of a transudate) may provide additional information regarding the pathogenesis of the effusion.

Pleural fluid findings as prognostic factors for malignant pleural mesothelioma

The aim of this study was to determine the prognostic value of pleural fluid glucose, lactate dehydrogenase (LDH), albumin, total protein, and total leukocyte levels in patients with malignant pleural mesothelioma. We retrospectively analyzed 71 consecutive patients (33 men and 38 women) who were referred to the department of chest diseases in a university hospital. Pleural fluid glucose levels, the ratio of pleural fluid to serum LDH>1.0, and total leukocyte count were significant predictors for the survival in univariate analysis. However, none of these variables emerged as statistically significant from the multivariate Cox model. In conclusion, our results showed that there is an inverse correlation between the intensity of inflammation and survival.

Characteristics of Trapped Lung: Pleural Fluid Analysis, Manometry, and Air-Contrast Chest CT

Study objectives:To review the pleural fluid characteristics, pleural manometry, and radiographic data of patients who received a diagnosis of trapped lung in our pleural diseases service.Design:Retrospective case series.Methods:The procedure records of 247 consecutive patients who underwent pleural manometry at the Medical University of South Carolina between October 2002 and November 2005 were reviewed. Eleven patients in whom a diagnostic pneumothorax was introduced were identified. Manometry data, radiographic findings, pleural fluid analysis, final clinical diagnosis, and information regarding the initial pleural insult were retrieved from the medical record.Results:All 11 patients had a clinical diagnosis of trapped lung. The causes of trapped lung were attributed to coronary artery bypass graft surgery, uremia, thoracic radiation, pericardiotomy, spontaneous bacterial pleuritis and repeated thoracentesis, and complicated parapneumonic effusion. Mean pleural fluid pH was 7.30, pleural fluid lactate dehydrogenase (LDH) was 124 IU/L, and pleural fluid total protein was 2.9 g/dL. Pleural fluid was paucicellular with mononuclear cell predominance. Pleural space elastance was increased in all cases and ranged from 19 to 149 cm H2O/L of pleural fluid removed. All demonstrated abnormal visceral pleural thickness on air-contrast chest CT.Conclusions:Trapped lung is a clinical entity characterized by the presence of a restrictive visceral pleural peel that was first described in 1967. The pleural fluid is paucicellular, LDH is low, and protein may be in the exudative range. The elevated total pleural fluid protein may be related to factors other than active pleural inflammation or malignancy and does not exclude the diagnosis.

Pleural Effusions in a Series of 181 Outpatients With Sarcoidosis

Pleural effusion (PE) is considered to be a rare manifestation of pulmonary sarcoidosis. We performed thoracic ultrasonography prospectively in consecutive outpatients with sarcoidosis to determine the frequency of PEs caused by sarcoidosis and to define their pleural fluid characteristics. Consecutive outpatients aged >/= 18 years with biopsy-proven sarcoidosis underwent ultrasonography. University hospital, outpatient sarcoidosis clinic. One hundred eighty-one outpatients were enrolled into the study. The subjects were predominately African-American and female. Most were between 30 and 60 years of age. The Scadding radiograph stages were fairly evenly distributed across all five stages (0 through 4). Five (2.8%) of 181 patients were found to have pleural fluid. Two patients had a unilateral left-sided PE, and three patients had bilateral PEs. Pleural fluid analysis (PFA) was performed in four patients. The PFA showed a lymphocyte-predominant exudate using protein criterion in only two patients, which is consistent with sarcoidosis-related PE; one patient underwent pleural biopsy, which was consistent with the diagnosis of sarcoidosis. A sarcoidosis-related PE was seen in 1 of 9 patients (11.1%) who had an exacerbation of pulmonary sarcoidosis compared to 1 of 172 patients (0.6%) who did not have an exacerbation (p < 0.4). PEs are rare in outpatients with sarcoidosis, even when a sensitive technique, such as ultrasonography, is used. The frequency of PEs was 2.8% (5 of 181 patients) with only 2 of the 181 PEs (1.1%) caused by sarcoid pleural involvement. PE in patients with sarcoidosis should not be assumed to be related to sarcoidosis. Discordance between levels of pleural fluid total protein and lactate dehydrogenase may be a characteristic finding in patients with sarcoid PE. An exacerbation of pulmonary sarcoidosis was not an independent risk factor for the development of sarcoid-related PE.

The relation of the pleural thickening in tuberculosis pleurisy with the activity of adenosine deaminase

Residual pleural thickening (RPT) still occurs in most patients with tuberculosis pleurisy despite advances in the treatment of tuberculosis. The aim of this study was to evaluate the significance of RPT in tuberculosis pleurisy with the patients clinical findings, biochemical and microbiological properties of pleural effusion and with the total adenosine deaminase (ADA) and isoenzymes levels. 121 tuberculosis pleurisy patients were evaluated retrospectively. According to posteroanterior chest x-rays, the 63 (52%) cases with the thickness 2 mm or more in lower lateral hemithorax were grouped as I and the 58 (48%) cases without pleural thickness were grouped as II. The amount of pleural effusion was classified into small, medium or massive according to their chest x-rays. In both groups; sex, age, symptoms score, bacteriological and biochemical tests and ADA levels were recorded. 81 (67%) male and 40 (33%) female, overall 121 patients were enrolled into the study. RPT was found higher in males (p=0.014) and the increase ran parallel with the amount of cigarette smoking (p=0.014). RPT was found to be lower in small effusions (p=0.001). The group with RPT, the serum albumin was found lower (p=0.002), pleural fluid total protein (p=0.047) and the ratio of pleural fluid protein to serum protein (p=0.002) were found higher. In group I, total ADA: 69.5 +/- 38.9 IU/L and ADA2: 41.3 +/- 31.6 IU/L were higher than the cases without RPT (p=0.032, p=0.017, respectively). We suggest that the immunological mechanisms are effective in the development of pleural thickening.

Low complement levels and opsonic activity in hepatic hydrothorax: its relationship with spontaneous bacterial empyema.

To analyze the pleural fluid factors that might cause spontaneous bacterial empyema (SBEM) in patients with cirrhotic hydrothorax. Pathogenic mechanism of SBEM of cirrhotic patients is probably similar to that of spontaneous bacterial peritonitis, but local factors affecting pleural fluid have not been studied. Determination of C3, C4, and opsonic activity levels of pleural fluid in a cohort of patients with pleural effusions of different causes. Forty-eight patients had hepatic hydrothorax; 8, heart failure and 45, exudates (9, tuberculosis; 21, malignancies; 10, other). Of the 48 cirrhotic patients, 15 developed SBEM on admission. The pleural fluid of cirrhotic patients showed significantly lower levels of total protein, complement, and opsonic activity than did the fluids of patients with other causes of SBEM. Patients who developed SBEM had lower concentrations of pleural fluid total protein and C3 and had a higher Child-Pugh score than patients who did not develop the infection. Cirrhotic patients with hepatic hydrothorax have lower pleural fluid opsonic activity and C3 levels than those found in the pleural fluid of patients with other causes. Patients who develop SBEM have lower levels of pleural fluid C3, pleural fluid total protein, and a higher Child-Pugh score than those who do not develop SBEM.

Analysis of transtracheal aspirates and pleural fluid from clinically healthy llamas (Llama glama).

Seventeen clinically healthy adult llamas were used to study the characteristics of transtracheal aspirates (TTA) and pleural fluid samples. Results of complete blood counts, fibrinogen determination and thoracic radiographs were within normal limits prior to sampling. Cytologic evaluation of TTA revealed the majority of cells were vacuolated macrophages (60-100%), with 0-40% neutrophils, and fewer lymphocytes (0-1%), eosinophils (0-3%), and ciliated respiratory epithelial cells (0-10%). In TTA from 10 of 17 llamas, neither aerobic nor anaerobic bacteria were isolated. Bacteria isolated in pure culture from TTA were similar to isolates found in clinically healthy animals of other species, and included Acinetobacter sp., Staphylococcus sp. and Bacillus sp. Results (mean +/- SD) of pleural fluid analyses were: total nucleated cell count 576 +/- 361/microliter; specific gravity 1.0133 +/- 0.002; glucose concentration 135.1 +/- 9.02 mg/dL; and lactate concentration 2.95 +/- 1.34 mg/dL. Pleural fluid total protein concentrations determined by refractometry ranged from < 2.5 to 3.5 g/dL. The refractive index ranged from 1.3396 to 0.0013. In pleural fluid, small lymphocytes were the predominant cell type.

Pleural Effusions Following Lung Transplantation: Time Course, Characteristics, and Clinical Implications

The time course and characteristics of ipsilateral pleural effusion in nine consecutive single lung transplant recipients are described and compared with those of six patients who underwent other cardiothoracic operations. Ipsilateral pleural fluid occurs in all lung transplant recipients, beginning immediately following transplantation and continuing for up to 9 days. Pleural fluid immediately after lung transplantation is bloody, exudative, and neutrophil predominant, which is similar to the characteristics of pleural fluid following other cardiothoracic surgery. Pleural fluid cellularity, lactate dehydrogenase, and total protein content decrease rapidly over the first week in lung transplant recipients. The percentage of neutrophils decreases from 90 to 50% by day 7. Pleural fluid output in lung transplant recipients declines steadily during the first week and is minimal by day 9. Pleural fluid output declines more rapidly in patients who have undergone cardiothoracic surgery than in the lung transplant recipients. An early rise in pleural fluid output may reflect the development of posttransplant pulmonary edema. We conclude that it is unnecessary to analyze pleural fluid after lung transplantation if the pleural fluid output is decreasing and the clinical course is appropriate.

Characteristics of normal rabbit pleural fluid: physiologic and biochemical implications.

Each normal rabbit pleural space contains approximately 0.2 ml of collectable, clear liquid. This fluid has a total cell count of 1503±414 cells/mm3, the majority of which are monocytic cells. Pleural fluid total protein concentration (1.4±0.1 gm/100 ml) is approximately 20%, and lactic dehydrogenase concentration (129±6 Wrobleski U/ml) is approximately 40% of that found in blood. Pleural fluid and blood glucose were equivalent, and venous serum chloride concentration was slightly higher than the simultaneously measured pleural fluid value. Normal rabbit pleural fluid is alkaline; the value of 7.66±0.02 probably is slightly higher than the actual pH value owing to the escape of CO2. A 8–9 mEq/liter HCO 3 − gradient was found between pleural fluid and venous blood. The HCO 3 − gradient cannot be explained by the Gibbs-Donnan equilibrium, suggesting that a process of active transport, possibly chloride pumping, is involved.