title: [Treatment indication with endothoracic drainage tube in parapneumonic effusions by partial pressure of carbon dioxide measurement in pleural fluid].
abstract: OBJECTIVE
  Parapneumonic effusions with pH < 7.20 or glucose < 0.40 g/l or lactate dehydrogenase (LDH) > 1000 U/l have indication of treatment with endothoracic drainage tube (EDT). The aim of the present study was to determine the accuracy of partial pressure of carbon dioxide (pCO2) measurement in pleural fluid for the subsequent treatment indication with EDT in parapneumonic effusions, by analyzing the area under curve ROC (AUC) and determining the optimal cut off value.
  
  
  METHODS
  207 pleural fluids were studied. Glucose, LDH, pCO2, and pH were measured, and data concerning the etiology of pleural effusion and whether EDT treatment was needed were collected after patients were discharged from hospital.
  
  
  RESULTS
  Forty-six out of 207 pleural fluids studied were parapneumonic effusions. Thirty-two were treated with EDT. AUC values were 0.888 (p < 0.0001), 0.890 (p < 0.0001), 0.816 (p < 0.0001), and 0.801 (p < 0.0001) for pCO2, pH, glucose, and LDH, respectively. No significant differences were found among them. Optimal cut off value for pCO2 was 48.6 mmHg, exhibiting 90.6% sensitivity and 78.6% specificity. All parapneumonic effusions showing pCO2 > 60.9 mmHg were treated with EDT. Remarkably, 3 out of 46 parapneumonic effusions (6.5%) that had been improperly treated following pH, glucose or LDH values, were correctly treated following pCO2.
  
  
  CONCLUSIONS
  pCO2 determination in pleural fluid appears to be the best way to decide the indication of EDT in parapneumonic effusions.
authors.affiliation: Servicio de Bioquímica Clínica, Hospitales Universitarios Virgen del Rocío, Sevilla, España. jose.d@telefonica.net
authors.forename: José Diego
authors.initials: JD
authors.lastname: Santotoribio
authors.forename: Carmen
authors.initials: C
authors.lastname: Delgado-Pecellín
authors.forename: Antonio
authors.initials: A
authors.lastname: León-Justel
authors.forename: Juan Miguel
authors.initials: JM
authors.lastname: Guerrero
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002245:Carbon Dioxide / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D004322:Drainage / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D010313:Partial Pressure; D010996:Pleural Effusion / Q000737:chemistry* / Q000628:therapy*; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D002245:Carbon Dioxide