title: Rapid differentiation of pathogenesis in patients with pulmonary edema by protein measurement with refractometer.
abstract: BACKGROUND
  No study has focused on using refractometer to rapidly determine total protein ratio of edema fluid to blood concentration (TPe/TPb) and, to differentiate hydrostatic pulmonary edema (HPE) from adult respiratory distress syndrome (ARDS).
  
  
  METHODS
  The reliability of refractometer was evaluated by correlating the protein concentration measured by refractometer with that by sequential multiple autoanalyzer (SMA) in 91 blood samples. In intensive care unit, thirteen patients with florid pulmonary edema were included. All had an unequivocal diagnosis of either HPE or ARDS. Edema fluid and blood were collected simultaneously for the measurement of protein concentration by refractometer.
  
  
  RESULTS
  Protein concentration measured by refractometer correlated excellently with that by sequential multiple autoanalyzer (r = 0.991, p < 0.00001). In 7 patients with ARDS, the mean TPe/TPb was 0.75 +/- 0.13. In contrast, in 6 patients with HPE, the mean TPe/TPb was 0.36 +/- 0.14. The difference between groups was significant (p < 0.005). An inverse correlation between TPe/TPb and wedge pressure was also significant (r = -0.814, p < 0.001).
  
  
  CONCLUSIONS
  Using refractometer to determine protein ratio of edema fluid to blood concentration can rapidly and effectively distinguish ARDS from HPE in patients with florid pulmonary edema. TPe/TPb correlates inversely with wedge pressure in these patients.
authors.affiliation: Department of Respiratory Therapy, Veterans General Hospital-Taipei, Taiwan, R.O.C.
authors.forename: T C
authors.initials: TC
authors.lastname: Lien
authors.forename: J H
authors.initials: JH
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D015633:Extravascular Lung Water / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011506:Proteins / Q000032:analysis*; D011654:Pulmonary Edema / Q000209:etiology* / Q000378:metabolism; D012031:Refractometry; D015203:Reproducibility of Results; D012128:Respiratory Distress Syndrome / Q000150:complications / Q000175:diagnosis
chemical_list: D011506:Proteins