title: Capillary lactic acid validation in an ED.
abstract: BACKGROUND
  One of the most used methods to evaluate patients with a high risk not responding to clinical treatment is the measurement of blood levels of lactic acid (LA). The objective of this study was to compare the sensitivity and specificity of an LA test for capillary and venous blood with LA test for arterial blood in a population of patients with tissue hypoperfusion and to evaluate the time needed for each test.
  
  
  METHODS
  The following factors were evaluated: the performance of venous and capillary LA in relation to arterial LA, and the time needed to elicit each method from patient admission to mortality according to initial LA.
  
  
  RESULTS
  Seventy-nine patients with a median age of 58 years were admitted. The area under the curve for capillary LA was 82% (95% confidence interval [CI], 73-91). The best cutoff point was 2.35, with a sensitivity of 81% (95% CI, 65-90) and a specificity of 70% (95% CI, 53-83). The average time from patient admission until arterial, venous, and capillary LA values were obtained was 112, 117, and 77 minutes, respectively. The patients who died within 3, 30, and 60 days showed an average arterial LA of 5.9, 1.9, and 2.2, respectively.
  
  
  CONCLUSIONS
  The utilization of capillary and venous LA is an effective method of evaluation and risk stratification for patients with different degrees of tissue hypoperfusion. The time needed to elicit capillary LA proved much faster with respect to arterial and venous LA.
authors.affiliation: Department of Emergency, Hospital Universitario Austral. Electronic address: lseoane@yahoo.com.
authors.forename: Leandro
authors.initials: L
authors.lastname: Seoane
authors.forename: Marcelo
authors.initials: M
authors.lastname: Papasidero
authors.forename: Paula
authors.initials: P
authors.lastname: De Sanctis
authors.forename: Lourdes M
authors.initials: LM
authors.lastname: Posadas-Martínez
authors.forename: Silvia
authors.initials: S
authors.lastname: Soler
authors.forename: Marcelo
authors.initials: M
authors.lastname: Rodríguez
mesh_terms: D000328:Adult; D000368:Aged; D001158:Arteries; D015415:Biomarkers / Q000097:blood; D001800:Blood Specimen Collection / Q000379:methods; D002196:Capillaries; D004636:Emergency Service, Hospital; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018805:Sepsis / Q000097:blood / Q000401:mortality; D013997:Time Factors; D014680:Veins
chemical_list: D015415:Biomarkers; D019344:Lactic Acid