[Blood lactate concentration as prognostic marker in critically ill children].
OBJECTIVE
To assess the use of lactate as a marker of tissue hypoperfusion and as a prognostic index in critically ill patients.


METHODS
Prospective, longitudinal, observational study of 75 patients admitted to the pediatric ICU of Hospital de Clínicas of Universidade Federal do Paraná, between November 1998 and May 1999. According to the lactate level on admission, patients were divided into group A (lactate > or = 18 mg/dl) and group B (lactate < 18 mg/dl). In terms of outcome, patients were classified into survivors and nonsurvivors. In group A, the clinical evaluation and the collection of arterial blood samples were performed on admission, at 6, 12, 24, 48 hours, and every 24 hours after that. In group B, they were carried out in the same way, but interrupted 48 hours after admission.


RESULTS
Groups A and B consisted of 50 and 25 patients, respectively. Group A presented more clinical signs of hypoperfusion (24/50). There was a statistically significant difference regarding the mean lactate levels on admission between those patients who died within 24 hours of admission (95 mg/dl) and those who died 24 hours after admission (28 mg/dl). The lactate level at 24 hours of admission revealed better sensitivity (55.6%) and specificity (97.2%) as a predictor of death.


CONCLUSIONS
Most patients with lactate levels > or = 18 mg/dl showed clinical signs of hypoperfusion on admission. The normalization or reduction of lactate levels at and after 24 hours of admission was significantly related with higher chances of survival.
Koliski
Adriana
A
Universidade Federal do Paraná (UFPR), Curitiba, PR, Brazil. akoliski@yahoo.com.br
Cat
Izrail
I
Giraldi
Dinarte J
DJ
Cat
Mônica L
ML
D000140:Acidosis, Lactic / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D001775:Blood Circulation / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D016638:Critical Illness; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology; D007223:Infant; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D011379:Prognosis; D012769:Shock / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D013997:Time Factors
D015415:Biomarkers; D019344:Lactic Acid