Optimized hyperventilation preserves 2,3-diphosphoglycerate in severe traumatic brain injury.
BACKGROUND
The concentration of 2,3-diphosphoglycerate (2,3-DPG/Hct) increases as a physiological occurrence to pH increase and hyperventilation. This response was tested in patients with severe traumatic brain injury (TBI).


METHODS
The concentration of 2,3-DPG/Hct was measured daily for six days in eleven patients with severe TBI in need of optimized hyperventilation because of intracranial hypertension.


RESULTS
There was correlation between pH and the concentration of DPG/Hct. The concentration of 2,3-DPG/Hct remained predominantly within normal levels with slight increase in the sixth day of the study. The concentration of 2,3-DPG/Hct correlated significantly with measured partial pressure of oxygen that saturates 50% the hemoglobin of the blood (P50st), confirming the consistency of our data.


CONCLUSIONS
The expected physiological response of a progressive increase in concentration of 2,3-DPG/Hct to hyperventilation was not observed. This fact may be explained by the intermittent and not sustained hyperventilation as dictated by the protocol of optimized ventilation.
Torres
Rayne Borges
RB
Campinas State University, Campinas, São Paulo, Brazil. raynebt@yahoo.com.br
Terzi
Renato Giuseppe Giovanni
RG
Falcão
Antônio Luís Eiras
AL
Höehr
Nelci Fenalti
NF
Dantas Filho
Venâncio Pereira
VP
D019794:2,3-Diphosphoglycerate / Q000097:blood*; D018806:APACHE; D000293:Adolescent; D000328:Adult; D001784:Blood Gas Analysis; D001930:Brain Injuries / Q000097:blood* / Q000628:therapy; D016022:Case-Control Studies; D002648:Child; D004912:Erythrocytes / Q000737:chemistry; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial
D019794:2,3-Diphosphoglycerate