Vasopressin serum levels in patients with severe brain lesions and in brain-dead patients.
BACKGROUND
Patients with severe brain lesions (SBL) and brain-dead patients (BD) frequently present with vasopressin (AVP) secretion disorders.


OBJECTIVE
To evaluate AVP serum levels in SBL and BD patients.


METHODS
Prospective, open label, observational trial.


METHODS
A general teaching hospital.


METHODS
Three groups of adult subjects (age> 18y) of both sexes were included in this study: control group: 29 healthy volunteers; SBL group: 17 patients with Glasgow Coma Scale (GCS)< 8; and BD group: 11 brain-dead patients. Samples of venous blood were collected in the morning at rest from healthy volunteers and at 8 hourly intervals over a period of 24h from SBL and BD patients for AVP determinations. Concomitantly, some clinical and laboratorial variables were also recorded.


RESULTS
AVP serum levels (pg/ml) were [mean (SD); median]: control [2.2(1.1); 2.0]; SBL [5.7(6.3); 2.9]; and BD [2.6(1.0); 2.8]. AVP serum levels varied greatly in SBL patients, but without statistically significant difference in relation to the other groups (p=0.06). Hypotension (p=0.02), hypernatremia (p=0.0001), serum hyperosmolarity (p=0.0001) and urinary hypoosmolarity (p=0.003) were outstanding in BD patients when compared with SBL.


CONCLUSIONS
The AVP serum levels did not demonstrate significant statistical difference between the groups, only showing a greater variability in SBL patients (manifested as serum spike levels). Hypernatremia and hyperosmolarity were present in BD patients, indicating a failure of the hypothalamic-pituitary system in AVP production and release.
Cintra
Eliane de Araújo
Ede A
Department of Neurology, Faculty of Medical Sciences, State University of CampinasRecife, PE, Brazil. eliane.cintra@bol.com.br
Maciel
Jayme Antunes
JA
Araújo
Sebastião
S
Castro
Margaret de
Md
Martins
Edna Freitas
EF
Falcão
Antônio Luiz Eiras
AL
Sardinha
Luiz A C
LA
Terzi
Renato G G
RG
Dragosavac
Desanka
D
Cardoso
Ana Paula Devite
AP
Oliveira
Rosmari A R A
RA
D000328:Adult; D001127:Arginine Vasopressin / Q000097:blood* / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D001926:Brain Death / Q000097:blood*; D001930:Brain Injuries / Q000097:blood*; D004812:Epidemiologic Methods; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D009994:Osmolar Concentration
D015415:Biomarkers; D001127:Arginine Vasopressin