Preoperative laboratory evaluation of patients aged over 40 years undergoing elective non-cardiac surgery.
OBJECTIVE
Although it is generally agreed that a medical history and physical examination should be obtained as part of preoperative evaluation, there is still substantial controversy about the additional benefits of preoperative screening tests. The objective of the present study was to determine the percentage of abnormalities on laboratory tests among a population that underwent non-cardiac surgery and to correlate these tests with changes in preoperative evaluation management.


METHODS
Cross-sectional study, carried out in a University Hospital.


METHODS
991 patients aged over 40 years undergoing elective non-cardiac surgery from July 1997 to January 2000 were studied. Blood cell count, serum sodium, potassium, urea and creatinine, prothrombin, thrombin and partial thromboplastin time, electrocardiogram and chest X-ray were evaluated.


RESULTS
Out of the 957 electrocardiograms performed, some type of abnormality was found in 504 cases (50.9%) and, among the 646 chest X-rays requested, 271 (42.0%) displayed alterations. Laboratory tests showed abnormal values ranging from 5.1% (prothrombin time) to 41.0% (hematocrit). Increased percentages of abnormal tests with increasing patient age were also observed.


CONCLUSIONS
Although there were substantial numbers of screening test abnormalities in preoperative evaluations, these results seldom interfered in patient management.
Ajimura
Fábio Yoshito
FY
Department of Medicine, School of Medicine, Universidade de São Paulo, Av. Dr. Arnaldo 455, São Paulo, Brazil CEP 01246-903.
Maia
Alex Silva Santos Freire
AS
Hachiya
Adriana
A
Watanabe
Alexandra Sayuri
AS
Nunes
Maria do Patrocínio Tenório
Mdo P
Martins
Mílton de Arruda
Mde A
Machado
Fábio Santana
FS
D000328:Adult; D000367:Age Factors; D001774:Blood Chemical Analysis; D001780:Blood Coagulation Tests; D003430:Cross-Sectional Studies; D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data*; D017558:Elective Surgical Procedures; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D013902:Radiography, Thoracic