Sonoclot analysis in elderly compared with younger patients undergoing coronary surgery.
BACKGROUND
The Sonoclot analyzer is a point-of-care method for assessment of the clotting mechanism in whole blood. The results are available within 20 min. The aim of the present study was to investigate whether repeated Sonoclot analyses could identify peri-operative differences in hemostatic function between elderly and younger patients undergoing coronary artery bypass grafting (CABG). In addition, we investigated whether Sonoclot analyses could identify disturbances in hemostatic function leading to post-operative bleeding.


METHODS
Twenty-five elderly and 25 younger patients undergoing CABG were included. Blood samples for Sonoclot analyses were drawn pre-operatively, during surgery, and during the first 20 post-operative hours. The Sonoclot variables sonACT, clot rate, time-to-peak, amplitude of the peak, and R3 were analyzed, and the results were compared between the two groups. Post-operative blood loss volumes were recorded and correlated to the Sonoclot variables. The Sonoclot variables were also correlated to previously reported results on various hemostatic variables measured in the same patient population.


RESULTS
There was a significant difference in sonACT between the two groups (P=0.018). There were no differences between the groups in any of the other Sonoclot variables. There were no significant correlations between any of the Sonoclot variables and post-operative bleeding, or between the Sonoclot variables and other hemostatic variables.


CONCLUSIONS
The difference in sonACT between the two groups indicates a reduced hemostatic function in the elderly patients. However, repeated Sonoclot analyses were not able to identify more specific disturbances in hemostatic function, and did not predict increased post-operative bleeding.
Pleym
H
H
Department of Cardiothoracic Anesthesia and Intensive Care, St. Olav University Hospital, Trondheim, Norway. hilde.pleym@stolav.no
Wahba
A
A
Bjella
L
L
Stenseth
R
R
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D000925:Anticoagulants / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D001780:Blood Coagulation Tests / Q000295:instrumentation* / Q000706:statistics & numerical data; D001026:Coronary Artery Bypass; D004867:Equipment Design; D005260:Female; D006474:Hemorrhagic Disorders / Q000097:blood / Q000139:chemically induced / Q000175:diagnosis*; D006493:Heparin / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007431:Intraoperative Complications / Q000097:blood / Q000175:diagnosis* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D019095:Point-of-Care Systems; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis* / Q000517:prevention & control; D019106:Postoperative Hemorrhage / Q000097:blood / Q000209:etiology / Q000517:prevention & control; D011292:Premedication; D011300:Preoperative Care / Q000379:methods
D000925:Anticoagulants; D006493:Heparin