Perisurgical Monitoring of Activated Coagulation Time in Carotid Endarterectomy

Czech version

Authors: M. Sameš ¹; E. Provazníková ¹; F. Cihlář ²; D. Bejšovec ³; R. Bartoš ¹; A. Hejčl ¹; I. Humhej ¹; P. Vachata ¹
Authors‘ workplace: Krajská zdravotní a. s., Masarykova nemocnice v Ústí nad Labem, o. z. Neurochirurgická klinika UJEP ¹; Krajská zdravotní a. s., Masarykova nemocnice v Ústí nad Labem, o. z. Radiologické odd. ²; Krajská zdravotní a. s., Masarykova nemocnice v Ústí nad Labem, o. z. Odd. intenzivní medicíny ³
Published in: Cesk Slov Neurol N 2011; 74/107(3): 325-329
Category: Short Communication

Overview

The aim of this study was to determine the ideal amount of heparin per kilogram of patient body weight and the amount of protamine necessary for its subsequent neutralization with relation to initial heparin dose and with respect to activated coagulation time (ACT).

Patients and methods:
The prospective study group consisted of 80 patients (20 female, 60 male) 44 of them treated for asymptomatic stenosis, mean age 65.8, range 39–82 years, bilateral stenosis in 4 of them, upon whom a total of 84 carotid endarterectomies had been performed between April 2008 to May 2009. Patients were divided into three groups, according to the amount of heparin administered (1, 1.5 and 2 mg of heparin per kilogram).

Results:
In first group, median ACT after heparin administration was 268.0 seconds; in second 334.0 and in the third group 375.0 (p <0.01). Median ACT after protamine administration in the first group was 130 seconds, in the second 137 seconds and in the third group 128 seconds (p = 0.79). A total of 7 postoperative complications occurred, including 2 wound haematomas requiring surgical revision (2.4%), 3 neurological complications (3.6%) and 2 cardiological complications (2.4%). After three months all patients had recovered ad integrum at ambulatory check-up; permanent morbidity is thus 0%.

Conclusion:
One milligram of heparin per kilogram is a sufficient dose to achieve adequate anticoagulation, minimizing the risk of postoperative haematoma without increasing the risk of peri-operative ischemic stroke.

Key words:
carotid endarterectomy – activated coagulation time – heparin – protamine

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