Perioperative Management of a Patient with Severe Factor V Deficiency Presenting with Chronic Subdural Hematoma: A Clinical Report.

BACKGROUND: Severe factor V deficiency is an extremely rare coagulation disorder. Patients with factor V activity <5% usually become symptomatic in early childhood. CASE DESCRIPTION: We report the case of an 82-year-old woman with incidentally diagnosed severe factor V deficiency, who developed a symptomatic chronic subdural hematoma, requiring burr hole craniostomy. Successful management was achieved by a multidisciplinary approach. Preoperatively, factor V activity was increased from 2% to 50% by administration of 25 mL/kg body weight of fresh frozen plasma over 30 minutes under close cardiopulmonary monitoring in the intensive care unit. Straight afterward, the patient was transferred to the operating room where surgery was performed under general anesthesia. Burr hole craniostomy could be performed without perioperative complications. In the postoperative days, there was no relevant recurrence of the subdural hematoma in the follow-up computed tomography scans under frequent control of coagulation parameters. However, despite further transfusion of fresh frozen plasma, factor V activity did not increase >16%. The patient was discharged without any neurologic deficits. In a hemostaseologic follow-up 2 months after surgery, factor V activity <1% was confirmed with evidence of a factor V inhibitor in the modified Bethesda assay. Most likely, the patient suffered from an acquired form of factor V deficiency with preformed antibodies that had been boosted by the initial treatment with fresh frozen plasma. CONCLUSIONS: We conclude that in this rare bleeding disorder, intracranial surgery was successfully managed because of a thoroughly planned perioperative therapeutic strategy. However, if there is time prior to surgery, a full checkup of the bleeding disorder is advisable.

An ultrasonic method to measure human plasma coagulation time.

An ultrasonic method to measure coagulation time for prothrombin time (PT) is discussed. This method is based on the measurement of ultrasonic scattering from spherical glass particles of 200-microns diameter kept in motion, inside of a holder containing 0.1 ml of plasma, by ultrasonic energy. The incident wave (2.7 MHz) not only keeps the particle in motion but also is the source for the scattered waves. A receiving transducer captures part of the scattered wave and generates at its electrical output a signal containing amplitude and phase fluctuations. The motion of the particles are strongly influenced by the rheological changes during the process of coagulation. When the clot is formed, the amplitude of the motion of these particles is significantly reduced and so the fluctuations on the received signal stop. The time from the start of the coagulation process until the end of the fluctuations at the received signal is the coagulation time. Experimental results demonstrate that the ultrasonic method has precision and accuracy compatible to those provided by the manual tilt-tube method when PT is measured with normal and abnormal samples of human plasma.