Intraoperative Duplex & TCD
Intraoperative Duplex Exams – The intraoperative duplex is performed on both lower extremity bypass grafts and carotid endarterectomy sites by the vascular surgeon who manipulates the ultrasound scan-head within the sterile surgical wound directly on the vessel or graft. A certain degree of technical expertise and knowledge of duplex interpretive criteria are needed. The vascular technologist controls the ultrasound equipment from outside the sterile field. Sterility is achieved by covering the probe with a sterile sheath. Duplex has been shown to be safe and accurate. It is especially helpful in identifying “high risk” reconstructions that call for careful intraoperative assessment of technical precision, and those that may benefit from more frequent post-op surveillance.
Intraoperative Venous Closure Procedure – This procedure is performed for patients with superficial venous reflux. The procedure uses a special system of radiofrequency or laser energy to heat a catheter that is inserted into a saphenous vein. Exposure to intense heat causes the vein wall to collapse and seal shut. The vascular technologist uses the ultrasound system to guide the surgeon placing the catheter into the vein, and to confirm that flow has terminated after the treatment is finished.
Transcranial Doppler (TCD) Monitoring – The ipsilateral middle cerebral artery is monitored during carotid endarterectomy for the presence of cerebral emboli and to help determine if a shunt is necessary during the procedure. Once the patient is admitted to the hospital, a pre-op evaluation is done to find the appropriate transcranial “window” and apply the headgear which holds the Doppler probe in place during surgery. The patient’s intracranial blood flow is monitored closely to identify and count any embolic signatures that may occur during the dissection, endarterectomy, and closing phase, as well as in the recovery room.