Program Book - Keck School of Medicine of USC - University of ...

• Veins not circular but ovoid, min and max diameters• Higher venous pressure more circular• Patient supine, warm room and gel• Proximal tourniquet, pressure cuff• B mode venous diameters should be determined atvenous pressure >40 mm Hg• Reproducibility with higher with pressure >40 mmHgwww.surgery.usc.eduRelation between the outcome of surgery and preoperativeultrasound assessment. The ultrasound scan is defined asabnormal if the vessel is of diameter less than 1.5 mm and/or astenosis is detected in the cephalic veinUltrasoundAssessmentOutcomeFailed Successful TotalAbnormalNormalTotal1791603838174754Wong Eur J Vasc Endovasc Surg 1996; 12:207-213www.surgery.usc.eduRelative frequencies of each access type placed during the twoperiodsBeforeinstitutionNoninvasiveprotocolof protocolAutogenous fistula* 14% 63%Bridging grafts 62% 30%Permanent catheter 24% 7%Prevalence significantly different in each group (p < 0.05). From June1992 to August 1994, 183 procedures were performed before institutionof protocol. From September 1994 to April 1996, 172 procedures wereperformed with noninvasive protocol.Silva J Vasc Surg 1998;27:302-8www.surgery.usc.edu24