Hemodynamic changes in the cephalic vein of patients with hemodialysis arteriovenous fistula.

PURPOSE

To assess via Doppler sonography the hemodynamic changes in the cephalic vein after creation of an arteriovenous fistula, and to compare radiocephalic and brachiocephalic fistulas.

METHODS

Thirty-three hemodialysis patients and 54 controls were enrolled in the study. The cephalic vein was examined with a 7.5-MHz linear-array transducer. Doppler waveform parameters (resistance index, pulsatility index), time-averaged maximum flow velocity (TAV), peak systolic velocity (PSV), end-diastolic velocity (EDV), and the cross-sectional area of the vessel (A) were measured. Cephalic vein flow volume (CVFV) was calculated as TAV x A.

RESULTS

CVFV, PSV, EDV, A, RI, and PI were 45.5, 7.2, 6.7, 7.7, 1.2, and 1.32 times higher, respectively, in the cephalic vein of hemodialysis patients compared with controls. Both CVFV and A were higher in brachiocephalic patients compared with radiocephalic patients (1,983 +/- 1,199 versus 870 +/- 322 ml/min [p < 0.05] and 50.3 +/- 38.9 versus 21.0 +/- 7.8 mm(2) [p < 0.05], respectively).

CONCLUSION

The increase in cross-sectional area and flow volume of the cephalic vein is larger in patients with brachiocephalic fistulas than in those with radiocephalic fistulas; however, flow velocities and waveform parameters are not different.