RESUMO
Transdermal glyceryl trinitrate (GTN) administration may have a beneficial effect in the creation of an arteriovenous fistula (AVF) by increasing blood flow through the access and by inhibiting platelet aggregation. We evaluated the hemodynamic effects of transdermal GTN administration on newly constructed arteriovenous fistula. Radiocephalic fistula at the wrist (Brescia fistula) was constructed as the initial vascular access in 31 uremia patients (study = 16, control = 15). The patient demographics and the etiology of chronic renal disease were similar in the two groups. None of the patients had severe vasculitis. The mean duration of chronic renal disease was 8 months (1-24 months). The diameter, blood flow rate, and blood output at the drainage vein and the subclavian vein were measured by duplex ultrasonography 24 hours after the procedure. The measurements were performed again with transdermal GTN (10 mg/24 hours adhesive patch) administration in the study group and, without any medication, in the control group 4 hours after the initial measurements were taken. In the study group, all of the hemodynamic parameters were significantly increased over the initial measurements (p <0.05) whereas in the control group all hemodynamic parameters were unchanged, except the diameter of the subclavian vein (p <0.05). The actual change in hemodynamic parameters was significant in the study group when compared to the control group (p <0.05). Our data showed that transdermal GTN administration at the forearm increases flow through the Brescia fistula.