Electromotive Drug Administration (EMDA) in the Porcine Ureter: First Report of In Vivo Ureteral Dilation Following Alfuzosin Infusion "Presentation" - Victor Pham
April 28, 2025
Victor Pham presents a study on electromotive drug administration (EMDA) that significantly enhances alfuzosin penetration through the ureteral wall. This study offers a promising solution for improving surgical access during challenging stone procedures by overcoming the urothelium's natural impermeability to smooth muscle relaxants.
Biography:
Victor Pham, Department of Urology, University of California, Irvine, Irvine, CA
Biography:
Victor Pham, Department of Urology, University of California, Irvine, Irvine, CA
Read the Full Video Transcript
Victor Pham: Dear viewers, my name is Victor. And I'll be presenting, Electromotive Drug Administration in the Porcine Ureter: First Report of in vivo Ureteral Dilation Following Alfuzosin Infusion.
Stone surgery is not always smooth sailing, as some patients have narrow ureters that limit renal access. But what if we can acutely dilate the ureter for better access? We can do so by locally administering smooth muscle relaxants. The only problem is that this approach is limited by the impermeability of the urothelium.
So how can we go around this issue? We can do so with electromotive drug administration, as previous studies have shown that electromotive drug administration, or EMDA, enhances drug delivery. As such, we investigate the effects of EMDA-mediated delivery of alfuzosin on porcine ureteral dilation.
12 female juvenile Yorkshire pigs underwent bilateral ureteral sizing with sequential Cook urethral dilator insertions in 2 French increments up to 3.5 Newtons of force pre-EMDA, immediately post-EMDA, and 20 minutes post-EMDA. Alfuzosin or saline was infused at 5 milliliters per minute for 20 minutes, bilaterally. One ureter was treated with a 10 milliamp pulsed direct current, while the contralateral served as passive diffusion.
Ureter size was measured by assigning 1 unit for each dilator progression from one ureteral region to the next. Generalized estimating equations and ANOVA analyze data. Matrix-assisted laser desorption/ionization mass spectrometry imaging, MALDI-MSI, was used to detect alfuzosin within porcine ureteral tissues.
We found that alfuzosin with EMDA significantly increased ureteral size immediately after EMDA compared to passive diffusion in both controls with an increase of 2.67 units, which is nearly 1 French, with 3 units equating to 1 French. Although to a lesser extent, we also see this dietary effect after 20 minutes after EMDA, with an increase of 1.33 units-- a little under half a French.
The MALDI-MSI spectra demonstrate a 12-fold increase in the alfuzosin delivery in ureters treated with EMDA, represented by the red peak, compared to passive diffusion, represented by the blue peak. We can see this clear difference in the MALDI images, in which EMDA with alfuzosin shows substantial deposition beyond the urothelium, while passive diffusion is virtually zero.
To conclude, EMDA-mediated ureteral infusion of alfuzosin achieved greater drug penetration, and significantly increased porcine ureter distensibility, compared to passive diffusion. Thank you.
Victor Pham: Dear viewers, my name is Victor. And I'll be presenting, Electromotive Drug Administration in the Porcine Ureter: First Report of in vivo Ureteral Dilation Following Alfuzosin Infusion.
Stone surgery is not always smooth sailing, as some patients have narrow ureters that limit renal access. But what if we can acutely dilate the ureter for better access? We can do so by locally administering smooth muscle relaxants. The only problem is that this approach is limited by the impermeability of the urothelium.
So how can we go around this issue? We can do so with electromotive drug administration, as previous studies have shown that electromotive drug administration, or EMDA, enhances drug delivery. As such, we investigate the effects of EMDA-mediated delivery of alfuzosin on porcine ureteral dilation.
12 female juvenile Yorkshire pigs underwent bilateral ureteral sizing with sequential Cook urethral dilator insertions in 2 French increments up to 3.5 Newtons of force pre-EMDA, immediately post-EMDA, and 20 minutes post-EMDA. Alfuzosin or saline was infused at 5 milliliters per minute for 20 minutes, bilaterally. One ureter was treated with a 10 milliamp pulsed direct current, while the contralateral served as passive diffusion.
Ureter size was measured by assigning 1 unit for each dilator progression from one ureteral region to the next. Generalized estimating equations and ANOVA analyze data. Matrix-assisted laser desorption/ionization mass spectrometry imaging, MALDI-MSI, was used to detect alfuzosin within porcine ureteral tissues.
We found that alfuzosin with EMDA significantly increased ureteral size immediately after EMDA compared to passive diffusion in both controls with an increase of 2.67 units, which is nearly 1 French, with 3 units equating to 1 French. Although to a lesser extent, we also see this dietary effect after 20 minutes after EMDA, with an increase of 1.33 units-- a little under half a French.
The MALDI-MSI spectra demonstrate a 12-fold increase in the alfuzosin delivery in ureters treated with EMDA, represented by the red peak, compared to passive diffusion, represented by the blue peak. We can see this clear difference in the MALDI images, in which EMDA with alfuzosin shows substantial deposition beyond the urothelium, while passive diffusion is virtually zero.
To conclude, EMDA-mediated ureteral infusion of alfuzosin achieved greater drug penetration, and significantly increased porcine ureter distensibility, compared to passive diffusion. Thank you.