Self-cannulation

What are optimal venous and arterial pressures? I run at a blood flow of 450 and dialysate rate averaging just under 12. Tx time 3.5hr. FF now 47. I have to observe VP at 200. I believe 90 to maybe 120.at 200bf.
My AP averaged 180’s and VP now 175 - 200. My VP used to be @250 for most of tx. But since I was finally allowed to create a new venous buttonhole it dropped. It is the lowest VP pressure I have had since starting HHD almost a year ago. Like my BUN and creatinine my Vp droppped dramatically (60%).
BUN n Creatnine went down by 60% right after a recent fistulogram and new venous buttonhole. Now from your site am wondering if my blood flow is too high at 450. Nit looking forward to another battle.