How Long After Prostrate Surgery Will Urinary Retention Gets Corrected?

Good evening . My husband had a prostate bx 6 dayas ago. We have been to E.R. X3 since ...first time for U.T.I.... Second time for urinary retention .. Catheter was inserted and connected to straight drainage . Was removed this a.m.after 36hours ...3rd time was this p.m. as he was unable to void ...Catheter was reinserted and will remain in until Thurs a.m. When it will be removed again . He had his first dose of flo max this eve .. How long can we expect him to have urinary retention after this procedure..I.e. the prostate bx ??? Thankyou YYYY@YYYY