Thanks for your query.Based on the facts that you have posted it is clear that there was injury
while passing the catheter Since the catheter is reintroduced and catheter is draining you have just to keep him catheterised till the urine gets clear. Initially he is bound to pass some blood in the Urine.but once the bleeding stops which takes normally 2-3 days he will pass clear urine. He has to be on antibiotics till he is catheterised to prevent infection. .You have to observe his urine stream in future for 2-3 months to rule out any possibility of developing traumatic stricture of the Urethra.