Brief Answer:
Detailed answer below.

Detailed Answer:
Hi Egsuper,
Thanks for the query. I have read it & understand your concern.

The catheter can be:

1)A permanent catheter or indwelling catheter, or Foley's catheter: it is advised for a long time... such catheters are advised if one can not empty bladder on their own... & retention of urine in the bladder is hazardous to kidney health. (eg: prostate enlargement /surgery or no ability to clear bladder due to damaged nerve supply-as in paralysis)

2)intermittent catheters .. advised in temporary retention of urine /postoperative(prostate surgery)

Now the answer to your query -
- blood on the catheter can be due to trauma to urethra while inserting the catheter, with friction in case of the permanent catheter or due to urine infection, postoperative in case of pelvic or urinary surgeries like surgeries for - prostate removal or tumours.

- The tissue-like debris in catheter could be built up by blood clots, tissue expelled after prostate surgery, different cells in urine or urinary sediments and mucus.

*Management -
-Self care-consists of cleanliness of hands while handling catheter or draining the collection bag /drinking sufficient water./continue taking medicine as per doctor's advise.

-Report to your doctor if there is less or no flow of urine/irritation, swelling or inflammation at the entrance of catheter in body./You have pain in the pelvis, back /there is fever, burning in urine&urine is cloudy or red.

I hope that answers your query. Any follow up query is welcome.
Thanks.

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