"Simple mistake can cost a life"

My wife has a catheter due to pancreatic cancer and tumours in her back, no use of her legs and one night had 24hr call out carers to the home for some personal care. The carers after changing her forgot to reattach the night bag which meant that urine was feeding back into my wife during the night and wasn't noticed till morning. After opening the valve and letting the night bag fill, I was told she would be ok.  

24 hours later and emergency doctor called, my wife ended up in the back of an ambulance ( 8 hours after being called) with septicemia, temperature, severe pain and in and out of consciousness. Emergency doctor informed me if untreated could have cost her her life. 7 days she spent in hospital due to this one mistake and set her back months in terms of being able to transfer from wheelchair to  chair herself. She no longer has the strength to do this and has been bed ridden for past 10 days. All we got was a sorry with no real follow up.

Hospital and normal carers have been great but we have had no correspondence in connection with this and no real assurance that it won't happen to someone else.