For a better view to avoid accidental trauma and monitoring kidney function during surgery and in the post-surgery period, patients undergoing abdominal operations will usually have a urinary catheter placed in the bladder before the surgery. Traditionally these catheters are retained for 7 days, because a higher incidence of urinary retention is related to early removal of the urinary catheter. However, recently Enhanced Recovery After Surgery presents that urinary catheters placed via the urethra can be withdrawn 48 hours after colon/rectal surgery in patients receiving epidural pain relief.~Longer retaining time of urethral catheter would induce the urinary tract infection while early removal of urethral catheter is considered to develop acute retention of urine due to lack of sensation when the bladder is full. Taking the comfort and mobility for faster rehabilitation of patients into account, the investigators aim at obtain the optimal removal time of urinary catheter after after laparoscopic anterior resection of the rectum~.
Traditionally these catheters are retained for 7 days, because a higher incidence of urinary retention is related to early removal of the urinary catheter. However, recently Enhanced Recovery After Surgery presents that urinary catheters placed via the urethra can be withdrawn 48 hours after colon/rectal surgery in patients receiving epidural pain relief，but there is no clear data on the incidence of urine retention.Longer retaining time of urethral catheter would induce the urinary tract infection while early removal of urethral catheter is considered to develop acute retention of urine due to lack of sensation when the bladder is full. Taking the comfort and mobility for faster rehabilitation of patients into account, the investigators aim at obtain the optimal removal time of urinary catheter after after laparoscopic anterior resection of the rectum