The ICCAUT-1 trial failed to demonstrate the superiority of the ICCAUT strategy in urinary dysfunction. Therefore, there is no need to conduct subsequent trials.

The objective of this trial is to investigate the effect of bladder training on the incidence of re-catheterization after proctectomy. In this study, the bladder training include intermittent urethral catheter clamping combined with active urination training, which we called ICCAUT strategy. This prospective, single-center, randomized controlled trial will enroll patients with rectal cancer who will be randomized in a 1:1 ratio to the ICCAUT group or the free-drainage group. In the ICCAUT group, patients will undergo intermittent clamping of the urinary catheter before its removal. Each time the catheter is released, we will encourage the patients to actively initiate urination to facilitate complete bladder emptying. While patients in the free-drainage group will not undergo any specific training. The urinary catheter will be removed on the second postoperative day for both groups. The primary endpoint is the incidence of re-catheterization due to urinary retention. Secondary endpoints include urinary tract infection (UTI), time of first urination after catheter removal, residual urine volume after the first urination, postoperative morbidity and mortality within 30 days, as well as urinary function within 30 postoperative days.

Urinary catheter placement is a standard procedure before proctectomy. However, the necessity of bladder training prior to catheter removal remains uncertain. The objective of this trial is to investigate the effect of bladder training on the incidence of re-catheterization after proctectomy. In this study, the bladder training include intermittent urethral catheter clamping combined with active urination training, which we called ICCAUT strategy. This prospective, single-center, randomized controlled trial will enroll patients with rectal cancer who will be randomized in a 1:1 ratio to the ICCAUT group or the free-drainage group. In the ICCAUT group, patients will undergo intermittent clamping of the urinary catheter before its removal. Each time the catheter is released, we will encourage the patients to actively initiate urination to facilitate complete bladder emptying. While patients in the free-drainage group will not undergo any specific training. The urinary catheter will be removed on the second postoperative day for both groups. The primary endpoint is the incidence of re-catheterization due to urinary retention. Secondary endpoints include urinary tract infection (UTI), time of first urination after catheter removal, residual urine volume after the first urination, postoperative morbidity and mortality within 30 days, as well as urinary function within 30 postoperative days.

Inclusion Criteria:

1. Patients with a confirmed preoperative diagnosis of rectal cancer.
2. Patients with tumors located below the rectosigmoid junction, as determined by preoperative computed tomography (CT) or rectal magnetic resonance imaging (MRI).
3. Patients undergoing laparoscopic or robotic-assisted total mesorectal excision (TME) for rectal cancer.

Exclusion Criteria:

1. History of abdominal surgery involving the rectum, sigmoid colon, left hemicolectomy, bladder resection or partial resection, prostate surgery, or hysterectomy.
2. History of urethral injury, cranial surgery, spinal surgery, stroke with limb dysfunction, or Parkinson's disease.
3. Inability to urinate through the urethra preoperatively due to various reasons (e.g., ureteral puncture or ureterostomy).
4. Presence of urinary tract infection preoperatively.
5. Previously diagnosed with bladder overactivity syndrome, urinary retention or voiding dysfunction, or diabetic bladder disease.
6. Concomitant resection of other pelvic organs was performed during surgery, including the bladder, prostate, uterus, cervix, and vagina, except for simple adnexal resection.
7. Lateral lymph node dissection for rectal cancer.
8. Injury to the ureter, bladder, or urethra during the perioperative period.
9. Preoperative renal dysfunction (serum creatinine level >133 μmol/L).
10. Emergency surgery.
11. Male patients with preoperative benign prostatic hyperplasia receiving medication treatment.
12. Patients with a ureteral stent or ureteral stricture, or bilateral hydronephrosis.
13. Conversion to open surgery.

Withdrawal Criteria:

After randomization, patients will be withdrawn from the trial if the following situations occur:

1. Inability to remove the urinary catheter within 5 days postoperatively due to various reasons (e.g., impaired consciousness, transfer to the intensive care unit (ICU), Sequential Organ Failure Assessment (SOFA) score ≥2, etc.).
2. Secondary catheterization was performed after catheter removal for reasons other than urinary retention (e.g., secondary surgery, shock, rectal bladder leakage, ureteral leakage, or urethral injury).
3. Patient requests to withdraw from the study at any time during the entire study process.
4. Selective α1-adrenergic receptor blocker is used during the first catheterization of the patient due to medical necessity.

If other researchers can provide valid reasons or demonstrate a need for additional collaboration, we may consider to share the data upon their request after we complete ours study.

after we complete ours study.

Researchers can provide valid reasons or demonstrate a need for additional collaboration with us

The patients and bedside nurses cannot be blinded, but the attending physicians and the medical ultrasound doctor will be blinded. The medical team will ensure that the patients and bedside nurses keep the group assignment confidential from the attending physicians and the medical ultrasound doctor. Unblinding will occur when the patient is discharged, and any instances of premature unblinding will be recorded. Additionally, the data analysts involved in this study will be blinded.