Surgical Site Infection Outcomes in Natural Orifice Intracorporeal Anastomosis and Extraction (NICE) Procedure - The NICE Trial

Surgical Site Infection Outcomes in Robotic Natural Orifice Colorectal Resection - The NICE Trial

The goal of this observational study is to learn if a new surgical technique, called the NICE procedure, is as safe as standard methods for treating benign left-sided colon and rectal diseases in adults. The main question it aims to answer is:

Does the NICE procedure lead to similar or lower rates of surgical site infections (SSIs) within 30 days compared to traditional surgery?

Researchers will gather information from hospitals across the country to evaluate how well this procedure works when performed by experienced surgeons in everyday clinical settings.

Participants will:

Have surgery using the NICE procedure, which uses a robotic platform and removes the specimen through a natural opening (the rectum).

Be monitored for any infections or complications after surgery.

Complete surveys to track their recovery, bowel function, and quality of life for up to 6 months.

This study may help improve recovery, reduce pain, and lower infection risk in future colorectal surgeries.

Study Overview

• Status: Enrolling by invitation
• Conditions: Surgical Site Infection; Diverticulitis; Colorectal Surgery; Diverticulitis, Colonic; Robotic Surgical Procedures; Surgical Site Infections; Diverticulitis Colon; Diverticulitis; Perforation, Bowel; Clinical Trials

Detailed Description

Background and Rationale The Natural Orifice Intracorporeal Anastomosis and Extraction (NICE) procedure represents an emerging innovation in minimally invasive colorectal surgery. It combines robotic intracorporeal anastomosis (ICA) with natural orifice specimen extraction (NOSE), typically transrectal, to avoid the need for an abdominal extraction incision. This approach may reduce surgical site trauma, postoperative pain, opioid use, and rates of incisional hernias.

Intracorporeal anastomosis has been widely studied in right-sided colectomies, with consistent evidence showing reduced surgical site infections (SSIs) and improved recovery. However, application to left-sided resections introduces unique challenges. The bacterial density in the left colon and rectum, combined with transrectal manipulation, may increase the risk of deep or organ-space SSIs. While early single-center experiences suggest the NICE procedure may be safe and effective, multicenter validation in a broader clinical setting is needed.

Study Objectives The primary objective of this study is to determine the 30-day incidence of surgical site infections (superficial, deep, and organ-space) in patients undergoing robotic left-sided colorectal resections using the NICE procedure. Secondary objectives include assessment of intraoperative technical performance, perioperative complications, postoperative recovery, and longer-term functional and quality of life outcomes.

Study Design This is a prospective, multicenter, observational cohort study enrolling patients undergoing elective robotic-assisted left colectomy or rectosigmoid resection for benign colorectal disease. All procedures will use the standardized NICE technique. Participating surgeons must have performed at least 20 prior NICE procedures. The study will run over a 24-month accrual period, with each patient followed for at least 6 months postoperatively.

Study Procedures Surgical intervention involves robotic left-sided resection with intracorporeal anastomosis and transrectal specimen extraction. All sites will follow a standardized Enhanced Recovery After Surgery (ERAS) protocol tailored to robotic colorectal surgery. Operative videos will be collected for quality control, ensuring adherence to the defined NICE procedural steps.

Postoperative follow-up includes in-person or remote assessments at 30 days, 3 months, and 12 months. Functional outcomes will be measured using validated questionnaires: Wexner score for fecal incontinence, LARS score for bowel dysfunction, and PROMS-10 for health-related quality of life.

Data Collection and Oversight Clinical data will be collected prospectively using REDCap, a secure, HIPAA-compliant electronic data capture system. All patient data will be pseudonymized. A centralized coordinating center will oversee data integrity, standardization, and site compliance. Surgical cases will be video recorded to ensure procedural fidelity.

Each site must consecutively enroll eligible patients and maintain compliance with protocol-defined ERAS standards. Surgeons will be credentialed based on review of unedited operative videos prior to participation.

Outcomes The primary outcome is the 30-day SSI rate, including superficial, deep, and organ-space infections. Secondary outcomes include intraoperative variables (e.g., operative time, blood loss, conversion rate), postoperative recovery (opioid use, length of stay, complications, readmissions, reinterventions), and long-term outcomes such as hernia formation and bowel function.

Patient-reported outcome measures will be collected preoperatively and at designated follow-up intervals. These include the Wexner score, LARS score, and PROMS-10, allowing for longitudinal evaluation of continence, function, and quality of life.

Sample Size and Statistical Considerations The study is powered to detect non-inferiority in SSI rates compared to conventional techniques. Assuming a historical SSI rate of 5% and a non-inferiority margin of 5%, a sample size of at least 224 patients provides 80% power with a 5% alpha. To accommodate multivariate modeling and variability across sites, the planned enrollment target is 300-400 patients.

Data will be analyzed using multilevel logistic regression to account for center and surgeon-level effects. Sensitivity analyses will be conducted to test robustness of findings. Descriptive and inferential analyses will be used to evaluate changes in quality of life and functional outcomes over time.

Significance This trial aims to provide high-quality evidence on the safety and performance of the NICE procedure for left-sided colorectal surgery. If non-inferiority is demonstrated, the findings may support broader adoption of this technique, with implications for faster recovery, reduced SSI risk, and improved patient experience. By incorporating video-based quality control and standardized ERAS pathways, the study ensures procedural consistency and real-world applicability of results.

• Study Type: Observational
• Enrollment (Estimated): 300

Contacts and Locations

Study Locations

• United States
  • Texas
    • Houston, Texas, United States, 77030
      • Houston Methodist Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from multiple high-volume colorectal surgery centers across the United States that routinely perform robotic-assisted procedures. All participating sites follow a standardized Enhanced Recovery After Surgery (ERAS) protocol and are required to have surgeons experienced in the NICE procedure. The study population will consist of patients scheduled for elective robotic left-sided colectomy or rectosigmoid resection for benign disease, treated in real-world, non-super-selected surgical practice settings.

Description

Inclusion Criteria

1. Diagnosis: Patients must be diagnosed with benign left-sided colon and rectosigmoid disease, including diverticulitis and benign colon neoplasia.

2. Age Requirement: Patients aged 18 years or older. 3. Cancer-Free: There must be no evidence of cancer or metastatic disease in the patients. This includes:

• Colonoscopy with no evidence of malignant lesion in the last 12 months
• CT scan with no concern for malignancy in the prior 6 months

• No other clinical concern for possible malignancy 4. Surgical Eligibility: Patients must be eligible to undergo robotic left colectomy with primary anastomosis without a planned diverting stoma.

  5. Informed Consent: Participants must be able to understand and willing to sign a written informed consent form.

  6. Treatment with NICE: Patients who undergo surgical treatment specifically with the NICE procedure.

  7. Surgeon Experience: The patients should be treated by surgeons who have performed at least 20 NICE procedures.

  8. General Practice Inclusion: Patients treated by surgeons who offer the NICE procedure as part of their general surgical practice and do not super-select patients for the procedure.

Exclusion Criteria

1. Urgent or emergent procedure

2. Patients diagnosed with cancer or metastatic disease are not eligible for the study. This includes:

   • Known genetic predisposition to colorectal cancer
   • First-degree family history of colorectal cancer
   • Any concern about colorectal cancer
3. Patients with an ongoing infection other than diverticulitis (e.g., pneumonia) or taking antibiotics unrelated to diverticulitis.
4. Patients with a history of pelvic radiation
5. Patients with prior anorectal surgery or prior colorectal surgery
6. Patients with fecal incontinence, outlet obstructive defecation, anismus, or levator spasm at baseline are excluded from the study
7. Any procedure in which a primary anastomosis is not feasible or diversion of the fecal stream is anticipated
8. Patients with a high ASA of 4 or more and clinical frailty score of 8 or more
9. Patients requiring preoperative nutritional support, such as total parenteral nutrition (TPN) or enteral feeding via percutaneous endoscopic gastrostomy (PEG) or nasogastric (NG) tube within 30 days prior to surgery

10. Systemic steroids used within the last 12 months or immunomodulators and biological agents used within the last 60 days prior to surgery will render the patient ineligible for the trial.

    • Preoperative antibiotics used within two weeks to treat diverticulitis are permitted.
    • Antibiotics used within 30 days before surgery for any condition other than treating an infection related to diverticulitis will render the patient ineligible for the trial.
11. Regional block anesthesia (e.g., epidural and spinal) is not permitted in this trial.
12. Chronic Opioid Use: Chronic use of opioids in the prior 3 months.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

NICE Procedure Cohort; This cohort includes patients undergoing elective left-sided colectomy or rectosigmoid resection for benign disease using the robotic Natural Orifice Intracorporeal Anastomosis and Extraction (NICE) procedure. The procedure involves robotic intracorporeal anastomosis and transrectal specimen extraction. No comparator or control group is used. Data collected will assess surgical site infection rates and recovery outcomes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
30-Day Surgical Site Infection (SSI) Rate Following the NICE Procedure	Measures the proportion of patients who develop surgical site infections (SSIs) categorized as superficial, deep, or organ-space within 30 days following robotic left-sided colectomy or rectosigmoid resection using the NICE procedure. Infections are classified per CDC definitions and assessed through clinical evaluation, medical records, and follow-up.	30 days post-surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Long-Term Outcomes: Hernia, Bowel Dysfunction, Fecal Incontinence	Monitors incidence of incisional hernia, long-term bowel dysfunction, and persistent fecal incontinence following the NICE procedure.	Up to 6 months post-surgery
Estimated Intraoperative Blood Loss	Records the estimated blood loss in milliliters during the NICE procedure as documented by the surgical team.	During surgery
Total Operative Time	Measures the total duration of the NICE procedure from skin incision to closure, reported in minutes.	During surgery
Success Rate of Intracorporeal Anastomosis	Captures whether the intracorporeal anastomosis (ICA) was successfully completed as intended using the robotic platform.	During surgery
Success Rate of Transrectal Specimen Extraction	Measures whether the surgical specimen was successfully extracted through the rectum without conversion to transabdominal extraction.	During surgery
Incidence of Intraoperative Complications	Reports the occurrence of intraoperative complications such as rectal tear, sphincter injury, or conversion to open surgery.	During surgery
Total Opioid Use Within 30 Days Post-Surgery	Measures the cumulative opioid consumption during the first 30 days following surgery, expressed in morphine milligram equivalents (MME).	30 days post-surgery
Length of Hospital Stay	Measures the number of days from the date of surgery to the date of discharge, assessing early recovery and discharge readiness.	30 days post-surgery
Overall Postoperative Complication Rate	Proportion of patients who experience one or more postoperative complications, including minor and major events, within 30 days of surgery.	30 days post-surgery
Reoperation or Re-intervention Rate	Proportion of patients who require unplanned surgical reoperation or interventional procedures (e.g., drainage) within 30 days post-surgery.	30 days post-surgery
Readmission Rate Within 30 Days	Percentage of patients who are readmitted to any hospital for any cause within 30 days following the index surgery.	30 days post-surgery
Postoperative Mortality Rate	Percentage of patients who die from any cause within 30 days following the surgical procedure.	30 days post-surgery
Use of Transrectal Wound Protector	Documents whether a wound protector was used during transrectal specimen extraction as part of the NICE procedure.	During surgery
Type of Intracorporeal Anastomosis Staple Line	Classifies the anastomosis as either crossing or non-crossing staple line configuration.	During surgery
Oversewing of Anastomosis	Indicates whether the anastomosis was reinforced with oversewing after stapling.	During surgery
Performance of Mesenteric Shaving	Captures whether mesenteric shaving was performed on the specimen during the NICE procedure.	During surgery
Stool Contamination Grade During NICE Procedure	Assesses the degree of fecal contamination encountered intraoperatively using a standardized grading scale. Scale Components and Interpretation: Degree of Contamination (Severity of contamination encountered): 1 = Mild (Minimal stool, easily managed with minimal delay); 2 = Moderate (Requires additional cleaning, minor to moderate delays); 3 = Severe (Substantial contamination, extensive cleaning and procedural delay required) Higher scores indicate worse contamination. Quality of Contamination (Consistency of stool): Liquid = Easily aspirated; Semi-formed = Partially cleared with aspiration; Solid = Requires transrectal/manual clearing Degree of Evacuation (Effectiveness of stool clearance): Complete = All visible stool removed; Semi-complete = Minimal residual stool; Incomplete = Moderate residual stool	During surgery
Change in Wexner Score for Fecal Incontinence	Evaluates changes in the Wexner score from baseline at 3 and 12 months to assess the severity and frequency of fecal incontinence following the NICE procedure. The Wexner score assesses the ability to control gas, liquid, and solid stool, the need for protective garments, and the impact on lifestyle. Scale Range: 0 (no incontinence) to 20 (complete incontinence); Higher scores indicate worse fecal incontinence.	Baseline, 3 months, 12 months
Functional Outcomes: LARS Score	The Low Anterior Resection Syndrome (LARS) score assesses bowel dysfunction including incontinence, frequency, and urgency following low anterior resection. Evaluates changes over time. Scale Range: 0 to 42; Scores 0-20 indicate no LARS, 21-29 minor LARS, and 30-42 major LARS. Higher scores indicate worse bowel dysfunction.	Baseline, 3 months, 12 months
Health-Related Quality of Life: PROMS-10 Score	PROMS-10 captures patient-reported physical, emotional, and social well-being using a 10-item questionnaire. Monitors change in health-related quality of life over time. Scale Range: 0 to 40; Higher scores indicate better quality of life.	Baseline, 3 months, 12 months

Collaborators and Investigators

• Sponsor: The Methodist Hospital Research Institute
• Investigators: Principal Investigator: Eric M Haas, MD, The Methodist Hospital Research Institute; Study Director: Muhammed Elhadi, MBBCh, The Methodist Hospital Research Institute

Study record dates

Study Major Dates

• Study Start (Actual): April 2, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): December 30, 2026

Study Registration Dates

• First Submitted: April 4, 2025
• First Submitted That Met QC Criteria: April 25, 2025
• First Posted (Actual): May 4, 2025

Study Record Updates

• Last Update Posted (Actual): May 8, 2025
• Last Update Submitted That Met QC Criteria: May 5, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Keywords: Surgical Site Infection; Diverticulitis; Minimally Invasive Surgery; Surgical Outcomes; Intracorporeal Anastomosis; Natural Orifice Specimen Extraction; Robotic Colorectal Surgery; Left Colectomy; Rectosigmoid Resection; Benign Colorectal Disease; Robotic Surgery Outcomes
• Additional Relevant MeSH Terms: Diverticular Diseases; Postoperative Complications; Pathologic Processes; Disease Attributes; Intestinal Diseases; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Gastroenteritis; Wound Infection; Diverticulosis, Colonic; Infections; Communicable Diseases; Surgical Wound Infection; Diverticulitis; Diverticulitis, Colonic
• Other Study ID Numbers: PRO00038141

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data (IPD) will not be shared outside the study team due to privacy concerns and the multicenter observational nature of the study. Although data are pseudonymized, the complexity and volume of surgical video and clinical data could still risk indirect identification. Data access is restricted to investigators approved by the study's steering committee to ensure confidentiality and ethical compliance.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No