# Safety and Feasibility Colorectal Anastomosis Protocol Implementation: Results from the CASPI Single-Arm Pilot Study

## TL;DR

A new protocol called CASPI was tested to improve safety during colorectal surgery and showed promising results in a pilot study.

## Contribution

The CASPI protocol introduces a structured, multimodal approach to assess anastomosis safety during and after colorectal surgery.

## Key findings

- The CASPI protocol was fully adhered to during surgery and showed high postoperative adherence.
- No complications were observed from using the CASPI protocol in 34 patients.
- The protocol confirmed adequate blood supply and anastomotic integrity in most cases.

## Abstract

Anastomotic leakage is one of the most serious complications after colorectal surgery and can greatly affect patients’ recovery and quality of life. Our team developed the CASPI protocol, a step-by-step method that allows surgeons to carefully assess the blood supply, integrity, and safety of the bowel connection during and after the operation. In this pilot study, we applied the protocol to patients with colorectal cancer to evaluate its safety, ease of use, and consistent applicability. The CASPI protocol demonstrated high adherence without causing any complications. These results suggest that the CASPI protocol is safe and support its feasibility for routine clinical practice.

Background/Objectives: Anastomotic leakage (AL) is a major complication of colorectal surgery. Despite multiple identified risk factors, no single strategy has proven fully effective in preventing AL. This single-arm pilot study aims to evaluate the feasibility, safety, and adherence of a multimodal colorectal anastomosis assessment protocol (CASPI) in patients undergoing surgery for colorectal cancer. Methods: This prospective descriptive interventional single-arm pilot study included patients diagnosed with colorectal cancer who underwent surgical resection. The CASPI protocol consists of five steps: (1) indocyanine green (ICG) perfusion assessment, (2) doughnut integrity checking, (3) air leak testing, (4) intraoperative flexible endoscopy, and (5) postoperative flexible sigmoidoscopy. Results: A total of 34 patients were included. The median age was 63.5 years, and the median BMI was 27.7 kg/m2. Twenty-seven patients had rectal tumors, and 66.7% received neoadjuvant therapy. Adherence to the protocol was 100% intraoperatively and 88.2% postoperatively. Adequate perfusion by ICG was confirmed in 94.1% of cases; intact anastomotic doughnuts were obtained in all procedures. Intraoperative endoscopy showed Grade 1 mucosa in 76.5% of patients and Grade 2 in 23.5%. No complications related to the CASPI protocol were observed. Stoma closure was performed in all patients with temporary ileostomy. Conclusions: Implementation of the CASPI protocol in colorectal surgery demonstrated excellent feasibility, high adherence, and strong safety. These findings support its further evaluation in larger, controlled studies designed to assess clinical effectiveness in the incidence of anastomotic complications.