**10. Procedures to be carried out in the anastomotic leak depending on its severity**

The International Study Group of Rectal Cancer proposed a definition of anastomotic leakage based on **severity grading** for surgical intervention. Grade A anastomotic leakage results in no change in patients' management, whereas grade B leakage requires active therapeutic intervention but is manageable without re-laparotomy. Grade C anastomotic leakage requires re-laparotomy [1]. However, other studies prefer to characterize CAL in two subsets: free and contained leakages. Free leakage

presents significant anastomotic disruption with generalized peritonitis, while contained leakage presents as a minor anastomotic defect with localized peritonitis, including intra-abdominal abscess and fistula [148, 149]. In the same way, this classification tries to establish a correspondence to aggressive treatment or a procedure more conservative, respectively.

### **10.1 Conservative procedures**

Conservative procedures are the option when patients are clinical and analytically stable and imaging findings can be managed with **antibiotics therapy and/or percutaneous drainage** (**Figure 1a**–**c**). Usually, non-operative management is usually preferred in patients who underwent proximal fecal diversion at the initial operation. In patients without a stoma who do not require abdominal reoperation for a contained pelvic leak, there are several treatment options, including laparoscopic diverting ileostomy combined with trans-anal anastomotic tube drainage, percutaneous drainage, or recently developed **endoscopic procedures**, such as a **stent or clip** placement or **endoluminal vacuum-assisted therapy** [122].
