Abstract: Objective To explore the clinical efficacy of rectal drainage combined with ulinastatin in the prevention of low rectal anastomotic leakage (AL). Methods A prospective randomized controlled study was conducted,100 patients with low rectal cancer scheduled for radical resection in our hospital from March 2022 to October 2024 were enrolled,and they were divided into two groups used random number table method.The experimental group (50 cases) received rectal drainage combined with ulinastatin ,while the control group (50 cases) received conventional basic treatment.The incidence of AL,surgery time,intestinal anastomosis time,intraoperative blood loss,postoperative bleeding,postoperative gastrointestinal function recovery time,average hospital stay,postoperative complications,and changes in inflammatory response and hemorheology indices before and after treatment were compared between the two groups. Results The incidence of AL and complications in the experimental group were lower than those in the control group (P<0.05),and the postoperative gastrointestinal function recovery time and hospital stay were shorter than those in the control group (P<0.05).Serum levels of procalcitonin（PCT）,C-reactive protein（CRP）,tumor necrosis factor-α（TNF-α）,interleukin（IL）-6 at 3 days (M₂) and 7 days (M₃) postoperatively and plasma viscosity,erythrocyte aggregation index,and whole blood viscosity at immediate anastomosis (M₀) and 1 day (M₁) postoperatively decreased(P < 0.05).And serum levels of PCT,CRP,TNF-α,IL-6,plasma viscosity,red blood cell aggregation index,and whole blood viscosity in experimental group at M_2-3were lower than those in the control group (P<0.05). Conclusion Rectal drainage combine with ulinastatin can effectively inhibit inflammatory response,improve hemorheology,reduce the incidence of AL and infection after radical resection of low rectal cancer,and accelerate postoperative recovery.

Key words: low rectal cancer; anastomotic leakage; rectal drainage; ulinastatin; inflammatory response; hemorheology