Does local application of nitrates, during insertion of staplers via anal canal for bowel anastomosis prevent injury to muscles of anal canal ?

Intervention1: 0.2% Glyceryl Trinitrate: 1mg 0.2% glyceryl trinitrate, which corresponds to 2cm on the standardized measuring scale Control Intervention1: Nil: Nil Primary outcome(s): To compare anal sphincter pressure between intervention and observation groupsTimepoint: 1-3 days preoperative and 14-30 days postoperative Study Design: Randomized, Parallel Group Trial Method of generating randomization sequence:Computer generated randomization Method of allocation concealment:Sequentially numbered, sealed, opaque envelopes Blinding and masking:Participant and Outcome Assessor Blinded