Effect of pyridostigmine on the duration of post-operative ileus after colorectal surgery.

INTERVENTION: Study participants will be undergo standard peri‐operative care as per our current enhanced recovery protocol (ERP). The ERP is standardised to the Royal Adelaide hospital, involving preoperatively educating patients, minimising the amount of bowel preparation, minimal fasting, carbohydrate and immunonutrition drinks. Intraoperatively this protocol aims for euvolemia, antibiotic prophylaxis as per guidelines, antiemetics, opioid sparing, multimodal analgesia and regional blocks where appropriate. Intraoperatively we also aim to avoid hypoxia and hypothermia along with achieving minimally invasive surgery if possible. Postoperatively oral intake, multimodal analgesia, mobilising, DVT prophylaxis, antiemetic therapy and IV therapy is guided by the protocol. In addition patients are randomised to receive either pyridostigmine or placebo. Drug: Pyridostigmine bromide. Dose: 60 mg twice daily. Mode of administration: Oral tablet, blinded from patient and administrating staff by being encapsulated. Duration: Administered from six hours following surgery, until passage of first stool. Drug adherence: Pyridostigmine/placebo will be administered via blinded staff and recorded in the patients electronic medical records. CONDITION: Post‐operative ileus;Post‐operative complications;Colorectal surgery; ; Post‐operative ileus ; Post‐operative complications ; Colorectal surgery Surgery ‐ Other surgery PRIMARY OUTCOME: Duration of post‐operative ileus (POI) measured using GI‐2 composite score. This is a primary outcome calculated from the interval from surgery until first passage of stool AND tolerance of an oral diet.[Patients will be reviewed twice per day from the date of surgery until discharge from hospital (in days) and then reviewed once daily via telephone if they did not achieve their primary outcome at discharge.] SECONDARY OUTCOME: 30‐day post‐operative complication rate (Clavien‐Dindo graded). ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery, until 30 days postoperatively (in days). During this time, post‐operative patients will be reviewed twice daily during hospital admission and the outcome will be determined by clinical assessment. Following discharge or day 30 of admission (whichever comes first) complications would be assessed via telephone.] Direct hospital costs. ; (Obtained from audit of hospital cost coding records)[From the date of surgery until discharge from hospital (in days) through data from cost‐coding staff.] Incidence of nasogastric tube re‐insertion post‐operatively. ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by clinical assessment.] Incidence of vomiting. ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by clinical assessment.] Length of hospital stay. ; [At baseline before the operation and day of discharge.] Post‐operative analgesics used. INCLUSION CRITERIA: INCLUSION CRITERIA: • Patients over 18 years of age • Undergoing treatment from Central Adelaide Local Health Network • Able to consent ; (Obtained from audit of patient medical records)[From the date of surgery until discharge from hospital (in days). ] Patient reported outcome (via the study specific treatment satisfaction questionnaire). ; (Obtained from audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by review of electronic medical records.] Reported adverse events. ; (Obtained from twice daily clinical review and audit of patient medical records and via study specific treatment questionnaire)[From the date of surgery, until 30 days postoperatively (in days). During this time, post‐operative patients will be reviewed twice daily during hospital admission and the outcome will be determined by clinical assessment. Following discharge or day 30 of admission (whichever comes first) complications would be assessed via telephone.] Stool type (via Bristol stool chart). ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by clinical assessment.] Time to first passage of flatus. ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by clinical assessment.] Time to first passage of stool. ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by clinical assessment.] Time to tolerance of solid diet. ; (Obtained from twice daily clinical review and audit of patient medical records)[From the date of surgery until discharge from hospital (in days). During this time, post‐operative patients will be reviewed twice daily and the outcome will be determined by clinical assessment.] • Undergoing elective large or small bowel resection for any indication or undergoing reversal of Hartmann’s or loop ileostomies or formation of stoma procedure will be invited to participate in this study.