OT notes · General Surgery

Fistula-in-ano: fistulotomy / seton (including Ksharsutra)

Usual anaesthesia
Spinal (saddle); general for prone position or when required
Position
Lithotomy
Setting
elective

Operative note template for examination under anaesthesia of a fistula-in-ano with fistulotomy or seton placement (loose, cutting or Ksharsutra), with a filled example for a posterior trans-sphincteric fistula treated with a Ksharsutra seton.

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Blank template

Follow this order in the case sheet. Tick the options that apply and fill the blanks.

Patient and case

  1. Name / Age / Sex
  2. UHID / IP no. / Ward-Bed
  3. Date of surgery / OT no.
  4. CaseElectiveEmergency (non-elective)if emergency, state urgency and reason
  5. Timesin OT ___ anaesthesia start ___ incision ___ closure ___ out of OT ___

Team

  1. Operating surgeonname, designation
  2. Assistant(s)
  3. Supervising consultantpresent in OT / available / not applicable
  4. Steps done by the residentwhole procedure / named steps, under whose supervision
  5. Anaesthetist
  6. Scrub nurse / circulating nurse

Diagnosis and procedure

  1. Pre-operative diagnosis
  2. Post-operative diagnosis
  3. Procedure planned
  4. Procedure performedif different from plan, state why
  5. Extra procedure done and reason'none' if none. Only to save life or health if not consented

Consent and safety checks

  1. Informed consentGeneralProcedure-specificHigh-riskAnaesthesiain a language the patient understands: language ___ witness ___
  2. Site / side markedYesNot applicable
  3. WHO Surgical Safety ChecklistSign inTime outSign out
  4. Antibiotic prophylaxisdrug, dose, route, time given before incision
  5. VTE prophylaxisMechanicalPharmacologicalNot indicated

Risks to explain in the consent for this operation

  • leakage of flatus or stool (incontinence), usually minor
  • recurrence or persistent discharge
  • slow healing of the open wound
  • pain, especially at seton change or tightening
  • repeated seton changes over weeks (Ksharsutra every 2 weeks)
  • bleeding
  • need for further surgery (staged fistulotomy, other procedures)
  • specific cause found on biopsy (tuberculosis, Crohn's disease, cancer)

Pre-operative details for this operation

  1. Clinical findingsexternal opening(s): number, position, distance from anal verge; induration; Goodsall's rule prediction
  2. ImagingMRI fistulogramEndoanal ultrasoundNot donetype (intersphincteric / trans-sphincteric / suprasphincteric / extrasphincteric), extensions, abscess
  3. Recurrent / previous surgerynumber and type of previous operations
  4. Continence before surgerynormal / flatus / liquid / solid; score if used
  5. Specific causes consideredtuberculosis, Crohn's disease, diabetes; tests done
  6. Bowel preparationEnema givenNot given

Anaesthesia and position

  1. AnaesthesiaSpinalGeneralLocal block
  2. PositionLithotomyExtended lithotomyProne jack-knife

Operative findings

  1. External opening(s)position (state convention), distance from anal verge
  2. Internal openingposition; at dentate line or not; how found (probe, dye, hydrogen peroxide)
  3. Track typeIntersphinctericLow trans-sphinctericHigh trans-sphinctericSuprasphinctericExtrasphinctericHorseshoeproportion of external sphincter below the track
  4. Secondary tracks / abscess cavityNonePresent (site, size)
  5. Sphincter tone under anaesthesia and anorectal ringtrack below or above the ring

Procedure (steps)

  1. DRE and proctoscopy
  2. Dye studyDilute methylene blueMethylene blue with hydrogen peroxideNot donevia infant feeding tube in external opening
  3. Internal opening marked
  4. Track probedmalleable / grooved probe from external to internal opening, no force, no false passage
  5. Procedure chosenFistulotomy (laying open)FistulectomyLoose (draining) setonCutting setonKsharsutra setonStaged: part laid open + setonreason (track type, amount of sphincter involved)
  6. Fistulotomyincision over probe through skin, fat, anoderm and muscle below track; edges trimmed (marsupialised); track curetted
  7. Seton passedmaterial (silk, Prolene, rubber sling, Ksharsutra); passed on probe eye / hook
  8. Seton tiedLoose over muscle and skinSnug around sphincter after incising skin and anoderm
  9. Parts of track outside sphincter laid open and curettedextensions, abscess cavity
  10. Haemostasisdiathermy; wound margins marsupialised with absorbable suture if done

Closure, drains and dressing

  1. WoundLeft openMargins marsupialised
  2. Dressingpad, T-bandage
  3. Seton endslength left outside, knot position

Specimens and implants

  1. Track wall / granulation tissue for HPESentNot sent
  2. Tissue / pus for culture or TB testsSentNot sent
  3. Seton materialtype; for Ksharsutra, source / batch

End of procedure

  1. Estimated blood lossml
  2. IV fluids and blood / products givenfluids (ml); blood: type, units, bag nos.
  3. Swab, needle and instrument countCorrectIncorrect: action taken
  4. Intra-operative complications / difficultieswhat happened and what was done; 'none' if none
  5. Implant stickersNo implantAffixed in case sheet, OT register and for discharge summary
  6. Condition at end of surgery / shifted toPACUWardICU/HDU

Post-operative orders

  1. Watch for bleedingdressing soakage, pulse
  2. Urinefirst void time
  3. Sitz bathlukewarm water, twice daily or after each motion
  4. Stool softenerdrug and duration
  5. Analgesiadrug, dose, frequency
  6. Dressing / wound caredaily; keep wound edges apart so it heals from the base
  7. Seton follow-update of first change / tightening (Ksharsutra every 2 weeks)
  8. OPD reviewweekly; HPE report

Signature

  1. Name and designation of person writing note
  2. Medical Council registration no.
  3. Signature / date / time of writingwrite before the patient leaves recovery

Worked example

Fictional case: Mr. V.P., 34 years, with a discharging opening near the anus for 8 months after a drained perianal abscess. MRI fistulogram shows a posterior trans-sphincteric fistula crossing the middle of the external sphincter, internal opening in the posterior midline, no abscess.

Case details

Date: 13/05/2026. Elective. OT 2.

In OT 10:00. Spinal given 10:10. Procedure started 10:25. Procedure completed 11:05.

Surgeon: Dr A. (3rd-year resident, General Surgery). Assistant: Dr B. (1st-year resident). Consultant: Dr C., present in OT.

Anaesthetist: Dr D. Scrub nurse: Sr E.

Indication and pre-op

Indication: chronic trans-sphincteric fistula-in-ano. Not suitable for laying open because about half of the external sphincter lies below the track.

External opening at the left posterior quadrant, 4 cm from the anal verge. Continence normal before surgery.

MRI fistulogram: single trans-sphincteric track, internal opening posterior midline at the dentate line, no abscess, no secondary track.

Blood sugar normal. Chest X-ray normal.

Consent: general, procedure-specific (including repeated Ksharsutra changes, long treatment and risk of minor incontinence) and anaesthesia consent taken in Hindi from patient, wife as witness.

WHO checklist sign in and time out done. Prophylactic antibiotic as per unit policy: drug, dose and time recorded on the anaesthesia chart.

Anaesthesia and position

Spinal anaesthesia. Lithotomy position. Perianal area painted with povidone-iodine and draped. Positions below are described by quadrant.

Findings

DRE: good tone, indurated track felt posteriorly, anorectal ring intact above it. Proctoscopy: no other lesion.

Dilute methylene blue with a few drops of hydrogen peroxide injected through an infant feeding tube into the external opening. Dye seen at the internal opening in the posterior midline at the dentate line.

Track: trans-sphincteric, crossing about the middle of the external sphincter. No secondary track or abscess cavity.

Procedure

Internal opening marked with a touch of the monopolar diathermy.

Malleable probe passed gently from the external opening along the track and out through the internal opening, without force.

Ksharsutra thread loaded on the probe tip and drawn back through the track.

External part of the track outside the sphincter curetted, granulation tissue sent for HPE.

Ksharsutra tied loosely over the muscle and skin with a double knot, as a draining seton for this sitting. Extra length of thread left in the external wound.

Haemostasis with diathermy.

Closure

Wound left open. Pad and T-bandage applied. Seton knot outside the anus, ends about 3 cm long.

Specimens and implants

Specimen: curetted granulation tissue from the track in formalin, sent for HPE. No implants.

Ksharsutra: source ______, batch ______.

End of procedure

Estimated blood loss 10 ml. No transfusion.

Mop, needle and instrument count correct, confirmed by scrub nurse.

No intra-operative complications.

Shifted to post-operative ward in stable condition. Pulse 78/min, BP 120/76 mmHg.

Post-op orders

Pulse, BP half-hourly for 2 hours, then 4-hourly. Check pad for bleeding.

Note first voiding time.

Oral liquids after 4 hours, then normal diet with fibre.

Stool softener and analgesia as per ward protocol.

Sitz bath in lukewarm water twice daily from POD 1.

Discharge on POD 1. OPD review weekly. First Ksharsutra change after 15 days: new thread to be tied snugly around the muscle after incising skin and anoderm.

HPE report to be seen at first review.

Signature

Dr A., JR-3, General Surgery. Reg. no. ________. 13/05/2026, 11:20.

Must document for this operation

  • Position of the external and internal openings, and the convention used. The next surgeon changing the seton or treating a recurrence needs the exact anatomy.
  • Type of track and how much sphincter lies below it. This is the reason for choosing fistulotomy or seton, and it is checked first if incontinence follows.
  • How the internal opening was found (probe, dye, hydrogen peroxide), and that no force was used. A false internal opening made by a forced probe creates a new fistula and a medicolegal problem.
  • Continence before surgery. Without a baseline, any later leakage is blamed on the operation.
  • Seton type, material, how tied (loose or snug) and the plan for change or tightening. Seton treatment runs over weeks, and the OPD team must know what was done and when to act next.
  • Tissue sent for histopathology (HPE) and culture. Tuberculosis and Crohn's disease are known causes of fistula and change treatment.

Common mistakes in these notes

  • Writing 'fistulotomy done' without the track type or amount of sphincter divided.
  • Not recording where the internal opening was, or writing only a clock position without the patient position.
  • Leaving out continence status before surgery.
  • Not writing the date of the next seton change.
  • Not sending track tissue for histopathology (HPE).

Indian practice and paperwork

  • Ksharsutra (cotton seton coated with Ayurvedic medicines) is used in Indian general surgery departments. A randomised study at RG Kar Medical College, Kolkata (50 patients) found slower healing than open fistulotomy (mean 53 vs 35.7 days) but far less time off work (2.7 vs 15.5 days) and lower cost. (Dutta G, et al. J Nat Sci Biol Med 2015;6(2):406-10 (PubMed PMID 26283840). https://doi.org/10.4103/0976-9668.160022)

Sources

  • Singla SK, Mital K. Operative Manual of Minimally Invasive and LASER Ano-proctology. Springer; 2025, Ch 17, Fistula in Ano: Setons, Ksharsootra, draining setons, staged fistulotomy, IFTAK, rerouting, pp. 181-192.
  • Farquharson's Textbook of Operative General Surgery. 11th ed. CRC Press, Ch 15, Surgery of the anus and perineum: Anal fistulae (laying open, setons), pp. 316-320.
  • Bhat SR. SRB's Surgical Operations: Text and Atlas. Jaypee; 2014, Ch 25, Anorectal Surgeries: Fistula-in-ano (investigations, principles, fistulotomy, fistulectomy, seton technique, post-op care), pp. 1036-1041.
  • Dutta G, Bain J, Ray AK, Dey S, Das N, Das B. Comparing Ksharasutra (Ayurvedic Seton) and open fistulotomy in the management of fistula-in-ano. J Nat Sci Biol Med 2015;6(2):406-10. Retrieved via PubMed (PMID 26283840). doi.org/10.4103/0976-9668.160022

Educational template for residents. Adapt it to your institution's case-sheet format and your consultant's instructions. Patient details in the example are fictional.

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