Colorectal Flashcards
Partial colectomy
- Mobilize colon from retroperitoneal attachments in a medial to lateral approach, identifying [named arterial pedicle] first and proceeding to white line of toldt
- Identify ureter and reflect laterally
- Ligate vessels (Take at least 2 named vessels for formal resection) at the base of the mesentery, take lots of lymph nodes (need 12 or more to stage)
→ R Hemi: ilecolic, R colic watch for duo
→ Extended R Hemi: ileocolic, R colic, middle colic
→ L Hemi: L colic, proximal sigmoidal
→ Extended L Hemi: Middle colic, L colic, proximal sigmoidal
→ Transverse (try to avoid): Middle colic
→ Sigmoid colectomy: Superior rectal artery & L colic artery are
divided at their origins, and the IMV is
divided near the inferior edge of the pancreas
Subtotal colectomy with ileorectal anastomosis
- Lithotomy position
- Transect TI with stapler, incise white line of Toldt
- Continue dissection to mobilize hepatic flexure, protect duodenum
- Enter lesser sac to mobilize splenic flexure
- Continue mobilization of L colon, identify both ureters and retract laterally before taking mesentery of colon
- Dissect distal to the rectosigmoid junction, excise surrounding mesorectum
- Transect rectum , perform end to end EEA stapled ileorectal anastomosis
- Completion proctoscopy with air leak test
End colostomy
Excise 2cm circular piece of skin in LLQ
Make cruciate incision in anterior rectus sheath, Muscle split and incise peritonuem to accomodate 2 fingers
Exteriorize colon and excise the staple line
Full thickness bites to dermis with 3-0 vicryl, no brooke
Size and apply ostomy appliance
Colostomy closure
Lower midline incision
Identify and dissect out the distal sigmoid stump
Take down the ostomy by incising 1mm of skin around stoma and separate from abdominal wall
Mobilize splenic flexure if necessary
Freshen edges by restapling
EEA stapler anastomosis: sew anvil in proximally, put stapler through anus
Appendectomy
Infraumbilical Hassan, 5mm supraumbilical, 5mm LLQ
Free appendix from surrounding structures
Make mesoappendiceal window
take appendix with gold tri-stapler that is flush with the cecum
Take mesoappendix with gold tristapler”
Low anterior resection (LAR)
- Ex lap, mobilize the rectosigmoid colon beginning at sacral promontory. Develop plane between RP & colon mesentery.
- Identify both ureters, identify IMA & perform high ligation of IMA & superior rectal artery.
- Continue dissection along pericolic gutter up the descending colon and mobilize the splenic flexure
- TME dissection posteriorly. Identify and preserve the hypogastric nerves.
- Fully mobilize rectum, identify distal & proximal points of transection, ensuring 5 cm proximal & 2 cm distal (if low rectal cancer).
- Perform tension free stapled EEA and leak test.
- Create diverting loop ileostomy.
Colorectal cancer staging
Neoadjuvant chemotherapy if Stage IV & resectable or potentially resectable
Surgical management
5 cm margins
Need at least 12 lymph nodes
Name vessels you will take
APR
- Preoperative stoma marking for end colostomy
- Medial to lateral dissection of the rectosigmoid colon beginning at sacral promontory. Develop plane between RP & colon mesentery.
- Identify both ureters, identify & perform high ligation of superior rectal artery.
- Transect proximal margin at rectosigmoid junction.
- TME dissection posteriorly. Identify and preserve the hypogastric nerves.
- Fully mobilize rectum to pelvic floor, then transition to perineal dissection, staying mindful of tumor location and ensuring adequate margins.
- Divide anococcygeal ligament until meeting up with abdominal dissection.
- Create site of end sigmoid colostomy, mature after PRS closure.
Lateral internal sphincterotomy (LIS)
- Prone position, Use anoscopy to inspect anus & pathology
- Identify intersphincteric groove
- 2 cm radial incision along intersphincteric groove in right lateral position, away from hemorrhoidal tissue, extending from dentate line to just beyond the anal verge
- Carry out the dissection to isolate internal sphincter muscle with kelly clamp
- Divide the full thickness of the internal sphincter to the level of the dentate line
- Close incision with interrupted 3-0 chromic suture
Transabdominal rectal fixation (rectopexy)
For Low risk patient’s with rectal prolapse; If chronic constipation, add LAR or sigmoid resection
- Lithotomy. Lower midline incision. Trendelendburg.
- Retract sigmoid colon superiorly & to the left.
- Mobilize sigmoid colon, preserving both ureters, gonadal vessels, presacral nerves, & superior hemorrhoidal artery, carry down to levator ani muscles.
- Reduce redundancy of sigmoid colon by pulling cephalad until bowel is straight, but not taught, over sacral promontory.
- Secure right lateral mesorectum to the sacrum using mattress 1 prolene suture x 3, ensuring rectal wall is not included.
- Ensure hemostasis & close.
Perineal rectosigmoidectomy (Altmeier Procedure)
Lithotomy
DRE
Prolapse rectum
Obtain exposure with self-retraining retractor
Inject lidocaine with epinephrine into rectal mucosa
Circumferential, full-thickness incision of rectum immediately above dentate line
Ligate & divide lateral rectal vessels within mesorectum & amputate prolapsed segment
Create coloanal anastomosis of proximal rectum/sigmoid colon to distal rectal stump, ensuring proper orientation & tension free, using absorbable sutures
Hemorrhoidal banding
Prone jacknife
Enema
DRE & anascopy
- Locate 3 hemorrhoidal bundles: right anterior, right posterior, left lateral
- Ensure acting proximal to dentate line
load the band on device, target vascular bundle just proximal the hemorrhoid and fire
Hemorrhoidectomy
- Prone jackknife, enema
- Elevate submucosal space with local anesthetic
- Incise perianal skin, minimizing anoderm excised
- Dissect hemorrhoidal tissue off internal sphincter muscle.
- Suture ligate hemorrhoidal pedicle with 3-0 Vicryl
- Close mucosal defect with 3-0 chromic, leaving edge of wound open for drainage
Do not excise all 3 columns at once due to risk of anal stenosis
Anorectal fistula management
Prone jacknife
DRE
Local anesthetic
Anoscopy
Identify external opening & internal opening using a probe abd/or hydrogen peroxide
Pass probe from external to internal opening, unroof fistula, identify any sidetracks; if >30% sphincter complex, place a seton by tying a vessel loop to probe, pulling through, and tying to itself
If intersphincteric & <30% IS involved, can perform fistulotomy (lowest risk of recurrence, but highest risk of incontinence)
Leave a drain/seton if multiple tracts
Ligation of intersphincteric fistula tract (LIFT)
- Prone jacknife, DRE, local, anoscopy
- Exchange seton for fistula probe
- Make an incision externally within the intersphincteric groove, dissect out fistula tract between external & internal sphincters so that only fistula probe is remaining.
- Suture ligation of the internal and external openings.
- Inject hydrogen peroxide before and after closing the external opening to confirm tract obliteration
- Re-approximate mucosa
Where do anorectal abscesses occur?
- Intersphincteric
- Ischiorectal - Lateral to rectal wall & space next to ischial tubercle
- Perirectal/perianal
- Supralevator
- Submucosal
- Deep postanal space - Bilaterally ends in ischiorectal fossa. Floor is anococcygeal ligament. Ceiling is levator muscle
What are the types of fistula in ano?
Starts as cryptoglandular infection in the anal canal that leads to fistula tract in anorectal space; r/o Crohns w colonoscopy
- Intersphincteric (most common)
- Transsphincteric (high >1/3 complex vs low <1/3 complex)
- Suprasphincteric (between muscles & up & over external sphincter)
- Extrasphincteric (runs over & above sphincter complex)
- Submucosal
Modified hanley procedure
Use for horseshoe abscess/post anal space (Ischiorectal fossa; floor is anococcygeal ligament; ceiling is levator muscle)
- Lithotomy, anoscopy examine anal canal
- Drain postanal space by making skin incision at point of maximal fullness in posterior midline. Divide anococcygeal ligament.
- Pass probe to identify internal opening to place a seton
- Counter incisions overlying areas of maximal fullness in bilateral ischiorectal fossa. Pass probe to posterior midline to place setons bilaterally.
- Use tonsil clamps to break up loculations and irrigate until effluent is clear
Anorectal advancement flap
- Lithotomy, anoscopy examine anal canal
- Dissect a U shaped flap with mucosa, submucosa, & portion of internal sphincter distal to internal opening of fistula.
- Extend flap proximally so that the length is 2x the base
- Ligate internal opening
- Advance mucosal flap 1 cm distal to internal fistula tract opening & suture flap to distal anal canal.
Colonoscopy pearls
- How do you prep?
- Describe procedure
- Maneuvers to advance the scope & what to do if those dont work
- When do use bx forceps, snare polypectomy, EMR, ESMD
- When to place clips & tattoo following polypectomy
Prepare: Miralax split dose prep & CLD day before, NPO after midnight. Confirm no blood thinners & allergies.
- Consent & timeout, LLD position
- DRE, insert lubricated scope and pass scope under direct visualization all the way to cecum which is identified by visualizing appendiceal orifice, ileocecal valve, & crow’s foot of cecum
- Slowly withdraw scope for at least 6 minutes
Maneuvers if unable to advance:
-Reduce loops in scope
-Manual pressure on abdomen by assistant
-Increased sedation
-Pediatric scope
-Placing on back
- If still unable, call senior partner
- If no luck, abort & perform virtual colonoscopy that day
Bx techniques
–Cold & hot bx forceps
–Cold & hot snare polypectomy → pedunculated polyps > 1 cm
–Endoscopic mucosal resection → sessile polyps > 1 cm
–Endoscopic submucosal dissection → >2 cm (dont do)
Close defect with clips if >1 cm
Tattoo all polyps greater than 1 cm; Describe location of tattoo in relation to mass
Colonoscopy interval for
1. average risk patients
2. Pts with 1st degree relative with CRC or adenomas dx before age 60, or two 1st degree relatives dx at any age
3. One 1st degree relative diagnosed with colorectal CA after age 60, or two 2nd degree relatives
4. One 2nd degree relative with colorectal CA
5. FAP
6. HNPCC
- Colonoscopy @ age 45 every 10 years or sigmoidoscopy every 5 years w/ annual FOBT
- Colonoscopy @ age 40 (or 10 years prior to dx of youngest relative) every 5 years
- Colonoscopy @ age 40 every 10 years
- Screened as Average-risk
- Sigmoidoscopy starting @ age 10-12 every year
- Colonoscopy @ age 20-25 (or 10 years prior to dx of youngest relative) every 1-2 years
Surveillance interval in personal history of adenomas
1. 1-2 tubular adenomas < 5 mm
2. ≥3 adenomas
3. Advanced adenomas (>1 cm, high grade, dysplasia, villous elements)
4. Hyperplastic polyps
1-2 tubular adenomas <5mm in size → 5 years
3 or more adenomas → 3 years
Advanced adenomas (>1cm, high grade, dysplasia or villous elements) → 3 years
Hyperplastic polyps → 10 years (considered to have normal exam)
4 criteria to manage malignant polyp endoscopically
Polyp removed in one piece
Clear margins
Well to moderately differentiated without lymphovascular or perineural invasion
≤ 2 mm into muscularis mucosa (Haggitt’s class 1, 2, 3)
Chemotherapy pearls for colon cancer
6 months FOLFOX - 5FU, (Leucovorin, Oxaloplatin) for Stage III and up (T3, T4, or N+), maybe high risk Stage II
KRAS wild-type → cetuximab (EGFR inhibitor)
Metastatic L → ertuximab
Metastatic R → avastin
Follow up after colon cancer treatment
- H&P & CEA q3m for 2 years, then q6m for total 5 years
- CT chest/abdomen/pelvis q6m for 5 years
- Colonoscopy @ 1 year, then 3 years, then no less frequently than q5 years
Early rectal cancer: Indications for transanal excision & endoscopic polypectomy
For tumors T1 (submucosa) N0 M0
Criteria for transanal excision
1. Well to moderately differentiated & no lymphovascular or perineural invasion
2. <30% circumference
3. <3 cm in size
4. >3 mm clear margins
5. Within 8 cm of anal verge
Criteria to manage malignant polyp endoscopically
1. Polyp removed in one piece
2. Clear margins
3. Well to moderately differentiated without lymphovascular or perineural invasion
4. ≤ 2 mm into muscularis mucosa (Haggitt’s class 1, 2, 3)
Early rectal cancer (limited to T1 & T2N0) not amenable to transanal/endoscopic treatment
Proctectomy with LAR vs APR. Need at least 1-2 cm margins
Measure distance of tumor from sphincter & anal verge
–Upper ⅓ rectum: 5 cm margins
–Lower ⅔ rectum: LAR with TME with 2 cm margins ideally, 1 cm may be ok; if can’t get this then need APR
–Very distal rectal cancers (extending into anal canal) or within 2 cm of anal verge → APR→ Worst rate of survival & recurrence
–Can offer neoadjuvant chemoradiation for tumors in the mid-distal rectum to avoid upstaging and avoid post-op radiation
Locally advanced rectal cancer
TNT - Total Neoadjuvant Therapy - Induction chemotherapy + long-course chemoradiotherapy or induction chemotherapy with short-course radiotherapy
Followed by transabdominal excision (LAR vs APR)
Anal SCC work up
HIV status, sexual orientation/activity, pap smears, smoking, HPV
Need anoscopy, inguinal LN exam
CT chest/abd/pelvis, pelvic MRI, colonoscopy
Anal squamous intraepithelial neoplasm classification & treatment
HPV 6 & 11 → LSIL & condyloma accuminatum
HPV 16 & 18 → High grade/HSIL/CIS/Bowen’s & squamous cell carcinoma
LSIL: Not precursor
HSIL: Precursor
Discuss options for home/topical treatments (16 weeks) vs office procedure vs operating procedure
Home tx: 5FU, imiquimod
In office tx: Electrocautery ablation, 80% trichloroacetic acid (can be painful)
Operating room: HRA-directed surgical ablation or surgical excision (no more than 50% of ATZ circumference at one visit)
Condyloma acuminata treatment
First-line patient-applied therapies include:
●Imiquimod
●Podophyllotoxin
●Sinecatechins
First-line clinician-administered therapies include:
●Cryotherapy
●Trichloroacetic acid (TCA) and bichloroacetic acid (BCA)
●Surgical removal (excision, electrosurgery, or laser)
SCC of anal CANAL management & follow up
5-FU, mitomycin C, concurrent radiation (3000 cGy)
1. Re-evaluate with physical exam 8 weeks after completion
– Complete remission → Follow with physical exam q3-6 months for 5 years & imaging q1 year for 3 years
–Persistent disease → Bx & follow up q1 month for 6 months
–Progressive disease or persistent disease at 6 months → Restage patient & consider APR
–Recurrent→ salvage APR - need wide excision w PRS
Inguinal lymph nodes + on FNA, needs extra radiation to groin vs dissection
SCC of anal MARGIN management
If any of the following present → 5FU & mitomycin based chemoradiation
1. Tumor not a discrete skin lesion that is separate from the anal canal; Question as to tumor epicenter in anus or perianal skin
2. Tumor size 2 cm or larger
3. Poorly or moderately differentiated histology
4. Sphincter function potentially compromised by
resection
5. Clinical evidence of nodal involvement
If none of the above present → WLE with 1 cm negative margins
Anal fissure management
- Determine hypertonic vs hypotonic anal sphincter (hypotonic = high risk of incontinence, consider anorectal manometry to confirm)
- Location - most commonly anterior/posterior midline; if lateral, need to rule out HIV, corhn’s, cancer - bx & colonoscopy
- Conservative tx for 4 weeks (80% heal)
→ Topical lidocaine, stool softeners, sitz baths, fiber, topical NG/nifedipine/diltiazem - If fails conservative tx, try debridement & botox injection to determine if LIS would work & see if incontinent
- Surgical treatment
–Low risk of incontinence → RIGHT lateral internal sphincterotomy (LIS)
–High risk of incontinence → fissurectomy & V-Y anal advancement flap
