Download - Rakesh benign-anorectal-
27/06/13 Dept. of Surgery
Benign Anorectal: Abscess and FistulaRakesh Kumar Gupta, MS
Benign Anorectal: Abscess and Fistula
Anorectal abscess and fistula-in-ano represent different stages of the same disease
the abscess represents the acute inflammatory event
the fistula represents the chronic process
Benign Anorectal: Abscess and Fistula
Diagnosis and treatment requires in-depth understanding of anorectal anatomy and spaces
Anorectal SuppurationEpidemiology
Anorectal abscesses (“Acute phase”)
100,000 cases per year
Age range 20-60, 2:1 ratio M:F
30% recurrence rate*
Anorectal fistula (“Chronic phase”)
25-40% of abscesses lead to fistula**
10-20% recurrence rate
* Shrum RC. Dis Colon Rectum 1959; 2:469–472, **Shouler PJ et al . Int J Colorect Did 1986,1:113-5
80% are submucosal, 8% extend to internal sphincter, 8% to the conjoined longitudinal muscle, 2% intersphincteric, 1% penetrate internal sphincter
At the dentate line, the ducts of the anal glands empty into anal crypts
90% of anorectal abscess result from crytogladular infection
Parks cryptoglandular theory - obstruction of anal glands leads to stasis and infection
Abscess
Classified by location:
Perianal (50%),
Intersphincteric (30%),
Ischioanal (15%),
Supralevator (5%)
Classification of Anorectal Abscesses
SupralevatorSpace
IntersphinctericSpace
Ischioanal Space
HORSESHOE ABSCESS
Abscess - Etiology
Nonspecific cryptoglandular (90%)
Specific causes:
Specific infection, ie TB, actinomycosis, lymphogranuloma venereum,
Inflammatory bowel disease,
Trauma or foreign body
Surgery (episiotomy, hemorrhoidectomy, prostatectomy),
Malignancy - carcinoma, lymphoma, radiation-related
Pain Severe, constant pain, worse with movement/pressure (sneezing, coughing, bearing down),better with drainage
Swelling,
Fever chills hallmark symptoms
supralevator abscess may have gluteal pain
rectal pain with urinary symptoms (ie. Constipation, Urinary retention) - possibly indicate intersphincteric or supralevator abscess
Anorectal AbscessClinical Presentation
Anorectal AbscessClinical Presentation
• Exam
– Induration, fluctuance, erythema, warmth, purulent drainage
– DRE
Abscess - Treatment
Exam under anesthesia for pain out of proportion to exam
Incision and drainage - trim edges to prevent coaptation
I&D of supralevator abscess:
depends on location - intersphincteric origin then divide internal sphincter and drain into rectum; if arises from ischianal abscess can be drained through perineal skin
Anorectal AbscessTreatment
I&D- cruciate or elliptical incision
Abscess - Treatment
Catheter drainage: stab incision to drain pus, mushroom catheter in cavity to drain pus
make stab incision as close as possible to anus
size and length of catheter should correspond to abscess cavity
Short distance from anus – feel for soft spotPlace drain and trim – avoids packingFollow up in 7-10 days to remove drain
Catheter Types
Pester catheter
Solid mushroom top so stays in
Less tissue ingrowth
Malecot
Allows tissue ingrowth
More painful to remove
Abscess - Treatment
Primary fistulotomy
may be easier to identify tract
eliminates source of infection
decreases recurrence/need for reoperation
Downsides: false passage formation with acute inflammation, 30-50% of those with abscess likely won’t develop a fistula, need for anesthesia vs. local for I & D
Incision and drainage of perianal abscess with or without treatment of anal fistula. Cochrane Database Syst Rev. 2010 Jul 7;(7):CD006827.
CONCLUSIONS: The published evidence shows fistula surgery with abscess drainage
Significantly reduces recurrence or persistence of abscess/fistula, or the need for repeat surgery.
No statistically significant evidence of incontinence following fistula surgery with abscess drainage.
Intervention may be recommended in carefully selected patients.
Abscess - Antibiotics
Little or no role
Antibiotics? Culture?
Indications:
Immunosuppression
Valvular heart dz
Prosthetic devices
Sepsis or Extensive cellulitis
Crohn’s dz
Sitz Baths
Abscess - Complications
Recurrence
recurrence in as many as 89% of pts
Extra-anal causes
should be evaluated for recurrent disease (hidradenitis suppurativa, Crohn’s)
Incontinence
iatrogenic (superficial external sphincter), inappropriate wound care (excessive scarring from prolonged packing)
Abscess - Complications
Can result in necrotizing anorectal infection (rare)
Resuscitation, IV abx, wide debridement to healthy tissue
Need for colostomy debatable - recommended if sphincter muscle is grossly infected, immunocompromised, rectal or colonic involvement/perforation
Reexamination under anesthesia
HBO - 100% O2 at 3atm over 2 hrs - promote leukocyte phagocytic function and fibroblast proliferation
Caution – Necrotizing Fasciitis
Anal Infection and Hematologic Diseases
Anorectal suppuration with acute leukemia with mortality 45-78%
Neutrophil count <500 with 11% incidence of anorectal abscess
Most important prognostic factor - # days of neutropenia
Presenting symptoms: fever, pain, urinary retention
Antibiotics vs I & D if fluctuance, sepsis, or progression of soft tissue infection after antibiotics trial
Anal Infection & HIV
HIV+ pts have increased risk of perianal sepsis
Can be associated with in situ neoplasia
Surgery + antibiotics 2/2 immunosuppression
make incison site small bc pts at risk for poor wound healing
Fistula-in-ano
Abnormal communication between any two epithelium-lined surfaces
Parks classification:
Classification
Intersphincteric fistula
Intersphincteric Fistula-in-ano
Most common type of fistula - 70%
Results from perianal abscess
Variations:
simple low tract
high tract with rectal opening or blind tract
extrarectal extension
pelvic disease tracking
Transsphincteric fistula
Transsphincteric Fistula
Approx 23% fistulas
Results from ischioanal absecesses
Rectovaginal fistula is a form of transsphincteric fistula
Operative mgt with setons if sphincter preservation in question
Suprasphincteric fistula
Suprasphincteric Fistula
5% of fistulas
Result from supralevator abscesses
Tract arises from intersphincteric abscess, travels above puborectalis, then downward lateral to external sphincters in ischioanal space
Extrasphincteric fistula
Extrasphincteric Fistula
2% of fistulas - rarest form
From rectum above the levators, through them, to the perianal skin
Trauma, foreign body, Crohn’s carcinoma
Most common cause is iatrogenic from probing during fistulotomy surgery
Evaluation of Anal Fistula
An accurate preoperative assessment of the anatomy of an anal fistula is very important.
Five essential points of a clinical examination of an anal fistula :
(1) location of the internal opening.
(2) location of the external opening.
(3) location of the primary track .
(4) location of any secondary track.
(5) determination of the presence or absence of underlying disease .
Fistula-in-ano: Physical Examination Goodsall’s rule:
transverse line across the perineum -
posterior external openings have internal openings in the posterior midline
anterior external openings have tract radially toward the nearest crypt
greater distance from anal margin with more variability
more accurate rule for posterior fistulas
Fistula Description Clock description
Does the anus tell time?
Relies on description of patient’s position: supine, lateral, prone and relative landmarks
Anatomic description: more consistent
Pubic bone defines anterior
Coccyx define posterior
Right and left
*If terms be incorrect, then statements do not accord with facts; and when statements and facts do not accord, then business is not properly executed.”
Tailbone
Right anterior
Right posterior
Left anterior
Left posterior
Right Left
Pubic bone
High Fistulas Have High Internal Openings (opening of the duct at the crypt, is always at the level of the pectinate line)
Internal Opening is Not Always Present
Fistulas with Multiple Openings are Tuberculus in Origin
Every Fistula Requires an MRI/Endoanal USG
Which is the Best Surgery for Fistula in Ano?
Controversies in Fistula in Ano
Mutiple external openings over the right buttock—non tuberculus
Investigations Additional tools available in case of difficulty.
Do not replace a good clinical examination to diagnose the type & extent of fistula.
Not necessary to investigate every case of fistula even the complex ones can be diagnosed fairly accurately by a good clinical examination.
MRI & Endoanal ultrasound both give comparable
Delineating the tracts by intra-operative dye study may be more helpful than the above investigations.
Fistulograms have a very limited role in the diagnosis of fistula in ano
Anorectal FistulaDiagnosis
MRI for fistula-in-ano
HALLIGAN Radiology 2006Abscesses &Extensions
Contralateral disease
TREATMENT
The objective is to cure with lowest possible recurrence rate and minimal, if any, alteration in continence, shortest period.
The principles are:
Control sepsis
EUA
Laying open abscesses and secondary tracts
Adequate drainage – seton insertion
.
Define anatomy
Openings and tracts
Internal and External (Identification of the primary opening)
Single –v- multiple
Extensions / Horseshoe (Side tracts should be sought )
Relation to sphincter complex
High –v- Low (Relationship to puborectalis)
Exclude co-existent disease
Fistula-in-ano: Treatment
Eliminate fistula,
Prevent recurrence,
Preserve sphincter function
Fistula-in-ano: Treatment
Identification of internal opening
passage of probe
injection of dye, methylene blue, or hydrogen peroxide
following granulation in fistula tract
noting puckering of crypt with traction on fistula tract
Fistulotomy/fistulectomy
Lay-open technique (fistulotomy) : identification of tract with unroofing tract, useful for 85-95% of primary fistulae .
Appropriate for simple interspincteric and low transsphincteric
Curettage is performed to remove granulation tissue.
Marsupialization of the edges to improve healing times.
Surgical Options – Fistulotomy
Fistula tract identified with probe
Extent of external sphincter involvement assessed
Tract and muscle divided
Secondary tracts laid open
+/- marsupialisation wound
Fistula in ano
Fistula in ano
Surgical Options – Fistulectomy
• Core out tract
• Direct visualisation of secondary tracts
• Sphincter repair +/- advancement flap
Fistula-in-ano: Operative Management Seton - placement of non-absorbable suture material in
fistula tract
Indications for setons:
Promote fibrosis around fistula tract that encircles entire sphincter mechanism
Mark the site of fistula in massive anorectal sepsis
Anterior high transsphincteric fistulas in women
HIV pts with poor wound healing and high transsphincteric fistulas
Crohn’s
Any time continence is questioned
Surgical Options – Cutting Seton
Lay open external tract
Draining seton replaced with cutting seton
1/0 Prolene suture
Tied tight around sphincter complex
Simultaneous slow cutting and repair of sphincter
May require re-tightening
Setons in the Management of Difficult Fistulas
Fistula-in-ano: Operative Management
High-transphincteric fistulas can be treated with combination lay-open technique and seton placement - division of internal sphincter to level of external opening and then seton placement
Cutting setons can convert high fistulas to low fistulas
Second-stage fistulotomy ~ 8 wks later
Fistula-in-ano: Operative Management
Suprasphincteric fistula - tract involves external sphincter and puborectalis -
can manage with division of internal sphincter and superficial external sphincter with seton around remaining ES
or internal sphincterotomy, seton, opening of fistula tracts without division of external sphincter
Fistula-in-ano: Operative Management
Anorectal Advancement Flap
internal opening closed with absorbable suture, full-thickness flap of rectal mucosa/submucosa/IAS raised - adv 1 cm beyond internal opening
base of the flap should be twice the width of the apex
pros: reduction in healing time, reduced pain, little potential damage to sphincters, lack of deformity to anal canal
poor outcomes in Crohn’s, pts on steroids, smokers, o/w success reported in up to 90% of pts
Advancement Flaps
Endorectal Fistula tract probed
Flap raised
Mucosa + Int. Sphincter
Internal opening excised/closed
Flap advanced & sutured
Advancement Flap
Anodermal Fistula tract probed
Flap raised
Anodermal
Flap advanced & sutures
External defect closed
Fistula-in-ano: Operative Management
Fibrin Glue - used in conjuntion with AAF or alone
technique: internal and external openings identified, tract curetted, fistula tract injected through connector from external opening until glue visible in internal opening, slowly withdrawn
can be repeated several times without compromising continence
Fistula-in-ano: Operative Management
Fibrin Glue - Followup:
short-term follow-up with good success 70-80%
longer follow-up with success falling to 60% and even 14% in pts with complex anal fistulas
Fistula Plug
Fistula Plug
Fistula-in-ano: Operative Management
Bioprosthetic fistula plug made from surgisis
Technique - identification of internal and external opening with placement of plug over probe using suture similar to seton placement
Plug secured at primary opening using absorbable suture
Fistula-in-ano: Operative Management
Technique works best with long tracts without active inflammation or sepsis
Short-term follow up (3months) with higher success rate for Crohn’s fistulas when compared to fibrin glue
Long-term follow up - high failure rate
LIFT Procedure
Ligation of Intersphincteric
Fistula Tract Transsphincteric fistula
Draining seton – 6 weeks
Tract prepared with fistula brush
Debrides
De-epithelializes
PROS CONSCutting Seton Simple
CheapRepeat EUARecurrence 0 – 8%Incontinence• minor 34 – 63%• major 2 – 26%
Fistulotomy SimpleCheap
Recurrence 2 – 9%Incontinence 50%
Advancement Flap Can be difficult?Preserves sphincter
Recurrence 25 – 50%Incontinence 30 – 35%
Fistula Plug SimplePreserves sphincter
Plug expensive ~£400Recurrence 20 – 85%Continence preserved
LIFT SimplePreserves sphincter
Recurrence 15 - 40%Continence preserved
Crohn’s and Anal Fistulas
The most common perianal manifestation and occur in 6-34% Crohn’s pts - pts with colonic Crohn’s with higher incidence, rectal Crohn’s with 100% fistula formation
Conservative approach to treatment as 38% heal without surgery
Crohn’s and Anal Fistulas
Medications for treatment: cipro/flagyl, immunomodulators (steroids, 6MP, azathioprine, infliximab)
6-MP and azathioprine only effective in 1/3 pts with fistulizing Crohn’s
Infliximab associated with 62% reduction
Combination 6MP and infliximab may prolong effect of treatment
Selective seton placement with infliximab + maintenance med with healing in 67%
Crohn’s and Anal Fistulas
Operative intervention: seton placement, rectal advancement flap if rectal-sparing, poss fibrin glue/plug
Avoid cutting sphincter - incontinence reported in pts with Crohn’s proctitis even without anal surgery
ACPGBI FIAT Trial
Fistula Plug Insertion
Surgeon’s Preference
EUA: transsphincteric fistula ≥ 1/3 of
sphincter complex Insertion of draining
seton
RANDOMISE
MRI fistulography
Advancement Flap
Cutting Seton Fistulotomy LIFT
ACPGB&I FIATPrimary end-points
Faecal incontinence QoL
Generic QoL
Secondary end-points
Healing – 12 months
Complications
Faecal incontinence
Re-interventions
Health resource utilisation
Cost effectiveness
Patient identification
EUA & draining seton
Eligibility & Consent
Randomisation1:1 plug –v- surgeon’s
preference
6-week FU
6-monthFU
12-month FU+ MRI scan
Surgisis® fistula plug
Surgeon’s preference(fistulotomy, seton,
advancement flap, LIFT)
MRI scan
Surgery(6-weeks post seton
insertion)
Join the FIAT Trial!