Diverticular Disease
DEFINITION
Common outpouchings of the inner lining of the colon, associated
with several possible complications notably bleeding, infection,
perforation, stricture and fistula.
D E A B M I M
EPIDEMIOLOGY
50% by 50
80% by 80
diet related
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AETIOLOGY
Herniation of mucosa through wall
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BIOLOGICAL BEHAVIOUR
Pathophysiology
Hypertrophied sigmoid SM is probably the primary pathology.
- to rectosigmoid jx but not past.
High sigmoid pressure results
--> herniation of mucosa where blood vessels pass.
Fat creeps up the bowel wall, becomes inflamed, forms a phlegmon or
abscess, and heals with fibrosis.
--> often diverticulitis is more a 'sigmoiditis', with
inflammation in and around the bowel wall and adjacent mesenteric
fat.
May perforate, with or without fecolith impaction of a diverticulum
--> often walled off by omentum / mesentery.
--> may secondarily perf, causing pus contamination in abdomen.
Complications
Bleeding
Diverticulitis / abscess / perforation
Stricture
Fistulation
- unclear why, commonly thought to be a sequelae of an abscess but
that is not often found in association.
R-sided Tics
Tend to be Asians, younger mimics appendicitis.
Conservative Rx with Abs.
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MANIFESTATIONS
Classify.
1. Uncomplicated phlegmonous diverticulitis
2. Pericolic abscess
3. Free perf with purulant peritonitis
4. Free perf with fecal peritonitis.
Phlegmonous diverticulitis
LIF pain, peritonism and sepsis
Systemic inflammation with fever.
Hinchey
I abscess
II distant or pelvic abscess
III generalized purulent peritonitis
IV feculant peritonitis; communicates with bowel
Fistulae
Pneumaturia, fecaluria, utis / vaginal infxs, vaginal
fecal or flatus discharge
- need endoscopic evaluation to rule out tumours
Haemorrhage
Risk factors:
- hypertension, atherosclerosis
- NSAIDs
80-90% bleeds self-limiting and stop with bowel rest.
Bleeding point can be identified with colonoscopy in ~75%
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INVESTIGATIONS
Imaging
note CT can be negative in mild diverticulitis.
Colonoscopy
Must be done to confirm the diagnosis
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MANAGEMENT
Phlegmonous
Uncomplicated Divertic
Traditionally: NBM, IVF, ABs.
- but the colon contains feces anyway so it is irrational.
Feed them if no ileus. Or at least give fluids.
Oral agents are probably fine.
Mild acute diverticulitis can be managed with oral antibiotics on an
outpatient basis.
The necessity of antibiotics is questionable and has not been
validated by RCTs, which show no benefit.
- this needs to be confirmed by further RCTs before it can be
advised.
But patients who come to hospital are probably at the more severe
end of the scale
Complicated
Not settling after a couple of days --> time for a CT.
Peritonitis
and Sick
Easy decision: operate
Hinchey III,IV = Hartmann's
Laparoscopic washout and conservative Rx for Hinchey III is
controversial; good in initial trials, not currently sufficiently
established to be routine or generally advisable.
- if can get away with it, probably needn't have operated.
Severe
Attack and Stable & Abscesses
Continued conservative Rx under close observation.
Even free air, leak of contrast or abscess: not in themselves
indications for surgery if pt clinically stable.
Hinchey I & II:
Abscesses <5cm will usually settle conservatively.
Abscesses >5cm usually need drainage.
- Some surgeons then offer elective resection but controversial;
non-op therapy associated with low complication rates.
- Probably higher recurrence in Hinchey II
Contraindications to perc drainage:
- poor access route
- Hinchey III,IV
Operative
Sigmoidectomy
Low midline.
Note sigmoid may be stuck, densely adherent and difficult to work
with.
- to help differentiate from cancer: inflammation always at summit
of sigmoid loop; rectum and jx anterior to promontory are
unaffected.
Finger dissection with pinching of inflamed fat.
Remove sigmoid -- not oncological resection
Resection is from prox colon (where tineae coalesce)
- if sigmoid left behind, recurrence up to 20%; else <10%.
Stay near the bowel wall, away from ureter, gonadals
Linear stapler to bowel at both ends
- distal transection is at rectosigmoid jx.
Deal to sigmoid mesentery.
- prudent to suture-ligate inflamed vessels
Some say remove inflamed mesentery of the sigmoid as well.
What if colon grossly distended
with faeces?
Could do wash-out.
But slow and messy and bowel end discrepancy makes anastomosis
difficult.
This all counts against anastomosis.
Prefer stoma.
Mobilise Flexure?
Not needed if tension ok and good flow in marginal artery.
But mesocolon often shortened
Found incidental diverticulitis?
If uncomplicated, close and treat as usual.
Anastomose onto descending colon
with tics?
Yes, that is ok.
Massive complicated fistulating
diverticular mass?
Consider proximal diversion and drainage. Exclude cancer and come
back for definitive resection when inflammation settled.
Laparoscopy and peritoneal lavage?
New treatment principle based on observation that disease often
resolves with washout and no resection.
Peritoneal lavage with 4L saline, including when free gas, fluid
(but not feculant; ie Hinchy III not IV).
- 100 pts, prospective multicentre study; only 2 got further episode
of diverticulities in 3yr f/up
Wash out, laparoscopically suture colon hole (often none evident),
leave drains.
However local experience probably not as good as published data.
Probably not appropriate for patients with sepsis (remove the
source) or multiple comorbidities.
Probably is appropriate for a selective well patient group without
comorbidities, but that is not typically the case...
...Probably most of these patients could have been managed
conservatively anyway.
Controversies:
1. Colostomy or not in complicated diverticulosis?
- free peritonitis: Hartmann's (Hinchey III and IV) = safe exam
answer
- anything less: can anastomose.
2. Need for surgery in uncomplicated, and in complicated disease w
abscess?
- used to do it after 2nd attack, now not.
- decision analysis shows colectomy after 4th+ (vs 2nd) attack
--> reduced death, hospitalizations, and stomas.
- recurrent attacks tend to be more benign.
- individualize management is key. few are in need of
resection for persisting symptoms, fibrotic stenosis or complicating
fistula, depending on QOL.
Fistula
Pinch off, resect disease, suture bladder
Place catheter for 10d (or 5d) with cystogram prior to removal.
Divertic Bleed
Large bleed?:
- Resusc, 2xcannulae, etc
- rapid CT / angiography; must be 1 mL/min
--> 80% can be coiled successfully
- rate of colonic ischaemia <10% ("highly selective coiling") and
rebleeding <25%.
- alternatively red blood cell scall; must be 0.1 mL/min
Surgical therapy for massive lower GI is now rare
- unstable pts, those receiving >6u in 24h
- exploratory laparotomy +/- on-table enteroscopy
- if no source and appears colonic, then total colectomy with
primary anastomosis.
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REFERENCES
Cameron 10th