Diverticular Disease of the Colon Flashcards
Colonic diverticula , True or False explain
> not true diverticula
do not involve all layers of the bowel wall
only consist of mucosa and submucosa protruding through the muscularis propria.
what Cause it
> Intraluminal pressure cause herniation of mucosa through weak points of the muscle layer, where intramural branches of the vasa recta penetrate
Contributing factors that cause increased intraluminal pressure
- Low-fiber diet
- Small-caliber stools
- Constipation
- Consumption of red meat
- Overweight and obesity
- Physical inactivity
- Smoking
- (NSAIDs)
- positive family history
Most Common Location
In Western countries > sigmoid colon
Asia > right-sided location is common.
what causes Diverticulitis ?
combination of poorly understood factors
> bacterial stasis
the presence of a fecalith
altered microbiome
impaired mucosal barrier function
subsequent inflammatory cascade.
What causes segmental colitis associated with diverticulosis (SCAD)
> inflammatory bowel disease, suggesting an autoimmune etiology
What causes Diverticular bleeding
originates from ruptured vasa recta at either the dome or neck of the diverticulum and is arterial.
Diverticular bleeding is more likely to occur in right-sided diverticular disease, Why ?
> diverticula of the right colon typically have a wider lumen, exposing a larger mucosal surface area to luminal stress, along with a thinner colonic wall.
Uncomplicated acute diverticulitis in Sigmoid Triad
> left lower quadrant pain
fever
leukocytosis.
What are the Complications ?
- Abscesses 30%
- Fistula 14%
- Free perforation with peritonitis in 1% to 2%
- Stricture with subsequent bowel obstruction is uncommon.
How would You Diagnose ?
(CT) Abdomen/Pelvis with IV Oral Contrast
> Mainstay imaging modality for acute diverticulitis and complications. A CT of the abdomen and pelvis with intravenous and oral contrast
Patients with contrast allergy ?
> Noncontrast CT or
Alternatives > MRI or US, particularly in the pregnant patient
Ultrasonography features ?
- Hypoechoic colonic wall with a fecalith obstructing the diverticulum
> Adjacent bowel wall, and mesenteric edema, which may indicate abscess formation.
Hinchey classification
see
Uncomplicated diverticulitis Vs Complicated diverticulitis
Uncomplicated > (Stage 0 or Ia) are restricted to the colon only
Complicated > beyond the colon, involving the peritoneum and pericolic structures
Tx for Uncomplicated
-If symptoms limit oral intake > fluid resuscitation and bowel rest
-gradually advancing to a low-residue diet
-ABx > Cover gram-negative and anaerobic bacteria
> ciprofloxacin plus metronidazole
or levofloxacin plus metronidazole
If there is Escherichia coli resistance to fluoroquinolones
> amoxicillin-clavulanate monotherapy
or
trimethoprim-sulfamethoxazole plus metronidazole
Recent Studies showed What regarding Abx ?
- no difference in patient outcome comparing treatment with antibiotics versus fluid resuscitation only.
- significantly higher rate of adverse events were associated with antibiotic treatment.
- no difference in recurrence rates, complications, surgical treatment rates for the disease, and quality of life between the patient groups.
How long Abx
- a 4-day course of intravenous antibiotics was as effective as a 7-day course
When to repeat Ct ?
If a patient’s clinical status does not improve after 5 days of treatment with persistent fever, leukocytosis, and elevated acute-phase proteins (C-reactive protein) > To Rule out Abscess
What to Do after Tx, What are the Percentages of Malignancies ?
uncomplicated : (< 2%) of occult colonic malignancy
complicated : 8% to 11 %.
Colonoscopy is typically performed 6 weeks after symptom resolution
When to consider elective colon resection
-recurrent episodes affecting quality of life
-smoldering disease
-immunocompromise
What size of abscess to consider Drainage ?
antibiotics : Abscess ≤ 3 cm in size, Stable patient
percutaneous drainage : Abscesses > 3 cm or patients who do not respond to antibiotic treatment alone
Methods of percutaneous drainage ?
transabdominal
transgluteal for pelvic abscesses
transvaginal
Transrectal
Management of acute diverticulitis.
see
When to remove Drain ?
- Decreasing white blood cell and drain output to < 30 mL/ day
- Drain contrast study will show the size of the residual abscess cavity and whether there is a communication to the colon
In case of failure for Stage IB and II
surgery is indicated
> urgent abscess drainage and colectomy
with primary anastomosis and proximal diversion.
How to distinguish III and IV ?
cannot be distinguished from one another clinically
Diagnosis in Surgery
Definition of Hinchey III and IV
-III > occult colonic diverticular perforation with abscess formation and subsequent abscess rupture
-IV > free perforation of a diverticulum with peritoneal fecal contamination
higher mortality rates up to 53% were found in patients with two or more of the following risk factors:
- age > 80 years
- ASA class 4 or 5
- Elevated serum creatinine (> 1.2 mg/ dL)
- and Hypoalbuminemia (< 2.5 g/ dL).
Two types of colectomy can be performed:
(1) resection with primary anastomosis with or without proximal diversion (loop-ileostomy)
(2) resection with discontinuity and a Hartmann rectal stump and proximal end colostomy.
Why there is a decrease in hartmanns ?
-Bowel reconstruction with closure of an end colostomy after a Hartmann procedure is associated with higher morbidity compared with closure of a loop ileostomy after primary anastomosis with proximal diversion
-high-risk patients who are at substantial risk of anastomotic leakage and major complications often never undergo the second operation of colostomy closure and Hartmann takedown.
The decision on whether bowel continuity should be restored after resection based on ?
presence of shock
hemodynamic stability
immunosuppression
age
Intraoperative findings
(quality of tissue, presence of pan-abdominal inflammatory changes)
An alternative to bowel resection in case of perforated diverticulitis ?
laparoscopic lavage with drain placement
Not recommended with feculent perforation (Hinchey IV). considered in select patients with purulent peritonitis (Hinchey III)
Associated With High Recurrent Surgical Re-Intevention , and subsequent abscess formation
Diverticular Stricture
-result from chronic inflammation in patients with smoldering or recurrent diverticular disease
-underlying malignancy must always be suspected
-if colonoscopy cannot be performed preoperatively to confirm the diagnosis > oncologic resection of the diseased colonic segment with lymph node clearance
MC Diverticular Fistula
colovesical fistulas representing half of all fistulas.
Other Fistulas ?
- Colocutaneous fistulae From IR drain placement for
abscess drainage - Colovaginal fistulas
occur in women with Hx of hysterectomy - Rarely coloenteric or colouterine fistulas.
- Colonoscopy > performed to Rule out Crohns or Malignancy
In acute situation, You decided for Surgery , what to do pre op ?
- important to mark the patient for a possible stoma site in the sitting position and to avoid skin folds and creases.
- In obese individuals, the upper abdomen may provide a thinner abdominal wall, with easier stoma creation.
Common Surgical Themes
1-Work from normal to abnormal
Begin dissection proximally, freeing up retroperitoneal structures superiorly and slowly working toward the area of inflammation
2- Medial to Lateral or Lateral to Medial
3- Visualize the left ureter, Consider ureteral stents, use of indocyanine green in ureteral stents for easy intraoperative visualization.
4- If not performing an anastomosis, resect the area of perforation > no need to go down lower to the rectum itself
5- If performing an anastomosis, the distal part of the colorectal anastomosis should lie within the upper rectum.
6- If extra colonic length is needed > Mobilize the splenic flexure and the IMV or IMA may need to be divided
7- The proximal line of transection should be in soft pliable bowel
8- If there is a dense inflammatory scar around the rectum, the rectum may need to be mobilized to allow a circular stapler to pass
How to Locate the Upper Rectum
This is most easily located as the area where the colonic tenia confluence.
If an anastomosis is made in the sigmoid colon ?
there is an up to 25% recurrence rate.
Do you have to remove all Diverticular Colon ?
All of the diverticula-bearing colon does not need to be removed
In case of bowel reconstruction with primary anastomosis, How its Done ?
-end-to-end circular stapler > create a double-stapled or triple-stapled anastomosis
-If there is a lot of edema or an inability to pass a stapler transanally > hand-sewn colorectal anastomosis
Most Common Surgical Errors
- No preoperative stoma marking
- Anastomosis performed in the distal sigmoid colon
- Attempt to resect all colonic diverticula
- Very low Hartmann procedure performed, making subsequent closure more difficult
diverticular bleeding present as
- bright red blood per rectum
- hematochezia
- melena
Risk factors > NSAIDs , thrombocyte aggregation inhibitors, and anticoagulants, which is common among the elderly.
When to Transfuse Blood
-hemoglobin level of 6 g/ dL absolutely indicates the need for a blood transfusion in the acute setting.
-Patients with a history of cardiovascular disease should receive blood at an Hb level of 8 g/ dL, and a level of 10 g/ dL should be maintained.
What to do with Antiplatelets and Anticoagulation
- Aspirin > can be continued, even perioperatively
- Patients with a low thrombotic risk under warfarin therapy > reverse using prothrombin complex and vitamin K
warfarin > restarted after an interval of 7 days. - In case of high thrombotic risk (mechanical heart valve, atrial fibrillation with a prosthetic heart valve or mitral stenosis, recent venous thromboembolic event [within prior 3 months]) > pausing warfarin has to be evaluated carefully.
- heparin can be considered as a transitional solution in an emergency setting > monitoring (PTT) every 6 hours
Diagnosis ?
- colonoscopy
- CT-A
Endoscopic Strategies for Diverticular Bleeding
- Colonoscopy performed within 24 hours
- Identify source of bleeding and hemostatic intervention.
- Need bowel preparation
Endoscopic treatment :
-epinephrine injection (1: 10,000, 1– 2 mL aliquots)
-bipolar cautery
- endoclipping
- band ligation
- application of topical hemostatic agents (e.g., Hemospray).
Radiologic Strategies for Diverticular Bleeding
- detect bleeding rates of 0.3 to 0.5 mL/ min.
- For unsuccessful endoscopic evaluation, recurrent bleeding, or clinical instability
- Selective angioembolization can be performed via vasopressin infusion or coil embolization
Surgical Strategies for Diverticular Bleeding
Indications :
- Persistent or recurrent bleeding that cannot be managed via either endoscopic or angiographic
- transfusion of 6 units of blood within 24 hours to maintain a hemoglobin level
- persistent bleeding for 72 hours
- bleeding recurrence after initial treatment.
If the source of bleeding cannot be identified preoperatively,
> subtotal colectomy with end ileostomy should be considered
Or if stable Patient > ileorectal anastomosis can be considered.
Do you Consider Elective Colon Resection after Bleeding ?
-Overall Rebleeding Rate 4-42%
- Prophylactic elective resection after initial bleeding in patients at high-risk for rebleeding episodes can be considered.
