Colorectal Conference Book Review

1
Colorectal ConferenceBook Review

• H.K. Oh M.D.
• Department of Surgery

2
Topics

• Radiation Enteritis
• Meckels Diverticulum
• Acquired Diverticula
• Mesenteric Ischemia
• Obscure GI Bleeding
• Small Bowel Perforation
• Chylous Ascites
• Short Bowel Syndrome

3
Radiation Enteritis
4
Radiation EnteritisEpidemiology

• Radiation therapy
• a component of multimodality therapy for many
  intra-abdominal and pelvic cancers
• Acute radiation enteritis
• a transient condition
• in approximately 75 of patients undergoing RT
• Chronic radiation enteritis
• a inexorable condition
• in approxiamately 5 to 15 of patients undergoing
  RT

5
Radiation EnteritisPathophysiology

• Direct cellular injury Free radical generation
• Acute radiation enteritis
• Villus blunting, inflammatory cell infiltration
  in crypts
• Mucosal sloughing, ulceration, and hemorrhage
• Intensity of injury is related to radiation dose.
• Risk factors
• limited splanchnic perfusion HT, DM, CAD,
  Adhesions
• concomitant administration of chemotherapeutic
  agents
• Chronic radiation enteritis
• Progressive occlusive vasculitis that lead to
  chronic ischemia and fibrosis to all layer of the
  intestinal wall

6
Radiation EnteritisClinical Presentation

• Acute radiation enteritis
• Nausea, vomiting, diarrhea, and crampy pain
• Generally transient and subside after
  discontinuation of radiation therapy
• Chronic radiation enteritis
• Become evident within 2 yr of radiation
  administration
• Frequently affected segment terminal ileum
• Intestinal obstruction, Wt loss, intestinal
  hemorrhage, abscess, and fistula formation

7
Radiation EnteritisDiagnosis

• Review of the medical records
• Total radiation dose, fractionation, and volume
• Areas that received high dose
• Enteroclysis
• Most accurate imaging test for diagnosing chronic
  enteritis
• CT
• Neither very sensitive nor specific for chronic
  enteritis
• To rule out the presence of recurrent cancer

8
Radiation EnteritisTreatment

• Acute radiation enteritis
• Usually self-limited
• Supportive care antiemetics, parenteral
  hydration
• Chronic radiation enteritis
• Formidable challenge
• Surgery
• High morbidity and mortality rate ( 10 )
• Limited indications high grade obstruction,
  perforation, hemorrhage, abscess, and fistula
• Limited resection of diseased intestine with
  primary anastomosis between healthy bowel
  segments
• Intestinal bypass procedure alternative option

9
Meckels Diverticulum
10
Meckels DiverticulumEpidemiology

• The most prevalent congenital GI anomaly (2)
• 3 2 male to female prevalence ratio
• True diverticula contains all layers
• Usually found in the ileum within 100cm of IC
  valve
• Heterotropic mucosa (60)
• Gastric mucosa, pancreatic acini, Brunners
  glands
• Rule of Two
• 2 1 Female predominance
• Location 2 feet proximal to the IC valve
• Symptomatic age under 2 yr

11
Meckels DiverticulumPathophysiology

• Failure or incomplete omphalomesenteric(vitelline)
  duct obliteration during the 8th wk of
  gestation
• Bleeding
• Acid producing heterotropic gastic mucosa -gt
  adjacent ileal mucosal ulceration
• Intestinal obstruction
• Volvulus of the intestine around the fibrous band
  attaching the diverticulum to the umblicus
• Entrapment of intestine by a mesodiverticular
  band
• Intussusception
• Stricture secondary to chronic diverticulitis

12
Meckels DiverticulumClinical Presentation

• Lifetime complication rate 4
• uncomplicated condition -gt asymptomatic
• Bleeding
• frequent complication in young age
• Intestinal obstruction
• common in adult
• Diverticulitis
• indistinguishable condition from acute
  appendicitis
• Neoplasm
• most commonly carcinoid tumors

13
Meckels DiverticulumDiagnosis

• Incidental discovery on radiography, during
  endoscopy, or at the time of surgery
• CT low sensitivity
• Enteroclysis usually not applicable during
  acute presentation
• Radionuclide scans ectopic gastric mucosa,
  active bleeding
• Angiography bleeding site localization

14
Meckels DiverticulumDiagnosis
15
Meckels DiverticulumTherapy

• Management of incidentally found Meckels
  diverticula
• Controversial
• Recently prophylactic diverticulectomy
• Surgical treatment of symptomatic disease
• Diverticulectomy with removal of associated band
• Combined segmental ileal resection bleeding,
  tumor

16
Acquired Diverticula
17
Acquired DiverticulaEpidemiology

• False diverticula consist of mucosa and
  submucosa
• Duodenal diverticula
• tend to be located adjacent to the ampulla -gt
  periampullary, juxtapapillary, or peri-Vaterian
  diverticula
• usually medial wall of the duodenum
• prevalence increased with age
• UGIS 0.16 6 , ERCP 5 27
• Jejunoileal diverticula
• jejunum (80), ileum (15), both (5)
• prevalence 1 5
• Complication rate 6 10

18
Acquired DiverticulaPathophysiology

• Acquired abnormality of intestinal smooth muscle
  or dysregulated motility -gt herniation of musoca
  and submucosa through weakened areas of
  muscularis
• Bacterial overgrowth, Vit B12 deficiency,
  megaloblastic anemia, malabsorbtion, steatorrhea
• Periampullary diverticula
• distension obstructive jaundice or pancreatitis
• Jejunoileal diverticula
• intussusception or compression intestinal
  obstruction

19
Acquired DiverticulaDiagnosis

• USG, CT
• Duodenal diverticula may mistaken for pancreatic
  pseudocysts, fluid collections, biliary cysts and
  periampullary neoplasm.
• Endoscopy
• Lesion can be missed on forward viewing
• UGIS
• Best diagnostic tool for duodenal diverticula
• Enteroclysis
• The most sensitive test for detecting jejunoileal
  diverticula

20
Acquired DiverticulaTherapy

• Asymptomatic should be left alone
• Bacterial overgrowth antibiotics
• Bleeding, diverticulitis, and obstruction
• Jejunoileal diverticula segmental resection
• Lateral duodenal diverticula diverticulectomy
  alone
• Medial duodenal diverticula
• Should be managed nonoperatively if possible
• Bleeding lateral duodenotomy and oversewing of
  the bleeding vessel
• Perforation wide drainage rather than complex
  surgery

21
Mesenteric Ischemia
22
Mesenteric IschemiaPathophysiology

• Acute Mesenteric Ischemia
• Arterial Embolus
• most common cause ( gt 50), cardiac disease
  history
• usually distal artery
• Arterial Thrombosis
• acute thrombosis on preexisting atherosclerotic
  changes
• usually proximal artery
• Vasospasm (Non-Occlusive Mesenteric Ischemia
  NOMI)
• Venous Thrombosis usually SMV
• Chronic Mesenteric Ischemia
• Arterial Ischemia main splanchnic arteries
• Venous Thrombosis

23
Mesenteric IschemiaClinical Presentation

• Acute Mesenteric Ischemia
• Severe abdominal pain out of proportion to the
  degree of tenderness
• Colicky and most severe in the mid abdomen
• Full-thickness infarction (within 6hr)
• distension, peritonitis, bloody stool
• Chronic Mesenteric Ischemia
• Insiduous course, collateral circulation
• Postprandial abdominal pain Food Fear , Wt
  loss
• Chronic venous thrombosis portal hypertension

24
Mesenteric IschemiaClinical Presentation
25
Mesenteric IschemiaDiagnosis

• Acute Mesenteric Ischemia
• Lab abnormalities late findings
• Peritoneal Irritation Sign gt Prompt Laparotomy
• CT initial imaging test
• Angiography the most reliable method
• especially NOMI
• invasive, time-consuming, and costly
• Chronic Mesenteric Ischemia
• Angiography gold standard
• CT angiography noninvasive alternative
• Duplex USG screening test

26
Mesenteric IschemiaDiagnosis
SMA occlusion
SMV thrombosis
27
Mesenteric IschemiaTherapy

• Acute Mesenteric Ischemia
• Considerations sign of peritonitis, general
  condition, and specific vascular lesion
• Arterial occlusion
• Surgical revascularization thrombectomy,
  mesenteric bypass
• Thrombolysis alternative therapeutic option
  (within 12hr)
• NOMI selective infusion of vasodilator
  (papaverine)
• Venous thrombosis anticoagulation till 1yr
• Chronic Mesenteric Ischemia
• Surgical revascularization bypass graft
  endarterectomy
• Percutaneous transluminal mesenteric angioplasty

28
Mesenteric IschemiaTherapy
Percutaneous Angiographic Intervention
29
Mesenteric IschemiaTherapy
Thromboembolectomy
Bypass Graft
30
Management Algorithm
31
Mesenteric IschemiaOutcomes

• Acute Mesenteric Ischemia
• Mortality
• Arterial disease 59 93
• Venous disease 20 50
• Recurrence
• No anticoagulation -gt 30
• especially within 30 days of presentation )
• Chronic Mesenteric Ischemia
• Perioperative mortality 0 16
• Recurrence less than 10

32
Short Bowel Syndrome
33
Short Bowel SyndromeEpidemiology

• Definition
• The presence of less than 200cm of residual small
  bowel in adult patients
• Insufficient intestinal absorptive capacity to
  result in the clinical menifestations of
  diarrhea, dehydration, malnutrition
• Etiology
• Adult mesenteric ischemia, malignancy, and CD
• Pediatric intestinal atresia, volvulus, and NEC

34
Short Bowel SyndromePathophysiology

• Residual bowel length
• When greater than 50 80 resection
• Enteral Autonomy
• Intact colon
• Capacity to absorb large fluid, electrolyte, and
  short chain fatty acid
• Intact IC valve
• Prolong contact time between nutrients and small
  bowel
• Healthy residual small bowel
• Ileum bile salt and Vit B12 absorption

35
Short Bowel SyndromeMedical Therapy

• Initial Period
• Management of primary condition
• Repletion of fluid and electrolyte loss
• Total parenteral nutrition
• Gradually introduced enteral nutrition
• High dose H2 receptor blocker, PPI
• Antimotility agent, Octretide
• Adaptation Period (generally postop 1 2yr)
• Attempt to wean from TPN
• TPN and enteral nutritional titration

36
Short Bowel SyndromeSurgical Therapy

• Restoration of stoma
• Slowing intestinal transit time
• Segmental reversal of small bowel
• Interposition of colon segment between small
  bowel segments
• Construction of small intestinal valves
• Electrical pacing of the small intestine
• Lengthening procedure
• Longitudinal intestinal lengthening and tailoring
  ( LILT )
• Serial transeverse enteroplasty procedure ( STEP
  )

37
Short Bowel SyndromeSurgical Therapy
L I L T ( Bianchi in 1980 )
38
Short Bowel SyndromeSurgical Therapy
S T E P ( Kim et al 2003 )
39
Short Bowel SyndromeIntestinal Transplantation

• The Currently Accepted Indications
• The presence of life-threatening complication
  related to gut failure and/or long term TPN
• Impending or overt liver failure
• Thrombosis of major central veins
• Frequent episode of catheter related sepsis
• Frequent episode of severe dehydration
• Method
• Isolated intestinal TPL no other organ failure
• Combined intestine/liver TPL
• Multivisceral TPL

40
Short Bowel SyndromeIntestinal Transplantation
41
Miscellaneous Conditions

• Chylous Ascites
• Small Bowel Perforation
• Obscure GI Bleeding

42
Chylous Ascites

• Definition TG-rich peritoneal fluid with a
  milky or creamy appearance
• Etiology
• Abdominal malignancy, Cirrhosis, Infection(Tb,
  Filariasis)
• Postop Complication
• Diagnosis
• Paracentesis TG level gt 110 mg/dL
• CT original patholgy, extent, and localization
• Lymphangiography, Lymphoscintigraphy
• Management
• High protein, low-fat diet with medium chain TG
• NPO, TPN, Octreotide, and Paracentesis
• Surgical correction repair with fine
  nonabsorbable suture

43
Small Bowel Perforation

• Etiology
• Iatrogenic injury endoscopy related (m/c)
• infection, CD, Ischemia, Drugs, Radiation induced
  injury
• Menifestation
• Abdominal pain, Tenderness, Distension, Fever,
  Tachycardia
• Diagnosis
• CT the most sensitive test
• Treatment
• Retroperitoneal perforation selective
  nonoperative care
• Intraperitoneal perforation prompt surgery

44
Obscure GI Bleeding

• Terminology
• Obscure GI bleeding no identifed source by
  routine endoscope
• Overt GI bleeding presence of hematemesis,
  melena, or hematochezia
• Occult GI bleeding absence of overt bleeding
  with laboratory detected bleeding
• Etiology
• Angiodysplasia, Neoplasm, CD, Infection, Drug,
  Ischemia
• Diagnosis
• Endoscopy Push enteroscopy, Sonde enteroscopy,
  Intraoperative enteroscopy, Capsule enteroscopy
• Angiography reveal angiodysplasia and vascular
  tumor
• RBC scanning

45
(No Transcript)
46
Thank You For Your Attentions