1 / 47

Small Bowel

Small Bowel. Everything you ever wanted to know and more…. Basic Anatomy. 270-290 cm from pylorus to cecum Duodenum 20 cm Jejunum 100 cm Ileum 150 cm. Studying the SB. UGI and SB follow-through Enteroclysis CT Enteroscopy Push enteroscopy (up to 100 cm past LOT)

nanji
Télécharger la présentation

Small Bowel

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Small Bowel Everything you ever wanted to know and more…

  2. Basic Anatomy 270-290 cm from pylorus to cecum Duodenum 20 cm Jejunum 100 cm Ileum 150 cm

  3. Studying the SB • UGI and SB follow-through • Enteroclysis • CT • Enteroscopy • Push enteroscopy (up to 100 cm past LOT) • Double balloon enteroscopy (to TI ideally) • Capsule endoscopy (beware: obstruction)

  4. Small bowel obstruction • Etiology • Extrinsic • Adhesions (#1) • Hernias (#3) • Abscess • Mass • Intrinsic • Mass (#2) • Foreign body (bezoar, gallstone)

  5. SBO Pathophysiology • Hyperperistalsis • Bowel dilatation • Third-spacing • Decrease in mucosal blood flow • Bacterial translocation

  6. SBO Presentation • Crampy abdominal pain • Nausea • Vomiting • Obstipation PE: Vitals; Abdominal exam – scars, hernias, bowel sounds, tenderness, peritonitis; Rectal exam

  7. Imaging/Labs • AXR • +/- CT scan • BMP, CBC, possible lactate

  8. Surgical vs. Medical Treatment • Suspicion for strangulation or bowel compromise • Resuscitate and operate • Simple obstruction • Conservative management (NGT decompression, resuscitate, serial exams) • Failure or decompensation • Operate • Operation: Adhesiolysis +/- bowel resection

  9. Is the bowel viable? • Warm saline-soaked lap pads • Time and patience • Doppler • Fluorescein fluorescence • Planned second look

  10. SB Diverticular Disease • Duodenal diverticula • Asymptomatic – no treatment • Symptomatic (biliary obstruction, hemorrhage, perforation, diverticulitis, blind loop) – choledochoduodenostomy or choledochojejunostomy vs. resection or duodenal diverticulization • Jejunoileal diverticuli • Resect if symptomatic (bleeding, perf)

  11. Meckel’s Diverticulum • True diverticulum • Rule of 2’s: 2% population, symptomatic in 2%, 2 years of life, 2 feet from ICV • Rx: • Bleeding: Small bowel resection • Diverticulitis: ?SBR vs. diverticulectomy • Incidental finding in child: Diverticulectomy • Incidental finding in adult: Diverticulectomy if low risk

  12. Crohn’s Disease • Can involve GI tract from mouth to anus • 40% ileocolic, 30% SB only, 30% colon or anorectum only • Transmural inflammation, non-caseating granuloma formation • Skip lesions • Usually spares rectum • Medical and surgical treatment is palliative

  13. Crohn's Epidemiology • 3-7/100,000 • Most common in Caucasian populations • Highest incidence in N. America and Europe • Bimodal distribution (20-30s and 60s) • Etiology unclear • Increased risk of developing SB adenocarcinoma (100x)

  14. Crohn’s Presentation • Relapsing/remitting abdominal pain and diarrhea with weight loss • Extra-intestinal manifestations (30%) • Skin lesions (erythema nodosum and pyoderma gangrenosum) • Arthritis and arthralgias • Uveitis and iritis • Hepatitis and pericholangitis • Aphthous stomatitis

  15. Crohn’s Diagnosis • Barium study of small bowel (linear ulcers, transverse sinuses, and clefts) • Endoscopy (discrete ulcers,cobblestoning, skip lesions • Adjunctive labs: ASCA positive/pANCA negative

  16. Crohn’s Medical Management • Aminosalicylates (Pentasa, Asacol) • Antibiotics (Flagyl, cipro) • Corticosteroids • Immunosuppresive drugs (6-MP, aza) • Anti-TNFα (Infliximab)

  17. Crohn’s Surgery • Reserved for complications and failures of medical management (75%) • Indications • 1 – Obstruction • 2 – Fistula • 3 – Perforation/Abscess • 4 – Perianal disease • 5 – Toxic megacolon

  18. Operative Motto: “Operative treatment of a complication should be limited to that segment of bowel involved with the complication and no attempt should be made to resect more bowel even though grossly evident disease may be apparent.” -Schwartz

  19. Surgical Options • Small bowel resection • Ileocolic resection • Strictureplasty • Take mucosal bx first

  20. Small Bowel Tumors • Represent 2% of all GI malignancies • Presentation: intermittent or partial SBO, bleeding, pain, perforation, weight loss • Malignant lesions usually will cause sx – based on tumor infiltration • Benign lesions may/may not cause sx – based on intussusception • Dx: SBFT, enteroclysis, CT, enteroscopy

  21. Benign Lesions • Adenomas • Lipomas • Hemangiomas • Hamartoma Usually asymptomatic Should be excised or resected if symptomatic.

  22. Malignant Tumors • Metastatic Disease (cervix, ovaries, renal, stomach, colon pancreas, melanoma) • Adenocarcinoma • Carcinoids • Malignant GIST • Lymphoma

  23. Adenocarcinoma • 50% SB tumors • More frequently proximal SB • Treatment: Wide resection with 10-cm margins, ?adjuvant tx • Prognosis poor – usually late stage when diagnosed

  24. Carcinoids • From Kulchitsky cells – enterochromaffin cells • Produce 5-HIAA, chromogranins, neuropeptide K, substance P • 80% found within 2’ of TI • AIR: Appendix (45%), Ileum (28%), Rectum (16%) • 10% have carcinoid syndrome (diarrhea, blushing, bronchospasm, hypotension, endocardial fibrosis – R heart failure) • Metastatic carcinoid or tumors that bypass the portal system • Fibrotic, desmoplastic reaction in mesentery

  25. Carcinoid Diagnosis Dx: High index of suspicion!! • urine 5-HIAA • CT (mesenteric shortening) • SBFT • octreotide scan

  26. Carcinoids • Treatment: Segmental resection • Beware: Carcinoid crisis with general anesthesia (Rx: somatostatin, hydrocortisone, antihistamine) • prep all patient with preoperative octreotide • Adjuvant: doxo, 5-FU, streptozocin, chemoembolization bulky liver disease • Palliative for carcinoid syndrome: octreotide • Experimental: radionuclide somatostatin agonists “smart bomb”

  27. Even more SB Tumors… • Lymphoma • Ileum • Risk factors: immunodeficiency, celiac disease • Rx: Wide resection with nodes • GIST • Jejunum/ileum • Segmental resection

  28. Acute Mesenteric Ischemia • Acute-onset pain, out of proportion to exam, fever, Heme (+) stool • MI, A-fib, mural thrombus, mitral valve disease • Dx: CT scan (good for bowel, large vessels), angiogram, MRA

  29. Embolus Acute onset without antecedent sx Lodge distal to middle colic and jejunal branches of SMA Sparing of proximal jejunum and R colon Thrombus Antecedent intestinal angina Origin of vessel Entire SB and R colon affected Embolus vs. Thrombus

  30. Nonocclusive Mesenteric Ischemia (NOMI) • Optimize fluid resuscitation • Improve CO • Eliminate vasopressors • Selective vasodilatory injection (papaverine) • Bowel resection for frankly necrotic bowel

  31. Mesenteric Embolic Disease • Surgical embolectomy • Exposure of SMA • Transverse or longitudinal arteriotomy (vein patch) • 3 and 4-Fr Fogarty embolectomy

  32. Acute Mesenteric Thrombotic Disease • Bypass • Antegrade or retrograde • Conduit: autologous greater saphenous vein (acute situation) • Inflow: supraceliac aorta, infrarenal aorta, iliac artery

  33. Outcome • Perioperative mortality 62% • Multiorgan failure, ischemia/reperfusion insult • Long-term TPN 31%

  34. Chronic Mesenteric Ischemia • Chronic post-prandial abdominal pain in a vasculopath • Dx: Duplex, angiogram

  35. Management • Visceral Bypass • One or two-vessel bypass • Inflow: supraceliac, infrarenal • Conduit: Vein or PTFE/Dacron • Endovascular • PTA • *not many studies supporting management

  36. Enterocutaneous Fistula • Prevention: preoperative nutritional status, good technique, perioperative hemodynamics, bowel prep • Disability • Electrolyte imbalance • Malnutrition • Sepsis • Low-output <200cc/ 24 hr versus high >200 cc/24 hr

  37. Fistula Initial Management • Resuscitate • Imaging • Consider abx • Nutritional support • Control of fistula drainage • Skin care • Consider somatostatin

  38. Impediments to Fistula Closure • High output (>500 mL/24 hr) • Severe disruption of intestinal continuity (>50% of bowel circumference) • Active inflammatory bowel disease of bowel segment • Cancer • Radiation enteritis • Distal obstruction • Undrained abscess cavity • Foreign body in the fistula tract • Fistula tract <2.5 cm in length • Epithelialization of fistula tract

  39. Secondary Management • Fistulogram (one week later) • Define anatomy • Rule out distal obstruction • Failure of conservative management • Operate: small bowel resection

  40. Short Gut Syndrome • Less than 200 cm healthy small intestine • Downside of TPN • Liver failure • Cholelithiasis • Line sepsis • Venous thrombosis • Adaptive response: 1-2 years

  41. Short Gut Medical Therapy • Diarrhea: Immodium, lomotil, opiods • Bile salt-induced diarrhea: cholestyramine • Electrolyte losses: replete IV/PO • Hypergastrinemia: H2 blocker or PPI • Vitamin/Mineral deficiencies: Monitor and replete • Bacterial overgrowth: Flagyl, tetracycline • Enteral nutrition with supplemental TPN

  42. Short Gut Surgical Therapy • Reanastomose • Gastrostomy over jej • Intestinal valves (iatrogenic intussusception • Reversed segment • Tapering enteroplasty (Bianchi procedure) • Intestinal tranplantation

  43. The End…

More Related