1 / 40

Management of Acute Mesenteric Ischemia

Management of Acute Mesenteric Ischemia. CN Shum (2 nd Year HST) Department of Surgery Pamela Youde Nethersole Eastern Hospital. Definition of Mesenteric Ischemia. Interruption of intestinal blood flow by embolism, thrombosis, or a low-flow state. Pathophysiology.

amiel
Download Presentation

Management of Acute Mesenteric Ischemia

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. Management of Acute Mesenteric Ischemia CN Shum (2nd Year HST) Department of Surgery Pamela Youde Nethersole Eastern Hospital

  2. Definition of Mesenteric Ischemia • Interruption of intestinal blood flow by • embolism, • thrombosis, or • a low-flow state.

  3. Pathophysiology

  4. How common is Mesenteric Ischemia? • 0.1% of all hospital admissions. • Mesenteric artery stenosis is found in 17.5% of independent elderly adults. • Cappell MS, et al. Gastroenterol Clin North Am. Dec 1998;27(4):827-60, vi.  • Ha C, et al.  Am J Gastroenterol. Jun 2009;104(6):1445-51. 

  5. Acute 4 distinct mechanisms Chronic Due to long standing atherosclerosis Classification of Mesenteric Ischemia

  6. Causes of Acute Mesenteric Ischemia (AMI)

  7. Clinical presentation of Acute mesenteric Ischemia

  8. In a series of 58 patients with mesenteric ischemia due to mixed causes: abdominal pain 95% Nausea 44% vomiting 35% diarrhea 35% heart rate > 100 33% Shock 33% metabolic acidosis 33% 'blood per rectum‘ 16% Constipation 7% Park WM, et al. J. Vasc. Surg.35 (3): 445–52. Symptoms & signs

  9. Acute Mesenteric Ischemia due to embolisation • F:M=2:1 • Median age 70 • Typical presentation • Sudden onset of periumbilical pain • Followed by copious vomiting and explosive diarrhoea • Abdominal signs • Early: non-specific • Late (likely infarction): Peritonism, Blood in stool or vomitus

  10. Acute Mesenteric Ischemia due to thrombosis • Often a history of • intestinal angina • nausea • Sitophobia • significant wt loss

  11. Acute Mesenteric Ischemia due to venous thrombosis • Insidious onset over weeks • Nausea, anorexia, diarrhoea • Later clinical course • Diffuse abd pain

  12. Acute Mesenteric Ischemia due to nonocclusive disease • Occurs in patient with wide-spread vasoconstriction • Critically ill • Shock • vasopressors

  13. Diagnostic Investigations

  14. Blood tests • Elevation of • WCC • Amylase • Phosphate • Increases within 4 hours (75%) • Reference: • Can J Surg. 1979 Jan;22(1):40-5 • Metabolic acidosis

  15. Plain XRay • Non-specific dilatation of bowel • Late signs: • Thumb-printing (edematous bowel wall) • Pneumatosis intestinalis • Portal venous gas

  16. Thumb-printing

  17. Pneumatosis Intestinalis

  18. Portal Venous Gas

  19. Able to identify severe stenosis or total occlusion: Sensitivity 70-89% Specificity 92-100% Unable to detect emboli beyond the proximal main vessel NOMI Doppler USG • J Vasc Surg 14 (1991), pp. 511–518. • J Vasc Surg14 (1991), pp. 780–786.

  20. Non-invasive CTA Advantages: Better spatial resolution Faster acquisition time MRA Advantages: No radiation No need of iodinated contrast Invasive Catheter Angiography • AJR 2007; 188:452-461 • *J Gastrointest Surg. 2005 Dec;9(9):1262-74

  21. Treatment of Acute Mesenteric Ischemia …slightly varied depending of its causes

  22. Treatment in general

  23. Role of anticoagulation dependent on causes of AMI • Surgery101 (1987), pp. 383–388. • Am Surg57 (1991), pp. 573–578. • Ann Surg161 (1965), pp. 516–523.

  24. Experiences mainly on papaverine Others: tolazoline, glucagon, nitroglycerin, nitroprusside, prostaglandin E, phenoxybenzamine, and isoproterenol For NOMI Mainstay of tx Reduce mortality from 70-90% to 0-55% For Occlusive MI Adjunct Not practiced universally Am J Radiol142 (1984), pp. 555–562. Surgery82 (1977), pp. 848–855. Curr Top Surg Res3 (1971), pp. 425–433. Br J Surg77 (1990), pp. 601–603. Role of vasodilators

  25. Role of Interventional Radiology • Regan, F,et al. Am. J. Gastroenterol. 91(5):1019–1021, 1996. • Jamieson, A.C., et al. Aust. N. Z. J. Surg. 49:355–356, 1979. • Flickinger, E.J., et al. Am. J. Roentgenol. 140:771–773, 1983. • Rivitz, S.M., et al. J. Vasc. Interv. Radiol. 6(2):219–223,1995. • Rijs, J., et al. Acta. Chir. Belg. 97(5):247–249, 1997. • Train, J.S., et al. J. Vasc. Interv. Radiol. 9(3):461–464, 1998. • Poplausky, M.R., et al. Gastroenterology 110(5):1633–1635, 1996. • Walsh, R.M., et al. Surg. Endosc. 12(12):1405–1409, 1998.

  26. Case reports and small series of use of thrombolytic agents for SMA emboli

  27. Role of surgery • Allow assessment of bowel viabiltiy • Allow resection of non-viable bowel • Allow specific procedure

  28. Laparotomy findings in arterial embolism • Location of embolism • usually just distal to the middle colic artery • Sparing • proximal jejunum & distal large bowel • Next procedure: • Embolectomy

  29. Embolectomy • (A) Exposure of superior mesenteric artery by reflection of Ligament of Treitz. • (B) A transverse arteriotomy is performed transversely, proximal to the middle colic branch of the superior mesenteric artery. • (C) Embolectomy is performed with a 4-F embolectomy catheter. • (D) Artery is closed with interrupted praline suture.  Kazmers A: Ann Vasc Surg 12:191, 1998.

  30. Laparotomy findings in arterial thrombosis • Location of thrombosis • usually at the origin of SMA • No sparing • the entire small bowel and proximal large bowel appear ischemic • Next procedure • Bypass

  31. Bypass

  32. After revascularization (embolectomy or bypass) • Alert anesthetist before reperfusion • can lead to sudden physiologic and metabolic derangements, including hypotension, hyperkalemia, and profound acidosis. • Consider postrevascularization papaverine

  33. After reperfusion

  34. For non-viable looking bowel • Frankly necrotic bowel segments • resection • Marginal-viable bowel • may improve over hours • consider second-look laparotomy

  35. Prognosis Depends on time & type

  36. Mortality rates for AMI

  37. Studies showing the importance of early diagnosis of AMI on survival • a<12 hours, mortality = 0%. b<12 hours, mortality = 0%.

  38. arterial embolism 54% arterial thrombosis 77% venous thrombosis 32% non-occlusive ischemia 73% Brandt LJ, Boley SJ (2000). “AGA technical review on intestinal ischemia. American Gastrointestinal Association”. Gastroenterology118 (5): 954–68. Schoots IG, Koffeman GI, Legemate DA, Levi M, van Gulik TM (2004). "Systematic review of survival after acute mesenteric ischaemia according to disease aetiology". The British journal of surgery91 (1): 17–27. Mortality of different types of AMI

  39. Acute Mesenteric Ischemia Surgical emergency

  40. Thankyou PYNEH CN Shum

More Related