Transcript ASE_Materials/mesentericischemia.pps

Acute Mesenteric Ischemia
Scott Q. Nguyen, M.D.
Celia M. Divino, M.D.
Mount Sinai School of Medicine
Department of Surgery
Mrs. Mitty
• An 83 year-old woman is brought to the
ER by ambulance from her nursing home
w/ a 4 hour history of severe diffuse
abdominal pain and distention.
History
What other points of the history do
you want to know?
History, Mrs. Mitty
Consider the Following
• Characterization of
symptoms
• Temporal sequence
• Alleviating /
Exacerbating factors:
• Pertinent PMH, ROS,
MEDS.
• Associated signs and
symptoms
• Relevant family hx.
History, Mrs. Mitty
• Characterization of Symptoms:
 Sudden onset diffuse abdominal pain and distention
4 hours ago.
 Pain not localized to any quadrant.
• Alleviating / Exacerbating factors:
 Pain is excruciating, it’s the worse she’s ever experienced
 Nothing alleviates it
• Associated signs/symptoms:
 She vomits 1L of feculent emesis on arrival to ER.
 Last BM 2 hours ago, loose
Other History
• PMH
 Atrial Fibrillation - dx’d 1 month ago,
anticoagulation contraindicated with history of
massive GI bleed
 CHF, CAD, DM
• PSH
 Cholecystectomy, left hemicolectomy for
diverticular disease
• MEDS
 digoxin, metoprolol, insulin
Other History
•
Social History
 Occasional wine,
 50 pack-yr smoker, quit 2 yrs ago
• Family History
 Patient unable to give
What is your Differential
Diagnosis?
Differential Diagnosis
Based on History and Presentation
• Small Bowel Obstruction
• Acute Mesenteric
Ischemia
• Perforated Diverticulitis
• Ischemic Colitis
• Perforated Peptic Ulcer
Disease
• Acute Pancreatitis
• Acute Cholecystitis
• Gastroenteritis
• Acute Appendicitis
Physical Examination
What would you look for?
Physical Examination
• Vital Signs: T = 38.5, P = 103, BP = 140/85, RR = 28
• Appearance: thin , in severe distress, legs pulled up to chest,
moaning
• Heart: irregularly irregular
• Lungs: mild rales at bases
• Abdomen: decreased BS, very distended, mildly tender
diffusely, no guarding/rebound tenderness, no hernias
• Rectal: loose stool in vault, streaked w/ fresh blood
Remaining Examination findings non-contributory
Would you like to revise your
Differential Diagnosis?
Laboratory
What would you obtain?
Labs ordered, Mrs. Mitty
14
405
42
133
101
30
4.9
19
1.2
85 PMN’s 22 Bands
•
•
•
•
•
LFTs - WNL
Amylase/Lipase - 89/95
PT/PTT - 13.0/33.0
ABG - 7.31/30/69/16
Lactate 7.9
240
Lab Results, Discussion
• Leukocytosis - acute process, possibly infectious
• Electrolytes - elevated BUN indicating dehydration or
3rd spacing.
• Anion gap acidosis - intravascular depletion,
Metabolic acidosis (lactic acidosis)
• Coags –abnormal coags may reflect sepsis. Pt. not on
anticoagulation for Afib.
• Normal LFTs/ pancreatic enzymes - no signs of
hepatic/pancreatic insult
Interventions at this point?
Consider the following Interventions
• Admit to the hospital/ICU
• Aggressive resuscitation
• Start IV with isotonic crystalloid solution
( NS or LR)
• Insert Foley catheter
• Monitor response to resuscitation
• Administer broad spectrum antibiotics
• Likely intra-abdominal septic process
Studies
What further studies would you want
at this time?
Studies, Mrs. Mitty
• Abdominal X-rays
• Flat / Upright
• Acute Abdominal Series (may include chest at some
institutions)
Studies – Results
• Plain abdominal films
 Diffuse dilation of small bowel w/ air fluid
levels on upright view. Some air in Left
colon and Rectum. NO free air
What is the differential
diagnosis at this point?
Revised Differential Diagnosis
1) Acute Mesenteric Ischemia
2) Strangulated small bowel obstruction
3) Diverticulitis w/ contained perforation?
What next?
What next?
• Mesenteric Angiogram or CT
Angiogram
Discussion
• With the sudden onset of symptoms, h/o Afib,
and “pain out of proportion to physical exam,”
acute mesenteric ischemia should be high on
the Differential Diagnosis
• A mesenteric angiogram will allow
visualization of the visceral vessels (celiac,
SMA, IMA)
Mesenteric Angiogram
Note complete lack of contrast in mesenteric vessels in AP view (left). The
occluded origins of the celiac axis and superior mesenteric artery are
demonstrated in the Lateral view (right).
CT Angiogram
Note complete occlusion and lack of IV contrast filling the superior
mesenteric artery from its origin from the aorta (Arrows).
Other studies
CT angiogram / MR angiogram
• sensitivity 75%, specificity 100% for emboli
• additionally can detect thickened, distended
bowel loops
• more sensitive for Mesenteric Venous
Thrombosis
Management
What should be done next?
Management
• Pre-operative preparation
• Assure adequate resuscitation
• Monitoring
• Foley Catheter
• Urgent exploration
• Surgical embolectomy
• Assess bowel viability
Management
• Pre-operative preparation
•
•
Assure adequate resuscitation
Monitoring
• Non-invasive: EKG, BP, Pulse Oximetry, foley catheter
• Consider invasive monitoring: Central venous catheter,
PA Catheter ? Arterial line?
• Operative Technique/ Urgent exploration
•
•
•
•
Midline Laparotomy
Relevant Anatomy
Surgical Embolectomy
Assess bowel viability
Surgical Embolectomy
• Pack bowel to Right,
Expose SMA
• Arteriotomy
• Pass balloon embolectomy
catheter
• Assess bowel viability
• Resect if necessary
Necrotic bowel from
mesenteric ischemia.
Discussion
Acute mesenteric ischemia is a vascular emergency
with overall mortality 60-80%. There are four main
pathophysiologic processes which have the same
common endpoint, bowel necrosis, abdominal sepsis,
and death. Mesenteric arterial anatomy is notable for
rich collateral flow between the celiac trunk, superior
mesenteric artery, and inferior mesenteric artery.
Gradual occlusion of 2 of the 3 vessels is tolerable as
rich collateral branches form between these. Acute
occlusion of any of the vessels or their branches causes
acute intestinal ischemia and necrosis.
Discussion
The four processes:
1) Acute arterial embolus -usually from cardiogenic embolus
in pts w/ Afib or valvular disorders. SMA is the common
vessel affected as it has a less acute take off from aorta
2) Acute arterial thrombosis - chronic atherosclerotic plaque
at origin of vessel acutely thromboses
3) Chronic mesenteric ischemia - atherosclerosis of visceral
vessels results in abdominal pain (intestinal angina)
during times of increased blood demand (digestion)
4) Acute venous occlusion - venous thrombosis causes
cessation of venous outflow from intestines
*Non-occlusive mesenteric ischemia can also be seen in low-flow states
Discussion
Diagnosis - requires high degree of suspicion. Classically presents as
“pain out of proportion to physical exam” or severe pain w/o
peritoneal signs. The history of Cardiac disease, valvular disease, or
Afib should alert one to an embolic disease. Gold standard for
diagnosis is mesenteric angiogram, but CT angiogram is more and
more being used.
Treatment - requires aggressive resuscitation and hemodynamic
monitoring as patients become critically ill very quickly. Urgent
surgery w/ viseral revascularization (embolectomy, thrombectomy,
endarterectomy, or bypass) is required. After this, evaluation of
viability of bowel segments should be performed with resection of any
necrotic portions.
QUESTIONS ??????
References
• Townsend CM. Sabiston Textbook of Surgery.
17th Edition
• Cameron JL. Current Surgical Therapy. 8th
Edition
• Oldenburg et al. Acute Mesenteric Ischemia.
Arch Intern Med 164:1054-62. 2004
Acknowledgment
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