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1044 PART 9: Gastrointestinal Disorders

detecting pulsatile Doppler signals at the mesenteric arcades and intestinal TABLE 109-3 Recent Acute Mesenteric Revascularization Outcomes
surface. The goal of intestinal resection is to remove areas of nonviable
bowel and leave sufficient viable bowel to sustain independent life. Author Patients No. Perioperative Mortality (%) 5-Year (Survival %)
Segments of the terminal ileum are critical to preserve if viable due to Bjorck et al, 2002 1 58 43 67
the specialized absorptive functions it performs. In general, if a large seg- 5
ment (>6 ft of small intestine) of obviously viable bowel can be identi- Park et al, 2002 58 32 32
fied, then nonviable segments should be resected liberally. Restoration of Rawat et al, 2010 74 76 17
continuity is preferred; anastomoses may be hand sewn to preserve more Gupta et al, 2011 71 156 28
functioning intestine, but a stapler may be quicker. In the presence of 73
gross contamination or doubtful viability, creating a stoma may be con- Newton et al, 2011 142 30
sidered, but in this setting a “second look” laparotomy (after 18-36 hours) Ryer et al, 2012 72 93 45
would allow adequate resuscitation of the patient and clearer differentiation
of bowel viability. At the time of the second look, previously marginal of short-bowel syndrome may necessitate home parenteral feeding
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segments will have become necrotic or viable. Further resection may be for a period in many and for the long term in a third of survivors.
54
needed, or bowel continuity can be restored and the stoma matured. Surveillance of mesenteric bypass grafts is suggested to improve the
■ POSTOPERATIVE CARE AND FOLLOW-UP SURVEILLANCE secondary patency and avoid recurrent ischemia. 56
Postoperative care must be in an intensive care setting if acceptable
results are to be achieved in these high-risk patients. Second-look KEY REFERENCES
laparotomy should be the rule rather than the exception and, when • Acosta S, Nilsson T. Current status on plasma biomarkers
planned at the initial surgery, must be adhered to despite the patient’s for acute mesenteric ischemia. J Thromb Thrombolysis. May
clinical course. Reperfusion of the ischemic intestine leads to inflam- 2012;33(4):355-361.
19
matory edema of the affected segments, and this, combined with large
volumes of intraluminal fluid sequestration, places these patients at risk • Akyildiz H, Akcan A, Oztürk A, Sozuer E, Kucuk C, Karahan I. The
for developing abdominal compartment syndrome in the postoperative correlation of the D-dimer test and biphasic computed tomography
period (see Chap. 114). Beyond basic fluid management and cardiore- with mesenteric computed tomography angiography in the diagnosis
53
spiratory support, attention must be given to nutritional support. In the of acute mesenteric ischemia. Am J Surg. April 2009;197(4):429-433.
catabolic postoperative recovery phase, demands are increased, often • Gupta PK, Natarajan B, Gupta H, Fang X, Fitzgibbons RJ Jr.
on a background of chronic malnourishment and often compounded Morbidity and mortality after bowel resection for acute mesenteric
by dysfunctional reperfused bowel and short-bowel syndromes. After ischemia. Surgery. October 2011;150(4):779-787.
major resections, postoperative parenteral nutrition (TPN) invariably • Liem TK, Segall JA, Wei W, Landry GH, Taylor LM, Moneta GL.
is required, often for extended periods, because even viable segments J Vasc Surg. 2007;45(5):922-928.
often have prolonged absorptive and motility dysfunction for extended • Milner R, Woo EY, Carpenter JP. Superior mesenteric artery angio-
periods. TPN should be started as soon as possible. Postoperative hep- plasty and stenting via a retrograde approach in a patient with
54
arin therapy in those with embolic occlusion should be continued in the bowel ischemia—a case report. Vasc Endovasc Surg. 2004;38:89-91.
absence of bleeding diathesis, and oral warfarin should be commenced,
with a target International Normalized Ratio (INR) of 2.0 to 3.0, as soon • Newton WB III, Sagransky MJ, Andrews JS, et al. Outcomes of
revascularized acute mesenteric ischemia in the American College
as oral diet is resumed. In the case of embolic disease, a primary source
should be sought by transthoracic or transesophageal echocardiography of Surgeons National Surgical Quality Improvement Program.
Am Surg. July 2011;77(7):832-838.
and full aortic (chest and abdomen) CT scanning if a cardiac source
is not identified. Thoracic aortic mural thrombus is an infrequent • Oliva IB, Davarpanah AH, Rybicki FJ, et al. ACR appropriate-
58
cause of emboli that is being recognized with increasing frequency by ness criteria(®) imaging of mesenteric ischemia. Abdom Imaging.
transesophageal echocardiography and confirmed by CT scanning. January 9, 2013. [Epub ahead of print] PMID:23296712.
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Thrombotic occlusions especially of the mesenteric vein should prompt • Rawat N, Gibbons CP; Joint Vascular Research Group. Surgical
a thrombophilia evaluation. Secondary prevention strategies such as or endovascular treatment for chronic mesenteric ischemia: a
smoking cessation and dietary and therapeutic lipid control may prevent multicenter study. Ann Vasc Surg. October 2010;24(7):935-945.
further cerebrovascular and mesenteric vascular events. • Ryer EJ, Kalra M, Oderich GS, et al. Revascularization for acute
mesenteric ischemia. J Vasc Surg. June 2012;55(6):1682-1689.
PROGNOSIS • Wyers MC, Powell RJ, Nolan BW, Cronenwett JL. Retrograde mes-
enteric stenting during laparotomy for acute occlusive mesenteric
Despite numerous advances in the assessment, diagnosis, and treatment ischemia. J Vasc Surg. 2007;45:269-275.
of mesenteric ischemia, the mortality rate remains very high even in
specialist centers (Table 109-3). Diagnostic delay is perhaps the greatest
hurdle to improvement. Most patients who survive the initial periop- REFERENCES
erative period regain independent living, with results comparable with
elective revascularization of chronic mesenteric ischemia. The sequelae Complete references available online at www.mhprofessional.com/hall
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