Features and Outcomes of Patients With Ischemia Isolated to the Right Side of the Colon When Accompanied or Followed by Acute Mesenteric Ischemia

Background & Aims: Patients with ischemia isolated to the right side of the colon (IRCI) frequently have poor outcomes. IRCI and acute mesenteric ischemia (AMI) are caused by reductions in blood supply from the superior mesenteric artery and its branches. We investigated a group of patients with IRCI associated with AMI that developed initially or shortly thereafter, and compared outcomes of patients with IRCI and AMI vs those with only IRCI. Methods: We performed a retrospective study of data collected from 313 consecutive patients with colonic ischemia who were hospitalized at Montefiore Medical Center in New York from 1998 through 2009. Based on colonoscopy, biopsy analyses, and surgery reports, we identified patients with IRCI with concurrent or proximately developing AMI (IRCI+AMI) and those with only IRCI. Demographics, evaluation, disease distribution, and outcome data were compared between groups. Results: Of 313 patients with colonic ischemia, 20.8% had IRCI; of these, 84.6% had only IRCI and 15.4% had IRCI+AMI. Chronic obstructive pulmonary disease was found more frequently in patients with IRCI+AMI (40.0%) than in patients with IRCI alone (12.7%; P < .05). At the time of IRCI diagnosis, mean levels of blood urea nitrogen were significantly higher in patients with IRCI+AMI than with IRCI alone (37.9 ± 14.4 mEq/L vs 26.4 ± 18.8 mEq/L; P < .05), as were mean white blood cell counts (20.3 ± 12.1 vs 12.7 ± 6.8 × 10³/μL; P < .01). A higher proportion of patients with IRCI+AMI underwent surgery than patients with only IRCI (100.0% vs 43.1%; P = .001), and 30-day mortality was higher among patients with IRCI+AMI (70.0% vs 14.5% for patients with only IRCI; P < .001). Conclusions: Based on an analysis of 313 patients with colonic ischemia, patients with IRCI+AMI have even more severe disease than those with IRCI alone. Chronic obstructive pulmonary disease was observed more frequently in patients with IRCI+AMI. Patients with IRCI+AMI had increased levels of blood urea nitrogen and/or white blood cell counts. Patients with IRCI should undergo vascular imaging analyses immediately to detect AMI; patients without AMI should be monitored closely for its subsequent development.