Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Suspect in severe pain with risk factors (AF, atherosclerosis, low-flow states).
- CTA immediately; initiate heparin; start broad antibiotics and resuscitation.
- Endovascular embolectomy/thrombectomy or open revascularization; resect nonviable bowel; plan second-look in 24–48 h.
- Post-op ICU care; optimize nutrition; secondary prevention (anticoagulation/vascular risk).
Clinical Synopsis & Reasoning
Severe abdominal pain out of proportion to exam suggests mesenteric ischemia. Obtain CTA immediately, give aggressive fluids and systemic heparin, start broad antibiotics, and arrange urgent endovascular or open revascularization with bowel assessment; plan for second-look laparotomy.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|
| CTA abdomen/pelvis with arterial phase | Diagnosis/anatomy | Embolic SMA occlusion, thrombosis, NOMI | Gold standard |
| Lactate, ABG/base deficit, phosphate | Severity | Tissue hypoperfusion | Trend kinetics |
| Bedside ultrasound (limited) | Adjunct | Poor sensitivity | Do not delay CTA |
High-Risk & Disposition Triggers
| Trigger | Why it matters | Action |
|---|
| Peritonitis or lactic acidosis | Transmural necrosis risk | Immediate OR; broad antibiotics |
| AF or low-flow states | Embolic/non-occlusive etiologies | Heparinization; correct hemodynamics |
| Delayed diagnosis >12 h | Worse survival | Escalate to surgery/endovascular rapidly |
| Elevated phosphate and worsening base deficit | Advanced ischemia | ICU; prepare for re-look laparotomy |
| Renal insufficiency limiting contrast | Diagnostic delay risk | Use CTA judiciously; discuss risks; consider alternative imaging if needed |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|
| Unfractionated heparin bolus 80 U/kg → infusion | Anticoagulant | Immediate | Prevents propagation | Monitor aPTT/anti-Xa |
| Piperacillin-tazobactam or Carbapenem + Metronidazole | Broad antibiotics | Hours | Translocation/necrosis coverage | Tailor to cultures |
| Vasopressor choice (norepinephrine) with flow optimization | Hemodynamics | Minutes | Avoid splanchnic hypoperfusion | MAP targets individualized |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- WSES Guidelines for Acute Mesenteric Ischemia — Link