Mesenteric ischemia natural history, complications and prognosis

If left untreated, 99% of patients with mesenteric ischemia may progress to develop intestinal gangrene, septic shock and subsequent multiorgan failure. The progressive phases of mesenteric ischemia include a hyperactive phase, paralytic phase and a shock phase. The prognosis largely depends on prompt diagnosis and timely medical/surgical intervention depending on the underlying etiology. Poor prognostic factors include signs such as: tachypnea, tachycardia, hypotension and altered mental status. Common complications of mesenteric ischemia include: bowel infarction, perforation, sepsis, peritonitis, septic shock, and multiorgan failure.

• If left untreated, 99% of patients with mesenteric ischemia progress to develop intestinal gangrene, septic shock and subsequent multiorgan failure.
• It can be divided into three phases:^[1][2]
  • Hyperactive phase
  • Paralytic phase
  • Shock

• Hyperactive phase is the phase of mesenteric ischemia in which the most common symptoms are excruciating abdominal pain and the passage of bloody stools.
• Many patients get better and do not progress beyond this phase if treated in time.

• Paralytic phase follows if ischemia continues.
• In this phase, the abdominal pain becomes more widespread, the abdomen becomes tender to touch, and bowel motility decreases, resulting in abdominal bloating, no further bloody stools, and absent bowel sounds on exam.

• Shock phase can develop as fluids start to leak through the damaged colon lining.
• This can result in shock and metabolic acidosis with dehydration, low blood pressure, rapid heart rate, and confusion.
• Patients who progress to this phase are often critically ill and require intensive care.

• Mesenteric ischemia is difficult to diagnose.^[3]
• The prognosis mostly depends on prompt diagnosis and timely medical/surgical intervention depending on the underlying etiology.^[4]
• Generally, the prognosis is poor when there is delay in the treatment, ranging from 0% to 40%.^[5]
• In case of occlusive type of acute mesenteric ischemia, mortality can be up to 90% without surgical intervention.^[6][7]

• In embolic type of mesenteric arterial occlusion, there is improved outcome after surgical intervention, which is not the case in thrombotic and non-occlusive type of mesenteric ischemia.

• Venous thrombosis – 32% mortality
• Arterial embolism – 54% mortality
• Arterial thrombosis – 77% mortality
• Non-occlusive ischemia – 70-90% mortality^[8]

Prognostic indicators of mesenteric ischemia:^[9]

• Mannheim Peritonitis Index (MPI)
• Platelet to lymphocyte ratio

• Common complications of mesenteric ischemia include:
  • Bowel infarction
  • Perforation
  • Sepsis
  • Peritonitis
  • Septic shock
  • Multiorgan failure