Ogilvie syndrome pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmed Elsaiey, MBBCH [2]

The colonic pseudo-obstruction pathogenesis is believed to be due to impairment of the autonomic nervous system. The autonomic impairment may involve the parasympathetic fibers of S2-S4 which is responsible for innervation of the distal colon and may lead to atonic colon and proximal obstruction. In few cases, Ogilvie’s syndrome (colonic pseudo-obstruction) may show atrophic myopathy with thinned colonic wall and intact myenteric plexus.

• The association of spinal anaesthesias, drugs and nervous trauma has lead to the understanding that Ogilvie syndrome (colonic dilatation without true obstruction) may be caused by impairment of the autonomic nervous system.^[1][2][3]
• Damage to the parasympathetic fibers of S2 – S4 causes the distal colon to become atonic and become obstructed proximally.
• However, the exact mechanism is unknown, especially in patients who present with this syndrome without an obvious injury to the parasympathetic nerves.
• Acute colonic pseudo-obstruction occurs when the colon’s diameter rises quickly, which increases the tension in the colonic wall, leading to colonic ischemia and possibly, perforation with a diameter exceeding 10 – 12cm.
• A rare case of Ogilvie syndrome showed atrophic myopathy with a thinned out colonic wall, despite a perfectly intact myenteric plexus and unaffected ganglion cells, with no evidence of fibrosis or inflammation.

• The majority of paralytic (adynamic) ileus cases occur after major abdominal surgery, such as hysterectomy.
• Paralytic ileus is thought to occur with manipulation and trauma of the intestinal tract.
• Post operative dysmotility is associated with inflammation, impaired neural reflexes and the release of neural hormone peptides.
  • Inflammation:^[4]
    • Intestinal manipulation leads to intestinal ischemia, and shifting of endogenous cellular danger molecules and cytokines away from the site of trauma.
    • Leukocytic infiltration, macrophage and mast cell stimulation commences and causes muscular dysfunction, and therefore inflammation in the manipulated segment.
  • Neural reflexes:^[4]
    • Inhibitory sympathetic neural reflexes increase due to noxious spinal afferent signals, therefore, the use of epidural local anesthetics or topical capsaicin is encouraged to prevent paralytic ileus.^[5]
  • Neurohormonal peptides:^[6][7]
    • Inhibitory neurotransmitters are released and cause the gut motility to slow down.
    • Inhibitory neurotransmitters include, nitric oxide, vasoactive intestinal polypeptide, and substance P.

• Ogilvie’s syndrome (acute colonic psuedo-obstruction) may be associated with the following conditions:^[1]
  • Major surgeries as hip replacement surgery
  • Acute cardiac diseases as myocardial infarction
  • Systemic infections