Ogilvie syndrome
Encyclopedia
Ogilvie syndrome is the acute pseudoobstruction
and dilation of the colon in the absence of any mechanical obstruction in severely ill patients.
Colonic pseudo-obstruction is characterized by massive dilatation of the cecum (diameter > 10 cm) and right colon on abdominal X-ray. It is a type of megacolon, sometimes referred to as "acute megacolon," to distinguish it from toxic megacolon
.
The condition carries the name of the British surgeon Sir William Heneage Ogilvie (1887–1971), who first reported it in 1948.
and total joint replacement. It is also seen with neurologic disorders, serious infections, cardiorespiratory insufficiency, and metabolic disturbances. Drugs that disturb colonic motility (e.g., anticholinergic
s or opioid
analgesic
s) contribute to the development of this condition.
Acute megacolon develops because of abnormal intestinal motility. Normal colonic motility requires integration of myogenic, neural, and hormonal influences. The enteric nervous system is independent but is connected to the central nervous system by sympathetic and parasympathetic nerves. The targets of the enteric neurons are muscle cells, secretory cells, endocrine cells, microvasculature, and inflammatory cells. The neurons in the enteric plexuses are stimulated by a food bolus, which both distends the gut and stimulates the mucosal surface, leading to the release of factors that stimulate interneurons. The stimulated interneurons transmit excitatory signals proximally, which cause contraction and inhibitory signals distally, and these in turn cause relaxation. These signals are transmitted by the neurotransmitters acetylcholine and serotonin, among others.
Acute megacolon can also lead to ischemic necrosis in massively dilated intestinal segments. This is explained by Pascal's principle and Laplaces's law
. Pascal's principle states that the pressure within a cylindrical structure is the same, regardless of whether the structure is dilated, and Laplace's law states that the wall tension of a cylinder is equal to the pressure within the cylinder multiplied by the radius. Therefore, a dilated intestinal segment has a greater wall tension than a nondilated segment; if the dilatation and tension are sufficiently great, blood flow may be obstructed and ischemia of the bowel will occur. Ogilivies syndrome may precipitate Volvulus.
and a nasogastric tube
, but may require colonoscopic
decompression which is successful in 70% of the cases. A study published in the New England Journal of Medicine
showed that neostigmine
is a potent pharmacological way of decompressing the colon. According to the American Society for Gastrointestinal Endoscopy (ASGE), it should be considered prior to colonoscopic decompression. The use of neostigmine is not without risk since it can induce bradyarrhythmia and bronchospasms. Therefore atropine should be within immediate reach when this therapy is used.
Intestinal pseudoobstruction
Intestinal pseudoobstruction is decreased ability of the intestines to push food through, and often causes dilation of various parts of the bowel. It can be a primary condition or caused by another disease...
and dilation of the colon in the absence of any mechanical obstruction in severely ill patients.
Colonic pseudo-obstruction is characterized by massive dilatation of the cecum (diameter > 10 cm) and right colon on abdominal X-ray. It is a type of megacolon, sometimes referred to as "acute megacolon," to distinguish it from toxic megacolon
Toxic megacolon
Toxic megacolon is an acute form of colonic distension. It is characterized by a very dilated colon , accompanied by abdominal distension , and sometimes fever, abdominal pain, or shock....
.
The condition carries the name of the British surgeon Sir William Heneage Ogilvie (1887–1971), who first reported it in 1948.
Etiology
Ogilvie's syndrome may occur after surgery, especially following coronary artery bypass surgeryCoronary artery bypass surgery
Coronary artery bypass surgery, also coronary artery bypass graft surgery, and colloquially heart bypass or bypass surgery is a surgical procedure performed to relieve angina and reduce the risk of death from coronary artery disease...
and total joint replacement. It is also seen with neurologic disorders, serious infections, cardiorespiratory insufficiency, and metabolic disturbances. Drugs that disturb colonic motility (e.g., anticholinergic
Anticholinergic
An anticholinergic agent is a substance that blocks the neurotransmitter acetylcholine in the central and the peripheral nervous system. An example of an anticholinergic is dicycloverine, and the classic example is atropine....
s or opioid
Opioid
An opioid is a psychoactive chemical that works by binding to opioid receptors, which are found principally in the central and peripheral nervous system and the gastrointestinal tract...
analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
s) contribute to the development of this condition.
Pathophysiology
The exact mechanism behind the acute colonic pseudo-obstruction is not known. The probable explanation is imbalance in the regulation of colonic motor activity by the autonomic nervous system.Acute megacolon develops because of abnormal intestinal motility. Normal colonic motility requires integration of myogenic, neural, and hormonal influences. The enteric nervous system is independent but is connected to the central nervous system by sympathetic and parasympathetic nerves. The targets of the enteric neurons are muscle cells, secretory cells, endocrine cells, microvasculature, and inflammatory cells. The neurons in the enteric plexuses are stimulated by a food bolus, which both distends the gut and stimulates the mucosal surface, leading to the release of factors that stimulate interneurons. The stimulated interneurons transmit excitatory signals proximally, which cause contraction and inhibitory signals distally, and these in turn cause relaxation. These signals are transmitted by the neurotransmitters acetylcholine and serotonin, among others.
Acute megacolon can also lead to ischemic necrosis in massively dilated intestinal segments. This is explained by Pascal's principle and Laplaces's law
Young–Laplace equation
In physics, the Young–Laplace equation is a nonlinear partial differential equation that describes the capillary pressure difference sustained across the interface between two static fluids, such as water and air, due to the phenomenon of surface tension or wall tension, although usage on the...
. Pascal's principle states that the pressure within a cylindrical structure is the same, regardless of whether the structure is dilated, and Laplace's law states that the wall tension of a cylinder is equal to the pressure within the cylinder multiplied by the radius. Therefore, a dilated intestinal segment has a greater wall tension than a nondilated segment; if the dilatation and tension are sufficiently great, blood flow may be obstructed and ischemia of the bowel will occur. Ogilivies syndrome may precipitate Volvulus.
Signs and symptoms
Usually the patient has abdominal distention, pain and altered bowel movements. There may also be nausea and vomiting.Treatment
It usually resolves with conservative therapy stopping oral ingestions, i.e. nil per osNil per os
Nil per os is a medical instruction meaning to withhold oral food and fluids from a patient for various reasons. It is a Latin phrase which translates as "nothing through the mouth". In the United Kingdom it is translated as nil by mouth .Typical reasons for NPO instructions are the prevention...
and a nasogastric tube
Feeding tube
A feeding tube is a medical device used to provide nutrition to patients who cannot obtain nutrition by swallowing. The state of being fed by a feeding tube is called gavage, enteral feeding or tube feeding...
, but may require colonoscopic
Colonoscopy
Colonoscopy is the endoscopic examination of the large bowel and the distal part of the small bowel with a CCD camera or a fiber optic camera on a flexible tube passed through the anus. It may provide a visual diagnosis and grants the opportunity for biopsy or removal of suspected...
decompression which is successful in 70% of the cases. A study published in the New England Journal of Medicine
New England Journal of Medicine
The New England Journal of Medicine is an English-language peer-reviewed medical journal published by the Massachusetts Medical Society. It describes itself as the oldest continuously published medical journal in the world.-History:...
showed that neostigmine
Neostigmine
Neostigmine is a parasympathomimetic that acts as a reversible acetylcholinesterase inhibitor.- Synthesis :Neostigmine was first synthesized by Aeschlimann and Reinert in 1931....
is a potent pharmacological way of decompressing the colon. According to the American Society for Gastrointestinal Endoscopy (ASGE), it should be considered prior to colonoscopic decompression. The use of neostigmine is not without risk since it can induce bradyarrhythmia and bronchospasms. Therefore atropine should be within immediate reach when this therapy is used.