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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_1520_Библиотеки_им_академика_М_И_Перельмана
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440
K. Chapple
30.2 Epidemiology
It is diffi cult to ascertain the exact incidence. The condition is characteristically
seen in the elderly male hospitalized patient [ 4 ] . Up to 1% of patients undergoing
orthopedic surgery are affected [ 6 ] , as are 0.3% of burn patients [ 7 ] .
30.3 Pathophysiology
The majority of patients with ACPO have one or more predisposing factors
(Box 30.1 ), the commonest of which are nonoperative trauma, infections, orthope-
dic surgery, and cardiac disease [ 4, 8 ] . In addition, most patients have electrolyte
abnormalities and have taken opioid analgesics. ACPO is hypothesized to result
from the interaction of these metabolic, pharmacological, and traumatic factors in
some unknown fashion to cause an imbalance in the extrinsic colonic autonomic
Case Scenario 1
A 70-year-old gentleman on the medical ward with bronchopneumonia is
referred to the on-call surgical team with a 4-day history of abdominal pain,
distension, and constipation. He has a temperature of 37.6°C, pulse of 85 bpm,
and his blood pressure is 140/90. Examination reveals a markedly distended
abdomen with some mild, generalized tenderness. A chest X-ray and abdomi-
nal X-ray have been performed and demonstrate a dilated colon with no evi-
dence of intra-abdominal free air.
What is the likeliest diagnosis?
What would your initial management be?
What hematological and radiological investigations should be performed?
Case Scenario 2
A 70-year-old gentleman on the medical ward with bronchopneumonia is
referred to the on-call surgical team with a 4-day history of abdominal pain,
distension, and constipation. He has a temperature of 37.6°C, pulse of 85 bpm,
and his blood pressure is 140/90. Examination reveals a markedly distended
abdomen with some mild, generalized tenderness. A chest X-ray and abdomi-
nal X-ray have been performed and demonstrate a dilated colon with no evi-
dence of intra-abdominal free air. A CT scan of the abdomen and pelvis
demonstrates features consistent with acute colonic pseudo-obstruction, with
no evidence of colonic ischemia or perforation.
How would you further manage this patient?
441
30 Acute Colonic Pseudo-obstruction
innervation. Although direct evidence to support this theory is lacking, impairment
of the parasympathetic supply (which arises from the vagus nerve and sacral plexus
and causes increased colonic contractility) and/or hyperactivity of the sympathetic
nerves (which normally causes reduced motility) has been proposed to result in
colonic atony and hence a functional obstruction. Colonic wall stretch-sensitive
mechanoreceptors may then contribute to self-maintenance of the dilated state [ 9 ] .
30.4 Clinical Features
There is characteristic abdominal distension which may develop suddenly or gradu-
ally. Pain and vomiting may be present but are often absent. Failure to pass fl atus/
stools is only seen in 60% of patients [ 10 ] . Ischemia or perforation (which affects
up to 15% of patients and has an associated mortality rate of 50%) is suggested by
the presence of fever and abdominal tenderness, although these signs are also seen
without these complications [ 4 ] .
Box 30.1: Conditions Predisposing to the Development of ACPO
Medical
Advanced age
Sepsis (especially gram-negative)
Cardiac disorders (heart failure, myocardial infarction)
Respiratory disorders (pneumonia, respiratory failure, COPD)
Neurological disorders (Parkinson’s disease, multiple sclerosis, dementia)
Endocrine disorders (hypothyroidism, hypoparathyroidism)
Electrolyte imbalance (hypokalemia, hypocalcemia, hypomagnesemia,
hyponatremia, hypophosphatemia)
Drugs (antidepressants, phenothiazines, antiparkinsonians, opiates, baclofen)
Viral infections (Epstein–Barr virus and cytomegalovirus)
Renal failure
Autoimmune disorders (systemic lupus erythematosus, myasthenia gravis,
enteric leiomyositis)
Mitochondrial disorders
Amyloidosis
Trauma
Retroperitoneal trauma
Spinal cord injury
Postoperative
Abdominal/pelvic surgery
Knee/hip replacement
Spinal surgery
442
K. Chapple
30.5 Diagnosis
The diagnosis is typically suggested by the combination of clinical fi ndings and a
plain abdominal radiograph demonstrating a dilated colon. The dilatation is pre-
dominantly proximal, and a cut-off at the splenic fl exure or sigmoid colon is often
seen. The radiographic fi ndings are not specifi c, however, and up to 30% of patients
with apparent ACPO on abdominal X-ray (AXR) will ultimately have an alternative
diagnosis [
11, 12 ] . It is therefore mandatory that all patients with suspected ACPO
should undergo further imaging with either a water-soluble contrast enema (WSCE)
or computed tomography (CT). CT has a specifi city and sensitivity of 91% [ 13 ] and
WSCE a sensitivity of 96% and specifi city of 98% [ 12 ] . There has been no direct
comparison between the two techniques in the evaluation of ACPO. WSCE may
have therapeutic benefi ts should ACPO be diagnosed (see below), while CT scan-
ning is certainly easier to perform in the infi rm patient and has the additional advan-
tage of staging any coexisting malignant disease. No consensus exists on which
modality should be used, and the choice will invariably depend on local expertise
and availability.
30.6 Management
Only one set of practice guidelines exists for the management of ACPO [ 14 ] . Others
have suggested treatment algorithms [ 15, 16 ] . A simplifi ed algorithm is presented in
Fig. 30.1 . All advocate a period of conservative management in the absence of com-
plications requiring emergency surgery. Fasting, intravenous fl uid replacement, cor-
rection of electrolyte abnormalities, and treatment of any sepsis should be instituted.
Drugs delaying gut motility (opiates, anticholinergics, and calcium-channel blockers)
should be stopped and laxatives (especially osmotic laxatives such as lactulose)
avoided as they may promote bacterial fermentation and increase gas production.
Insertion of rectal and nasogastric tubes and posture changes to the knee-chest or
prone position are advocated despite the absence of evidence to support their use. Full
use of conservative measures, and in particular reduction of opiate usage, was associ-
ated with resolution of symptoms in 24 of 25 patients in one series [ 17 ] .
The duration of conservative management is debatable but generally should not
exceed 72 h [ 15 ] . Extending conservative management for 6 days leads to an
increased risk of complications [ 18 ] . Although the risk of cecal perforation rises
with increasing diameter, there is no defi ned measurement at which perforation
occurs. Perforation has been described in patients with a cecal diameter less than
10 cm whereas others have noted a cecal diameter of 16 cm without perforation [ 16 ] .
Mortality is, however, recognized to increase markedly when the cecal diameter
reaches 14 cm [ 4 ] .
Unsuccessful conservative therapy in a patient without complications warrants
further treatment using either pharmacological (neostigmine or WSCE) or colono-
scopic decompression. The American Society for Gastrointestinal Endoscopy
443
30 Acute Colonic Pseudo-obstruction
Definitive radiological
investigation (CT or WSCE)
Clinical and radiological (AXR)
suspicion of LBO
ACPO
Conservative management
48−72 hrs
Failure to resolve
Failure to resolve
Failure to resolve
Neostigmine
Colonoscopy
Surgery
Evidence of complication
(ischemia/perforation)
Resolution
Mechanical LBO
Continue supportive
management and consider
use of PEG
Fig. 30.1 Simplifi ed algorithm for the management of ACPO. LBO large bowel obstruction, PEG polyethylene glycol
444
K. Chapple
practice guidelines [ 14 ] and others [ 15, 16 ] have all advocated the use of neostig-
mine as fi rst-line treatment for patients failing conservative management.
Colonoscopic decompression should therefore be regarded as second-line treatment
for use only in patients who have failed, or have a contraindication to, pharmaco-
logical management. Despite evidence to the contrary, the use of a WSCE as a
therapeutic agent has not been advocated by previous authors.
30.7 Pharmacological Therapy
Evidence from three placebo-controlled double-blind randomized clinical trials
[ 19– 21 ] supports the use of intravenous neostigmine, an acetylcholinesterase inhib-
itor which prevents the breakdown of acetylcholine and hence increases parasympa-
thetic activity. All three trials show an initial response rate of 85–94% with a
long-term response of 64–89%. Although effective, serious side effects such as bra-
dycardia, hypotension, and bronchospasm may be seen (Box 30.2 ). Cardiorespiratory
monitoring is therefore mandatory, with atropine and/or glycopyrrolate available for
treatment of any such complications. The risk of side effects may be reduced by
starting with a 1 mg (instead of 2 mg) dose or using an infusion rather than bolus
therapy. Caution is needed in patients with asthma, recent myocardial infarction,
concurrent beta-blocker treatment, or renal failure. Because of the potentially seri-
ous side effects associated with neostigmine, its use is often avoided by medical
staff. A suggested protocol for its administration is provided in Box 30.3 .
There remains considerable anecdotal evidence surrounding the use of a WSCE as
a therapeutic measure in addition to its diagnostic role. Despite this enthusiasm, sci-
entifi c evidence is lacking, and only one study has been published investigating its
effi cacy. In this study [ 22 ] , 14 of 18 (78%) patients with ACPO were successfully
treated with a WSCE, including three patients who had failed prior colonoscopic
decompression. The water-soluble contrast (normally gastrografi n) is assumed to
exert its effect via its hyperosmolar nature, causing an increase in stool water and
content. The larger stool volume may then reduce colonic transit time by promoting
bulk fl ow. The exact place of a WSCE in the management pathway of the patient with
Box 30.2: Side Effects of Neostigmine
Cardiorespiratory
Hypotension
Bradycardia requiring atropine (occurs in approximately 10% patients)
Bronchospasm
Other
Abdominal cramping
Excessive salivation
Syncope
445
30 Acute Colonic Pseudo-obstruction
ACPO remains unclear. However, in suitable patients, it seems reasonable to consider
its use before embarking on potentially high-morbidity procedures such as colonos-
copy or surgery.
30.8 Endoscopic Therapy
Although the effi cacy has not been established in randomized clinical trials, several
retrospective studies report a success rate in up to 80% of patients [ 16 ] , although 20%
of these may recur and require further endoscopic intervention [ 8 ] . The procedure is
carried out on an unprepared bowel and requires an experienced endoscopist. Minimal
air insuffl ation and copious washouts and suction are required. It is not necessary to
examine the entire colon. The risk of perforation is high at around 2–3%. Placement of
a decompression tube is popular in the USA, although rarely performed in the UK, and
studies of its effi cacy are confl icting [ 23, 24 ] . Traditionally, the identifi cation of
mucosal ischemia has been seen as a contraindication to proceeding with decompres-
sion, but reports exist of such patients being successfully treated without surgery [ 25 ] .
30.9 Recurrence
A number of patients (around 20%) will experience recurrence after initial decom-
pression with neostigmine or colonoscopy. Recurrence may be minimized by con-
tinued maintenance of correct electrolyte levels and treatment of any ongoing sepsis
Box 30.3: Management Principles for the Use of Neostigmine
in a Patient with ACPO
Preadministration
Patient supine in bed on bed pan
Intravenous access
Continuous ECG monitoring
Supplemental oxygen
Atropine immediately available (0.5–1.0 mg iv bolus; can be repeated
every 3–5 min to a maximum dose of 3.0 mg)
Glycopyrrolate immediately available (0.1–0.5 mg iv bolus; can be repeated
every 2–3 min)
Administration
1–2 mg iv over 3–5 min or 0.4–0.8 mg/h iv over 24 h
Postadministration
Monitor blood oxygen saturation/pulse/blood pressure every 5 min for the
fi rst 30 min and then every 15 min for the next 2 h
Assess clinically for the fi rst 15–30 min
446
K. Chapple
but also by the use of polyethylene glycol (PEG), an osmotic laxative that lubricates
and softens the stool, increases fecal bulk, and reduces colonic transit time through
the left colon and rectum. In a small randomized clinical trial, the daily administra-
tion of a small dose of oral PEG solution (roughly equivalent to half a sachet of
“Klean-Prep”) for 7 days in patients with ACPO who had been successfully treated
with neostigmine resulted in no episodes of relapse in 15 patients compared to 5 of
15 patients treated with placebo [
26 ] . Signifi cant increases in stool and fl atus evacu-
ation and a reduction in colonic diameter were also seen with PEG use.
30.10 Surgery
Failure to respond to pharmacological and endoscopic therapy or actual/imminent
perforation is an indication for operative intervention. Surgery in this group of
patients has signifi cant morbidity and a mortality rate of 30–60%. Those patients
with a viable, nonperforated colon are generally better treated with a venting proce-
dure such as a cecostomy or colostomy. In the presence of complications, a segmen-
tal or subtotal colectomy, with or without anastomosis, should be performed. For
those patients considered unfi t for surgery, CT-guided percutaneous cecostomy has
been reported in a small number of patients [ 27 ] . Percutaneous endoscopic colostomy
tubes have also been placed in a few patients – success rates appear high although
there is a signifi cant rate of associated complications [ 16 ] . Percutaneous endoscopic
colostomy use is advocated by NICE for elderly or frail patients [ 28 ] .
30.11 Summary
ACPO is a common cause of acute large-bowel obstruction, typically found in hos-
pitalized patients with other signifi cant morbidity. A surgeon dealing with acute
abdominal cases should be familiar with the diagnosis and management of the con-
dition and follow the treatment algorithm in a logical sequence. Surgical interven-
tion carries a high mortality and should be reserved for patients where nonoperative
treatment has failed or where there are features of colonic ischemia.
Key Points
Acute colonic pseudo-obstruction is a not uncommon condition normally •
seen in the elderly patient with multiple comorbidities.
Clinical presentation and abdominal X-ray fi ndings are often indistinguish-•
able from mechanical large-bowel obstruction.
All patients with suspected ACPO require further imaging with either a CT •
scan or water-soluble contrast enema.
447
30 Acute Colonic Pseudo-obstruction
Case Scenario Answers 1
The clinical fi ndings are rather nonspecifi c, and although the likeliest diagno-
sis is that of an acute colonic pseudo-obstruction, a high index of suspicion
for other causes of an acute abdomen should be maintained. Other likely
potential causes include intra-abdominal sepsis or mechanical large-bowel
obstruction. Initial treatment, if not already instituted, should include keeping
the patient “nil by mouth,” obtaining intravenous access, commencing intra-
venous fl uid replacement, and inserting a urinary catheter and nasogastric
tube. Hematological investigations that should be ordered include a full blood
count, urea and electrolytes, liver function tests, and serum calcium, phos-
phate, and magnesium levels. There are no clinical indications for urgent sur-
gical intervention, and further radiological investigation is necessary. This
would normally be with a CT scan of the abdomen/pelvis although a WSCE
is an acceptable alternative.
Case Scenario Answers 2
Clinically and radiologically, there are no indications for emergency surgery.
Therefore, conservative measures should be initially utilized. Intravenous
fl uid replacement should be continued and any electrolyte abnormalities cor-
rected. His medication needs to be reviewed and opiates, calcium-channel
blockers, or laxatives stopped. A rectal catheter (“fl atus tube”) should be
inserted and nasogastric tube drainage continued. Treatment of the broncho-
pneumonia should be optimized in conjunction with the medical team. If there
has been no improvement in the next 48–72 h, then the use of neostigmine
should be considered. Failure of neostigmine therapy would be an indication
for colonoscopic decompression. Alternatively, decompression may be
attempted with a WSCE.
In the absence of complications requiring surgery, conservative manage-•
ment should be attempted for 48–72 h.
Failure of conservative management mandates treatment with neostigmine •
and, if unsuccessful, colonoscopic decompression.
Surgery carries a high morbidity and mortality rate and should only be •
performed if all other management strategies have failed.
448
K. Chapple
References
1. Zimmerman LM. Spastic ileus. Surg Gynecol Obstet. 1930;50:721.
2. Ogilvie H. Large-intestine colic due to sympathetic deprivation; a new clinical syndrome.
Br Med J. 1948;2:671–3.
3. Dudley HA, Sinclair IS, McLaren IF, McNair TJ, Newsam JE. Intestinal pseudo-obstruction.
J R Coll Surg Edinb. 1958;3:206–17.
4. Vanek VW, Al-Salti M. Acute pseudo-obstruction of the colon (Ogilvie’s syndrome). An anal-
ysis of 400 cases. Dis Colon Rectum. 1986;29:203–10.
5. Wegener M, Börsch G. Acute colonic pseudo-obstruction (Ogilvie’s syndrome). Presentation
of 14 of our own cases and analysis of 1027 cases reported in the literature. Surg Endosc.
1987;1:169–74.
6. Norwood MG, Lykostratis H, Garcea G, Berry DP. Acute colonic pseudo-obstruction follow-
ing major orthopaedic surgery. Colorectal Dis. 2005;7:496–9.
7. Kadeskey K, Purdue GF, Hunt JL. Acute pseudo-obstruction in critically ill patients with
burns. Burn Care Rehabil. 1995;16:132–5.
8. Jetmore AB, Timmcke AE, Gathright JB, Hicks TC, Ray JE, Baker JW. Ogilvie’s syndrome:
colonoscopic decompression and analysis of predisposing factors. Dis Colon Rectum.
1992;35:1135–42.
9. Hughes SF, Scott SM, Pilot MA, Williams NS. Adrenoceptors and colocolonic inhibitory
refl ex. Dig Dis Sci. 1999;44:2462–8.
10. Dorudi S, Berry AR, Kettlewell MG. Acute colonic pseudo-obstruction. Br J Surg.
1992;79:99–103.
11. Chapman AH, McNamara M, Porter G. The acute contrast enema in suspected large bowel
obstruction: value and technique. Clin Radiol. 1992;46:273–8.
12. Stewart J, Finan PJ, Courtney DF, Brennan TG. Does a water soluble contrast enema assist in
the management of acute large bowel obstruction: a prospective study of 117 cases. Br J Surg.
1984;71:799–801.
13. Beattie GC, Peters RT, Guy S, Mendelson RM. Computed tomography in the assessment of
suspected large bowel obstruction. ANZ J Surg. 2007;77:160–5.
14. Eisen GM, Baron TH, Dominitz JA, Faigel DO, Goldstein JL, Johanson JF, et al. Standards of
practice committee of the American Society for Gastrointestinal Endoscopy. Acute colonic
pseudo-obstruction. Gastrointest Endosc. 2002;56:789–92.
15. Saunders MD, Kimmey MB. Systematic review: acute colonic pseudo-obstruction. Aliment
Pharmacol Ther. 2005;22:917–25.
16. De Giorgio R, Knowles CH. Acute colonic pseudo-obstruction. Br J Surg. 2009;96:229–39.
17. Sloyer AF, Panella VS, Demas BE, Shike M, Lightdale CJ, Winawer SJ, Kurtz RC. Ogilvie’s
syndrome. Successful management without colonoscopy. Dig Dis Sci. 1988;33:1391–6.
18. Johnson CD, Rice CP, Kelvin FM, Foster WL, Williford ME. The radiologic evaluation of
gross cecal distension: emphasis on cecal ileus. Am J Roentgenol. 1985;145:1211–7.
19. Amaro R, Rogers AI. Neostigmine infusion: new standard of care for acute colonic pseudo-
obstruction? Am J Gastroenterol. 2000;95:304–5.
20. Ponec PJ, Saunders MD, Kimmey MB. Neostigmine for the treatment of acute colonic pseudo-
obstruction. N Engl J Med. 1999;341:137–41.
21. Van der Spoel JI, Oudemans-van Straaten HM, Stoutenbeek CP, Bosman RJ, Zandstra DF.
Neostigmine resolves critical illness-related colonic ileus in intensive care patients with mul-
tiple organ failure: a prospective, double-blind, placebo-controlled trial. Intensive Care Med.
2001;27:822–7.
22. Schermer CR, Hanosh JJ, Davis M, Pitcher DE. Ogilvie’s syndrome in the surgical patient: a
new therapeutic modality. J Gastrointest Surg. 1999;3:173–7.
23. Harig JM, Fumo DE, Loo FD, Parker HJ, Soergel KH, Helm JF, et al. Treatment of acute
nontoxic megacolon during colonoscopy: tube placement versus simple decompression.
Gastrointest Endosc. 1988;34:23–7.
449
30 Acute Colonic Pseudo-obstruction
24. Nano D, Prindiville T, Pauly M, Chow H, Ross K, Trudeau W. Colonoscopic therapy of acute
pseudoobstruction of the colon. Am J Gastroenterol. 1987;82:145–8.
25. Fiorto JJ, Schoen RE, Brandt LJ. Pseudo-obstruction associated with colonic ischaemia: suc-
cessful management with colonoscopic decompression. Am J Gastroenterol. 1991;86:
1472–6.
26. Sgouros SN, Vlachogiannakos J, Vassiliadis K, Bergele C, Stefanidis G, Nastos H, et al. Effect
of polyethylene glycol electrolyte balanced solution on patients with acute colonic pseudo
obstruction after resolution of colonic dilation: a prospective, randomised, placebo controlled
trial. Gut. 2006;55:638–42.
27. VanSonnerberg E, Varney RR, Casola G, Macaualy S, Wittich GR, Polansky AM, et al.
Percutaneous cecostomy for Ogilvie syndrome: laboratory observations and clinical experi-
ence. Radiology. 1990;175:679–82.
28. NICE guidance. Percutaneous endoscopic colostomy. UK:2005. Available from
www.nice.
org.uk/IPG161.
Accessed 02 Nov 2010.
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