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Volvulus
is the rotation of a loop of bowel on its mesenteric axis,
resulting in partial or complete obstruction. The most
common portion affected is the sigmoid colon (Figure
7.33).
Figure 7.34 shows the X-ray appearance.
Diagnosis
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Sudden
onset of severe, colicky abdominal pain |
| :: |
Absolute
constipation |
| :: |
Rapidly
progressive but moderate abdominal distension |
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Associated
with tachycardia, hypotension and fever |
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Empty
rectum |
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Nausea
and vomiting are late symptoms |
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Frequently
progresses to strangulation and gangrene. |
Medical management
Resuscitate dehydrated patients with intravenous fluids
and correct anaemia if required. Insert a nasogastric tube
if the patient is vomiting. Antibiotics that provide aerobic,
gram negative and anaerobic coverage should be administered
if the volvulus is suspected to be gangrenous.
Non-operative reduction of subacute volvulus
Subacute volvulus does not require emergency reduction,
but should be treated urgently (within 3 hours).
Technique
| 1 |
Sedation
may be helpful, but do not give an anaesthetic: the
patient’s reaction to pain, if the sigmoidoscope
is incorrectly placed, is a protection against traumatic
perforation of the bowel wall. Put on a waterproof
apron and place the patient face down in a knee-elbow
position (which may itself cause derotation of the
bowel) or use the left lateral position. |
| 2 |
Without
using force, pass the well-lubricated sigmoidoscope
as high as it can go into the colon with the bowel
lumen completely visualized. Lubricate the rectal tube
and introduce it through the sigmoidoscope until it
meets the obstruction marking the lower part of the
twisted loop. Gently rotate the rectal tube, allowing
its tip to skip into the distal limb. Keep your face
well aside from the tube and the sigmoidoscope at this
stage, as successful entry into the volvulus will be
evidenced by a sudden profuse outpouring of foul-smelling
liquid faeces mixed with gas. If you are not experienced
in passing a sigmoidoscope you could still simply pass
a well lubricated rectal tube and manoeuvre it as described. |
| 3 |
After
decompression, withdraw the sigmoidoscope, but leave
the rectal tube in position strapped to the perineum
and buttock. It should be retained in this position
for 3–4 days, if possible. Should the rectal
tube be expelled, gently reintroduce it without using
the sigmoidoscope. Indeed, sigmoidoscopy is not essential
even for the initial introduction of the tube, though
it facilitates the procedure. |
| 4 |
If
this manoeuvre fails to untwist the volvulus, perform
laparotomy immediately. |
Operative management
| 1 |
Anaesthetize
the patient and perform a laparotomy with a lower midline
incision. |
| 2 |
At
laparotomy, untwist the volvulus.
If the bowel is viable, have an assistant pass a rectal tube while you guide
it along the sigmoid colon. Suture the tube to the buttocks and close the abdomen.
Remove the tube after 4 days.
If the bowel is not viable, resect the dead section, perform an end colostomy
and close the rectum in two layers. |
After
recovery, refer the patient for elective sigmoid colectomy
or, in the case of a resection, for closure of the colostomy.
Colostomy closure is safely performed 3 months after resection.
See pages 6–15 and 6–16
for the description of end colostomy and refer to Figures
6.50 to 6.54.
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Volvulus of the sigmoid colon is:
– Usually sub-acute
– Associated with repeated previous episodes
– The most common cause of large bowel obstruction
seen at the district hospital
– Associated with massive but soft abdominal distension
– Seen in well hydrated patients
– Complicated with vomiting and abdominal pain as
a late finding
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When neglected, can progress to strangulation
and gangrene
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Sub-acute sigmoid volvulus can be reduced by the placement
of a rectal tube
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Refer patients after non-operative or operative volvulus
reduction for elective surgical management
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Suspect gangrene if you see darkened bowel or blood stained
fluid at sigmoidoscopy
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Operate if you suspect gangrene and, if necessary, perform
a sigmoid resection with colostomy
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The generalist at the district hospital should be capable
of performing a colostomy but should refer patients to
a qualified surgeon for colonic anastomosis and colostomy
closures.
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