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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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451
S.R. Brown et al. (eds.), Contemporary Coloproctology,
DOI 10.1007/978-0-85729-889-8_31, © Springer-Verlag London Limited 2012
31.1 Introduction
A description of colonic volvulus occurs in the Ebers Papyrus, the world’s oldest
medical document circa 1500 BC [ 1 ] . Notwithstanding thousands of years of expe-
rience, its management can at fi rst appear somewhat controversial (Table 31.1 ). Its
relative rarity (1.7 per 100,000 per year in UK) [ 2 ] and the fact that it often affects
elderly, psychiatric, and institutionalized patients [ 3 ] may have made it an unfavor-
able subject for study. However, despite these limitations, there is now suffi cient
published data to make evidence-based management decisions in most cases.
Volvulus most commonly affects the sigmoid colon and accounts for somewhere
in the region of 10% of presentations with acute large bowel should be obstruction
worldwide. Caecal volvulus is a more unusual condition, accounting for only 15–20%
of cases of colonic volvulus. Volvulus of other parts of the colon (transverse and
splenic fl exure) is very unusual, and a surgeon may not encounter a case throughout
their working life.
31.2 Why Does the Sigmoid Volve (Fig. 31.1 ) ?
Elongation of the colon and mesentery in conjunction with a narrow posterior mes-
enteric attachment allows rotation. Chronic constipation and a diet high in insoluble
fi bre can both cause the necessary colonic elongation.
L. M. Hunt , M.D., FRCS, M.B.Ch.B.
Department of Colorectal Surgery , Northern General Hospital,
Sheffi eld Teaching Hospitals NHS Foundation Trust ,
Herries Road , Sheffi eld , S5 7AU , UK
e-mail: lesley.hunt@sth.nhs.uk
Chapter 31
Colonic Volvulus
Lesley M. Hunt
452
L.M. Hunt
31.3 And Who Does It Happen To?
In the West, sigmoid volvulus happens mainly to the elderly, infi rm, and those
with chronic psychiatric illness, particularly when institutionalized [ 3, 4 ] . This is
probably in part drug related (antimuscarinics, antipsychotics, tranquilizers, and
chronic use of stimulant laxatives are particularly implicated). However, with
increasing globalization, we must be aware that it can also present in young, fi t
patients, particularly men from Africa, South America, and the Middle East
(related to insoluble fi bre intake). Very rarely, it can present in pregnancy, as the
gravid uterus displaces normal anatomy [ 5 ] . It can be precipitated by trauma,
underlying bowel pathology, nutritional problems, and chronic worm infestation
and is described in children [ 6 ] .
31.4 Management of the Acute Episode (Box 31.1 )
Table 31.1 Why is there controversy?
Literature is
mediocre
Failure to compare like
with like
Variation in patient
population Diagnostic uncertainty
Small series (most
<20 patient)
many
historical
Mortality per patient vs.
per episode
Elderly frail
Volvulus can occur with
proximal megacolon
Retrospective
series
Acute vs. chronic
presentation
Psychiatric patients Historical papers rely on
AXR (diagnostic in
50%)
One randomized
trial
Viable vs. gangrenous
bowel
Fit young men in
developing
countries
Variation in incidence
may refl ect variation
in diagnostic rigor
Few prospective
audits
Elective vs. emergency
surgery
Pregnant women Decompression works
for both volvulus and
pseudoobstruction
No controlled
studies
Comorbidities
poorly recorded
Box 31.1: Management of Sigmoid Volvulus – the questions to ask
yourself
Is it volvulus?
Is it safe to attempt non operative de-rotation – If yes, do it urgently.
Is emergency surgery needed? What operation should be done?
Is planned surgery needed? What planned operation should be done?
Is percutaneous endoscopic colostomy appropriate?
453
31 Colon ic Volvulus
Presentation can be acute, subacute, or occasionally chronic. Although the popula-
tion we see does not always inspire surgical enthusiasm, remember acute volvulus
can rapidly lead to closed loop obstruction. One hundred and eighty degree of twist
produces luminal obstruction and 360° venous obstruction, which, if not rapidly
resolved, will progress to gangrene and death. Western mortality estimates vary
between 7% and 40% per episode. If the patient presents with infarction, mortality
is 26–80% [
3, 7 ] . As far back as 1905, Moynihan wrote that mortality over 10% was
the “mortality of delay” [ 1 ] .
Fig. 31.1 Line drawing of a sigmoid volvulus
454
L.M. Hunt
31.5 Urgent Clinical Assessment Is Required to Establish
Firstly, is there peritonitis? Secondly, is this a volvulus, and if it is, is it safe to
attempt nonoperative decompression? Or does this patient require urgent surgery?
Finally, what is this patient’s level of fi tness?
31.6 Is It Volvulus?
A good history may not be forthcoming. Severe pain is unusual, despite the massive
distension, and if present is a warning of ischaemia (Box 31.2 ) .
31.7 Investigations
31.7.1 Blood Tests
Electrolyte disturbance is common and usually correctable (except of course a high
potassium indicating dead bowel, which should be treated but can only be corrected
by urgent resection). White cell count and lactate can be useful indicators of com-
promised bowel.
31.8 Can You Diagnose a Sigmoid Volvulus on a Plain AXR
(Box
31.3 ) ?
Yes, but not always, so beware. A plain fi lm is useful test as it:
(a) Establishes that there is a problem
(b) Shows other causes of distension such as small-bowel obstruction
Beyond this, its value is less than we would wish, being diagnostic of sigmoid
volvulus in only 37–83% [ 6– 10 ] . Even retrospectively, the radiographic signs of
confi rmed volvulus are only present in 75% [ 11 ] . Sensitive signs such as absence of
Box 31.2: The Rectal Examination
Distended and empty in pseudoobstruction
Distended and full in faecal impaction
Collapsed and empty in volvulus, malignant obstruction, proximal
obstruction
Flatus on withdrawal suggests pseudoobstruction
455
31 Colon ic Volvulus
rectal gas are of course nonspecifi c. When CT scanograms were assessed against
the contemporaneous cross-sectional images, the classic radiographic features of
volvulus were seen on only 52% [ 12 ] .
31.9 Imaging in Sigmoid Volvulus (Box 31.3 )
Emergency CT scanning is often diagnostic where AXR is not, but classic signs may
be absent even on CT. Frank necrosis should be seen; however, signs indicating colonic
ischemia can correlate poorly with clinical evidence [ 12 ] . Rectal contrast during CT
may reduce oedema and facilitate de-rotation, but this has not been scientifi cally
assessed. Sometimes, a water-soluble contrast study is used to establish the diagnosis,
often by chance where the original working diagnosis was pseudoobstruction, and a
contrast study was arranged to exclude a mechanical obstruction. The typical appear-
ances are of a tapering stricture, said to look like a “bird’s beak.”
Box 31.3: Radiological Features of a Sigmoid Volvulus
(CT Versus Plain AXR)
Plain radiographic signs of sigmoid
volvulus CT signs of sigmoid volvulus
Disproportionate distension
of sigmoid (76%)
Single transition
point 95%
Absence of gas in rectum (90%) Whirling of the mesenteric vessels
Thick bowel walls seen
(if chronic)
Bird’s beak sign (short tapering
obstruction)
Fluid level in each
loop
X marks the spot (crossing
sigmoid limbs) 43%
Summation line (overlapping
of medial walls of the loop)
Split-wall sign (seen when twist
not so tight) 52%
Approximation of the medial walls
of the loop points to RUQ
Inverted U-shaped sigmoid (86%)
Ace of spades sign
Bent inner tube sign
Coffee bean sign (midline
crease corresponding to
mesenteric root) (76%)
Convergence of the two sigmoid
limbs low down in the LIF
Lack of haustral folds in sigmoid loop % taken from Levsky et al. [ 12 ]
456
L.M. Hunt
31.10 Nonoperative Decompression
Hippocrates described decompression using a suppository “10 digits long” [ 1 ] . In
1947, Bruusgaard introduced modern nonoperative de-rotation [ 13 ] . This remains
the initial management of choice in cases without ischaemia. Although successful
using either rigid sigmoidoscope [ 9, 13 ] or colonoscope in 78–91% of cases [ 14–
18 ] , it is not without risk, with a reported mortality of 1–14%, although some deaths
are attributable to comorbidity [ 9, 16, 17 ] . Spontaneous reduction is described in
2% of cases, but please don’t wait for this to happen! [ 19 ]
31.11 Do It with a Rigid Sigmoidoscope
This should be attempted urgently by an experienced person. It is technically diffi cult.
The rectum will be collapsed, and the twist encountered at the rectosigmoid junction
(RSJ). The RSJ should be negotiated under direct vision to assess colonic viability.
Bloody bowel contents or discolored mucosa suggest necrosis in which case de-rota-
tion will be very diffi cult and dangerous. De-rotation of compromised bowel is likely
to cause circulatory collapse and death. Successful de-rotation leads to an explosion
of gas and some feces. A lubricated soft fl atus tube is then gently inserted into the
sigmoid colon under direct vision. The fl atus tube is taped externally and left in situ
for 2–5 days. Some recommend an AXR, but this is not usually necessary.
31.12 Or a Flexible Endoscope
Although not always as immediately available, fl exible endoscopy allows easier
maintenance of the view and better mucosal assessment. Therefore, it may be safer.
Perforation by insuffl ation has been described [ 14 ] .
Following de-rotation by either method, a mucosal mark is almost always visible. If
absent or if the procedure was easy or gradual, the diagnosis is probably not volvulus.
31.13 Or Other Means?
Barium enema decompression has many disadvantages not least that it is only suc-
cessful in 20% [ 20 ] . Prior percutaneous decompression, successful in only 71%,
also poses a signifi cant risk of peritoneal contamination [ 21 ] . Neither procedure can
be advocated. A minority of authors advocate immediate surgery. The evidence
does not support this where the bowel is viable [ 1, 9, 16 ] .
457
31 Colon ic Volvulus
31.14 What Happens Next?
The “hope it doesn’t happen again” expectant management policy sometimes seen
in the UK is largely unreported and not supported by the literature. Recurrence
occurs in 8–90%, and 50% occurs within 2 years [ 1, 2, 6, 9, 16, 22 ] (Fig. 31.2 ).
Sixty percent of presenting patients have had a recent (2–33 months) prior episode
[ 1 ] , and 10–60% of recurrences are fatal [ 2, 15 ] . An overall mortality of 22% from
sigmoid volvulus equates to a 10% mortality per admission [ 1 ] . For most patients,
operative mortality is less than the mortality associated with recurrence [ 1, 2, 15 ] .
Age is no reason to eschew surgery. Survival is maximized in the fi t, elderly by early
elective resection. The mortality associated with recurrence and its treatment in the
elderly has been found to be 21% compared with a 5.6% mortality from elective
surgery [ 18 ] .
31.15 Emergency Surgery
In the West, less than 10% of patients present with gangrene [ 16 ] . Mortality is
0–75% for these cases [ 6, 9, 10, 15, 16, 18, 22 ] . It goes without saying that urgent
resection is the only option. Hartmann or Paul–Mikulicz-type procedures are the
operations of choice. Primary anastomosis in the presence of gangrenous bowel has
a 60% reported mortality whereas the average of other series is 38% [ 16 ] . In the
only randomized study in the literature, 14 West African patients with gangrenous
26 patients:
successful
nonoperative
de rotation
1 death from
sepsis post de
rotation
10 operated
during
initial admission
7 returned for
elective surgery
3 “lost to follow
up”
5 recurrences
(between 3 days
and 14 months)
4 gangrenous
colon
with recurrence
3 deaths within
30 days
Fig. 31.2 Outcome following successful nonoperative de-rotation (Safi oleas et al. [ 15 ] )
458
L.M. Hunt
colon were randomized to Hartmann’s procedure or primary anastomosis. Mortality
was 12.5% for Hartmann’s and 33% for primary anastomosis [ 23 ] .
Intraoperatively, it is desirable to, at least, clamp and, if possible, divide the mes-
enteric vessels prior to untwisting the colon. Untwisting without this precaution is
likely to cause endotoxic shock and cardiac arrest.
31.16 Elective/Scheduled Surgery
31.16.1 Timing
If the patient is fi t and agrees, operation should be carried out. The best results are
achieved by nonoperative decompression followed by scheduled surgery [ 1, 16– 18 ] .
Operation is urgent as fatal recurrence can happen in weeks. “Same admission”
surgery avoids this additional mortality risk [ 15, 24 ] . Although, previously, some
have suggested waiting 10 days to 4 weeks, the data now supports getting on with it
[ 13, 16, 17, 19 ] . There is no mortality difference before or after 48 h [ 25 ] . There is
time to stabilize the patient, optimize medical conditions, and operate when conve-
nient on that admission.
If volvulus presents during the fi rst trimester of pregnancy, nonoperative de-rota-
tion should be carried out with a view to deferring surgery to the second trimester in
recurrent cases. If it presents in the third trimester, surgery should be deferred if
possible until after delivery [ 4 ] .
31.17 Is Bowel Preparation Necessary?
No. Bowel preparation is unnecessary for elective colonic surgery [ 26 ] , and volvu-
lus is no exception [ 27, 28 ] . Large series have been performed safely on unprepared
colon. On-table lavage is an option with gross loading; however, in most cases, there
is only fl atus in the colon. If excessive faecal loading is present following de-rota-
tion, bowel preparation can be given carefully in hospital – carefully, because prepa-
ration for colonoscopy has precipitated volvulus [ 29 ] .
31.18 What Operation Should Be Done Electively (Box 31.4 ) ?
There is no evidence that choice of operation affects survival. Operation should aim
to prevent recurrence. At least all of the sigmoid colon should be resected [ 6, 16, 20,
24, 30, 31 ] . Sigmoid colectomy can give good results particularly in able-bodied
patients. Advocates of total colectomy cite a recurrence rate of 14–37% with sigmoid
colectomy and anastomosis and a 20% recurrence rate for sigmoid colectomy and
459
31 Colon ic Volvulus
stoma [ 15, 32 ] . However, if there is no preoperative evidence of megacolon, the
recurrence rate after sigmoid colectomy is only 6% [ 10 ] . If there is proximal, mega-
colon recurrence increases up to 81% [ 32 ] . Therefore, in the presence of proximal
megacolon, subtotal colectomy is the operation of choice (age, frailty, and sphincter
function allowing).
Although some report higher mortality rates with anastomosis, this is not the norm.
Where there are no complications and the standard prerequisites for safe anastomosis
are met, a single-stage resection and primary anastomosis is safe with mortality in
single fi gures despite the patient population [ 1, 3, 6, 11, 16, 18, 28, 33 ] . Many of these
results were obtained without the benefi t of modern perioperative care. In selected
patients, it is possible to achieve zero leaks and zero mortality. Adding a proximal
blowhole colostomy above an anastomosis for volvulus has shown no benefi t.
31.19 Laparoscopic Versus Open Versus No Incision
Laparoscopic surgery and laparoscopically assisted surgery have been reported with
success. A high mortality (11%) and major complication rate (21%) was described
in a relatively young (median age 64 years) group undergoing laparoscopic resection
and primary anastomosis. However, this appears related to small study size and actu-
ally only represents one death [ 34 ] . Laparoscopic surgery faces competition from
resection via minilaparotomy in this group. The need for very little mobilization and
a large utility incision because of bowel size negates some of the benefi ts of laparos-
copy. The excessive colonic mobility can make resection so easy that Hartmann’s
procedure has been performed through only the trephine colostomy wound [ 35 ] .
31.20 Is There a Role for Nonresection Operative Procedures?
The short answer is no. Understanding the results of pexy procedures is hampered
by study size and short follow-up, but mortality ranges from 0% to 27% [ 8, 21, 23 ]
and recurrence from 0% to 50% [ 3, 8– 10, 13, 15– 17, 20, 21, 23, 30 ] . Therefore,
recurrence and mortality rates appear similar or worse than for resection [ 3 ] .
Operative tube sigmoidostomy has been successful in small series. These proce-
dures may have had a place for very high-risk patients in the past, but pexy can now
be achieved endoscopically rendering them obsolete in the UK.
Box 31.4: What Operation Should Be Done Electively?
Normal proximal colon = sigmoid colectomy
Proximal megacolon = subtotal colectomy
460
L.M. Hunt
31.21 What Is the Role of Percutaneous Endoscopic
Colostomy (PEC)?
PEC is an alternative to surgery in unfi t patients, preventing recurrence while in situ
[ 36– 38 ] . Mortality is high, but much of this is due to comorbidity [ 36, 37 ] . Infections
and dislodgements can cause morbidity and death. However, PEC is safe and effec-
tive with antibiotic cover, careful postoperative observation, and an acceptance of
bumper removal where needed. Early bumper removal results in recurrence in
37.5% of patients [ 38 ] , but later removal does not necessarily give a bad outcome.
NICE has approved PEC for recurrent volvulus if adequate audit processes are in
place.
A role for PEC as “a bridge to surgery” has been mooted [ 36 ] . However, the evidence
supports same admission surgery and simple endoscopic de-rotation acts as the neces-
sary bridge to surgery. PEC may have a role in cases where a delay in operation is antici-
pated, e.g., a myocardial infarction at presentation. There is no evidence for or against
PEC in this situation, and each case should be considered on its merits (Fig. 31.3 ).
31.22 Caecal Volvulus
The management of caecal volvulus is not controversial. Most are caused by axial
torsion of the caecum and ascending colon along its longitudinal axis. This rapidly
leads to fatal closed loop obstruction if not treated. Previous surgery, adhesions,
gastric banding, pelvic masses, and pregnancy are all occasional predisposing
factors. Most patients are reasonably fi t, and the presenting age is commonly
30–60 years. See Box 31.5 for radiological features.
19 patients unfit for
surgery
7 minor
complications
bleed 2, infection 4
8 died other causes
1 tube migration
peritonitis
death
7 PEC bumpers removed
at patient’s request @ 5 -
26 months
1 technical failure
6 no recurrence
1 recurrent volvulus repeat
PEC good result
2 in situ
no recurrence
Fig. 31.3 Results of prospective audit of PEC with median follow-up of 35 months (minimum
21 months) (Baraza et al. [
36 ] )
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