Page 16 - World Association of Laparoscopic Surgeons - Journal

Srijan Malla

Direct causes of Laparoscopic Biliary Injuries
Misidentification Errors

The most serious injuries are known to be caused by
misidentification of anatomy. It has been suggested that the
commonest cause of common bile duct injury is
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misidentification of biliary anatomy (70-80%). There are
two main types of misidentification. In the first scenario,
the common duct is mistaken for the cystic duct, and is
occluded and divided. Subsequently, the bile duct must be
Figs 1A to E5: Classification of laparoscopic injuries to the divided again later in the dissection during removal of
biliary tract 2
gallbladder, usually reported to as a ‘second cystic duct’ or
‘accessory duct’. An E1 to E4 injury results, depending on
as surgeons progressed beyond the learning curve.
the level of the second biliary tree division. Such injuries
However, more than 20 years after the introduction of the
are often associated with right hepatic arterial injuries which
procedure, with dramatic advancement in training and
may lead to torrential bleeding followed by conversion or
technology, there is still no evidence of any remarkable 13
may simply be an unrecognized occlusion of the artery.
improvement. Hence, other factors besides the inexperience
A second misidentification injury involves the aberrant
have to be considered. Although most injuries occur within
right hepatic duct, present in 2% of patients. The segment
the surgeon’s first 100 laparoscopic cholecystectomies, one-
of the aberrant right hepatic duct lying between its junction
third happen after the surgeon has performed more than
with the cystic duct and the point at which it joins the
200 showing that it is more than inexperience that leads to
common hepatic is misidentified as the cystic duct. Hence,
bile duct injury. 4
the surgeon unknowingly clips and cuts out this segment.
For removal of the gallbladder, the aberrant duct gets cut
Disease Severity
again, but at a higher level.
Severity of the underlying disease process has been proved The direction of traction of the gallbladder has been
to be an important risk factor. As in its open counterpart, known to contribute to the appearance that the common
biliary injuries are more likely to occur during difficult bile duct is the cystic duct and this can lead to the
laparoscopic cholecystectomies. 9 Laparoscopic chole- misidentification injury. When the pouch of Hartmann is
cystectomy performed for acute cholecystitis has a three pulled superiorly instead of laterally, the cystic and common
times more likelihood of causing a biliary injury than an bile ducts are aligned and appear as a single structure. 14
elective laparoscopic case, compared with a two-fold This deception is more common when the following factors
increased incidence in open cholecystectomy for acute are present—a short cystic duct, a large stone in the pouch
10
cholecystitis. Ooi et al reported a retrospective review of of Hartmann and severe, acute and chronic inflammation.
4,445 laparoscopic cholecystectomies with 19 biliary Mirizzi’s syndrome, in which the gallbladder communicates
injuries (0.43%). They found that inflammation at Calot’s directly with the common bile duct following recurrent
triangle was an important associated factor for injury. 11 inflammation, is a common cause for error. Misidentification
Other mentioned risk factors include old age and male may lead to injury of the bile duct even without division or
clipping, because extensive dissection can lead to
gender.
devascularization of the bile duct which present later as a
Anomalous Anatomy stricture.

As in any biliary surgery, this is a common cause of error, Technical Errors
especially in laparoscopic surgery. The aberrant right hepatic
Failure to occlude the cystic duct securely: Closure of cystic
duct anomaly is the most common problem leading to an
duct is usually done by clips, which remains unreliable if
injury. Injury to aberrant right hepatic ducts during
not applied correctly, as opposed to ligatures in open
laparoscopic cholecystectomy has been reported in various
studies. 12 However more often, such injuries are surgery. Clips may ‘scissor’ during application, resulting
in faulty closure or be loosened by subsequent dissection.
underreported as occlusion of an aberrant duct may remain
asymptomatic. Such aberrant ducts seem especially Too deep dissection on the liver bed: Injury to ducts in the
vulnerable during laparoscopic cholecystectomy. 2 liver bed is due to dissection in too deep a plane while

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