Page 36 - World Association of Laparoscopic Surgeons - Journal
P. 36

Srijan Malla



























                  A                                           B
                 Figs 3A and B: (A) Critical view of safety (CVS) is seen from in front of the gallbladder as usually shown, (B) CVS is
                      seen with the gallbladder reflected to the left, so that a posterior view of the triangle of Calot is shown 22

          in the remaining where it was not obtained, conversion to  structure was delineated in all 52 patients studied using the
          open surgery was done. 22                           fluorescent imaging system. However, the cost involved is
             Another method of conclusive identification of cystic  a deterrent for widespread use. Similarly, Sari et al proposed
          structures is by routine intraoperative cholangiogram.  injecting methylene blue in the gallbladder after aspirating
          Several prospective studies have tried to evaluate the  the bile with a Varess needle before starting dissection. 27
          usefulness of IOC in preventing CBD injury. A meta-    To overcome the problem of anatomical orientation,
          analysis of 40 case series detailing 327,523 LCs and 405  before starting dissection, identification of fixed anatomical
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          major injuries was performed in 2002.  Rate of injury was  landmarks is helpful. Hugh recommends identifying
          halved in the routine IOC group (0.21%) as compared with  Rouviere’s sulcus as a fixed extrabiliary point ventral to
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          the selective group (0.43%). In addition, in the selective  the right portal pedicle.  Dissection ventral to this allows
          group, only 21.7% of CBD injuries were detected     a triangle of safe dissection when the gallbladder has been
          intraoperatively. Fletcher et al found that routine IOC  reflected cephalad. Extending this dissection as far as
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          reduced the incidence of injury.  The study method adjusted  possible up the gallbladder fossa both posteriorly and
          for confounding variables, such as age, sex, hospital type  anteriorly allows the hepatobiliary triangle to open out. This
          and severity of disease. One argument against       ensures no unexpected anatomy and confirms the correct
          cholangiography is, if the CBD is misidentified while an  anatomical position before any significant structure is
          IOC is being performed, the ductotomy created for   divided.
          placement of the IOC catheter is itself a CBD injury.  In cases of difficulties due to severe adhesion of the
          However, other studies suggest that the severity, but not  gallbladder to surrounding and severe fibrosis, some have
          the incidence of biliary injury is reduced by routine IOC.  advocated using laparoscopic subtotal cholecystectomy as
          Operative cholangiography is best at detecting      an alternative to conversion as equal difficulty in dissection
          misidentification of the common bile duct as the cystic duct  would be required in the open surgery as well. They claim
          and will prevent excisional injuries of bile ducts, if the  that conversion does not guarantee the avoidance of
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          cholangiogram is correctly interpreted. In an analysis of  inadvertent biliary or vascular injury.  Tian et al in 2009,
          252 bile duct injuries during cholecystectomy, Way et al  reported performing laparoscopic subtotal cholecystectomy
          reported that 43 IOCs demonstrated a bile duct injury, but  in 48 difficult cases out of 1558 laparoscopic cholecystec-
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          only nine were correctly interpreted at the time of  tomies without any serious bile duct injuries.
          operation. 25
                                                              Human Factors and Bile Duct Injury
             Recently, other techniques proposed to correctly identify
          biliary anatomy include the use of dyes. Ishizawa et al  Although thorough instruction in the principles of safe
          reported using fluorescent cholangiography technique using  surgical technique for cholecystectomy is essential, it may
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          the intravenous injection of indocyanine green.  The biliary  be equally important to develop new training strategies that
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