Primer on
Laparoscopic Gallbladder Surgery and Injury to the Biliary Tract
By:
Thomas
T. Dunbar, Esq.
This medico-legal
article explains the laparoscopic gall bladder surgery and the proper
technique to avoid injury. An injury can be chronic and devastating.
Both laymen and legal practitioners should be aware of the future risks
prior to resolving a claim of medical negligence causing bile duct injury.
(A glossary of terms can be found at the end of this article.)
I. INTRODUCTION -
ANATOMY
The biliary ducts carry
bile from the liver to the small intestine. Bile aids in the digestion
of fatty foods. The biliary tract begins as the left lobe duct and the
right lobe duct which descend from the liver. These two liver ducts
form at their bifurcation the common hepatic duct. As the hepatic duct
descends toward the small intestine, the cystic duct which leads from
the gallbladder joins the hepatic duct to form the common bile duct.
The common bile duct descends into the small intestine. The ampulla
of vater is the sphincter of tissue that controls the flow of bile from
the common bile duct into the small intestine.
Cholecystectomy is the
removal of the gallbladder due typically to gallstones or sludge formation.
Most often a cholecystectomy is an elective or planned procedure though
emergency cases occur. The gallbladder is removed surgically by clipping
and transecting the cystic duct and the cystic artery so as to allow
the gallbladder to be removed. The gallbladder is not a vital organ
and if gallstones or sludge formation have occurred, it can be readily
removed without a change in lifestyle or liver or biliary tract function.
Earlier, a surgical procedure
was used to open the patient's abdomen and the biliary tract was examined
in a traditional manner by the surgeon. In the late 1980s, laparoscopic
surgery became the method of choice to remove the gallbladder. Laparoscopic
surgery was touted as causing less pain to the patient and a shorter
recuperative period.
II. LAPAROSCOPIC TECHNIQUE
Preceding removal of the
gallbladder during laparoscopic surgery, "trocars" are introduced
into the patient's abdomen. Trocars are sharply pointed instruments
used to puncture a cavity so as to remove fluid, blood, or introduce
laparoscopic instruments. The trocars allow for lighting, video camera
illustration, surgical instruments and carbon dioxide insufflation.
The abdomen is insufflated with carbon dioxide initially and video camera
and surgical instruments are used to scan the abdomen for any abnormalities.
The liver is lifted and the gallbladder is exposed. The gallbladder
is grasped and a process of meticulous dissection begins to remove tissue
and/or adhesions from the gallbladder and cystic duct so that accurate
identification of the anatomy occurs. The better practice is to pull
the base of the gallbladder to the patient's right so that the cystic
duct is perpendicular to the common bile duct. When the base of the
gallbladder is not pulled to the patient's right side, oftentimes the
cystic duct aligns parallel to the common bile duct which can lead to
misidentification. Particularly, a short cystic duct can cause misidentification
of the anatomy, but should not since meticulous dissection will reveal
the junction between the gallbladder and the cystic duct.
Because there are variations
in the biliary anatomy, most surgeons agree that the safest practice
is to perform a cholangiogram before a transection of any duct. A cholangiogram
is a test where dye is introduced into the biliary system and outlines
the system so that the anatomy is more readily identified. A cholangiogram
is a safeguard for the patient. It confirms that the surgeon has properly
identified the anatomy and also the lack of any ductal injury. It also
confirms that a gallstone is not obstructing the biliary tract thereby
eliminating a possible problem requiring re-invasive treatment at a
later time.
Many surgeons in active
practice in the late 1980s went through training which included early
monitoring at their hospitals by qualified and experienced laparoscopic
surgeons. At the same time, medical students began receiving laparoscopic
training in medical school and were qualified prior to graduation
Surgical journals reveal
that many iatrogenic ("physician-caused") injuries during
laparoscopic cholecystectomies are due to lack of experience. The Southern
Surgeon's Club reported that the new laparoscopic technique resulted
in a learning period. The learning curve reflected a higher incidence
of bile duct injury. The Southern Surgeon's Club's study found that
within the first 13 cases of any participant's experience, the bile
duct injury rate was 2.2%, compared with 0.1% after the 13th
case. During the initial 12 - 13 procedures the surgeon is on his "learning
curve". Another cause for injuries is the surgeon's overconfidence
resulting in failure to meticulously dissect and conclusively identify
the biliary anatomy prior to transection.
III. INJURY AND REPAIR
EFFORTS
Injuries include clipping
and/or cutting of common bile duct, hepatic duct, or other anatomy.
Clipping of the improper duct may prevent the flow of bile which backs
up in the liver leading to jaundice. If the hepatic/common duct is cut,
bile will leak into the abdominal cavity resulting in possible infection.
If the hepatic duct/ common duct is transected it may be surgically
repaired at the time of injury with no resulting complications. If not
identified and repaired within a short time, the patient may face a
lifetime of chronic troubles. Since the biliary ducts do not have profuse
blood circulation, scar tissue may form at the site of a repair causing
a stricture or narrowing that blocks the flow of bile. The stricture
may be repaired (or managed) via a catheter needle introduced (through
the skin) into the liver. Then a deflated balloon is guided down into
the stricture where it is inflated to open up the stricture (as occurs
in angioplasty). The risks of significant bleeding, infection and other
complications of the balloon dilatation procedure are approximately
11%. Further, repeated balloon dilatations efforts and other necessary
gastrointestinal studies increase the risk of scar tissue within the
ductal anatomy at the anastomosis and at other locations where friction
occurs. A second option that may be required to repair a stricture is
re-operation and re-attachment of the remaining hepatic duct with a
loop of the bowel. A Roux-en-Y hepaticojejunostomy is a surgical procedure
often used to attempt to repair bile duct lesions or injuries high (towards
the liver) on the bile duct. A hepaticojejunostomy involves removing
a 8-10 inch loop of bowel from the small intestine, suturing one end
closed, suturing a top portion of the loop to the remaining bile duct,
and re-suturing the lower end into the intestine. Strictures also occur
at the site of the anastomosis or the location where the remaining duct
is sutured to the loop of intestine. A stricture at the anastomosis
or connection between the biliary duct and the bowel loop may require
continued management via balloon dilatation. This repair may fail requiring
re-attachment at a higher level of the biliary tree. Ultimately, a patient
is transformed via a biliary injury from a relatively healthy individual
to a patient who, at a minimum, must have her liver enzymes regularly
monitored for possible obstruction. Cholangitis (infection), liver damage,
liver transplantation are possibilities.
Injuries to the biliary
tract can have a devastating impact on a patient's life. Injuries that
are discovered post-operatively should be referred to a specialized
center with expertise in hepatobiliary surgery because the first attempt
at repair is critical. Studies show there is an increased risk of stricturing
if an initial stricture occurs. The mortality risks also increase if
the first repair is not successful.
When a stricture occurs
following an injury, one effect is "back flow" pressure in
the liver since the bile no longer flows to the intestine. If this pressure
is not relieved, liver damage can result. One of the effects of prolonged
stricture formation is dilation of the intra-hepatic ducts. (The extra-hepatic
ducts are the ducts that flow out of the liver towards the intestine.
The intra-hepatic ducts are the ducts within the liver.)
Cholangitis is infection
or inflammation of the bile ducts. Since the ampulla of vater no longer
is present in the injured patient, the sphincter of tissue that normally
control the flow of bile from the common bile duct to the small intestine
is no longer present. Therefore, the bacteria and other matter present
in the small intestine can flow up the previously "sterile"
biliary duct to cause infection possibly extending into the liver. Antibiotics
are used to treat the cholangitis which is then usually resolved but
may re-appear intermittently. Severe cases of cholangitis can be life-threatening
particularly after several episodes due to the effect on the ducts and
possibly the liver.
IV. STANDARD OF PRACTICE
The Society of American
Gastrointestinal Endoscopic Surgeons (hereinafter "SAGES")
sets forth well-established principles for the prevention of injury
during laparoscopic biliary tract surgery:
-
the cystic duct should
be identified at its junction with the gallbladder;
-
traction on the gallbladder
infundibulum (middle to lower portion of organ) should be lateral
rather than cephalad (towards the "head");
-
meticulous dissection
of the cystic duct and cystic artery is essential;
-
gallbladder holes should
be closed to prevent loss of stones;
-
the surgeon should
not hesitate to convert to an open operation for technical difficulties,
anatomic uncertainties or anatomic anomalies, especially in cases
of acute cholecystitis (infection of the gallbladder);
-
liberal use of operative
cholangiography is desirable to discover surgically important anomalies,
clarify difficult anatomy and to detect unsuspected common bile
duct stones; all energy sources (electro-cautery or laser which
is used to dissect gallbladder off liver bed) can cause injury.
An injury may be difficult to detect immediately.
Correct dissection exposes
the cystic artery and the entire gallbladder infundibulum but not the
common bile duct. The steps of dissection that will avoid confusing
the common bile duct for the cystic duct are:
- retraction of the infundibulum laterally;
- initiation of dissection on the gallbladder
(dissection should begin on the gallbladder and proceed along the
cystic duct towards the common bile duct rather than vice-versa);
- opening up all folds in the gallbladder;
- stopping medial (towards the patient's
middle) dissection when a sufficient portion of the cystic duct has
been cleaned for cholangiography and clipping; and
- application of the first clip to the
base of the pedunculated gallbladder where it begins to taper to its
stalk (where cystic duct begins).
Because the cystic duct
and cystic artery are the structures to be divided, it is these structures
only that must be conclusively identified in every laparoscopic cholecystectomy.
Accordingly, the cystic duct and artery should not be clipped or cut
until conclusively identified. To achieve conclusive identification,
Calot's Triangle must be dissected free of fat, fibrous and areolar
tissue and the lower end of the gallbladder dissected off of the liver
bed. (The latter is an essential measure that precludes the possibility
of injury to an aberrant duct.) At the completed dissection, there should
only two structures seen to be entering the gallbladder, and the bottom
of the liver bed should be visible. While it is not necessary to see
the common duct, it is at this point that the surgeon has achieved the
critical view of safety and the cystic structures may be occluded because
they have been conclusively identified. Failure to achieve the critical
view of safety because of difficulty of dissection as a result of inflammation
or any other cause is an absolute indication for cholangiography or
conversion to open cholecystectomy to define ductal anatomy.
If an injury is recognized
early, it can be repaired by the surgeon and the patient stands a much
greater chance of no resulting complications. Therefore, the standard
of practice requires the surgeon to search for potential injuries prior
to completing the surgery. The omission of cholangiography increases
the odds of an injury failing to be recognized.
After a repair surgery,
stricturing (an abnormal narrowing) and re-stricturing occurs unfortunately.
Some studies reflect that only 10-28% patients undergoing hepaticojejunostomy
in these circumstances experience a stricture of the ductal anatomy.
However, these studies arguably include "selection bias" of
the reporting physicians in choosing their patients and the studies
do not involve long periods of patient history review. Further, re-stricturing
is more likely after an initial stricture. Strictures may occur as late
as 20 years after the initial repair surgery. A minimum of 5-7 years
is required in follow-up of the patient before a patient's chances of
stricture following a repair surgery diminish significantly.
In one patient's case presently
in litigation, the repair surgeon wrote in the Operative Notes that
there was a 90% chance that the patient would completely recover from
the repair surgery. Four months later, the patient experienced a stricture
of the anastomosis or repair site, cholangitis, a balloon dilatation
sequence involving two dilatations and repeated episodes of an apparent
continuing peptic ulcer. Another result of the hepaticojejunostomy repair
is that stomach acids no longer neutralize the bile as before. Rather,
the bile acids directly flow into the intestinal loop and this can cause
an ulcer as the acids inflame the intestinal tissue.
Another client's experience
began in 1990 when her bile duct was divided during laparoscopic cholecystectomy.
A cholangiogram was not performed and the injury was not diagnosed nor
repaired until approximately 14 days later. This patient's management
has included two major surgeries (re-attachments) and numerous balloon
dilatations of recurrent stricture (all within three years).
Therefore, the author suggests
that an attorney practicing in this field of medical malpractice should
not resolve his or her client's case without an understanding of the
significant and chronic risks facing the injured patient.
For additional information
contact:
Thomas T. Dunbar
Post Office Box 1230
Jackson, MS 39215
Phone: (601) 949-8900
Fax: (601) 949-8911
E-Mail: tdunbar@misnet.com
Glossary of
Terms:
aberrant: abnormal;
usually applied to a blood vessel or nerve that does not follow its
normal course
ampulla of vater:
the dilated part of the common bile duct where it is joined by the pancreatic
duct
anastomosis: a
communication between two vessels or ducts without any intervening capillary
network
anomalies: any
deviations from the normal
areolar: binds
the skin to underlying muscles and forms a link between organs while
allowing a high degree of relative movement
bifurcation: the
point at which division into two branches occurs
Calot's Triangle:
triangle exposed upon dissection and retraction of gallbladder; it is
formed by alignment of cystic duct, cystic artery and common duct
catheter: a flexible
tube for insertion into a narrow opening so that fluids or instruments
may be introduced or removed
cholangiography:
X-ray examination of the bile ducts, used to demonstrate the site and
nature of any obstruction to the ducts or to show the presence of stones
within them
cholangitis: inflammation
of the bile ducts which usually occurs when the ducts are obstructed,
especially by stones, or after operations on the bile ducts
cholecystectomy:
surgical removal of the gallbladder
common bile duct:
the duct that conveys bile from the liver; it is formed when the hepatic
duct and cystic duct join
cystic artery:
the artery supplying blood to the gallbladder
cystic duct: the
duct connecting the gallbladder to the common bile duct
dilatation: the
state of being distended or stretched
dissection: the
cutting of tissues in an orderly manner so as to distinguish and separate
anatomical parts from one another
gallbladder: a
hollow, pear-shaped organ located beneath the liver in the right upper
portion of the abdomen, it stores and concentrates bile
gallstones: stones
in the gallbladder
gastrointestinal:
relating to the stomach and intestines
hepaticojejunostomy:
operation attaching a loop of intestine directly to
ducts at base of liver;
a bypass of hepatic/common ducts
hepatobiliary:
referring to the liver, gall bladder and bile ducts
infundibulum: a
stalk or funnel-shaped structure; the portion of the gallbladder
near the cystic duct junction
insufflated: blow
a vapor or powder into a part of the body
jaundice: yellow
discoloration of the skin and eyes due to bile pigments in the blood
lateral: out to
the side, rather than toward the midline
medial: toward
the midline of the body, the opposite if lateral
pedunculated: attached
by a narrow stalk
retraction: the
pulling aside of a structure during surgery to afford the surgeon a
better view
sphincter: a ringlike
muscle which controls opening and closing of a bodily opening
stricture: an abnormal
narrowing
transection: the
cutting across
trocars: sharply
pointed surgical instruments used to puncture a cavity so as to remove
fluid, blood, or introduce laparoscopic instruments
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