Introduction

ile duct injury (BDI) in laparoscopic cholecystectomy (LC) is characterized by high location at the porta hepatis and extensive thermal coagulation necrosis. Numerous investigations have demonstrated that long-term outcome of bile duct reconstruction is associated with not only the types of injury but also the timing of repair.^[1] More satisfactory results would be made by one-stage repair after immediate intraoperative diagnosis of BDI. However, retrospective analyses showed that more than half of BDIs had not been identified during the original LC.^[2] Among 9800 consecutive LCs performed in our hospital, a total of 9 cases of BDI were documented and 4 of them were recognized in traoperatively with simple non-Image methods. The aim of this study was to evaluate the role of simple non-Image techniques in intraoperative diagnosis of BDI. Also, the factors leading to misdiagnosis were analyzed.

Methods

A total of 9800 LCs were performed in our hospital from September 1991 to September 2001, during which 9 patients with BDI were found (7 were female and 2 were male, aged 30-72 years old). The original LC resulting in these BDIs was selective. Preoperative indications for LC included Polyps of the gallbladder in 1 patient and gallstones in 8.

Image techniques for prevention or diagnosis of BDI such as laparoscopic intraoperative cholangiography (LIOC) or laparoscopic ultrasonography were not used in all the 9 patients during the original LC. Uncommon or unexpected findings, for instance, marked retraction of the cystic duct stump (the common bile duct stump) down to the duodenum, intraoperative bile leakage from the porta hepatis, and abnormality of the removed gallbladder were considered as the indicators for diagnosis of BDI.

Results

BDI in 4 (44.4%) of the 9 patients was recognized during the original LC and immediately converted to laparotomy because of marked intraoperative re traction of the “cystic duct” stump down to the duodenum, bile leakage from the porta hepatis, and presence of the mucosal patch attached to the “cystic duct” stump of the removed gallbladder. According to the postoperative development of jaundice and/or bile peritonitis in other 5 patients, BDI was suspected and finally confirmed in delayed open reoperation 4-30 days after the original LC. The types of BDI consisted of transection of the common bile duct in 2 patients, partial clipping of the common hepatic duct (CHD) and resultant wall necrosis in 1, defect of the anterior wall of the extrahepatic bile duct in 3, and segmental defect of the extrahepatic bile duct in 3. Eight BDIs were repaired by Roux-en-Y hepaticojejunostomy and 1 was repaired by end-to-end anastomosis. Of 5 misdiagnosed BDIs, 3 received second hepaticojejunostomy 2-5 years after initial Roux-en-Y reconstruction for anastomotic stricture. After one-stage repair, 4 patients with intraoperatively recognized BDI were followed up for 6-58 months without biliary obstruction.

Discussion

Since the advent of LC, attention has been focused on its relatively higher morbidity of BDI. Many studies have been carried out on prevention of BDI during LC, but the BDI rate of LC is higher than that of open cholecystectomy. The BDI rate is definitely related to the leaning curve, but BDI cannot be solely attributed to the effect of the leaning curve.^[3] Carroll and colleagues^[2] found that about 10% of BDIs were made by operators who had completed more than 100 cases of LC. In this group, the la test BDI was made by the operator with the experience in over 2000 cases of LC. LIOC as a standard technique For avoidance of BDI has not been widely accepted as a routine procedure because of its time-consuming and cost-effectiveness. As for selective LIOC, whether the present LC is indicated for LIOC is frequently hard to be determined. In this group, BDI happened in 5 “uncomplicated” LCs and Unfortunately LIOC was omitted. In other 4 complicated cases, LIOC was not at tempted as well because of unaccepted regional anatomy of the cystic duct. Additionally, several investigations^{[2, 4]} have shown that BDI could still occur in the patients who had undergone LIOC. Since the inherent drawbacks of LC such as effects of the leaning curve, tactile loss, two dimensional operative field cannot be overcome in the predictable future, theoretically, BDI would be difficult to be totally avoided. The relationship between the timing of BDI repairment and long-term outcome of bile duct reconstruction indicates that sufficient attention should be paid to intraoperative diagnosis of BDI in each case of LC. The diagnosis of BDI should be at tempted from the commence of dissection of the Calot triangle to the end of the procedure. When BDI occurs, the most frequently utilized LIOC via the cystic duct is technically difficult or even impossible. Simple non-image techniques are feasible for intraoperative diagnosis of BDI, in which some uncommon or unexpected Phenomena in the operative field can be observed. These findings comprise the basis of non-Image diagnosis of BDI.

Misidentification of the common bile duct as the cystic duct is a common cause of BDI.^{[5, 6]} Transection of the misidentified common bile duct with or without subsequent transection of the common hepatic duct is a classic BDI in LC.^[6] During dissection of the Calot triangle and cystic duct, pulling the infundibulum upward and laterally is a necessary maneuver. Traction caused by this maneuver would make the major extrahepatic bile duct extend like a lengthened elastic. Transection of the common bile duct will interrupt the continuity of the extrahepatic bile duct. As a result, the distal segment of the common bile duct would no longer be suspended by the proximal bile duct and would be retracted markedly down to the duodenum. Distinctively, transection of the real cystic duct would not interrupt the continuity of the extrahepatic bile duct and the cystic duct stump would not be significantly retracted to the duodenum. Whenever the distal “cystic duct” stump markedly retracted down to the duodenum, operators should consider the occurrence of BDI. Had the common bile duct been misidentified as the cystic duct and divided, the space interior to the extrahepatic bile duct would have been misinterpreted as the Calot triangle. Blind further dissection in the “ triangle” may lead to injury to the common hepatic duct and segmental defect of the extrahepatic bile duct. Under this circumstance, immediate confirmation is critical to avoidance of more severe BDI. Directly converted laparotomy is indicated when mistaken transection of the common bile duct cannot be excluded. In one of our 9 cases of BDI, obvious re traction of the “cystic duct” distal stump alarmed the operators. Converted laparotomy prevented further injury to the extrahepatic bile duct. In another case, Similar re traction of the “cystic duct” stump was also observed and BDI was considered. Unfortunately, further dissection in the triangle resulted in serious segmental defect of the extrahepatic bile duct.

Bile leakage is relatively easy to find. Its mechanisms relevant to BDI differ. First, before clipping and dividing the CD, hook-shaped cautery or sharp-tipped dissector tears the common hepatic duct in dissecting the Calot triangle. Second, when the cystic duct has been correctly freed and divided, the common hepatic duct wall closely adhesive to the superointernal border of the infundibulum is lacerated or thermally injured during subsequent dissection up to the proximal infundibulum. Third, when the CBD is mistakenly divided as the cystic duct, the common hepatic duct is transected highly at the level of the porta hepatis subsequently. The last one is the most serious circumstance under which bile leakage comes nearly always from the porta hepatis because of the retracting backward of common hepatic duct distal stump. Bile leakage, especially in the course of dissection of the triangle, is usually a risky and reliable signal for BDI. Any bile leakage should be thoroughly irrigated and sucked. Bile leakage should be traced painstakingly. When it is not confirmed to originate from the ruptured gallbladder, the unsatisfactorily clipped cystic duct stump or the divided accessory bile duct, LC should be replaced by laparotomy without any hesitation. Arbitrary attribution of bile leakage to laceration of the gallbladder or tearing of the distal cystic duct may lead to misdiagnosis of BDI. Reviews of the background of the original LCs suggested that bile leakage had been observed in 3 cases. Subsequent to division of the “systic duct”, bile leakage from the porta hepatis was noted in 2 cases during dissection of the superointernal border of the infundibulum. Segmental defect of the extrahepatic bile duct was detected in the 2 cases at the time of converted laparotomy. It is a Pity that, in a misdiagnosed case, bile leakage was misinterpreted as one coming from the lacerated gallbladder and did not at tract the attention of the operators. Bile leakage was overshadowed by blood oozing in late dissection.

Under some circumstances, bile leakage is not readily to be detected, when considerable blood oozing piled up in an operative field. A large quantity of bile juice drained out from the abdominal cavity was documented in one case of our BDI series on the first postoperative day. The amount of the drained bile juice did not decrease in a week. Finally, bile leakage was found to originate from the common hepatic duct stump in laparotomic exploration two weeks after the original LC. Review of the backgrounds of the original LC indicated that bile leakage had been overshadowed by intraoperative hemorrhage. Had bile leakage been detected in the original LC, BDI would have been diagnosed in this case. Therefore, prior to completion of LC, ex traction of blood oozing piling up in the subhepatic space and close observation of the operative field are critical to final recognition of bile leakage and its origination.

A few BDIs occur without bile leakage because the common bile duct is misjudged and mistakenly divided as the cystic duct, while the common hepatic duct is misidentified as fiber bundle or the cystic vessel and transected between misplaced clips or the extrahepatic bile duct thermally injured but not ruptured yet. Without bile leakage, LC would be a clean procedure, in which BDI is extremely easy to be misdiagnosed. Even reviewing video tape of the original LC could not find any problem. Four of our five misdiagnosed BDI cases were found in a relatively clean LC. Bile leakage in another case was noted postoperatively rather than intraoperatively. In these cases, careful inspection of the removed gallbladder may be an effective way to avoid misdiagnosis. In normally removed gallbladder, solitary mucosal patch should not be found around the clipped cystic duct stump. When the mucosal patch attaching to the clipped “cystic duct” stump is found, BDI must be suspected in the present LC. The solitary mucosal patch is actually the overlaid mucosa of the divided common hepatic duct distal end, whereas the clipped “cystic duct” stump is actually the mistakenly clipped and transected common bile duct proximal stump. Removing the clips at the “cystic duct” stump, inspectors could find the mucosal patch in continuity with the mucosa of the “cystic duct”. The patch may be as small as a bean and can only be recognized by close observation. Two cases of BDI were suspected and converted to laparotomy because of bile leakage found intraoperatively. Before conversion, their removed gallbladders were thoroughly examined. Without exception, mucosal patch attaching to the “cystic duct” was detected in the two cases. The removed specimens were not inspected in the other 5 misdiagnosed cases. immediate examination of the removed gallbladder has been a routine step of LC in our hospital.

Thermally injured bile duct which has not yet ruptured is hard to be identified. It is hypothesized that either LIOC or non-image approach cannot readily recognize the lesion. Based on postoperative development of bile peritonitis caused by thermal injury to the CHD, we found a case of undetected BDI 7 days after original LC, during which, however, no abnormalities were observed.

BDI resulted from misplacement of clip and resultant necrosis was documented in one of our cases. Because of neither bile leakage nor abnormal findings in the removed gallbladder, this type of BDI is difficult to be diagnosed intraoperatively by non-image approach. Hopefully, laparoscopic ultrasonography may facilitate detection of this type of BDI as claimed by Birth and colleagues.^[7]

In summary, our lessons from this series demonstrated that attention should be paid to the following aspects in prevention of misdiagnosis of BDI. First, BDI may occur in many circumstances. Even a seemingly uncomplicated LC performed by an experienced operator may result in BDI. Therefore, confirming whether BDI has occurred should be listed as a standard step for any case of LC. Our experience indicated that had attention been paid, simple non-image techniques for intraoperative diagnosis of most BDIs would be feasible and reliable. Second, to some extent, the cystic duct stump markedly retracting down to the duodenum may indicate a mistaken division of the common bile duct. Third, intraoperative bile leakage is usually a risky signal for BDI. Recognizing bile leakage and tracing its origination will definitely facilitate diagnosis of BDI. Finally immediately careful inspection of the removed gallbladder is a reliable and effective method to prevent misdiagnosis of BDI.

References

1 Berci G. Complications of laparoscopic cholecystectomy. Surg Endosc 1998;12:291-293.

2 Carroll BJ, Birth M, Phllips EH. Common bile duct injuries during laparoscopic cholecystectomy that result in litigation. Surg Endosc 1998;12:310-314.

3 Calvet J, Sabater L, Camps B. Bile duct injury during laparoscopic cholecystectomy. Myth or truth of the leaning curve? Surg Endosc 2000;14:608-611.

4 Mck MJ. Intraoperative cholangiography and bile duct injury in laparoscopic cholecystectomy. Surg Endosc 2000;14:94.

5 Davidoff AM, Pappast N, Murray EA, et al. Mechanism of major biliary injury during laparoscopic cholecystectomy. Ann Surg 1992;215:196-202.

6 Birth M, Carroll BJ, Delinikolas K, et al. Recognition of laparoscopic bile duct injuries by intraoperative ultrasonography. Surg Endosc 1996;10:794-797.

(Accepted August 9, 2001)