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to date , the management of concomitant gallbladder and common bile duct ( cbd ) stones is still controversial .
there are several approaches to the treatment of biliary lithiasis , including laparoscopic common bile duct exploration ( lcbde ) and pre- , intra- , or postoperative endoscopic retrograde cholangiopancreatography ( ercp ) . despite these multiple options and the improvement of minimally invasive techniques
, many surgeons still perform an open cbd exploration with external biliary drainage ( ebd ) .
the simultaneous laparoscopic treatment of cbd stones during laparoscopic cholecystectomy ( lc ) has demonstrated advantages when compared with other surgical approaches .
however , the laparoscopic exploration of the bile ducts requires the proper equipment as well as expertise in advanced surgical skills , such as bile duct suturing and stones extraction .
the removal of biliary stones can be achieved either through the cystic duct or by choledochotomy .
although both approaches are useful and have precise indications , the transcholedochal route has been associated with a higher morbidity rate , mainly related to the frequent use of a t - tube for biliary decompression . regarding this particular issue , the use of a transpapillary stent ( ts ) appears to be a valuable and safe alternative to avoid these complications with satisfactory outcomes .
the aim of this study was to analyze the morbidity , mortality , and outcomes between patients with biliary lithiasis who underwent lcbde and biliary stenting versus external biliary drainage .
the current report presents a single - institution retrospective analysis of a prospectively maintained database . between january 2007 and may 2012 ,
a total of 3700 consecutive patients underwent an lc to treat gallbladder lithiasis at the hospital italiano de buenos aires . in 356 ( 9.6% ) patients , choledocholithiasis was diagnosed or confirmed by routine intraoperative cholangiography ( ioc ) and were treated by an lcbde . in all of these patients ,
stone extraction was attempted , either transcystically or with transcholedochal exploration . in 48 ( 13% ) patients , either ts or ebd
was required for biliary decompression as a result of residual stones or reduced flow of contrast material into the duodenal lumen .
four trocars were used ( one 10-mm umbilical , one 5-mm epigastric , two 5-mm in the right flank ) . ioc was routinely used and performed through a cholangiography catheter into the cystic duct .
once the presence of biliary stones was confirmed , lcbde under fluoroscopic control was performed with the use of a web24 extraction basket ( cook medical , bloomington , indiana ) either through the cystic duct or by choledochotomy .
cbd junction were indications to perform a choledochotomy . for biliary decompression either ts or ebd
was considered depending on the operating surgeon 's experience , the availability of the material , the possibility of cannulating the ampulla with a wire guide , and the presence of residual stones . for transpapillary
stenting , a 7-fr plastic biliary stent was placed ( cotton - leung 79 , cook medical ) ( figure 1 ) .
if a choledochotomy had been performed , primary biliary closure consisted of interrupted 5 - 0 polydioxanone stitches ( pds ii , ethicon , somerville , new jersey ) with the intracorporeal knot - suturing technique . for ebd
, a t - tube was placed using the same surgical technique as the open approach . at the end of the procedure ,
an ioc was performed to certify a proper repair , ensure an appropriate positioning of the stent or the t - tube , and confirm the free flow of contrast into the duodenum ( figure 2 ) .
stay , daily clinical evaluation and laboratory tests were performed . after discharge , the patients were controlled every 3 months during the first year and annually thereafter ( with clinical evaluation and liver function tests done ) . according to the findings
the dindo - clavien classification was used to stratify the severity of complications . for comparison between treatment modality ,
the  test was used for categorical variables and the student t test was used for continuous variables .
analyses were performed using ncss software ( version 2007 , ncss kaysville , utah ) .
four trocars were used ( one 10-mm umbilical , one 5-mm epigastric , two 5-mm in the right flank ) . ioc was routinely used and performed through a cholangiography catheter into the cystic duct .
once the presence of biliary stones was confirmed , lcbde under fluoroscopic control was performed with the use of a web24 extraction basket ( cook medical , bloomington , indiana ) either through the cystic duct or by choledochotomy .
cbd junction were indications to perform a choledochotomy . for biliary decompression either ts or ebd
was considered depending on the operating surgeon 's experience , the availability of the material , the possibility of cannulating the ampulla with a wire guide , and the presence of residual stones . for transpapillary stenting ,
a 7-fr plastic biliary stent was placed ( cotton - leung 79 , cook medical ) ( figure 1 ) .
if a choledochotomy had been performed , primary biliary closure consisted of interrupted 5 - 0 polydioxanone stitches ( pds ii , ethicon , somerville , new jersey ) with the intracorporeal knot - suturing technique . for ebd
, a t - tube was placed using the same surgical technique as the open approach . at the end of the procedure ,
an ioc was performed to certify a proper repair , ensure an appropriate positioning of the stent or the t - tube , and confirm the free flow of contrast into the duodenum ( figure 2 ) .
after discharge , the patients were controlled every 3 months during the first year and annually thereafter ( with clinical evaluation and liver function tests done ) . according to the findings
during patients ' hospital stay , daily clinical evaluation and laboratory tests were performed . after discharge
, the patients were controlled every 3 months during the first year and annually thereafter ( with clinical evaluation and liver function tests done ) . according to the findings
for comparison between treatment modality , the  test was used for categorical variables and the student t test was used for continuous variables .
analyses were performed using ncss software ( version 2007 , ncss kaysville , utah ) .
of the 48 patients who comprised the study population , all underwent an lcbde without conversion to open surgery .
eighteen patients ( 37% ) underwent a transcystic stone extraction , and 30 patients ( 63% ) required a choledochotomy .
ts and ebd were placed in 35 ( 73% ) and 13 ( 27% ) patients , respectively ( figure 3 ) .
there were no statistically significant differences in epidemiological characteristics and preoperative factors ( table 1 ) .
regarding operative times , there were no statistically significant differences between both groups ( p=0.08 ) . however , postoperative complications were significantly higher ( p<.0001 ) in the group with an ebd ( table 2 ) .
overall morbidity in the ebd group was 38% ( 5 patients ) , with two patients developing acute pancreatitis , two developing cholangitis , and 1 presenting with an accidental displacement of the t - tube .
regarding the ts group , one patient presented with a biliary peritonitis in the immediate postoperative period that required reoperation . during laparoscopic exploration , an accessory duct of luschka
regarding hospital stay , the ts group presented a faster recovery than the ebd group ( table 3 ) .
epidemiological characteristics : preoperative factors postoperative complications media time of surgery , hospital stay , and removal of stent or drainage those patients in the ts group underwent a postoperative outpatient ercp for stent removal on average 4 weeks ( range , 1590 days ) after surgery , with successful cannulation and stent removal in all cases .
in addition , 7 patients ( 20% ) in this group presented with residual biliary lithiasis that was successfully treated during the same endoscopy . in patients with an ebd ,
a transcatheter cholangiography was performed 6 weeks ( range , 3070 days ) after surgery , which showed free contrast flow into the duodenum lumen without residual lithiasis in all patients , thus the drain was removed .
approximately 8% to 15% of the patients with symptomatic gallstones have simultaneous choledocholithiasis . historically , in patients with a preoperative diagnosis of cbd stones during the early laparoscopic era , a two - stage surgical approach ( ercp followed by lc ) was the preferred treatment for most surgeons .
cbd stones often escape notice in ordinary preoperative work - up for lc such as with liver function tests or ultrasonography , making preoperative diagnosis challenging .
alternatively , ercp has been associated with a morbidity of 7% to 15% and a cannulation failure rate ranging from 5% to 20% .
recent studies have demonstrated the advantages of the laparoscopic treatment of cbd stones in a single stage , with equivalent results to those of ercp .
moreover , the increasing adoption of ioc has brought the laparoscopic surgeon against the potential situation of having to deal with the presence of unsuspected choledocholithiasis .
currently , lcbde and stone extraction have become safe and valuable alternatives in the hands of skilled surgeons  either transcystically or through a choledochotomy . because of a lower complication rate , laparoscopic exploration through the cystic duct remains the access location of choice .
however , a low cystic duct  cbd junction and large ( 10 mm ) , multiple , or intrahepatic stones are indications to perform a choledochotomy . in 18 ( 37% )
patients in our series , the cbd exploration was achieved through the cystic duct , and 30 ( 63% ) patients underwent a choledochotomy .
an ebd was used for biliary decompression in less than half of the patients who had a choledochotomy performed .
ebd was a safe and effective method to prevent biliary leakage or to provide an effective biliary decompression in cases of incomplete stone removal after choledochotomy closure in the open cholecystectomy era . despite these advantages ,
t - tube  related complications were discussed for decades , with 15% to 28% morbidity either in the open or laparoscopic approach .
the most common complications described are postoperative cholangitis , accidental t - tube displacement , and biliary leakage after drainage removal .
recent literature suggests that laparoscopic endobiliary stents decrease postoperative t - tube  related complications , improving patient comfort and a promoting a faster recovery . in our series , the stent group had significantly fewer complications than the ebd group ( 2.8% vs 38% ) , which is consistent with the current literature .
in addition , those patients in the ebd group had two times longer hospital stays than those in the ts group , with discharges 3 and 6 days after surgery , respectively .
the main drawback of placing a ts after lcbde is the need for a second procedure ( ercp ) to remove the stent . in our series
, ercp was successfully performed in all patients in whom a transpapillary stent was placed , with the removal of the stent and stones extraction as a frequent associated procedure . in this particular
regard , the success rate of stone clearance after lcbde was 85% , which is similar to that of other authors .
the absence of cannulation failure in the ercp , an event that has been reported in as many as 20% of patients with cbd stones , is another advantage of the stenting group that should be taken into account to decide which strategy to use whenever biliary decompression is needed after cbde . despite the results and their statistical value
, our study presents some weaknesses because it is a retrospective study in a single institution .
because of this , we emphasize the need for randomized controlled trials to clarify and support our findings .
however , the excellent results obtained make this approach a safe and useful tool to treat the cbd stones .
it has lower morbidity and mortality rates , requires a shorter hospital stay , and gives the additional benefit of achieving a high rate of cbd cannulation and stone extraction with postoperative ercp , thus avoiding repeat surgical or endoscopic procedures to treat residual lithiasis .
background : to date , the management of common bile duct stones ( cbds ) is still controversial . 
 if laparoscopic exploration is performed and biliary decompression is needed after stone removal , the placement of a laparoscopic transpapillary stent shows promising results in avoiding t - tube  related complications.methods:between january 2007 and may 2012 , a series of 48 patients who underwent biliary decompression after laparoscopic common bile duct exploration ( lcbde ) to treat choledocholithiasis was retrospectively analyzed . 
 the results in patients with transpapillary stent placement ( ts=35 ) were compared with those who had an external biliary drainage ( ebd=13).results : lcbde and ts placement was achieved either by a choledochotomy or through the cystic duct . 
 there was no mortality in our series . 
 patients with an external biliary drainage ( ebd ) had more surgery - related complications ( p<.0001 ) and a longer hospital stay ( p=.03 ) . 
 postoperative ercp to remove the ts was successful in all cases.conclusion:laparoscopic ts is a safe method in the treatment of selected patients with cbd stones that can be achieved without having to perform a choledochotomy . because of the lower morbidity and the shorter hospital stay compared with ebd , it should be considered as a first approach whenever biliary decompression is needed after lcbde .