UvA-DARE (Digital Academic Repository) A journey to improve treatment outcome of laparoscopic cholecystectomy Donkervoort, S.C. Link to publication Citation for published version (APA): Donkervoort, S. C. (2018). A journey to improve treatment outcome of laparoscopic cholecystectomy General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (http://dare.uva.nl) Download date: 04 Sep 2018
CHAPTER 1 Conversion rate of laparoscopic cholecystectomy after endoscopic retrograde cholangiography in the treatment of choledocholithiasis: Does the time interval matter? 1 2 3 4 5 6 7 Surg Endosc. 2005 Jul;19(7):996-1001. De Vries A Donkervoort SC Van Geloven AA Pierik EG. 8 S
20 Chapter 1 Abstract Background: Preceding endoscopic retrograde cholangiography (ERC in patients with choledochocystolithiasis impedes laparoscopic cholecystectomy (LC) and increases risk of conversion. We studied the influence of time interval between ERC and LC on the course of LC. Methods: All patients treated for choledochocystolithiasis with ERC and LC during 1996 2001 were studied retrospectively, comparing the course of LC in three time interval groups; LC < 2, 2 6, and > 6 weeks after ERC. Primary outcomes: adhesions, bile duct injury, operating time, and conversion-rate. Results: Eighty-three patients were studied (group 1, n = 23; group 2, n = 15; group 3, n = 45). Adhesions, operation time, and bile duct damage did not significantly differ between the groups. The conversion rate in group 2 is significantly higher compared to group 1 (p = 0.027, OR 11 (1.13 106.8)) Conclusions: A higher conversion rate of LC is found 2 6 weeks after ERC compared to LC within 2 weeks. However, further research is needed to gain more reliable data on whether this is caused by timing.
Conversion rate of laparoscopic cholecystectomy after endoscopic retrograde cholangiography 21 In the treatment of choledochocystolithiasis, endoscopic retrograde cholangiography (ERC) is a well-established method to attain ductal clearance before a laparoscopic cholecystectomy (LC) is performed [4,5,13,20]. Although this management is widely accepted by many authors, the need for a cholecystectomy after ERC is still somewhat controversial. [7,15,16,18,21] Some studies showed no benefit of an elective cholecystectomy and suggest a wait-and-see policy [9,11,22]. The first prospective randomized trial, however, done to compare both strategies, showed such a high rate of recurrent biliary events in the wait-and-see group that an elective laparoscopic cholecystectomy after ERC seems justified [2]. In gallstone-induced acute pancreatitis, surgeons agree that prompt cholecystectomy is the norm as the risk of recurrent pancreatitis is significantly reduced. [1]. In practice, to some strongly advocate a cholecystectomy within 6 weeks of the initial biliary event. It should be taken into account that the conversion rate of LC after ERC is higher than with a standard LC [1,19]. This higher risk of conversion is still not understood. It is well known that bile is infected with bacteria after disruption of Oddi s sphincter by sphincterotomy and stone extraction during ERC. An important explanation for a higher conversion rate could be that ERC leads to an inflammation around the gall- bladder, including the hepatoduodenal ligament, making a laparoscopic procedure more demanding [2, 17]. According to the surgical paradigm the inflammatory response reaction will most likely be at its height 2 to 6 weeks after ERC. If this is the case it could be further hypothesized that the risk of a laparoscopic cholecystectomy in a patient with fibrosis of the hepatoduodenal ligament or with multiple adhesions of the gallbladder may outweigh the benefit of an early surgical intervention. As yet, we are unaware of literature that sheds any light on whether proper tuning of surgery after ERC is of influence on the risk of a laparoscopic cholecystectomy. In the current study we therefore evaluated whether timing is of any influence on the course of the laparoscopic procedure after ERC. 1 Methods All patients with suspicion of choledochocystolithiasis treated by LC following an ERC in the period from 1996 till 2001were analyzed. Demographic data, admission and discharge notes, blood results, radiology reports, ERC and operation details were collected and stored in a database. Common bile duct stones were strongly suspected if one or more of the following indications were present: jaundice and/or cholangitis, gallstone pancreatitis (acute abdominal pain and at least a fourfold increase of serum amylase activity), liver enzymes elevated to greater than twice normal levels (including bilirubine, alkaline phosphatase,
22 Chapter 1 c-glutamyl transferase, and transaminase), CBD diameter > 8 mm, and/ or stones detected by abdominal ultrasonography. ERC was done with a duodenoscope. Selective cannulation of the CBD was performed. If necessary, sphincterotomy and stone removal were carried out. If no bile duct stones at ERC were found, symptoms subsided, and blood results normalized, ductal clearance was assumed. If not, a second ERC followed. If no ductal clearance could be obtained, an open cholecystectomy with ductal exploration and stone extraction was performed, excluding these patients from this study. At the time of our study experience in -and techniques of- laparoscopic cholangiography and stone extraction was very limited. The timing of the LC was merely dictated by logistic reasons. If a surgeon decided that LC was indicated, the patient was put on a waiting list. Time interval between LC and ERC is as yet not taken into account when putting the patient on the waiting list. Patients are planned for surgery from the waiting list by a senior resident, often without knowledge of the case history, so time interval between ERC and LC is not known at the time of planning. In cases of acute cholecystitis, surgery was planned immediately or treatment was conservative followed by delayed surgery. This decision was dictated by time passed since the onset of patient symptoms and the surgeon s preference. Acute cholecystitis was diagnosed if right upper abdominal pain was associated with fever and elevated serum infection parameters with or without ultrasonographic evidence of acute inflammation. All surgeons performing the LC have extensive experience in this surgical procedure and have long passed their learning curve. If a senior surgical resident is performing an LC, conversion is not carried out without the supervising surgeon. To analyze the influence of time interval on the course of the LC, patients were subdivided into three groups: patients undergoing surgery within 2 weeks (group 1), 2 to 6 weeks (group 2), and >6 weeks after ERC (group 3). Primary outcome for the course of the LC procedure comprised the following four parameters: 1. Adhesions during LC, the gravity scored from 0 (none) to 3 (severe) 2. Damage to the bile duct 3. Operating time (start of incision until placement of last suture) 4. Conversion to an open procedure The secondary outcomes were per- and postoperative complications and hospital mortality. Statistical analysis was performed with SPSS for Windows. Comparison between groups was done using chi-square testing, with the Fisher exact test and the Kruskal-Wallis test when appropriate. P < 0.05 was considered statistically significant.
Conversion rate of laparoscopic cholecystectomy after endoscopic retrograde cholangiography 23 Results Choledochocystolithiasis was suspected in a total of 83 patients, 48 female and 35 male, with a median age of 53 years (range 17 85). In 52 patients the suspicion of common bile duct stones was based on elevated liver enzymes and/or abdominal ultrasonography. Three patients presented with a cholangitis and 14 patients had a biliary pancreatitis. In seven patients, records revealed only biliary colic pain, and in another seven patients the reason for suspicion remained unclear. During ERC 36 patients appeared to have no bile duct stones, 48 patients underwent a sphincterotomy, and 39 patients underwent stone removal. Ten patients were treated with a stent. Eleven patients (13%) developed a cholecystitis. In eight patients, acute cholecystitis was diagnosed at the time of ERC, and three patients developed an acute cholecystitis several weeks later while waiting for a surgical procedure. A total of two of 11 patients (18%) with an acute cholecystitis underwent surgery immediately; in the others surgery was postponed. Timing of the laparoscopic cholecystectomy after ERC is shown in Fig 1. More than half of the patients were operated more than 6 weeks after ERC. A minority of patients was operated in the assumed unfavourable 2 6 weeks after ERC. Table 1 shows the patients characteristics of the 83 patients, grouped according to the time interval between ERC and laparoscopic cholecystectomy. Interventions during 1 Fig. 1. Timing of laparoscopic cholecystectomy after endoscopic retrograde cholangiography. n=23 n=15 n=45 12 10 Number of patients 8 6 4 2 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 >26 Interval in weeks
24 Chapter 1 Table 1. Patients characteristics grouped according to the time interval Interval between ERC and LC Group 1 (<2 weeks) (n = 23) Group 2 (2 6 weeks) (n = 15) Group 3 (>6 weeks) (n = 45) p value Patients Median age (range) 52 (17 85) 48 (32 72) 58 (28 81) 0.24 a Male:female 11:12 7:8 17:28 0.68 b Interventions ERCP Sphincterotomy 10 (43.5%) 8 (53.3%) 30 (66.6%) 0.17 b Stone extraction 9 (39.1%) 8 (53.3%) 22 (48.9%) 0.64 b Stent 2 (8.7%) 5 (33.3%) 3 (6.6%) 0.03 b * Cholecystitis 1 (4.4%) 1 (6.7%) 9 (20%) 0.18 b a Kruskall-Wallis b Chi-square (Fisher s exact test) *Group 2 vs. group 3, p = 0.19; OR 6.99 (1.43 34.48) ERC, Endoscopic retrograde cholangiography; LC, laparoscopic cholecystectomy; ERCP, endoscopic retrograde cholangiopancreatography. ERC were closely similar in the three groups. The only difference was found in the use of stents during the ERC; in group 3 significantly more stents were used than in group 2. In the majority of patients, diagnosed as having had a cholecystitis (nine of 11 patients, 81%) or pancreatitis (13 of 19 patients, 68%) following ERC, laparoscopic cholecystectomy was done more than 6 weeks after ERC. The primary outcome for the course of the laparoscopic cholecystectomy in relation to the time interval is shown in Table 2. During the laparoscopic cholecystectomy, no or mild adhesions were encountered in about half of the patients regardless of the time interval between surgery and ERC. The common bile duct was twice superficially damaged; in both cases LC was performed >6 weeks after ERC (72 and 223 days). These tangential damages could be sutured laparoscopically. The operation time did not differ between the groups. The laparoscopic procedure had to be converted to open surgery in a total of 13 (16%) patients. Conversion rate was lowest in group 1: one of 23 patients (4%). Although group 3 comprised more patients with a history of cholecystitis and pancreatitis, conversion occurred in only seven of 45 patients (16%). Testing the difference of conversion rate between the three groups, the overall test (chi-square Fisher exact test) is marginally significant (p = 0.052). When we test the differences between the groups apart we find a significant higher conversion rate 2 6 weeks after ERC compared to LC 2 weeks [p = 0.027, odds ratio 11(1.13 106.8) (Fig. 2). The reason for conversion of the laparoscopic cholecystectomy to an open procedure is shown in Table 3. While adhesions and unclear anatomy were the main factors for
Conversion rate of laparoscopic cholecystectomy after endoscopic retrograde cholangiography 25 Table 2. Course of laparoscopic cholecystectomy in relation to time interval between ERC and LC Interval between ERC and LC Group 1 (<2 weeks) (n = 23) Group 2 (2 6 weeks) (n = 15) Group 3 (>6 weeks) (n = 45) p-value Gravity of adhesions None mild 10 (43%) 9 (60%) 20 (44%) 0.64 b Moderate severe 13 (57%) 6 (40%) 25 (56%) 0.03 b Lesion of the bile ducts Superficial lesion CBD 2 (4%) Operating time 0.35 a Median time 75 75 65 Range 40 150 40 200 30 135 0.052 b Conversion 1 (4%) 5 (33%) 7 (16%) 1 a Kruskall-Wallis b Chi-square (Fisher s exact test) ERC, Endoscopic retrograde cholangiography; LC, laparoscopic cholecystectomy; CBD, common bile duct conversion in group 2 and 3, a wide cystic duct was the only reason for conversion in group 1. Peroperative complications were seen in seven patients (8.3%) whereas 10 of all patients (11.9%) suffered from a postoperative complication. (Table 4) Twice a relaparotomy was needed; once because of an infected hematoma and once for intra-abdominal bleeding. Fig. 2. Percentage of conversion per interval group. P = 0.25 OR 4.1 (0.5-35.1) P = 0.03 OR 11 (1.13-106.8) P = 0.15 OR 0.37 (0.1-1.4) 30 Conversion (%) 20 10 0 group I group II group III Intervalgroup
26 Chapter 1 Table 3. Reason for conversion of laparoscopic cholecystectomy Interval between ERC and LC Group 1 Group 2 Group 3 (<2 weeks) (2 6 weeks) (>6 weeks) Reason for conversion (n = 1) (n = 5) (n = 7) Adhesions 2 4 Unclear anatomy 2 1 Wide cystic duct 1 Lesion CBD 1 Bleeding cystic artery 1 Unknown 1 ERC, Endoscopic retrograde cholangiography; LC, laparoscopic cholecystectomy; CBD, common bile duct Table 4. The per- and postoperative complications per time interval group Interval between ERC and LC Group 1 (<2 weeks) (n = 23) Group 2 (2 6 weeks) (n = 15) Group 3 (>6 weeks) (n = 45) p-value Peroperative complications Overall 1 (4.3%) 1 (6.7%) 5 (11.1%) 1.00 a Leakage of bile 1 Stone loss 1 1 Tangential lesion of CBD 2 Rupture of the gall bladder 1 Bleeding cystic artery 1 Postoperative complications Overall 4 (17.4%) 1 (6.7%) 5 (11.1%) 0.66 a Wound infection 2 2 Infected hematoma 1 1 Intraabdominal bleeding 1 Hematoma, abdominal wall 1 Bleeding needing transfusion 1 Subhepatic abscess 1 Reintervention Overall 2 (8.7%) 2 (4.4%) 0.64 a Laparotomy 2 Percutaneous drainage 2 ERC, Endoscopic retrograde cholangiography; LC, laparoscopic cholecystectomy; CBD, common bile duct a Chi-square (Fisher s exact test)
Conversion rate of laparoscopic cholecystectomy after endoscopic retrograde cholangiography 27 Percutaneous drainage was used to drain an infected hematoma in one patient and a sub hepatic abscess in another. Surprisingly, group 2 seems to have a more favourable outcome in incidence of per- and postoperative complication. Again statistical analysis, however, showed no significant difference between these small groups. No death occurred. 1 Discussion In the treatment of choledochocystolithiasis, a laparoscopic cholecystectomy after endoscopic retrograde cholangiography is justified to prevent recurrent biliary events. In the gallstone-induced acute pancreatitis cholecystectomy is advocated promptly, as the risk of recurrent pancreatitis is significantly reduced, and for this reason, surgery for choledochocystolithiasis is often advised within 6 weeks after ductal clearance. The results of our study, however, suggest that there is an increased risk of conversion of a laparoscopic cholecystectomy to an open procedure 2-6 weeks after ERC. The severity of adhesions encountered during the procedures and injury of bile ducts, as well as the time needed to perform the laparoscopic procedure, were not influenced by the time interval between LC and ERC. Although we found no difference in severity of adhesions between the groups, the high conversion rate due to adhesions 2 6 weeks after ERC suggests that these adhesions are less friendly and potentially dangerous compared to the adhesions encountered at surgery within two weeks of ERC. Of the 83 patients, 36 (43%) appeared to have no bile duct stones during the ERC. This relatively high percentage can be explained as, at the time of our study, ERC was still considered the main diagnostic tool for choledocholithiasis. Nowadays, the invasive ERC as a diagnostic tool is more often replaced by the noninvasive, highly specific MRI cholangiography. As MRI is implemented in the diagnostic algorithm of choledocholithiasis, the rate of negative ERC will be reduced, limiting ERC to therapeutic use [3,6,10,14]. It is well known from other authors [2,19] that ERC has an adverse effect on the conversion rate (8 55%) of the laparoscopic procedure. The conversion rate found in our study (16%) is relatively low compared to others. With a prospective randomized trial Boerma demonstrated a conversion rate of 55% in patients who were allocated to a wait-and-see policy after ERC and a 23% conversion rate in the elective LC group. They attributed the high conversion rate partly to the fact that LC is undertaken in a specific subgroup of patients, having complicated gallstone disease. The hypothesis that, after sphincterotomy, infected bile results in inflammation of the hepatoduodenal ligament and impedes the LC is an interesting thought. It could be expected that patients in whom a sphincterotomy is performed or removal of stones by manipulation is undertaken will sustain a stronger inflammatory reaction than patients
28 Chapter 1 who undergo an uneventful ERC. If so, this subset of patients could be more prone to a complicated course of the LC due to adhesions and/or unclear anatomy, consequently leading to a higher conversion rate. In our study, however, patients with a previous sphincterotomy (conversion rate 16%), stone extraction (conversion rate 16%), or stent placement (conversion rate 20%) during ERC did not have an adverse outcome of their laparoscopic procedure compared to patients with an uneventful ERC (conversion rate 13%). Comparable to findings in the study of Boerma et al., the conversion rate in our study was higher in patients with a history of cholecystitis. In three of 11 patients (27%) with cholecystitis the laparoscopic procedure had to be converted to an open cholecystectomy. Patients with elevated amylase levels after ERC did not have a higher conversion rate (5.3%). Ideally, this type of study should be performed as a prospective and randomized trial. We are well aware that the retrospective nonrandomized character of the study we performed is sensitive to various bias and confounding factors. A multifactorial study will contribute to a better analysis. Furthermore, the small number of patients studied could have induced a type 2 error, questioning the reliability of our outcome. However, to our knowledge, our study is the first to analyze whether time interval between ERC and LC is of any consequence in the course of the laparoscopic procedure. In cases of gallstone pancreatitis most surgeons now believe surgery should be performed during the initial hospitalization. The risk of recurrent pancreatitis is extremely slight if disease of the biliary tract can be eradicated safely by cholecystectomy and removal of all common bile duct stones on the first admission [1]. For cases of an acute cholecystitis randomized clinical trials have demonstrated that early surgery is safe and associated with a shorter hospitalization [12]. In cases of patients with combined gallstone disease Cuschieri et al. showed that laparoscopic cholecystectomy and bile duct exploration (single-stage procedure) was better than an endoscopic sphincterotomy and a subsequent laparoscopic cholecystectomy (two-stage procedure) because of a shorter admission time [8]. For now, the two-stage procedure is widely accepted, as few centres have the facilities and talents to implement a one-stage procedure. We believe that the course of a two-stage procedure can be improved further. As the experience in and techniques of laparoscopic procedures will develop, conversion rate will drop. A further reduction in conversion rate could be striven for by better understanding why the conversion rate after ERC is higher than for a standard LC. If risk factors for conversion of a laparoscopic procedure could be pointed out, the morbidity and mortality related to an open procedure could be prevented. According to our study, time interval after ERC is not yet clearly a factor to take into account, but further research is of interest considering the tendency to a higher conversion rate of a laparoscopic procedure 2 6 weeks after ERC.
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