Cholangitis score: a scoring system to predict severe cholangitis in gallstone pancreatitis

Abstract. Background/Purposes: Emergency biliary decompression and stone extraction are mandatory for patients with gallstone pancreatitis who have ampullary stone impaction or persistent stones and pus in the bile duct (severe cholangitis). The aim of this study was to devise a simple scoring system for the prediction of complicating severe cholangitis in gallstone pancreatitis. Methods: Clinical signs, laboratory data, and ultrasonography (US) findings at the time of admission, and the bile duct pathology at the time of bile duct exploration, were reviewed in 66 patients with gallstone pancreatitis. Variables which discriminated 26 patients with bile duct stones from 40 without were defined as predictive factors of bile duct stones. The receiver operating characteristic (ROC) curve was used to determine the optimal cutoff values of numerical variables. One point was allocated to each predictive factor, and the total score was defined as the cholangitis score (CS). Bile duct pathology identified at the time of bile duct exploration was graded into three categories: mild, moderate, and severe cholangitis. A threshold value of the CS, claimed to be predictive of severe cholangitis, was determined by using the ROC curve. Results: The scoring system consisted of four predictive factors: (1) pyrexia (temperature ≧38 °C), (2) elevated serum bilirubin (≧2.2 mg/dl), (3) dilated bile duct (≧11 mm maximum diameter on US), and (4) bile duct stones detected on US. The scoring system predicted severe cholangitis with 92% sensitivity and 98% specificity in patients with scores of three or four points. Conclusions: Patients with gallstone pancreatitis who meet three or four of the above predictive factors at the time of admission are likely to have severe cholangitis, and should be rapidly treated by biliary decompression and stone extraction. Received: July 13, 2001 / Accepted: November 16, 2001     

Acute cholangitis in association with acute pancreatitis: incidence, clinical features and outcome in relation to ERCP and endoscopic sphincterotomy

Although endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (ES) have been shown to be valuable in managing patients with acute cholangitis, their role in patients who have simultaneous acute cholangitis and acute pancreatitis is not known. We have reviewed 32 consecutive patients presenting with both conditions over ten years which represents 23.0 per cent of all cases of gallstone-related acute cholangitis and 14.4 per cent of all cases of biliary acute pancreatitis admitted during the same period. The majority of patients were elderly (median 76 years) and female (75 per cent). Five patients had previously undergone cholecystectomy. Eleven patients were clinically shocked (34 per cent) and blood cultures were positive in 9/14 cases (64 per cent). Twenty patients (63 per cent) had a predicted severe attack of acute pancreatitis (modified Glasgow criteria). Common bile duct (CBD) stones were identified in 15 of 23 patients with successful ERCP. Of these 23 patients, 9 were treated by endoscopic sphincterotomy (ES) alone, 5 by ES and surgery, 4 by surgery alone and 5 were treated conservatively. There was one death (4.3 per cent). Nine patients were managed without cholangiography; four had surgery and five were treated conservatively. There were three deaths (33 per cent; P = 0.10). Evidence of recent CBD stone passage was apparent in eight patients (25 per cent) compared with five out of eighty-seven patients (5.7 per cent) with acute cholangitis alone (P less than 0.005). The results indicate that ERCP and ES may have an important role in the management of these patients.     

Conservative management of cholestasis with and without fever in acute biliary pancreatitis

The presence of cholestasis in both mild and severe forms of acute biliary pancreatitis(ABP)does not justify,of itself,early endoscopic retrograde cholangiography(ERC)or endoscopic sphincterotomy(ES).Clinical support treatment of acute pancreatitis for one to two weeks is usually accompanied by regression of pancreatic edema,of cholestasis and by stone migration to the duodenum in 60%-88%of cases.On the other hand,in cases with both cholestasis and fever,a condition usually characterized as ABP associated with cholangitis,early ES is normally indicated.However,in daily clinical practice,it is practically impossible to guarantee the coexistence of cholangitis and mild or severe acute pancreatitis.Pain,fever and cholestasis,as well as mental confusion and hypotension,may be attributed to inflammatory and necrotic events related to ABP. Under these circumstances,evaluation of the bile duct by endo-ultrasonography(EUS)or magnetic resonance cholangiography(MRC)before performing ERC and ES seems reasonable.Thus,it is necessary to assess the effects of the association between early and opportune access to the treatment of local and systemic inflammatory/infectious effects of ABP with cholestasis and fever, and to characterize the possible scenarios and the subsequent approaches to the common bile duct,directed by less invasive examinations such as MRC or EUS.     

Spontaneous passage of bile duct stones: frequency of occurrence and relation to clinical presentation

BACKGROUND: Little is known about the spontaneous passage of bile duct stones. The aim of this study was to determine the rate of spontaneous stone passage and relate it to the clinical presentation of the bile duct stone. PATIENTS AND METHODS: Prospectively collected data were studied on a total of 1000 consecutive patients undergoing laparoscopic cholecystectomy with or without laparoscopic common duct exploration. Comparisons were made between 142 patients with common bile duct stones (CBDS), 468 patients who had no previous or current evidence of duct stones, and 390 patients who had good evidence of previous duct stones but none at the time of cholecystectomy. The evidence used for previous duct stones included a good history of jaundice or pancreatitis. In patients with biliary colic or cholecystitis, abnormal pre-operative liver function tests and/or a dilated common bile duct were taken as evidence of bile duct stones. RESULTS: Of the 1000 patients studied, 532 had evidence of stones in the common bile duct at some time prior to cholecystectomy. At the time of operation, only 142 patients had bile duct stones. By implication, 80%, 84%, 93% and 55% of patients presenting with pancreatitis, colic, cholecystitis and jaundice (73% overall) had passed their bile duct stones spontaneously. All 4 patients with cholangitis had duct stones at the time of operation. CONCLUSIONS: It is likely that most bile duct stones (3 in 4) pass spontaneously, especially after pancreatitis, biliary colic and cholecystitis but less commonly after jaundice. Cholangitis appears to be always associated with the presence of duct stones at the time of operation.     

慢性胰腺炎胰,胆管梗阻的处理：附6例报告

在３７例慢性胰腺炎病人中，８例合并胆道梗阻（２２％），４例合并主胰管梗阻（１１％）；６列同时或异时合并胰、胆管梗阻（１９％）。其中１例在发现胰管扩张１年后，出现胆管梗阻；２例同时发现胰、胆管梗阻。３例因黄疸在外院先行胆道手术，术后腹痛持续，影像检查证实尚伴有胰管梗阻，而再次行胰管减压手术。未合并胆石和（或）胆管炎的单纯胆道梗阻一般不引起严重的腹痛。对腹痛症状较重，而又无胆管结石的慢性胰腺炎病人应特别警惕是否同时合并胰管梗阻。     

Endoscopic sphincterotomy permits interval laparoscopic cholecystectomy in patients with moderately severe gallstone pancreatitis

Patients with moderately severe gallstone pancreatitis with substantial pancreatic and peripancreatic inflammation, but without organ failure, frequently have an open cholecystectomy to prevent recurrent pancreatitis. In these patients, prophylactic endoscopic retrograde cholangiography (ERC) with endoscopic sphincterotomy (ES) may prevent recurrent pancreatitis, permit laparoscopic cholecystectomy, and decrease risks. The medical records of all patients with pancreatitis undergoing cholecystectomy from 1999–2004 at the University of North Carolina Memorial Hospital were reviewed. Data regarding demographics, clinical course, etiology of pancreatitis, operative and endoscopic interventions, and outcome were extracted. Moderately severe gallstone-induced pancreatitis was defined as pancreatitis without organ failure but with extensive local inflammation. Thirty patients with moderately severe gallstone pancreatitis underwent ERC and ES and were discharged before cholecystectomy. Mean interval between ES and cholecystectomy was 102 ± 17 days. Cholecystectomy was performed laparoscopically in 27 (90%) patients, open in three (10%) patients, and converted to open in two (7%) patients, with a morbidity rate of 7% (two patients). No patient required drainage of a pseudocyst or developed recurrent pancreatitis. Interval complications resulted in hospital readmission in seven (23%) patients. In conclusion, recurrent biliary pancreatitis in patients with moderately severe gallstone pancreatitis is nil after ERC and ES. Hospital discharge of these patients permits interval laparoscopic cholecystectomy, but close follow-up is necessary in these potentially ill patients. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (poster presentation).     

Incidence and management of biliary pancreatitis in cholecystectomized patients: results of a 7-year study

Data are lacking concerning the frequency of biliary acute pancreatitis in the postcholecystectomy patient. The aim of this study was to identify patients at risk for biliary pancreatitis after cholecystectomy and to describe the therapeutic management of these patients, based on an analysis of 278 unselected patients with acute pancreatitis during a 7-year period. A biliary etiology was presumed in the presence of laboratory findings of cholestasis that could not be explained by another disease, together with the absence of any other known etiology of acute pancreatitis. A biliary cause of disease was found in 132 (47%) of 278 patients. Seventeen (13%) of 132 patients had a history of cholecystectomy. Endoscopic retrograde cholangiopancreatography was performed in all patients with a suspected biliary cause of acute pancreatitis. It showed bile duct stones, microlithiasis, or sludge in 14 patients, and was consistent with typical findings at the papilla of Vater after stone passage in another three patients. No surgical bile duct exploration was necessary. One patient with severe disease and infected pancreatic necrosis died of septic multiorgan failure. Presented, in part, at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Georgia, May 20–23, 2001 (poster presentation).     

Early endoscopic intervention versus early conservative management in patients with acute gallstone pancreatitis and biliopancreatic obstruction: a randomized clinical trial

OBJECTIVE: To test the hypothesis that early endoscopic intervention, performed on patients with acute gallstone pancreatitis and biliopancreatic obstruction, reduces systemic and local inflammation. SUMMARY BACKGROUND DATA: The role of early endoscopic intervention, in the treatment of acute gallstone pancreatitis, remains controversial. Previous randomized trials have not focused on the subgroup of patients with clinical evidence of biliopancreatic obstruction. METHODS: This single-center randomized clinical trial was performed between May 2000 and September 2005. Of 238 patients, admitted within 48 hours after the onset of acute gallstone pancreatitis, 103 with a distal bile duct measuring > or =8 mm combined with a total serum bilirubin > or =1.20 mg/dL, were randomized to receive either endoscopic retrograde cholangiopancreatography followed by endoscopic papillotomy for bile duct stones (EEI, n = 51) or early conservative management (ECM, n = 52). Patients with clinical evidence of coexisting acute cholangitis were excluded. Outcome measures included changes in organ failure score and computed tomography (CT) severity index during the first week after admission, incidence of local complications, and overall morbidity and mortality. RESULTS: The incidence of bile duct stones at EEI was 72% and 40% of patients in the ECM group had persisting bile duct stones at elective biliary surgery. No significant differences were found between the EEI and ECM groups regarding changes in mean organ failure score (P = 0.87), mean CT severity index (P = 0.88), incidence of local complications (6% vs. 6%, P = 0.99), overall morbidity (21% vs. 18%, P = 0.80), and mortality (6% vs. 2%, P = 1). CONCLUSIONS: The present study failed to provide evidence that early endoscopic intervention reduces systemic and local inflammation in patients with acute gallstone pancreatitis and biliopancreatic obstruction. If acute cholangitis can be safely excluded, early endoscopic intervention is not mandatory and should not be considered a standard indication.     

Effect of intraoperative cholangiography during cholecystectomy on outcome after gallstone pancreatitis

Acute gallstone pancreatitis has traditionally been managed by early cholecystectomy with intraoperative cholangiography (IOC). To evaluate the effect of IOC on patient outcome, we analyzed all patients operated on for acute gallstone pancreatitis at our institution over a 3-year period. A total of 200 patients (37 open, 163 laparoscopic) were evaluated. Nineteen of 34 patients who underwent preoperative endoscopic retrograde cholangiopancreatography (ERCP) were found to have common bile duct (CBD) stones. The 59 patients who underwent cholecystectomy with IOC had significantly longer operative times compared to the 141 patients who underwent cholecystectomy alone (167 vs. 105 minutes for open [P= 0.008] and 89 vs. 68 minutes for laparoscopic [P< 0.0001] operations). Of the 59 patients who underwent IOC, only nine (15%) had abnormal cholangiograms, and CBD exploration in seven revealed stones in four patients, edematous ampullae in two, and no abnormality in one. Six of eight patients (5 IOC, 3 no IOC) who required immediate postoperative ERCP were noted to have CBD stones. Patients who underwent IOC had significantly longer postoperative hospital stays (3.8 vs. 2.0 days [P= 0.007]). The incidence of retained CBD stones following surgery was similar (5.1% IOC, 2.8% no IOC). Although 7 of 122 patients who underwent laparoscopic cholecystectomy without IOC were readmitted, only one was found on ERCP to have a retained CBD stone. Age, sex, preoperative days, procedure type, and biliary-pancreatic complications after discharge did not differ significantly between patients with and without IOC. We conclude that IOC in patients operated on for acute gallstone pancreatitis results in a longer operative time and a prolonged postoperative course, but has no effect on the incidence of retained CBD stones. Presented at the Annual Meeting of the Southern California Chapter of the American College of Surgeons, Huntington Beach, California, January 21–23, 2000.     

胆源性胰腺炎手术时机的探讨

目的探讨胆源性胰腺炎（ＧＰ）的手术时机。方法采用统计学方法分析了５３例ＧＰ的临床资料。结果早期手术组（入院４８小时内）及延期手术组（入院４８小时后）并发症发生率分别为２９．２０％和３．５０％（Ｐ＜０．０５）;死亡率分别为８．３０％和０（Ｐ＜０．０５）。ＡＰＡＣＨＥ－Ⅱ记分≤８的轻型ＧＰ死亡率与手术时机无关,但早期手术组的并发症发生率（１１．１０％）及胆总管探查率（９１．７０％）明显高于延期手术组（Ｐ＜０．０５）。ＡＰＡＣＨＥ－Ⅱ记分＞８的重型ＧＰ并发症发生率及死亡率与手术时机有关,即早期手术组明显高于延期手术组。结论轻型ＧＰ应待急性发作缓解后延期手术;重型ＧＰ应采用延期与个体化相结合的处理原则。     

The theory of ''persisting'' common bile duct stones in severe gallstone pancreatitis.

There have been uncertainties as to the role of common bile duct (CBD) stones in severe gallstone pancreatitis. In order to resolve this, ERCP findings in 131 patients with acute pancreatitis were compared with predicted severity, clinical course and final outcome. Significant associations were found between 'persisting' CBD stones, coincidental acute cholangitis, predicted severity and actual outcome. There was evidence for acute obstruction of both the CBD and the pancreatic duct by CBD stones. The theory was therefore proposed that small migrating stones tend to initiate the attack, whereas larger 'persisting' stones tend to convert a mild attack into a severe attack. This hypothesis resolves previously irreconcilable theories and lends support to the use of urgent endoscopic sphincterotomy for treatment, but only in cases predicted to be severe.     

Outcomes of delayed endoscopic retrograde cholangiopancreatography in patients with acute biliary pancreatitis with cholangitis

ObjectiveThe recommended treatment for acute biliary pancreatitis(ABP) with cholangitis is urgent endoscopic retrograde cholangiopancreatography(ERCP). However, tight schedules in the endoscopy room mean that urgent ERCP may not always be performed. This study aimed to compare the outcomes of early (≤72 h) and delayed(>72 h) ERCP in patients with ABP with cholangitis.MethodsNinety-five patients diagnosed with ABP with cholangitis who underwent ERCP between May 2012 and April 2018 were retrospectively reviewed.ResultsSixty-seven patients(70.5%) were classified in the early ERCP and 28(29.5%) in the delayed ERCP groups. There was no significant difference in pancreatitis severity between the groups. Total bilirubin was higher in the early compared with the late ERCP group (5.7 ± 5.2 versus 3.5 ± 2.3 mg/dL, p = 0.03). Fewer patients in the early group had end-stage renal disease (0 versus 3, p = 0.006) and relatively fewer patients in the early group took aspirin (15(22.4%) versus 12(42.9%), p = 0.04). There were no significant differences between the early and delayed ERCP groups in terms of mortality (2(3.0%) versus 0), disease-related complications(11 (16.4%) versus 5(17.9%), p = 0.86), or ERCP-related complications(5(7.5%) versus 3(10.7%), p = 0.60). The total length of stay(LoS) was shorter in the early group(6.3 ± 4.4 versus 9.8 ± 6.1 days, p = 0.002). The rate of complete stone removal was lower in the early compared with the delayed ERCP group(32/42(76.2%) versus 18/18(100%), p = 0.02).ConclusionDelayed ERCP can be performed in selected patients with ABP with cholangitis, with similar complication rates but longer LoS compared with early ERCP.     

Choledocholithiasis in acute gallstone pancreatitis. Incidence and clinical significance

A prospective study of choledocholithiasis was performed using 110 patients with presumptive diagnoses of acute gallstone pancreatitis. The incidence of migrating and persistent bile duct stones was determined using stool screening and intraoperative cholangiography, and the clinical significance of continued stone obstruction of the papilla was investigated using ultrasound assessment of migration time and a second evaluation of prognostic signs. Pancreatic inflammation was confirmed at surgery in 51 patients, of whom only 27 had stones in the stools (n = 22) or the bile duct (n = 5), suggesting that choledocholithiasis may not be the sole triggering factor of acute gallstone pancreatitis. Neither delayed migration nor persistent stone obstruction of the papilla promoted pancreatic inflammation.     

腹腔镜手术治疗腹腔镜胆囊切除术后再发胆管结石合并胰腺炎的临床体会

目的:探讨腹腔镜胆囊切除术(laparoscopic cholecystectomy,LC)后再发胆管结石合并胰腺炎再次行腹腔镜治疗的可行性、手术时机及手术经验。方法:回顾分析2011年5月至2013年5月20例患者LC术后再发胆管结石合并急性胰腺炎行腹腔镜治疗的临床资料。结果:19例患者顺利完成胆总管探查取石引流术,1例中转开腹,中转率5%。5例患者入院时合并急性胆管炎症状(Charcot三联征)急诊手术,3例为重症胰腺炎予以保守治疗效果不佳,1~3 d内行胆管探查的同时行胰包膜切开灌洗引流术。余者均为轻型胰腺炎未合并急性胆管炎,予以对症治疗待腹痛症状缓解,酶学指标正常后行腹腔镜胆总管探查术。术后2例患者胆管仍有残余小结石,术后3个月经胆道镜取出。结论:LC术后再发胆管结石合并急性胰腺炎再次行腹腔镜胆管探查取石术安全、可行。胆管结石合并急性胰腺炎患者内环境紊乱,病情相对复杂,手术时机的把握、腔镜下胰包膜切开灌洗引流对重症胰腺炎的恢复至关重要。     

急性胆源性胰腺炎的治疗及手术时机的探讨

【摘要】 目的〓探讨急性胆源性胰腺炎的治疗方法及手术时机。方法 〓回顾肇庆市第一人民医院普外科2012年6月至2015年6月收治198例ABP患者的临床资料。结果〓198例中,8例经保守治疗病愈;138例轻症ABP患者在一次住院期间处理胆道结石;28例重症ABP患者经保守治疗病情好转,3~4周后处理胆道结石;22例重症梗阻型ABP经守保治疗无好转,急诊内镜或介入行胆道内引流,1~3月后再住院处理胆道结石;2例急性梗阻性胆管炎并重症胰腺炎患者行急诊开腹手术行胆道引流及胰腺周围引流,1例经治疗38 d病情好转出院,1例因严重的腹腔及肺部感染死亡。结论〓ABP的治疗应遵行保守治疗为主,延期手术的原则,根据有无胆道梗阻,胆管炎和胰腺炎的严重程度,决定外科治疗的方法及手术时机。     

经内镜乳头括约肌切开术治疗胆总管结石临床研究

目的探讨经内镜乳头括约肌切开术(EST)治疗胆总管结石的临床效果。方法对256例胆总管结石(9~15mm)患者采用经内镜乳头括约肌切开术(EST)治疗。结果EST取石成功249例,成功率97.3%,其中221例一次取净结石,28例2~3次取净结石,7例取石未成功。EST术后发生并发症16例,总发生率6.3%,其中急性胰腺炎10例,急性胆管炎5例。结论经内镜乳头括约肌切开术治疗胆总管结石是一项安全可靠的新技术。     

Gallstone cholangitis: a 10-year experience of combined endoscopic and laparoscopic treatment

BACKGROUND: To date, no procedure has yet been identified as the gold standard for the treatment of gallstone cholangitis in the laparoscopic era. METHODS: The data of 109 consecutive patients with acute cholangitis were prospectively entered into a computerized database. All patients were managed according to a standard protocol. The main treatments were endoscopic retrograde cholangiography (ERC) combined with endoscopic sphincterotomy (ES), followed by interval laparoscopic cholecystectomy (LC). Patients in whom ERC or endoscopic stone clearance failed were managed by emergency open common bile duct exploration. LC was performed with a standardized four-cannula technique. The mean duration of surgery, conversion rate, and postoperative outcome of these patients were evaluated. RESULTS: ERC was successful in 103 patients (94.5%). In five of these patients (4.8%), no bile duct stones were found. The 98 patients (95.2%) with common bile duct stones were referred for ES. The bile duct stones were successfully removed after ES in 93 cases (94.9%). The overall failure rate of ERC and ES for choledocholithiasis was 10.1%. Self-limiting pancreatitis occurred in four patients (4.3%). Overall, two of the 109 patients died (1.8%). After ES, 81 patients underwent LC. LC was performed successfully in 74 patients (91.3%). Conversion to open surgery was required in seven patients (8.7%). The morbidity rate after cholecystectomy was 7.4%; the morbidity rate after open bile duct exploration was 36.4% (p<0.05). Fifteen patients were managed conservatively after initial endoscopic management of their cholangitis. The overall incidence of recurrent biliary symptoms was significantly higher among patients with gallbladder in place than for patients who underwent cholecystectomy (38.5% vs 1.5%, p<0.001). CONCLUSIONS: ES followed by LC is a safe and effective approach for the management of gallstone cholangitis; cholecystectomy should be performed in patients with gallstone cholangitis unless the operative risk is extremely high. These high operative risk patients and those who refuse surgery after ES should be warned that they are at high risk for recurrent biliary symptoms.     

腹腔镜术中联合十二指肠镜治疗细径胆总管结石121例报告

目的探讨腹腔镜胆囊切除术中联合十二指肠镜下乳头切开取石术治疗胆囊结石继发细径胆总管结石的手术方法和适应证。方法完成腹腔镜胆囊切除后,经胆囊管残端插入输尿管导管至十二指肠腔,经口插入十二指肠镜至十二指肠乳头,针式刀在输尿管导管指引下对乳头施行切开术,用十二指肠镜取石网或球囊取石。结果治疗121例,107例乳头切开取石成功,9例乳头切开排石成功,3例中转为其他术式,2例胆管残留结石。术后轻症胰腺炎8例。无肠穿孔、胆管穿孔、胆漏、大出血、重症胰腺炎等并发症,无死亡。结论只要选择合适的病例,腹腔镜胆囊切除术中联合十二指肠镜下乳头切开取石术治疗胆囊结石继发细径胆总管结石是可行、有效和安全的。     

Total bilirubin is a useful predictor of persisting common bile duct stone in gallstone pancreatitis

Accepted guidelines for preoperative endoscopic retrograde cholangiopancreatography (ERCP) in gallstone pancreatitis are lacking. Our previous investigations suggested that serum total bilirubin on hospital Day 2 best predicts persisting common bile duct (CBD) stones. We aim to identify an optimal total bilirubin threshold on hospital Day 2 that would predict persisting CBD stones and guide obtaining preoperative ERCP. Prospective and retrospective data were available from 200 consecutive patients with gallstone pancreatitis at a public teaching hospital from 2003 through 2007. Charts were examined for persisting CBD stones on ERCP and/or intraoperative cholangiography during laparoscopic cholecystectomy. Patients with cholangitis (n = 18) were excluded. Nineteen of the remaining 182 (10%) patients had CBD stones. Mean hospital Day 2 bilirubin was 3.7 mg/dL for patients with CBD stones versus 1.4 mg/dL for those without (P < 0.0001). Seventeen patients (9%) had total bilirubin 4 or greater on hospital Day 2. Of these, eight (4%) had CBD stones (specificity 94%). Of the 165 patients with total bilirubin less than 4, 11 (7%) had CBD stones (P < 0.0001). In gallstone pancreatitis, a serum total bilirubin level 4 mg/dL or greater on hospital Day 2 predicts persisting CBD stones with enough specificity to serve as a practical guideline for ERCP while minimizing unnecessary procedures.