795

Aust. N . Z . J . Surg. 1992,62,795-801

OPEN CHOLECYSTECTOMY: A CONTROL GROUP FOR COMPARISON WITH LAPAROSCOPIC CHOLECYSTECTOMY M. R. Cox, I. F. GUNN,M. C. EASTMAN, R. F. HUNTAND A. W. HEINZ Department of Surgery, Goulburn Valley Base Hospital, Shepparton, Victoria, Australia Laparoscopic cholecystectomy is rapidly becoming accepted as the best method for the treatment of symptomatic cholelithiasis. Randomized clinical trials comparing laparoscopic cholecystectomy with open cholecystectomy are unlikely to be performed. In order to compare these two operations, surgeons need an historical control group of patients who have undergone a conventional open cholecystectomy. The aim of this study was to document a control group of patients having an open cholecystectomy and compare them with patients having a laparoscopic cholecystectomy. This was achieved by a retrospective study of all patients who had an open cholecystectomy from January 1985 to December 1989. Four hundred and fifty-seven patients, 345 women and 112 men, had a cholecystectomy. Exploration of the common bile duct (ECBD) was performed in 59 (12.5%) cases. The mean operative duration was 73 min for cholecystectomy and 118 min for cholecystectomy and ECBD. The shortest mean postoperative stay was for an elective cholecystectomy (5.3 days) and the longest mean postoperative stay was for urgent admissions requiring ECBD (12.0 days). Operative dissection was difficult in 14.1% of elective cases and 51.8% of urgent cases. Ninety-seven (19.5%) patients had an additional procedure, unrelated to cholelithiasis, at the same operation; 44 did not require laparotomy, 31 had interval appendicectomies, and 22 other cases required laparotomy in order to perform the additional procedure. All but one patient required postoperative narcotic analgesia. The mean duration of narcotic analgesia was 2.3 days. The complication rate was 35.2% for cholecystectomy and 62.5% for ECBD. If pulmonary atelectasis is excluded as a complication, these complication rates fell to 6.8% and 20.1 % , respectively. There was one right hepatic duct injury and no postoperative deaths. Comparison of these results with the published results for laparoscopic cholecystectomy revealed that although open cholecystectomy takes less time to perform, it is associated with a longer postoperative stay, greater narcotic analgesic requirements and more respiratory complications.

Key words: acute cholecystitis, cholecystectomy, cholelithiasis, common bile duct exploration.

Introduction The introduction of laparoscopic cholecystectomy has created unprecedented interest and excitement in the world of general surgery. 1 ~ No 3 other topic in general surgery has received as much editorial attention in medical journals during 1990 and 1991. The preliminary results are excellent with reduced bed occupancy, minimal morbidity and a more rapid return of patients to normal a ~ t i v i t i e s . ~The - ' ~ ideal method to compare laparoscopic cholecystectomy with open cholecystectomy would be a randomized, controlled clinical trial. Such a trial is unlikely to be performed due to ethical constraints and poor patient recruitment for fear of being randomized into the open cholecystectomy arm.'3 Any comparison of laparoscopic cholecystectomy against open cholecysCorrespondence: Dr Michael Cox, Department of Surgery, Flinders Medical Centre, Bedford Park, SA 5042, Australia. Accepted for publication 6 May 1992

tectomy will need to use either non-randomized groups of patients or retrospective data from an historical control group of open cholecystectomy patients. l 3 The aim of this study was to document a control group of patients, who had undergone open cholecystectomy, to be used for comparison with patients having a laparoscopic cholecystectomy. The emphasis was on; the indications for surgery, operative duration, length of postoperative stay, frequency of difficult dissection and morbidity and mortality.

Methods The medical records of all patients having an open cholecystectomy from January 1985 to December 1989 at the Goulburn Valley Base Hospital, Shepparton, Victoria, were carefully examined. The data for each patient were stored and subsequently analysed using a personal computer (Amiga 500, Commodore, Japan) and a data processing package (Superbase Professional, Precision Software, Worcester Park, England).

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Admissions were divided into elective and urgent with an urgent admission defined as an admission at the time of the initial presentation to the emergency department. Acute biliary pain was defined as a history typical of biliary pain which had not resolved after 4 h but without associated fever or leucocytosis. Acute cholecystitis was defined as biliary pain in association with fever and leucocytosis. The duration of operation was derived from the anaesthetic record and was taken as the time from induction of anaesthesia until the time of administration of the reversal agents. The operation notes were studied and the presence of adhesions, inflammation and those dissections that were described as difficult were recorded. Additional operative procedures and their indications were recorded. The postoperative narcotic requirements were obtained from the narcotic infusion sheet and the treatment sheet. Each admission was assessed for postoperative complications. Pulmonary atelectasis was defined as a temperature of over 38°C with clinical signs of atelectasis recorded in the notes or a chest X-ray showing basal atelectasis. Pneumonia was defined as a fever with positive clinical signs recorded in the notes, a confirmatory chest X-ray and/or positive sputum cultures. A wound infection was defined as a discharge of pus from the wound. Deep venous thrombosis was only noted if proven by venography. Pulmonary embolism was said to have occurred where there was strong clinical, biochemical and radiological evidence of pulmonary embolism, as nuclear ventilation and perfusion scans were not available. Numerical data were compared using an unpaired Student’s t-test. l4 Statistical significance was accepted if P < 0.05. Results During the 5 year study period 457 patients had an open cholecystectomy. The mean age was 52.5 years with a range of 12-87 years. There were 345 women and 112 men (ratio 3 : 1). There were 290 (63.6%) elective admissions and 167 (36.4%) urgent admissions. The majority of the elective admissions (94.8%) were for recurrent biliary pain, 14 of these patients were also jaundiced at the time of, or just before, admission. Of the remaining 15 patients, 10 presented with a recent history of obstructive jaundice, four had a previous episode of acute gallstone pancreatitis and one patient had asymptomatic cholelithiasis. Eighty-six (51.5%) of the acute admissions had acute cholecystitis, while 54 (32.3%) had acute biliary pain. Eighteen patients (10.8%) were admitted urgently with obstructive jaundice, three of these had ascending cholangitis. Twenty-two ( 1 3.2%) patients had acute gallstone pancreatitis. Three of the four remaining patients were admitted with an initial diagnosis of ischaemic heart disease

but were later diagnosed as having acute cholecystitis. The fourth patient was admitted with a small bowel obstruction due to adhesions, this resolved with conservative management, but the patient developed acute cholecystitis during the same admission. Fifty-nine patients (12.9%) had an exploration of the common bile duct (ECBD); 34 were elective and 25 were urgent admissions. Fifty-seven of the 59 patients had an abnormal operative cholangiogram, the remaining two were jaundiced with an easily palpable common bile duct (CBD) stone. Three CBD explorations were negative. Three different cohorts of patients were compared in order to study the duration of the operation and the duration of the postoperative inpatient stay. These were: (i) all patients not having an ECBD versus all patients having an ECBD; (ii) elective versus acute admissions where there was no ECBD performed; and (iii) elective versus acute admissions where an ECBD was performed (Table 1). As expected the mean operative time was significantly longer when the common bile duct needed to be explored. There was no significant difference in the mean operative duration between acute and elective operations. As expected the mean postoperative stay was longer in those patients having an ECBD and for patients that were admitted urgently. The operative dissection was difficult in 41 (14.1%) elective cases with the most common reason being dense fibrosis in Calot’s triangle (Table 2). There were at least five cases where a laparoscopic approach would have definitely required conversion to an open operation. Eighty-seven (52.4%) patients having a cholecystectomy following an urgent admission had a difficult dissection (Table 2). Most of these patients presented with either acute cholecystitis or acute biliary pain. The most common problem was severe oedema or frank necrosis of an acutely inflamed gall-bladder or dense fibrosis in Calot’s triangle. There were five cases that would have definitely required conversion to an open operation if the laparoscopic approach had been attempted initially. No doubt other elective or urgent cases may have required conversion to an open operation if laparoscopic cholecystectomy had been attempted initially, but the number cannot be assessed by this retrospective study. Ninety-seven patients (19.5%) had another procedure performed during the same anaesthetic. Fortyfour patients did not require a laparotomy for the additional procedure (e.g. inguinal hernia repair). There were 31 interval appendicectomies performed for histologically normal appendices. Apart from an interval appendicectomy, 22 patients required a laparotomy in order to perform the additional operation. Fifteen of the 22 had an elective operation and in 12 the additional procedure was planned in addition to the cholecystectomy. Oniy three patients having

OPEN CHOLECYSTECTOMY

797

Table 1. The mean (i f s.e.m.) operative duration and postoperative inpatient stay for the three patient classifications

Category All cases No ECBD

No.

Mean operation time (min)

Postoperative stay (days)

7 3 + 12 118 f 15 ( t = 9.7, P 0.1). Four patients had no narcotic analgesia, one did not seem to require narcotic analgesia and the other three had postoperative epidural analgesia. The incidence of complications was higher in patients having an ECBD compared with those not needing an ECBD (62.5 and 35.2%, respectively; Table 4). The incidence of complications was similar between urgent and elective admissions (39.9 and 36.5%, respectively). The most frequent complication was pulmonary atelectasis. Excluding pulmonary atelectasis, the incidence of complications was 6.8% in those having a cholecystectomy and 20.1YO in patients having a cholecystectomy and ECBD. There was one case of partial transection of the right hepatic duct that was recognized at operation and repaired over a T-tube with no subsequent short- or long-term complications. All three cases of retained CBD stones were successfully treated by endoscopic retrograde cholangiography (ERCP) and endoscopic sphincterotomy (ES). There were no postoperative deaths in this series.

COX E T A L .

798

Table 3. Incidence and mean duration of narcotic anal-

gesia after cholecystectomy Mode of administration

All cases No. Days

No ECBD No. Days

Infusionalone Injectionalone Infusion and injection Total

153 2.0 137 2.2

140 2.0

13

118 2.2

19

2.6 2.3

163 2.9

136 2.9

27

2.7

453 2.3

394 2.3

59

2.7

ECBD No. Days

Table 4. Postoperative complications No

Complication Atelectasis

Pneumonia Wound infection Bile leak Acute pancreatitis Hepatic duct injury Retained CBD stone Dislodged T-tube (D3) Deep venous thrombosis Pulmonary embolism Myocardial infarction Urinary infection Urinary retention Reactionary haemorrhage Acute tubular necrosis Cerebrovascular accident

No. cases

ECBD

ECBD

130 12 20

105 10 14 I1

25 2

1

-

1

-

3

-

I 1 5 I

-

3 I

20

18

I

1

-

2 I

2 1

-

1

1

15 1 1

1 4 I

6 4

-

1 -

2

-

Discussion This study documents a control population of patients having an open cholecystectomy and compares them with patients having a laparoscopic cholecystectomy. The study was performed during the 5 year period before the introduction of laparoscopic cholecystectomy in Victoria."." This is a population based study from a large provincial hospital that serves a population of 100000-120000. The female to male ratio of 3 : 1 was similar to other studies on and l a p a r o ~ c o p i c ~chol-~ ecystectomy. The mean age (52.5 years) was similar to other series on open cholecy~tectomy'~-'~ but slightly higher than the mean age of 43.2-50 years reported for laparoscopic cholecystectomy.2,4-9 This apparent difference may reflect a selection bias toward younger patients in the laparoscopic cholecystectomy studies or a local referral bias of older patients being treated at the public hospital. As expected the majority of admissions (63.6%) were elective for recurrent biliary pain. One hundred and forty of the urgent admissions were for either acute cholecystitis or unresolved biliary pain, representing

30.6% of all admissions. The reported incidence of acute cholecystitis as an indication for open cholecystectomy varies between 14.6 and 35% .18,20-22 The high incidence of acute cholecystitis in the present study may be falsely elevated by the local referral bias of acute cases to the public hospital. Laparoscopic cholecystectomy was initially said to be contraindicated in patients with acute cholecystiti^.^.^,*' Therefore, many of the reports have a low (0-6%) incidence of acute cholecystitis treated by laparoscopic cholecystectomy ,1,7-9,23 because surgeons avoided performing laparoscopic cholecystectomy in patients with acute cholecystitis. Many experienced surgeons now attempt laparoscopic cholecystectomy in patients with acute cholecystitis,7,9,12,?4 The incidence of acute cholecystitistreated by laparoscopic cholecystectomy will rise over a period of time. The incidence of choledocholithiasis requiring ECBD was similar to other reports where ECBD was performed after an abnormal operative cholang i o g r a ~ n . ~ ' The , ~ ~ introduction -~~ of laparoscopic cholecystectomy will alter the management of choledocholithiasis at the time of cholecystectomy. There are several strategies of management including: selective pre-operative ERCP and ES;9,'",23328329 postoperative ERCP and ES;7,24,3033'laparoscopic ECBD;6324open ECBD at the initial operation;29332 or expectant spontaneous passage for small calc u L 6 Most series of laparoscopic cholecystectomy have a lower incidence (0-7.8'70) of choledocholithiasi~,'*~.'-''which represents a selection bias against patients with possible CBD calculi. Clinical trials are required to determine the best method for the management of choledocholithiasis at the time of laparoscopic cholecystectomy . The mean operative duration, including the preand postoperative anaesthetic times for open cholecystectomy was 73 min. This time is a more useful measure of the overall use of operating theatre time. The reported mean operative time for laparoscopic cholecystectomy varies from 70 to 138 ,in,4-7,If,23,33 These reports do not define how the operative time was measured, but one assumes they are 'skin to skin' times, which does not include the pre- and postoperative anaesthetic times. One report where the anaesthetic time was included had a mean operative duration of 1291nin.~The shorter reported mean operating time of 70 min was in a series where operative cholangiography was not p e r f ~ r m e d ,which ~ significantly reduces the operative time by a mean of 20 n ~ i n . ' . ~In the present series the mean operative time for cholecystectomy and ECBD (1 18 min) was similar to that reported in another As yet there are no reported series of combined laparoscopic and endoscopic management of choledocholithiasis, but no doubt the total operating time shall be longer than that for open ECBD.

199

OPEN CHOLECYSTECTOMY

patients with symptomatic cholelithiasis shall deterThe apparent disadvantage of a longer operating mine the conversion rate for laparoscopic cholecystime is far outweighed by the markedly reduced tectomy for elective and acute cases. There will still inpatient stay. In this study the mean postoperative be a role for open cholecystectomy in the managestay for a patient having an elective cholecystectomy ment of cholelithiasis, particularly for acute was 5.3 days. This contrasts with a reported postoperative stay of 6-12.5 days in other s t ~ d i e s , ~ ~ ’ cholecystitis. ~~~,~~ An incidence of 19.5% of cases having an addiand an oft perceived duration of only 2-3 days.35 tional operative procedure compares with an inciElective laparoscopic cholecystectomy has a much dence of 21-32% in other series.’7337Jolly et al. shorter mean postoperative stay of 1.2-2.2 days.4-” fail to describe the types of additional procedures37 Patients having a laparoscopic cholecystectomy for and Gilliland and Traverso exclude any major intraacute cholecystitis have a mean postoperative stay abdominal operations from their analysis but perof 2.7 days”,36 which is much shorter than for an open cholecystectomy. Patients with choledochoformed 55 liver biopsies as an additional procedure. I7 Excluding interval appendicectomy, only 22 (4.8%) lithiasis having an ERCP before or after a laparoscopic cholecystectomy would also be expected to cases in the present series required a laparotomy have a postoperative stay shorter than 9.2 days. to perform the additional procedure. Hence, few Another major advantage of laparoscopic cholecyspatients should be excluded from laparoscopic choltectomy is the rapid return to normal activities; a ecystectomy on the basis of requiring an additional mean of 5-12 day^.^-',",^^ There were no data availoperative procedure. Parenteral narcotic analgesia was required in all able from the present study on the time it took for patients to return to normal activities, but other but one patient for a mean duration of 2.3 days after studies report a mean time of between 4 and 6 open cholecystectomy . Only 32-39% of patients weeks. ‘’,22 require parenteral narcotics after laparoscopic cholFive of the elective cases would have had to be ecystectomy, 63-7 1YO require oral narcotics and converted to an open operation, because of opera21-36% need no narcotic This reductive findings, if a laparoscopic cholecystectomy tion in narcotic analgesia requirements after lapawas attempted. At open operation there were anothroscopic cholecystectomy is due to the absence of er 36 cases that had a difficult dissection. If all of the laparotomy wound. The use of intercostal nerve these required conversion from a laparoscopic to an blockade after open cholecystectomy did not reduce open operation, the overall need for an open operathe duration of narcotic analgesia.38 tion would have been 15.3%. Some of the difficult The incidence of complications after open choldissections may have been possible laparoscopically, ecystectomy in this study was found to be much but this could not be assessed from the retrospective higher than the reported incidence of 2- 13% data. The reported incidence of conversion to open for cholecystectomy and 15.9-25.5% for operation for elective laparoscopic cholecystectomy ECBD.’5.17,2’,223 26,34,37The most frequent compliis between 3.6 and 13%. cation in this series was pulmonary atelectasis. Most Those reports with a lower incidence of conversion may studies on open cholecystectomy do not report the have selected patients with a more favourable patholincidence of pulmonary atelectasis. Two studies ogy, or the surgeon may have been more expert or that did report atelectasis had an incidence of persistent with laparoscopic cholecystectomy. As 0.3-2.3% ,I7,’’ but no definition of atelectasis was expected a larger proportion of open cholecystecgiven and their results almost certainly underestomies following an urgent admission were techtimated the true incidence of atelectasis. Failure to nically difficult. This was usually due to severe report atelectasis as a postoperative complication inflammation or dense fibrosis in Calot’s triangle. may be due to the belief that, because it is so comFive cases would have required conversion to an mon and does not increase the postoperative stay, it open operation, doubtless other cases may have reis not a postoperative complication. Certainly it did quired conversion but again, the study did not allow not significantly increase the mean postoperative this to be assessed. Early reports on laparoscopic stay in this study (unreported data), but its high cholecystectomy listed acute cholecystitis as a relaincidence reveals the potential for the development tive contraindication to laparoscopic cholecystecof postoperative pneumonia and/or respiratory failt~my.~ Many - ~ authors with improved techniques ure and reflects the reduction in pulmonary function and greater experience now attempt laparoscopic after open cholecystectomy.” The reported incicholecystectomy in patients presenting with acute dence of respiratory complications after laparosc h o ~ e c y s t i t i s . ~o ~ne ~ ~ ’study ~ ~ ~ ~on~ ~laparoscopic copic cholecystectomy is zer0.4-6.’31’,33 These reports cholecystectomy for acute cholecystitis had a conmay or may not be including pulmonary atelectasis version rate of 6 % for oedematous cholecystitis and as a respiratory complication. Future reports on 30% for severe, necrotizing cholecystitis.l 2 Future laparoscopic cholecystectomy should include the incistudies by experienced laparoscopic surgeons, with dence of pulmonary atelectasis as a complication. a policy of laparoscopic cholecystectomy for all Although laparoscopic cholecystectomy requires a 1.234-’0,23328332

800

COX E T A L .

longer anaesthetic, which would increase the incidence of a t e l e c t a ~ i s ,the ~ - ~absence ~ of an abdominal wound and the associated pain leads to significantly better postoperative pulmonary function and reduced pulmonary complication^.^^ Excluding pulmonary atelectasis as a complication, the complication rate was 6.8% for cholecystectomy and 20.1% for ECBD, which is comparable with previously reported complication rates. 15,21322,26,34,37The complication rate for laparoscopic cholecystectomy is 1.611.2% ,4-9212,33 with most of these being minor and not life-threatening. Common bile duct injury is a serious complication of biliary surgery. There was one duct injury in this serious which compares favourably with other open cholecystectomy series where the incidence of CBD damage is between 0.1 and 0.25%. '6,42 The incidence of CBD damage at laparoscopic cholecystectomy is between 0 and 1.2yo,6-10,28,33 This may not reflect the true incidence of CBD injuries following laparoscopic cholecystectomy because many of these reports come from leading centres and other centres are unlikely to publish results showing a high incidence of CBD injury. As CBD injury may not be manifested for several years, a prospective, long-term, multicentre follow-up study is required to determine the true incidence of CBD injury in laparoscopic cholecystectomy and whether the frequency of this particular complication compares favourably with the results for open cholecystectomy. The higher incidence of complications associated with ECBD is consistent with other reports. The complication rate for combined laparoscopic and endoscopic management of choledocholithiasis is unknown. The complication rate for ERCP and ES is 2.9-19.8% with a mortality of 0- 1 1.3% .43-45 However, in the past many patients having ERCP and ES were elderly with multiple medical problems and were considered unfit for surgery, while young fit patients were managed surgically. This produced a selection bias against ERCP and ES.44-46Two recent studies where selective pre-operative ERCP and ES were performed before open cholecystectomy for patients with suspected choledocholithiasis had a low morbidity (02.9%) and zero mortality.46247Assuming that the combined complication rate of both laparoscopic cholecystectomy and ERCP and ES are additive, then the complication rate for the endoscopic and/or laparoscopic management of CBD and gall-bladder calculi would be at least comparable with open ECBD. Prospective studies on the combined endoscopic and laparoscopic management of choledocholithiasis are required to assess the best approach in the management of a patient with possible choledocholithiasis. There were no deaths in this series. Other studies on open cholecystectomy have mortality rates ranging from 0 to 130/~16,17,21.25~27,37 with a greater 19321,22,34

mortality in the elderly'' and in patients having an ECBD. 1'325,34 The reported mortality for laparoscopic cholecystectomy is very low at 0-0.3% .1,4-11,28,31 The conclusion from studying the control group of patients undergoing an open cholecystectomy is that although this operation can be performed more quickly than laparoscopic cholecystectomy it is associated with a longer postoperative hospital stay, increased narcotic requirement and a higher frequency of pulmonary complication. Further studies are required to assess the role of routine laparoscopic cholecystectomy in patients with acute cholecystitis and the best method of management for patients that may have choledocholithiasis.

Acknowledgements The authors thank Mrs Judith A . Sumner and Miss Jacqueline J. Foster and their staff for assistance with the retrieval of the medical records for this study.

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