Nov 16, 1995 - dure were collected prospectively and stored in a com- puterized database (FileMaker Pro, version 2.0, Claris. Corporation, Santa Clara, CA).
ANNALS OF SURGERY Vol. 224, No. 2, 198-203 © 1996 Lippincott-Raven Publishers
A Learning Curve for Laparoscopic Fundoplication Definable, Avoidable, or a Waste of Time? David I. Watson, M.B.B.S., F.R.A.C.S., Robert J. Baigrie, M.D., F.R.C.S., and Glyn G. Jamieson, M.S., F.A.C.S., F.R.A.C.S.
From The Royal Adelaide Centre for Endoscopic Surgery and University Department of Surgery, Royal Adelaide Hospital, Adelaide, Australia
Objective The objective of this study was to determine whether a learning curve for laparoscopic fundoplication can be defined, and whether steps can be taken to avoid any difficulties associated with it.
Summary Background Data Although early outcomes after laparoscopic fundoplication have been promising, complications unique to the procedure have been described. Learning curve problems may contribute to these difficulties. Although training recommendations have been published by some professional bodies, there is disagreement about what constitutes adequate supervised experience before the solo performance of laparoscopic antireflux surgery, and the true length of the learning curve.
Methods The outcome of 280 laparoscopic fundoplications undertaken by 11 surgeons during a 46-month period was assessed prospectively. The experience was analyzed in three different ways: 1) by an assessment of the overall learning experience within chronologically arranged groups, 2) by an assessment of all individual experiences grouped according to the experience of individual surgeons, and 3) by a comparison of early outcomes of operations performed by the surgeons who initiated laparoscopic fundoplication with the early experience of surgeons beginning laparoscopic fundoplication later in the overall institutional experience.
Results The complication, reoperation, and laparoscopic to open conversion rates all were higher in the first 50 cases performed by the overall group, and in the first 20 cases performed by each individual surgeon. These rates were even higher in the initial first 20 cases, and the first 5 individual cases. However, adverse outcomes were less likely when surgeons began fundoplication later in the overall experience, when experienced supervision could be provided.
Conclusions A learning curve for laparoscopic fundoplication can be defined. Experienced supervision should be sought by surgeons beginning laparoscopic fundoplication during their first 20 procedures. This should minimize adverse outcomes associated with an individual's learning curve.
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Since the first report of laparoscopic Nissen fundoplication in 1991,1 this procedure has been rapidly adopted by surgeons interested in the management of gastroesophageal reflux disease. Although early outcomes have been promising, there also has been a downside to the laparoscopic approach. There appear to be complications that are unique to the laparoscopic procedure: esophageal perforation,2'3 acute para-esophageal herniation4'5 stenosis of the esophageal hiatus,6 and pneumothorax.7 Our own reported initial experience8 was associated with a higher reoperation rate than might have been expected after open surgery. This experience comprised procedures performed by a greater number of surgeons and surgeons-in-training than that reported from most centers. Learning difficulties may be less apparent in reports from individuals or small groups of surgeons. Training recommendations for laparoscopic procedures have been published by professional bodies such as the European Association of Endoscopic Surgeons.9 Although providing some help to hospital credentialing committees, such guidelines are not specific, presumably because of disagreement about what constitutes adequate supervised experience before the solo performance of complex laparoscopic procedures, and the true length of the learning curve. This study assesses a large experience with laparoscopic fundoplication to determine whether a learning curve can be defined, whether it is clinically significant, and whether any of the adverse outcomes associated with it can be avoided by the careful supervision of new surgeons.
METHODS From September 1991 to July 1995, 11 surgeons or surgeons-in-training undertook 280 laparoscopic fundoplications at the Royal Adelaide Hospital. Follow-up has ranged up to 46 months (median 18). Each surgeon's individual experience began at a different stage in the overall institutional experience. Details of each procedure were collected prospectively and stored in a computerized database (FileMaker Pro, version 2.0, Claris Corporation, Santa Clara, CA). These data have been analyzed in three ways to determine the learning curve for laparoscopic fundoplication. Information was collected for each of the following: patient weight, complications, requirement for surgical revision, operating time, performance of hiatal repair Address correspondence to David I Watson, M.B.B.S., F.R.A.C.S., The Royal Adelaide Centre for Endoscopic Surgery, Department of Surgery, Level 6, Royal Adelaide Hospital, Adelaide, South Australia, 5000, Australia. Reprints will not be available from the authors. Accepted for publication November 16, 1995.
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and division of short gastric vessels at operation, intraoperative conversion from laparoscopic to open fundoplication, postoperative hospital stay, and three clinical outcome measures assessed 3 months after surgery (presence of solid food dysphagia, patient satisfaction score, and the expressed willingness of each patient to undergo surgery again under identical preoperative circumstances). Complications occurring within 30 days of surgery were included in the analysis, as was any requirement for further surgery related to the primary procedure at any stage after the initial surgery. Solid food dysphagia was determined using a visual analogue scale from 0 to 10 (0 = no dysphagia, 10 = severe dysphagia). For this study, an inclusive score from 4 to 10 was determined to represent moderate to severe dysphagia for solid food. The satisfaction score was determined by another visual analogue scale from 0 to 10 (0 = totally unsatisfied, 10 = totally satisfied). A score of 7 or greater was accepted as evidence of patient satisfaction with the surgical outcome. This information was then analyzed in three ways: 1. The overall institutional learning curve was determined by comparing subgroups of patients, defined by their chronological order within the overall institutional experience; procedures 1 to 20,21 to 50, 51 to 100, 101 to 150, 151 to 200,201 to 250, and 251 to 280. 2. Individual learning experiences were assessed for each surgeon by determining each patient's chronological position in each individual's experience. Operations 1 to 5 for each surgeon were combined into one group, as were operations 6 to 10, 11 to 20, 21 to 40,41 to 60, and 61 and over, respectively. 3. Because surgeons began laparoscopic fundoplication at different times during the institutional experience, the outcomes for "early" and "late" starters were compared. The first two surgeons performing laparoscopic fundoplication began clinical procedures after preliminary development work in the animal laboratory, whereas the last six surgeons were able to assist a number of procedures before being supervised by surgeons who had by then attained a large clinical experience. The first two surgeons were defined as "early" starters, whereas the last six surgeons, who all began clinical procedures 18 months or more after the "early" starters, were defined as "late" starters. The experience of three other surgeons commencing fundoplication at an intermediate stage was omitted from this analysis. Groups of patients undergoing procedures 1 to 10 and 11 to 20 for both groups of surgeons were compared to assess the effect of supervision
during a surgeon's early laparoscopic experience.
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Ann. Surg. *-August 1996
Table 1. OVERALL EXPERIENCE WITH LAPAROSCOPIC FUNDOPLICATION DETERMINED BY CHRONOLOGICAL ORDER FOR ALL CASES* Patient Nos.
Complication rate (%) Reoperation rate (%) Conversion to open(%) Weight (kg) Operating time (min) Hiatal repair (%) Short gastrics divided (%) Hospital stay (days) Dysphagia 3 mos (%) Satisfaction score 7-10 (%) Would have again (%)
1-20
21-50
30 25 20
17 13 17 78 110 33 7
72 185 5 20 5 22 88 94
4 14
83 79
51-100
101-150
151-200
201-250
251-280
8
2 6 12 78 90 31 27 3 17 90 90
12 12 10 80
10
10
6
3
4 76 77 90 48 3 35 91 94
7 84
10 10 75
90 20 0 4
33 89 95
85 90 51 3
23 88 88
80 93 30 3 NA NA NA
NA = not applicable. * Median values are given.
RESULTS The analysis of the overall institutional experience is summarized in Table 1. The complication rate (Fig. 1), early and late reoperation rates (Fig. 2), and necessity for conversion to open surgery all were greater during the first 50 procedures, particularly during the first 20 procedures performed. All parameters stabilized beyond this initial experience. Although a lower complication rate was seen only in patients 101 to 150, all other outcome measures in this group were similar to the other patient cohorts beyond the first 50 patients, suggesting that this low complication rate simply is a statistical variation
(i.e., 1/50 vs. 5/50, p = 0.20, Fisher's exact test). Median patient weight remained stable throughout the overall experience, suggesting that surgical difficulty was unchanged throughout the study. Operating time (Fig. 3) declined steadily as overall experience improved, with the most significant improvement occurring after the initial 20 procedures, despite a greater number of patients undergoing hiatal repair and division of short gastric vessels later in the study. The 3-month clinical outcomes of dysphagia, patient satisfaction score, and willingness to undergo surgery again did not improve with greater overall experience. The outcome of fundoplication analyzed according to
40-
301 30 20 0 co c
a. E0
U
0 -
a
20
L. c
0
co
0
10
0 0
1:
-Ii
1
0
1-20
21-50
51-100 101-150 151-200 201-250 251-280
Number in unit's experience Figure 1. Complication rate vs. overall experience.
1-20
21-50
51-100 101-150 151-200 201-250 251-280
Number in unit's experience
Figure 2. Reoperation rate
vs.
overall experience.
Laparoscopic Fundoplication Leaming Curve
vol. 224 - No. 2
200 l
30
201
-
c
E 20
0
E
-
-
c
a
100' 0
c a
a 0
10
E 0
'0
0
0
1-20
21-50
51-100 101-150 151-200 201-250 251-280
1-5
6-10
11-20
21-40
41-60
61+
Number in unit's experience Figure 3. Operating time vs. overall experience.
Number In surgeon's experience Figure 4. Complication rate vs. surgeon's experience.
each surgeon's individual experience is summarized in Table 2. The complication (Fig. 4) and reoperation rates (Fig. 5) were higher for patients undergoing surgery during a surgeon's first five procedures, declining to approximately O0% beyond the initial five cases (Fig. 4). A similar trend for surgical revision (Fig. 5) was seen, with the highest rate occurring during a surgeon's first five cases, and declining slowly thereafter. In contrast to the overall experience, the rate of conversion to open fundoplication did not improve with greater individual experience. Operating time (Fig. 6) declined steadily, although not as dramatically as the decline seen with the analysis of the
overall experience. The performance of hiatal repair was more likely later in both the overall and individual experiences, and division of short gastric vessels more commonly was performed later within the context of a prospectively randomized trial. Hiatal repair became a routine in an attempt to avoid the complication of paraesophageal herniation. Table 1 demonstrates no significant correlation between either routine hiatal repair or division of short gastric vessels and the outcome measures described. The 3-month outcomes of dysphagia, satisfaction score, and willingness to undergo surgery also failed to correlate with operative experience.
Table 2. COMBINED EXPERIENCE WITH LAPAROSCOPIC FUNDOPLICATION DETERMINED BY CHRONOLOGICAL ORDER FOR EACH SURGEON* Patient Numbers
No. of patients
Complication rate (%) Reoperation rate (%) Conversion to open(%) Weight (kg) Operating time (min) Hiatal repair (%) Short gastrics divided (%) Hospital stay (days) Dysphagia 3 mos (%) Satisfaction score 7-10 (%) Would have again (%) *
Median values are given.
1-5
6-10
11-20
21-40
41-60
61+
41 24 17 10 79 120 39 15 4 14 90 90
32 9 13 13 77 93 29 13 4 32 83 96
48 10 10
70 4 8.5 9 72 85 60 22 3 27 93 91
51
37 13 5 16 80 85 97 53 3 19 84 89
14
79 95 35 27 3 24 90 86
6 8 6 83 80 76 44 3 27 85 96
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Watson, Baigrie, and Jamieson
20
Ann. Surg. * August 1996
1
Table 3. EXPERIENCE WITH LAPAROSCOPIC FUNDOPLICATION PERFORMED BY "EARLY" AND "LATE" STARTERS
-1 0-
"Early" Starters
4-
0 co
10
"Late" Starters
1-10
11-20
1-10
11-20
20 25 20 20 76 185 5 20 5 33 94 94
20 15 10 20 76 95 30 10 4 24 84 84
30 17 10 7 81 100 63 21 3 23 93 100
10 10 10 30 78 120 40 50 2 20 89 89
L.
.S-
0
0.
0 cc 0
0 1-5
6-10
11-20
21-40
41-60
61 +
Number in surgeon's experience Figure 5. Reoperation rate vs. surgeon's experience
No. of patients Complication rate (%) Reoperation rate (%) Conversion to open (%) Weight (kg) Operating time (min) Hiatal repair (%) Short gastrics divided (%) Hospital stay (days) Dysphagia 3 mo (%) Satisfaction score 7-10 (%) Would have again (%) *
The experience of the "early" and "late" starters is compared in Table 3. The parameters examined for the "late" starters' first ten cases were similar to the "early" starters' second ten procedures, and better than their first ten. "Late" starters had lower complication, reoperation, and conversion rates, and much quicker initial operating times, when compared with "early" starters at comparable levels of experience. Clinical outcomes were similar at 3 months and were unrelated to either experience or surgeon. Hiatal repair and short gastric vessel division were performed more commonly by "late" starters because of alterations in surgical technique introduced later in the overall experience. This increased the rate 150
-
c
E
-
100 ID
r._
co 0. 0. ns 0
50
0
0'
1-5
6-10
11-20
21-40
41-60
Number in surgeon's experience
Figure 6. Operating time rate vs. surgeon's experience.
61 +
Median values are given
of short gastric vessel division (within the context of a prospective, randomized trial) may account for the higher median operating time of 120 minutes for the "late" starters' second ten operations.
DISCUSSION There is little doubt that a surgeon's early experience with laparoscopic procedures is associated with prolonged operating times and technical difficulties because of the need to adapt to new surgical instruments and an altered method of vision. In addition to the expense of extra operating time, early learning experiences may be associated with a higher rate of intraoperative and postoperative complications, as well as a greater likelihood of conversion from laparoscopic to open surgery. Various factors may influence the length of a learning curve and its consequences to patients. Individual learning experiences may be shortened by supervision by experienced surgeons, and shared institutional experience may reduce the learning time for the individual surgeons involved.'0 It is well accepted that the learning experience with laparoscopic cholecystectomy has been associated with an increased incidence of common bile duct injury." This risk appears to be highest within the first 10 to 15 cases of each individual's experience,'2"13 with one study suggesting that the greatest risk is within the first five procedures performed.'4 General recommendations for training have now been published by the European Association for Endoscopic
Vol. 224 - No. 2
Surgery.9 These have not specified numerical requirements for any particular procedure. The training requirements are broad and essentially offer little more than a commonsense approach. They specifically recommend either residency training in laparoscopic surgery for surgical trainees, or dedicated training programs for established surgeons. The latter programs involve attending courses, assistance or observation of procedures performed by experienced surgeons, and the performance of initial clinical procedures under the supervision of an experienced preceptor. The results reported in this study confirm an institutional learning curve for laparoscopic fundoplication of up to 50 procedures. The problems associated with this were particularly significant within the first 20 cases. By examining individual experiences, it is apparent that problems were most likely during the first five procedures performed by individual surgeons. Complication, reoperation, and conversion rates declined to approximately 10% during the next 15 procedures, with little further improvement beyond this point. The comparison of procedures performed by "early" and "late" starters confirms that proctorship can make a difference. The complication, reoperation, and conversion rates all were significantly less in the first ten cases performed by "late" starters, and operating times were reduced by 85 minutes, despite a higher rate of posterior hiatal repair. These outcomes suggest that the problems associated with the introduction of laparoscopic fundoplication can be reduced by experienced supervision during a surgeon's early cases. Table 1 highlights two changes in operative technique that have the potential to impact on adverse outcomes after laparoscopic fundoplication. A superficial analysis may associate improved outcomes with division of short gastric vessels and routine posterior hiatal repair. Although routine repair should reduce the incidence of early postoperative para-esophageal herniation,4 this problem contributed only a proportion of the postoperative morbidity analyzed, with repair not impacting greatly on the total adverse outcomes seen later in this experience. Para-esophageal herniation continued to occur sporadically in the second half of the series, despite hiatal closure, confirming that this complication is multifactorial in origin. Later in the series, short gastric vessels were divided, usually within a prospective, randomized trial, with no more than half the patients undergoing this maneuver. The influence of short gastric vessel division on operative outcome will be answered best when we report the results of this randomized trial. The data presented in this paper do not demonstrate that division has had any influence on the parameters measured, with the exception, perhaps, of operating time for "late" starters (Table 3). Is a learning curve definable for laparoscopic Nissen
Laparoscopic Fundoplication Learning Curve
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fundoplication? These results suggest that the first 20 operations at our institution and the first 5 procedures for each individual surgeon were associated with a definable learning experience. The risk of adverse outcomes did not stabilize until either 50 procedures had been performed by the institution or up to 20 had been performed by individual surgeons. Is the learning curve avoidable? The comparison of "early" and "late" starters confirms improved early outcomes with the provision of experienced supervision. Is the learning curve associated with excessive operating times? The improved times in the early procedures performed by "late" starters suggest that proctorship can save a considerable amount oftime, and that the learning problems associated with laparoscopic fundoplication can be minimized by experienced supervision of a surgeon's first 20 procedures. However, such a study does not address the question of whether, with an overall early reoperation rate of approximately 10%, we should be undertaking laparoscopic fundoplication at all. It is our belief that there remains a need for a randomized study to address this question.
References 1. Dallemagne B, Weerts JM, Jehaes C, et al. Laparoscopic Nissen fundoplication: preliminary report. Surg Laparosc Endosc 1991; 1: 138-143. 2. Cuschieri A, Hunter J, Wolfe B, et al. Multicenter prospective evaluation of laparoscopic antireflux surgery: preliminary report. Surg Endosc 1993; 7:505-5 10. 3. Weerts JM, Dallemagne B, Hamoir E, et al. Laparoscopic fundoplication: detailed analysis of 132 patients. Surg Laparosc Endosc 1993; 3:359-364. 4. Watson DI, Jamieson GG, Devitt PG, et al. Para-oesophageal hiatus hernia: an important complication of laparoscopic Nissen fundoplication. Br J Surg 1995; 82:521-523. 5. Cadiere GB. La chirurgie anti-reflux: indication, principe et apport de la coelioscopie. Rev Med Brux 1994; 15:25-30. 6. Watson DI, Jamieson GG, Mitchell PC, et al. Stenosis of the esophageal hiatus following laparoscopic fundoplication. Arch Surg
1995; 130:1014-1016. 7. Reid DB, Winning T, Bell G. Pneumothorax during laparoscopic dissection of the diaphragmatic hiatus (letter). Br J Surg 1993; 80:670. 8. Jamieson GG, Watson DI, Britten-Jones R, et al. Laparoscopic Nissen fundoplication. Ann Surg 1994; 220:137-145. 9. EAES guidelines: training and assessment of competence. Surg Endosc 1994; 8:721-722. 10. Schnieder J, Koehler RH, Brams DM, et al. A standardised approach to teaching the laparoscopic Nissen fundoplication. Surg Endosc 1995; 9:240 (abstract). 11. Schlumpf R, Klotz HP, Wehrli H, Herzog U. A nation's experience in laparoscopic cholecystectomy: prospective multicentre analysis of 3722 cases. Surg Endosc 1994; 8:35-4 1. 12. Zucker KA, Bailey RW, Gadacz TR, Imbembo AL. Laparoscopic guided cholecystectomy. Am J Surg 1991; 161:36-44. 13. Peters JH, Ellison C, Innes JT, et al. Safety and efficacy of laparoscopic cholecystectomy. Ann Surg 1991; 213:3-12. 14. Huang SM, Wu CW, Hong HT, et al. Bile duct injury and bile leakage in laparoscopic cholecystectomy. Br J Surg 1993; 80:15901592.
