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Single incision vs. conventional multiport laparoscopic cholecystectomy: A comparison of two approaches
ORIGINAL RESEARCH International Journal of Surgery 10 (2012) 368e372
Contents lists available at SciVerse ScienceDirect
International Journal of Surgery journal homepage: www.theijs.com
Original research
Single incision vs. conventional multiport laparoscopic cholecystectomy: A comparison of two approaches Muhammad Ali Karim, Jamil Ahmed, Moustafa Mansour, Abdulmajid Ali* Department of Surgery, University Hospital Ayr, Ayrshire and Arran NHS, Dalmellington Road, KA6 6DX, United Kingdom
a r t i c l e i n f o
a b s t r a c t
Article history: Received 26 March 2012 Received in revised form 20 May 2012 Accepted 28 May 2012 Available online 2 June 2012
Background and aims: Laparoscopic techniques are rapidly evolving and trends towards a more minimally invasive approach have led to the introduction of single incision and natural orifice laparoscopic surgery. The aim of this study was to compare the outcomes of single-incision laparoscopic cholecystectomy (SILC) to conventional multiport laparoscopic cholecystectomy (MPLC). We compared intra-operative complications, operative time, postoperative complications, pain score, readmission rate and conversion to open amongst both groups. Methods: A retrospective review of data of patients who underwent laparoscopic cholecystectomy between May 2009 and November 2011 was performed. All procedures were performed by a single surgeon. Results: A total of 184 patients underwent laparoscopic cholecystectomy. 76 patients from MPLC were excluded from comparison based on exclusion criteria. The remaining 62 patients in MPLC and 45 patients in the SILC group were compared. The two groups were similar with respect to patients’ demographics and American Society of Anaesthesiology grades. The median operative time for SILC was 75 min (range 42e120) compared to 60 min (range 26e117) in MPLC (p ¼ 0.02). There was no conversion to open procedure. One patient in SILC group was converted to MPLC and two patients required a second port insertion. Postoperative pain-score and length of hospital stay were comparable in both groups. One patient in each group had minor bleeding from gall bladder bed controlled with diathermy. Conclusion: SILC is a safe and feasible approach in selected patients. There was no difference in complication rate amongst the two approaches with a longer operative time in the SILC approach. Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Minimal invasive surgery Hepato-biliary surgery Single port cholecystectomy
1. Introduction In the current era of modern technology and innovation, the minimally invasive surgical approach is the standard technique for many surgical procedures. The safety and efficacy of a laparoscopic approach over open surgery has been well established during the past few decades.1 This is associated with a reduction in postoperative pain, shortened hospital stay and an early return to work.2 Since the development of laparoscopic technique in 1985, this approach has been continuously evolving and the development of cutting edge technology has opened new windows of innovation.3 Recently, trends towards a more minimally invasive approach as well as techniques to reduce the trauma of surgical access have led
* Corresponding author. E-mail addresses: hotmail.com (A. Ali).
[email protected],
abdulmajidali@
to the development of single incision and natural orifice transluminal endoscopic surgery (NOTES).4 Trans-umbilical single incision laparoscopic surgery (SILS) is a rapidly developing technique which has been demonstrated as a potentially “scarless” procedure.5 In this technique, multiple laparoscopic instruments are placed either through a single port device with multiple conduit or through multiple closely placed ports.6 This approach is technically more challenging and the underlying principles are different to that of the conventional laparoscopic approach,5 which is why this approach has mainly been adopted and promoted by surgeons with advanced conventional laparoscopic skills. Initial data has shown that single incision laparoscopic cholecystectomy (SILC) is a feasible and safe approach.7 It has been suggested that SILC is comparable to conventional multiport laparoscopic cholecystectomy (MPLC) in terms of complications, rate of conversion to open procedure and length of hospital stay.8e11 However, SILC has shown better cosmetic outcomes and patient satisfaction.12 Hence its popularity amongst the surgeons and
1743-9191/$ e see front matter Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijsu.2012.05.017
ORIGINAL RESEARCH M.A. Karim et al. / International Journal of Surgery 10 (2012) 368e372
patients is growing; this has raised the possibility of SILC becoming an alternative approach to multiport laparoscopic cholecystectomy. Although at present, all available literature supports the feasibility of SILC,13e23 there are only a few studies where SILC was compared to a conventional approach.24,25 In this article we reported the outcome of our experience of performing SILC and compared its outcomes with the conventional approach.
369
Table 2 Allocation of various groups.
Total number of patients N=183
2. Patients and methods A retrospective review of prospectively maintained data of patients undergoing laparoscopic cholecystectomy between May 2009 and November 2011 was performed. The data included patients’ age, body mass index (BMI), male to female ratio and American Society of Anaesthesiology (ASA) grade. Data regarding clinical presentation, surgical approach and operative time, per-operative and post-operative complications, pain score, addition of further ports in SILC, conversion to open or to MPLC and readmissions within 30 days were recorded. Patients were divided into three groups; SILC, MPLC and high risk MPLC group. All patients who had symptomatic gall bladder disease, a clinical indication for surgical intervention and were willing to consent for the procedure were offered laparoscopic cholecystectomy (Table 1). Patients with one or more of the following conditions were regarded as high risk patients and were not considered for SILC approach. 1. 2. 3. 4. 5. 6.
Overall MPLC Group N= 138
SILC Group N= 45
Standard MPLC N= 62
This high risk MPLC group (n ¼ 76) was excluded from the final analysis, as firstly, they were not offered SILC approach and secondly they were not comparable to SILC or the rest of MPLC group due their significant previous medical and surgical history. Table 2 illustrates allocation of patients in various groups depending upon the inclusion and exclusion criteria and surgical approach. Based on the above exclusion criteria, the remaining patients had each approach explained. Either SILC or MPLC approach was adopted depending upon patients’ choice. Demographic details of both groups were studied carefully by two reviewers. Male:female ratio, median age, median BMI and ASA grades were comparable and are listed in Table 3. 2.1. Statistical analysis The statistical analysis was performed using SPSS version 17. ManneWhitney U Test was used to compare the variables in both groups. 2.2. Surgical technique 2.2.1. Multiport laparoscopic cholecystectomy A standard technique was used for all MPLC. This involved the patient put in a supine position, while the surgeon and the assistant both on the left hand side of the patient. For camera insertion a 12 mm Hasson’s port was introduced in the infraumbilical area with open Hasson’s technique. A 10 mm 30 telescope was used in all procedures. All remaining ports were inserted under direct vision. A 10-mm port was then introduced at the epigastrium for dissection purposes. A 5-mm port was introduced in the right side of the abdomen as lateral as possible to grasp the gall bladder fundus and retract during dissection. Another 5-mm port was introduced roughly at the mid-clavicular line in order to hold and facilitate dissection in the Calot’s triangle. The cystic duct and cystic artery were ligated separately with the use of Weck Hem-o-lokÒ Ligation System. The gall bladder was dissected with hook diathermy and retrieved via a bag through the umbilical port. The sheath was closed with slow absorbable stitches.
Table 1 Various conditions and indications for surgery. Disease
n ¼ 183
Cholecystitis/biliary colic Choledocholithiasis Gall stone pancreatitis Gall bladder polyp Acalculus cholecystitis Biliary dyskinesia
97 30 38 12 5 1
Excluded from final analysis
Included in final analysis
SILC N= 45
Previous upper abdominal surgery. Patients on warfarin. BMI > 40. Previous mesh repair of umbilical hernia. History of acute cholecystitis. Choledocholithiasis.
High Risk MPLC N= 76
MPLC N= 62
2.2.2. Single incision laparoscopic cholecystectomy The patient was placed in modified Lloyd-Davis position. The surgeon stood between the legs of the patient and the assistant on the left hand side of the patient. The umbilicus was everted, a single incision measuring 1.5e2 cm was made through the umbilicus and the single access port was inserted through this incision. A 10 mm 30 telescope was used in all SILC procedures. Four types of single access ports were used: SILSÔ Port (Covidien), TriPortÔ Advanced Surgical Concepts (Olympus), Single Site Laparoscopy Access System (Ethicon Endosurgery) and Gelpoint (Applied Medical Systems). The first three port systems have three fixed channels through which instruments were inserted (Fig. 1) while the Gelpoint is made up of a gel base which allows the insertion of various ports (up to 3e4 ports) at a convenient place (Fig. 2). Curved instruments were used in a few cases for traction of the gall bladder, but in the majority of cases, conventional straight instruments were used. Both types of instruments provided similar traction and exposure of Calot’s triangle. A hook diathermy was used for dissection in all cases. In two cases a suture was placed at the gall bladder fundus and retrieved percutaneously using Endo CloseÔ Trocar Site Closure Device (Covidien). It was kept taut by applying an artery clip to it near the skin. Cystic duct and cystic artery were ligated separately using Weck Hemo-lokÒ Ligation System. The specimen was removed through the umbilical incision along with the port and the sheath was closed with slow absorbable sutures. 2.2.3. Operating team All SILC procedures were performed by a single consultant upper GI surgeon with advanced laparoscopic skills. Multiport laparoscopic procedures were performed either by the same consultant or by a senior upper GI trainee who had passed the learning curve with the consultant scrubbed in theatre.
3. Results During the study period, a total of 183 laparoscopic cholecystectomies were performed. 76 patients were excluded from the comparison on the basis of exclusion criteria (Table 2). The clinical presentation and indication of laparoscopic cholecystectomy for all patients is illustrated in Table 1. Table 3 Basic demographics of SILC and MPLC groups. Demographics
SILC group N ¼ 45
MPLC N ¼ 62
Male:Female ratio Median age years Median BMI, kg/m2 ASA grade (I:II:III)
9:36 46 (range 20e73) 23.6 (range 20.9e26.8) 12:24:9
16:46 46.3 (range 23e67) 29.1 (range 22e38) 15:33:14
ORIGINAL RESEARCH 370
M.A. Karim et al. / International Journal of Surgery 10 (2012) 368e372 Table 4 Comparison of clinical outcome of SILC and MPLC groups. Outcomes
SILC group
MPLC
p value
Conversion to open Median hospital stay (h)
None 22 (range 12e48) 75 (range 42e120) 0.73
None 31 h (range 12e96) 58 (range 26e117) 0.71
e p ¼ 0.2
0.34
0.3
p ¼ 0.2
1/45 (2.2%)
0/62 (0%)
Median operative time (min) Median pain score 2 h post op. (0e4) Median pain score 6 h post op. (0e4) Wound infection
Fig. 1. Single port with fixed channels.
SILC and MPLC groups were similar with respect to age, body mass index, male to female ratio and American Society of Anaesthesiology grades (Table 3). None of the patients in either group had the conversion to open. Two patients in the SILC group required insertion of an additional port. In the first patient, a second port was inserted while performing an intra-operative cholangiogram (because of history of deranged liver function tests) and it showed no evidence of obstruction in the common bile duct. While in the second patient the additional port was inserted to have a better exposure of the Calot’s triangle which was obscured by adhesions between the gall bladder and the omentum. In both cases a 5 mm port was inserted in the epigastrium. One patient in SILC group was converted to MPLC due to a technical fault in the single port device leading to inability to maintain pneumoperitoneum. Median operative time for SILC was significantly more as compared to MPLC, 75 min (range 42e120) vs. 58 min (range 26e117) p ¼ 0.02 (Table 4). No major intraoperative complications were encountered in any group. One patient in each group had a minor bleeding from the gall bladder bed which was controlled with diathermy. Two patients in the SILC group and one in the MPLC group had iatrogenic gall bladder perforation during the dissection of the gall bladder from the gall bladder bed. There was no gross contamination of bile in both groups and washout alone was sufficient.
p ¼ 0.02 p ¼ 0.2
There was no difference in pain score and length of hospital stay amongst both groups. All patients received the same analgesia in recovery. It was ensured that they were pain free on discharge and were given simple non-opioid oral analgesia as a take home medication. The pain score used is shown in Table 5. In the follow up review, only one patient in the SILC group had superficial wound infection which was managed conservatively with oral antibiotics. There were no readmissions within 30 days after surgery or early port site hernias in both groups at eight weeks follow up (Table 4). 4. Discussion Laparoscopic cholecystectomy is considered the gold standard surgical technique for symptomatic gall bladder disease. It is associated with better cosmetic outcome, shorter hospital stay and rapid convalescence.2 The inspiration of performing scarless operations with minimal associated pain and less tissue trauma has led to the development of several novel techniques such as SILC, NOTES and robotic surgery.26 Since the first documented single incision laparoscopic procedure in 199727 and the regaining of its popularity in the past few years, the number of procedures carried out through a single port has risen dramatically.28 This rise can also be attributed to the development of new operative devices which significantly improved the experience of performing SILC.29 The technical issues faced by surgeons at the beginning of their learning curve were loss of triangulation and difficulty in obtaining adequate exposure of the operative field. In our experience, the most important factor to overcome such challenges was the appropriate choice of the single site access device. Four different types of ports were used during our initial experience of performing SILC. As our technique of SILC evolved, we preferred the Gel based port. In our opinion this gave an increased range of motion to the surgeon as well as leading to reduced clashes with the assistant and a decreased average operating time. It also offered the advantage of the addition of a fourth port. There were no major intra-operative complications in the SILC group, supporting the notion that this is a safe and feasible approach. Evidence of this feasibility has already been shown in a number of other studies.30 It is worth mentioning that most of the studies including this report, had some selection criteria in order to offer SILC approach. The most common exclusion criteria were;
Table 5 Pain score from MEWS (Modified Early Warning Score) chart. Pain score 0 1 2 3 Fig. 2. Gelpoint (Applied Medical Systems) Single port access platform.
No pain at rest; no pain on movement No pain at rest; slight pain on movement Intermittent pain at rest; moderate pain on movement Continuous pain at rest; severe pain on movement
ORIGINAL RESEARCH M.A. Karim et al. / International Journal of Surgery 10 (2012) 368e372
371
There was no statistically significant difference in the pain score or length of hospital stay in the two groups. Various other studies which measured pain score have also reported no significant difference in SILC and MPLC approaches in relation to postoperative pain.28 SILC may not be achieving its hypothesised inspiration of less postoperative pain which is also suggested by a recently published meta-analysis.28 One of the important features of the SILC approach was better cosmesis. In this technique the scar gets completely concealed in the umbilicus within two months of surgery and eventually makes it a “scarless” procedure (Fig. 3). Several other studies have also reported better cosmetic and body image effects along with improved patient satisfaction after SILC through the transumbilical approach.35,36 Our study also has some limitations, firstly it was a retrospective study and secondly we had few selection criteria which might be considered as a selection bias. In order to improve the reliability of the data, two authors reviewed all the case notes as well as prospectively kept computerised database independently. All conflicts between the two reviewers were discussed with the senior author and only the best possible data was included. 5. Conclusions This study shows that SILC is a safe and feasible technique in selected cohort of patients. There was no difference in complication rate and other clinical outcomes amongst SILC and MPLC. The operative time was longer in SILC approach but it may offer better cosmetic outcome and patient satisfaction. In the future, it may become a potential alternative to the MPLC in the management of uncomplicated gall bladder disease. Fig. 3. Scar of SILC after 8 weeks of surgery.
pervious surgery, acute cholecystitis, choledocholithiasis, and morbid obesity.8,31 Recent review of SILC procedures in literature reported a complication rate of up to 6.1% which included subcutaneous haematoma, mesenteric injury, hepatic injury, hepatic duct injury and bile leak.7 There was no such complication encountered in our cohort of patients. Similarly, the published data reported an incidence of wound infection of up to 10%.11,30,32,33 In our study, there was no incidence of wound infection in MPLC group and only one patient in SILC group had superficial wound infection (2.22%) which was treated with a 5 day course of oral antibiotics without needing any further intervention. There is paucity of data about incisional hernia in patients with SILC, nevertheless up to a 2% incidence of port site hernia has been reported.30,34 No incisional hernias were found in either group during our short term follow up, however a longer follow up would be required to establish a more accurate incidence of port site hernias. There was no conversion to open procedure in any group. One patient (2.22%) in SILC was converted to MPLC as mentioned earlier. The reason for this small conversion rate might be the fact that, during MPLC approach some procedures were completed with the use of only three ports. We believe, this experience helped whilst adopting SILC approach and shortened the learning curve. Although the total operative time in SILC was significantly more as compared to MPLC (p ¼ 0.02), this was mainly due to prolonged operative times in the first 23 SILC procedures. In last 22 cases, the average operative time was nearly 60 min. We believe two factors contributed to this, firstly more experience in performing SILC procedures and secondly the Gel based port offered a better range of motion which reduced the operating time.
Ethical approval Not required. Funding None. Author contribution Mr. Abdulmajid Ali e Consultant upper G.I and Bariatric surgeon (Corresponding author). Mr. Muhammad Ali Karim e Study design, Methodology, Data collection, Statistical support, Writing the manuscript. Mr. Jamil Ahmed e Revision and re-writing of the article. Mr. Mustafa Mansour e Data collection, Editing of the manuscript. Conflicts of interest None declared. References 1. Kuhry E, Schwenk W, Gaupset R, Romild U, Bonjer J. Long-term outcome of laparoscopic surgery for colorectal cancer: a cochrane systematic review of randomised controlled trials. Cancer Treat Rev 2008;34:498e504. 2. Keus F, de Jong JA, Gooszen HG, van Laarhoven CJ. Laparoscopic versus open cholecystectomy for patients with symptomatic cholecystolithiasis. Cochrane Database Syst Rev 2006;(4):CD006231. 3. Ruurda JP, Broeders IA, Simmermacher RP, Borel Rinkes IH, Van Vroonhoven TJ. Feasibility of robot-assisted laparoscopic surgery: an evaluation of 35 robotassisted laparoscopic cholecystectomies. Surg Laparosc Endosc Percutan Tech 2002;12(1):41e5. 4. Whiteford MH, Swanstrom LL. Emerging technologies including robotics and natural orifice transluminal endoscopic surgery (NOTES) colorectal surgery. J Surg Oncol 2007;96:678e83. 5. Greaves N, Nicholson J. Single incision laparoscopic surgery in general surgery: a review. Ann R Coll Surg Engl 2011;93:437e40. 6. Dutta S. Early experience with single incision laparoscopic surgery: eliminating the scar from abdominal operations. Pediatr Surg 2009;44(9):1741e5.
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7. Antoniou SA, Pointner R, Granderath FA. Single-incision laparoscopic cholecystectomy: a systematic review. Surg Endosc 2011;25(2):367e77. 8. Fransen S, Stassen L, Bouvy N. Single incision laparoscopic cholecystectomy: a review on the complications. J Minim Access Surg 2012;8(1):1e5. 9. Sinan H, Demirbas S, Ozer MT, Sucullu I, Akyol M. Single-incision laparoscopic cholecystectomy versus laparoscopic cholecystectomy: a prospective randomized study. Surg Laparosc Endosc Percutan Tech 2012;22:12e6. 10. Gangl O, Hofer W, Tomaselli F, Sautner T, Fugger R. Single incision laparoscopic cholecystectomy (SILC) versus laparoscopic cholecystectomy (LC) e a matched pair analysis. Langenbecks Arch Surg 2011;396:819e24. 11. Markar SR, Karthikesalingam A, Thrumurthy S, Muirhead L, Kinross J, Paraskeva P. Single-incision laparoscopic surgery (SILS) vs. conventional multiport cholecystectomy: systematic review and meta-analysis. Surg Endosc 2012;26(5):1205e13. 12. Phillips MS, Marks JM, Roberts K, Tacchino R, Onders R, Denoto G, et al. Intermediate results of a prospective randomized controlled trial of traditional four-port laparoscopic cholecystectomy versus single-incision laparoscopic cholecystectomy. Surg Endosc 2012;26(5):1296e303. 13. Philipp SR, Miedema BW, Thaler K. Single-incision laparoscopic cholecystectomy using conventional instruments: early experience in comparison with the gold standard. J Am Coll Surg 2009;209(5):632e7. 14. Hernandez JM, Morton CA, Ross S, Albrink M, Rosemurgy AS. Laparoendoscopic single-site cholecystectomy: the first 100 patients. Am Surg 2009;75:681e5. 15. Kirschniak A, Bollmann S, Pointner R, Granderath FA. Transumbilical singleincision laparoscopic cholecystectomy: preliminary experiences. Surg Laparosc Endosc Percutan Tech 2009;19:436e8. 16. Roberts KE, Solomon D, Duffy AJ, Bell RL. Single-incision laparoscopic cholecystectomy: a surgeon’s initial experience with 56 consecutive cases and a review of the literature. J Gastrointest Surg 2010;14:506e10. 17. Erbella Jr J, Bunch GM. Single-incision laparoscopic cholecystectomy: the first 100 outpatients. Surg Endosc 2010;24:1958e61. 18. Hirano Y, Watanabe T, Uchida T, Yoshida S, Tawaraya K, Kato H, et al. Singleincision laparoscopic cholecystectomy: single-institution experience and literature review. World J Gastroenterol 2010;16:270e4. 19. Rivas H, Varela E, Scott D. Single-incision laparoscopic cholecystectomy: initial evaluation of a large series of patients. Surg Endosc 2010;24:1403e12. 20. Brody F, Vaziri K, Kasza J, Edwards C. Single-incision laparoscopic cholecystectomy. J Am Coll Surg 2010;210:e9e13. 21. Elsey JK, Feliciano DV. Initial experience with singleincision laparoscopic cholecystectomy. J Am Coll Surg 2010;210:620e4. 22. Tacchino R, Greco F, Matera D. Single-incision laparoscopic cholecystectomy: surgery without a visible scar. Surg Endosc 2009;23:896e9.
23. Rawlings A, Hodgett SE, Matthews BD, Strasberg SM, Quasebarth M, Brunt LM. Single-incision laparoscopic cholecystectomy: initial experience with critical view of safety dissection and routine intraoperative cholangiography. J Am Coll Surg 2010;211:1e7. 24. Joseph S, Moore BT, Sorensen GB, Earley JW, Tang F, Jones P, et al. Singleincision laparoscopic cholecystectomy: a comparison with the gold standard. Surg Endosc 2011;25:3008e15. 25. Hodgett SE, Hernandez JM, Morton CA, Ross SB, Albrink M, Rosemurgy AS. Laparoendoscopic single-site (LESS) cholecystectomy. J Gastrointest Surg 2009;13:188e92. 26. Morel P, Hagen ME, Bucher P, Buchs NC, Pugin F. Robotic single-port cholecystectomy using a new platform: initial clinical experience. J Gastrointest Surg 2011;15(12):2182e6. 27. Navarra G, Pozza E, Occhionorelli S, Carcoforo P, Donini I. One-wound laparoscopic cholecystectomy. Br J Surg 1997;84:695. 28. Garg Pankaj, Thakur Jai Deep, Garg Mahak, Menon Geetha R. Single-incision laparoscopic cholecystectomy vs. conventional laparoscopic cholecystectomy: a meta-analysis of randomized controlled trials. J Gastrointest Surg 2012 [Epub ahead of print]. 29. Romanelli JR, Earle DB. Single port laparoscopic surgery: an overview. Surg Endosc 2009;23:1419e27. 30. Curcillo PG, Wu AS, Podolsky ER, Graybeal C, Katkhouda N, Saenz A, et al. Single-port-access (SPA) cholecystectomy: a multi-institutional report of the first 297 cases. Surg Endosc 2010;24(8):1854e60. 31. Aprea G, Coppola Bottazzi E, Guida F, Masone S, Persico G. Laparoendoscopic single site (LESS) versus classic video-laparoscopic cholecystectomy: a randomized prospective study. J Surg Res 2011;166(2):e109e12. 32. Lill S, Karvonen J, Hämäläinen M, Falenius V, Rantala A, Grönroos JM, et al. Adoption of single incision laparoscopic cholecystectomy in small-volume hospitals: initial experiences of 51 consecutive procedures. Scand J Surg 2011;100:164e8. 33. Erhart D, Pohnan R. Laparoscopic cholecystectomies using single incision laparoscopic surgeryeinitial experience. Rozhl Chir 2011;90:361e4. 34. Krajinovic K, Ickrath P, Germer CT, Reibetanz J. Trocar-site hernia after singleport cholecystectomy: not an exceptional complication? J Laparoendosc Adv Surg Tech A 2011;21:919e21. 35. Ma J, Cassera MA, Spaun GO, Hammill CW, Hansen PD, Aliabadi-Wahle S. Randomized controlled trial comparing single-port laparoscopic cholecystectomy and four-port laparoscopic cholecystectomy. Ann Surg 2011;254:22e7. 36. Bucher P, Pugin F, Buchs NC, Ostermann S, Morel P. Randomized clinical trial of laparoendoscopic single-site versus conventional laparoscopic cholecystectomy. Br J Surg 2011;98(12):1695e702.
Contents lists available at SciVerse ScienceDirect
International Journal of Surgery journal homepage: www.theijs.com
Original research
Single incision vs. conventional multiport laparoscopic cholecystectomy: A comparison of two approaches Muhammad Ali Karim, Jamil Ahmed, Moustafa Mansour, Abdulmajid Ali* Department of Surgery, University Hospital Ayr, Ayrshire and Arran NHS, Dalmellington Road, KA6 6DX, United Kingdom
a r t i c l e i n f o
a b s t r a c t
Article history: Received 26 March 2012 Received in revised form 20 May 2012 Accepted 28 May 2012 Available online 2 June 2012
Background and aims: Laparoscopic techniques are rapidly evolving and trends towards a more minimally invasive approach have led to the introduction of single incision and natural orifice laparoscopic surgery. The aim of this study was to compare the outcomes of single-incision laparoscopic cholecystectomy (SILC) to conventional multiport laparoscopic cholecystectomy (MPLC). We compared intra-operative complications, operative time, postoperative complications, pain score, readmission rate and conversion to open amongst both groups. Methods: A retrospective review of data of patients who underwent laparoscopic cholecystectomy between May 2009 and November 2011 was performed. All procedures were performed by a single surgeon. Results: A total of 184 patients underwent laparoscopic cholecystectomy. 76 patients from MPLC were excluded from comparison based on exclusion criteria. The remaining 62 patients in MPLC and 45 patients in the SILC group were compared. The two groups were similar with respect to patients’ demographics and American Society of Anaesthesiology grades. The median operative time for SILC was 75 min (range 42e120) compared to 60 min (range 26e117) in MPLC (p ¼ 0.02). There was no conversion to open procedure. One patient in SILC group was converted to MPLC and two patients required a second port insertion. Postoperative pain-score and length of hospital stay were comparable in both groups. One patient in each group had minor bleeding from gall bladder bed controlled with diathermy. Conclusion: SILC is a safe and feasible approach in selected patients. There was no difference in complication rate amongst the two approaches with a longer operative time in the SILC approach. Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Minimal invasive surgery Hepato-biliary surgery Single port cholecystectomy
1. Introduction In the current era of modern technology and innovation, the minimally invasive surgical approach is the standard technique for many surgical procedures. The safety and efficacy of a laparoscopic approach over open surgery has been well established during the past few decades.1 This is associated with a reduction in postoperative pain, shortened hospital stay and an early return to work.2 Since the development of laparoscopic technique in 1985, this approach has been continuously evolving and the development of cutting edge technology has opened new windows of innovation.3 Recently, trends towards a more minimally invasive approach as well as techniques to reduce the trauma of surgical access have led
* Corresponding author. E-mail addresses: hotmail.com (A. Ali).
[email protected],
abdulmajidali@
to the development of single incision and natural orifice transluminal endoscopic surgery (NOTES).4 Trans-umbilical single incision laparoscopic surgery (SILS) is a rapidly developing technique which has been demonstrated as a potentially “scarless” procedure.5 In this technique, multiple laparoscopic instruments are placed either through a single port device with multiple conduit or through multiple closely placed ports.6 This approach is technically more challenging and the underlying principles are different to that of the conventional laparoscopic approach,5 which is why this approach has mainly been adopted and promoted by surgeons with advanced conventional laparoscopic skills. Initial data has shown that single incision laparoscopic cholecystectomy (SILC) is a feasible and safe approach.7 It has been suggested that SILC is comparable to conventional multiport laparoscopic cholecystectomy (MPLC) in terms of complications, rate of conversion to open procedure and length of hospital stay.8e11 However, SILC has shown better cosmetic outcomes and patient satisfaction.12 Hence its popularity amongst the surgeons and
1743-9191/$ e see front matter Ó 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijsu.2012.05.017
ORIGINAL RESEARCH M.A. Karim et al. / International Journal of Surgery 10 (2012) 368e372
patients is growing; this has raised the possibility of SILC becoming an alternative approach to multiport laparoscopic cholecystectomy. Although at present, all available literature supports the feasibility of SILC,13e23 there are only a few studies where SILC was compared to a conventional approach.24,25 In this article we reported the outcome of our experience of performing SILC and compared its outcomes with the conventional approach.
369
Table 2 Allocation of various groups.
Total number of patients N=183
2. Patients and methods A retrospective review of prospectively maintained data of patients undergoing laparoscopic cholecystectomy between May 2009 and November 2011 was performed. The data included patients’ age, body mass index (BMI), male to female ratio and American Society of Anaesthesiology (ASA) grade. Data regarding clinical presentation, surgical approach and operative time, per-operative and post-operative complications, pain score, addition of further ports in SILC, conversion to open or to MPLC and readmissions within 30 days were recorded. Patients were divided into three groups; SILC, MPLC and high risk MPLC group. All patients who had symptomatic gall bladder disease, a clinical indication for surgical intervention and were willing to consent for the procedure were offered laparoscopic cholecystectomy (Table 1). Patients with one or more of the following conditions were regarded as high risk patients and were not considered for SILC approach. 1. 2. 3. 4. 5. 6.
Overall MPLC Group N= 138
SILC Group N= 45
Standard MPLC N= 62
This high risk MPLC group (n ¼ 76) was excluded from the final analysis, as firstly, they were not offered SILC approach and secondly they were not comparable to SILC or the rest of MPLC group due their significant previous medical and surgical history. Table 2 illustrates allocation of patients in various groups depending upon the inclusion and exclusion criteria and surgical approach. Based on the above exclusion criteria, the remaining patients had each approach explained. Either SILC or MPLC approach was adopted depending upon patients’ choice. Demographic details of both groups were studied carefully by two reviewers. Male:female ratio, median age, median BMI and ASA grades were comparable and are listed in Table 3. 2.1. Statistical analysis The statistical analysis was performed using SPSS version 17. ManneWhitney U Test was used to compare the variables in both groups. 2.2. Surgical technique 2.2.1. Multiport laparoscopic cholecystectomy A standard technique was used for all MPLC. This involved the patient put in a supine position, while the surgeon and the assistant both on the left hand side of the patient. For camera insertion a 12 mm Hasson’s port was introduced in the infraumbilical area with open Hasson’s technique. A 10 mm 30 telescope was used in all procedures. All remaining ports were inserted under direct vision. A 10-mm port was then introduced at the epigastrium for dissection purposes. A 5-mm port was introduced in the right side of the abdomen as lateral as possible to grasp the gall bladder fundus and retract during dissection. Another 5-mm port was introduced roughly at the mid-clavicular line in order to hold and facilitate dissection in the Calot’s triangle. The cystic duct and cystic artery were ligated separately with the use of Weck Hem-o-lokÒ Ligation System. The gall bladder was dissected with hook diathermy and retrieved via a bag through the umbilical port. The sheath was closed with slow absorbable stitches.
Table 1 Various conditions and indications for surgery. Disease
n ¼ 183
Cholecystitis/biliary colic Choledocholithiasis Gall stone pancreatitis Gall bladder polyp Acalculus cholecystitis Biliary dyskinesia
97 30 38 12 5 1
Excluded from final analysis
Included in final analysis
SILC N= 45
Previous upper abdominal surgery. Patients on warfarin. BMI > 40. Previous mesh repair of umbilical hernia. History of acute cholecystitis. Choledocholithiasis.
High Risk MPLC N= 76
MPLC N= 62
2.2.2. Single incision laparoscopic cholecystectomy The patient was placed in modified Lloyd-Davis position. The surgeon stood between the legs of the patient and the assistant on the left hand side of the patient. The umbilicus was everted, a single incision measuring 1.5e2 cm was made through the umbilicus and the single access port was inserted through this incision. A 10 mm 30 telescope was used in all SILC procedures. Four types of single access ports were used: SILSÔ Port (Covidien), TriPortÔ Advanced Surgical Concepts (Olympus), Single Site Laparoscopy Access System (Ethicon Endosurgery) and Gelpoint (Applied Medical Systems). The first three port systems have three fixed channels through which instruments were inserted (Fig. 1) while the Gelpoint is made up of a gel base which allows the insertion of various ports (up to 3e4 ports) at a convenient place (Fig. 2). Curved instruments were used in a few cases for traction of the gall bladder, but in the majority of cases, conventional straight instruments were used. Both types of instruments provided similar traction and exposure of Calot’s triangle. A hook diathermy was used for dissection in all cases. In two cases a suture was placed at the gall bladder fundus and retrieved percutaneously using Endo CloseÔ Trocar Site Closure Device (Covidien). It was kept taut by applying an artery clip to it near the skin. Cystic duct and cystic artery were ligated separately using Weck Hemo-lokÒ Ligation System. The specimen was removed through the umbilical incision along with the port and the sheath was closed with slow absorbable sutures. 2.2.3. Operating team All SILC procedures were performed by a single consultant upper GI surgeon with advanced laparoscopic skills. Multiport laparoscopic procedures were performed either by the same consultant or by a senior upper GI trainee who had passed the learning curve with the consultant scrubbed in theatre.
3. Results During the study period, a total of 183 laparoscopic cholecystectomies were performed. 76 patients were excluded from the comparison on the basis of exclusion criteria (Table 2). The clinical presentation and indication of laparoscopic cholecystectomy for all patients is illustrated in Table 1. Table 3 Basic demographics of SILC and MPLC groups. Demographics
SILC group N ¼ 45
MPLC N ¼ 62
Male:Female ratio Median age years Median BMI, kg/m2 ASA grade (I:II:III)
9:36 46 (range 20e73) 23.6 (range 20.9e26.8) 12:24:9
16:46 46.3 (range 23e67) 29.1 (range 22e38) 15:33:14
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M.A. Karim et al. / International Journal of Surgery 10 (2012) 368e372 Table 4 Comparison of clinical outcome of SILC and MPLC groups. Outcomes
SILC group
MPLC
p value
Conversion to open Median hospital stay (h)
None 22 (range 12e48) 75 (range 42e120) 0.73
None 31 h (range 12e96) 58 (range 26e117) 0.71
e p ¼ 0.2
0.34
0.3
p ¼ 0.2
1/45 (2.2%)
0/62 (0%)
Median operative time (min) Median pain score 2 h post op. (0e4) Median pain score 6 h post op. (0e4) Wound infection
Fig. 1. Single port with fixed channels.
SILC and MPLC groups were similar with respect to age, body mass index, male to female ratio and American Society of Anaesthesiology grades (Table 3). None of the patients in either group had the conversion to open. Two patients in the SILC group required insertion of an additional port. In the first patient, a second port was inserted while performing an intra-operative cholangiogram (because of history of deranged liver function tests) and it showed no evidence of obstruction in the common bile duct. While in the second patient the additional port was inserted to have a better exposure of the Calot’s triangle which was obscured by adhesions between the gall bladder and the omentum. In both cases a 5 mm port was inserted in the epigastrium. One patient in SILC group was converted to MPLC due to a technical fault in the single port device leading to inability to maintain pneumoperitoneum. Median operative time for SILC was significantly more as compared to MPLC, 75 min (range 42e120) vs. 58 min (range 26e117) p ¼ 0.02 (Table 4). No major intraoperative complications were encountered in any group. One patient in each group had a minor bleeding from the gall bladder bed which was controlled with diathermy. Two patients in the SILC group and one in the MPLC group had iatrogenic gall bladder perforation during the dissection of the gall bladder from the gall bladder bed. There was no gross contamination of bile in both groups and washout alone was sufficient.
p ¼ 0.02 p ¼ 0.2
There was no difference in pain score and length of hospital stay amongst both groups. All patients received the same analgesia in recovery. It was ensured that they were pain free on discharge and were given simple non-opioid oral analgesia as a take home medication. The pain score used is shown in Table 5. In the follow up review, only one patient in the SILC group had superficial wound infection which was managed conservatively with oral antibiotics. There were no readmissions within 30 days after surgery or early port site hernias in both groups at eight weeks follow up (Table 4). 4. Discussion Laparoscopic cholecystectomy is considered the gold standard surgical technique for symptomatic gall bladder disease. It is associated with better cosmetic outcome, shorter hospital stay and rapid convalescence.2 The inspiration of performing scarless operations with minimal associated pain and less tissue trauma has led to the development of several novel techniques such as SILC, NOTES and robotic surgery.26 Since the first documented single incision laparoscopic procedure in 199727 and the regaining of its popularity in the past few years, the number of procedures carried out through a single port has risen dramatically.28 This rise can also be attributed to the development of new operative devices which significantly improved the experience of performing SILC.29 The technical issues faced by surgeons at the beginning of their learning curve were loss of triangulation and difficulty in obtaining adequate exposure of the operative field. In our experience, the most important factor to overcome such challenges was the appropriate choice of the single site access device. Four different types of ports were used during our initial experience of performing SILC. As our technique of SILC evolved, we preferred the Gel based port. In our opinion this gave an increased range of motion to the surgeon as well as leading to reduced clashes with the assistant and a decreased average operating time. It also offered the advantage of the addition of a fourth port. There were no major intra-operative complications in the SILC group, supporting the notion that this is a safe and feasible approach. Evidence of this feasibility has already been shown in a number of other studies.30 It is worth mentioning that most of the studies including this report, had some selection criteria in order to offer SILC approach. The most common exclusion criteria were;
Table 5 Pain score from MEWS (Modified Early Warning Score) chart. Pain score 0 1 2 3 Fig. 2. Gelpoint (Applied Medical Systems) Single port access platform.
No pain at rest; no pain on movement No pain at rest; slight pain on movement Intermittent pain at rest; moderate pain on movement Continuous pain at rest; severe pain on movement
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There was no statistically significant difference in the pain score or length of hospital stay in the two groups. Various other studies which measured pain score have also reported no significant difference in SILC and MPLC approaches in relation to postoperative pain.28 SILC may not be achieving its hypothesised inspiration of less postoperative pain which is also suggested by a recently published meta-analysis.28 One of the important features of the SILC approach was better cosmesis. In this technique the scar gets completely concealed in the umbilicus within two months of surgery and eventually makes it a “scarless” procedure (Fig. 3). Several other studies have also reported better cosmetic and body image effects along with improved patient satisfaction after SILC through the transumbilical approach.35,36 Our study also has some limitations, firstly it was a retrospective study and secondly we had few selection criteria which might be considered as a selection bias. In order to improve the reliability of the data, two authors reviewed all the case notes as well as prospectively kept computerised database independently. All conflicts between the two reviewers were discussed with the senior author and only the best possible data was included. 5. Conclusions This study shows that SILC is a safe and feasible technique in selected cohort of patients. There was no difference in complication rate and other clinical outcomes amongst SILC and MPLC. The operative time was longer in SILC approach but it may offer better cosmetic outcome and patient satisfaction. In the future, it may become a potential alternative to the MPLC in the management of uncomplicated gall bladder disease. Fig. 3. Scar of SILC after 8 weeks of surgery.
pervious surgery, acute cholecystitis, choledocholithiasis, and morbid obesity.8,31 Recent review of SILC procedures in literature reported a complication rate of up to 6.1% which included subcutaneous haematoma, mesenteric injury, hepatic injury, hepatic duct injury and bile leak.7 There was no such complication encountered in our cohort of patients. Similarly, the published data reported an incidence of wound infection of up to 10%.11,30,32,33 In our study, there was no incidence of wound infection in MPLC group and only one patient in SILC group had superficial wound infection (2.22%) which was treated with a 5 day course of oral antibiotics without needing any further intervention. There is paucity of data about incisional hernia in patients with SILC, nevertheless up to a 2% incidence of port site hernia has been reported.30,34 No incisional hernias were found in either group during our short term follow up, however a longer follow up would be required to establish a more accurate incidence of port site hernias. There was no conversion to open procedure in any group. One patient (2.22%) in SILC was converted to MPLC as mentioned earlier. The reason for this small conversion rate might be the fact that, during MPLC approach some procedures were completed with the use of only three ports. We believe, this experience helped whilst adopting SILC approach and shortened the learning curve. Although the total operative time in SILC was significantly more as compared to MPLC (p ¼ 0.02), this was mainly due to prolonged operative times in the first 23 SILC procedures. In last 22 cases, the average operative time was nearly 60 min. We believe two factors contributed to this, firstly more experience in performing SILC procedures and secondly the Gel based port offered a better range of motion which reduced the operating time.
Ethical approval Not required. Funding None. Author contribution Mr. Abdulmajid Ali e Consultant upper G.I and Bariatric surgeon (Corresponding author). Mr. Muhammad Ali Karim e Study design, Methodology, Data collection, Statistical support, Writing the manuscript. Mr. Jamil Ahmed e Revision and re-writing of the article. Mr. Mustafa Mansour e Data collection, Editing of the manuscript. Conflicts of interest None declared. References 1. Kuhry E, Schwenk W, Gaupset R, Romild U, Bonjer J. Long-term outcome of laparoscopic surgery for colorectal cancer: a cochrane systematic review of randomised controlled trials. Cancer Treat Rev 2008;34:498e504. 2. Keus F, de Jong JA, Gooszen HG, van Laarhoven CJ. Laparoscopic versus open cholecystectomy for patients with symptomatic cholecystolithiasis. Cochrane Database Syst Rev 2006;(4):CD006231. 3. Ruurda JP, Broeders IA, Simmermacher RP, Borel Rinkes IH, Van Vroonhoven TJ. Feasibility of robot-assisted laparoscopic surgery: an evaluation of 35 robotassisted laparoscopic cholecystectomies. Surg Laparosc Endosc Percutan Tech 2002;12(1):41e5. 4. Whiteford MH, Swanstrom LL. Emerging technologies including robotics and natural orifice transluminal endoscopic surgery (NOTES) colorectal surgery. J Surg Oncol 2007;96:678e83. 5. Greaves N, Nicholson J. Single incision laparoscopic surgery in general surgery: a review. Ann R Coll Surg Engl 2011;93:437e40. 6. Dutta S. Early experience with single incision laparoscopic surgery: eliminating the scar from abdominal operations. Pediatr Surg 2009;44(9):1741e5.
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