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International Journal of Surgery 10 (2012) 368e372

ORIGINAL RESEARCH

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International Journal of Surgery

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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

Article history:Received 26 March 2012Received in revised form20 May 2012Accepted 28 May 2012Available online 2 June 2012

Keywords:Minimal invasive surgeryHepato-biliary surgerySingle port cholecystectomy

* Corresponding author.E-mail addresses: abdulmajid.ali@aaaht.sc

hotmail.com (A. Ali).

1743-9191/$ e see front matter � 2012 Surgical Assohttp://dx.doi.org/10.1016/j.ijsu.2012.05.017

a b s t r a c t

Background and aims: Laparoscopic techniques are rapidly evolving and trends towards a more minimallyinvasive 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-operativecomplications, operative time, postoperative complications, pain score, readmission rate and conver-sion to open amongst both groups.Methods: A retrospective review of data of patients who underwent laparoscopic cholecystectomybetween May 2009 and November 2011 was performed. All procedures were performed by a singlesurgeon.Results: A total of 184 patients underwent laparoscopic cholecystectomy. 76 patients from MPLC wereexcluded from comparison based on exclusion criteria. The remaining 62 patients in MPLC and 45patients 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) inMPLC (p ¼ 0.02). There was no conversion to open procedure. One patient in SILC group was converted toMPLC and two patients required a second port insertion. Postoperative pain-score and length of hospitalstay were comparable in both groups. One patient in each group had minor bleeding from gall bladderbed controlled with diathermy.Conclusion: SILC is a safe and feasible approach in selected patients. There was no difference incomplication rate amongst the two approaches with a longer operative time in the SILC approach.

� 2012 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

1. Introduction

In the current era of modern technology and innovation, theminimally invasive surgical approach is the standard technique formany surgical procedures. The safety and efficacy of a laparoscopicapproach over open surgery has been well established during thepast few decades.1 This is associated with a reduction in post-operative pain, shortened hospital stay and an early return towork.2

Since the development of laparoscopic technique in 1985, thisapproach has been continuously evolving and the development ofcutting edge technology has opened new windows of innovation.3

Recently, trends towards a more minimally invasive approach aswell as techniques to reduce the trauma of surgical access have led

ot.nhs.uk, abdulmajidali@

ciates Ltd. Published by Elsevier Lt

to the development of single incision and natural orifice trans-luminal endoscopic surgery (NOTES).4

Trans-umbilical single incision laparoscopic surgery (SILS) isa rapidly developing technique which has been demonstrated asa potentially “scarless” procedure.5 In this technique, multiplelaparoscopic instruments are placed either through a single portdevice with multiple conduit or through multiple closely placedports.6 This approach is technically more challenging and theunderlying principles are different to that of the conventionallaparoscopic approach,5 which is why this approach has mainlybeen adopted and promoted by surgeons with advanced conven-tional laparoscopic skills.

Initial data has shown that single incision laparoscopic chole-cystectomy (SILC) is a feasible and safe approach.7 It has beensuggested that SILC is comparable to conventional multiport lapa-roscopic cholecystectomy (MPLC) in terms of complications, rate ofconversion to open procedure and length of hospital stay.8e11

However, SILC has shown better cosmetic outcomes and patientsatisfaction.12 Hence its popularity amongst the surgeons and

d. All rights reserved.

Table 2Allocation of various groups.

Total number of patients

N=183

SILC Group N= 45

Overall MPLC GroupN= 138

Included in final analysis

High Risk MPLC N= 76

SILCN= 45

MPLCN= 62

Standard MPLC N= 62

Excluded from final analysis

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ORIGINAL RESEARCH

patients is growing; this has raised the possibility of SILC becomingan alternative approach to multiport laparoscopic cholecystectomy.Although at present, all available literature supports the feasibilityof SILC,13e23 there are only a few studies where SILC was comparedto a conventional approach.24,25 In this article we reported theoutcome of our experience of performing SILC and compared itsoutcomes with the conventional approach.

2. Patients and methods

A retrospective review of prospectively maintained data of patients undergoinglaparoscopic cholecystectomy between May 2009 and November 2011 was per-formed. The data included patients’ age, bodymass index (BMI), male to female ratioand American Society of Anaesthesiology (ASA) grade. Data regarding clinicalpresentation, surgical approach and operative time, per-operative and post-opera-tive complications, pain score, addition of further ports in SILC, conversion to openor 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 forsurgical intervention and were willing to consent for the procedure were offeredlaparoscopic cholecystectomy (Table 1). Patients with one or more of the followingconditions were regarded as high risk patients and were not considered for SILCapproach.

1. Previous upper abdominal surgery.2. Patients on warfarin.3. BMI > 40.4. Previous mesh repair of umbilical hernia.5. History of acute cholecystitis.6. Choledocholithiasis.

This high risk MPLC group (n ¼ 76) was excluded from the final analysis, asfirstly, they were not offered SILC approach and secondly they were not comparableto SILC or the rest of MPLC group due their significant previous medical and surgicalhistory. Table 2 illustrates allocation of patients in various groups depending uponthe inclusion and exclusion criteria and surgical approach.

Based on the above exclusion criteria, the remaining patients had each approachexplained. 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 andare listed in Table 3.

2.1. Statistical analysis

The statistical analysis was performed using SPSS version 17. ManneWhitney UTest was used to compare the variables in both groups.

2.2. Surgical technique

2.2.1. Multiport laparoscopic cholecystectomyA 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 ofthe patient.

For camera insertion a 12 mm Hasson’s port was introduced in the infra-umbilical area with open Hasson’s technique. A 10 mm 30� telescope was used inall procedures. All remaining ports were inserted under direct vision. A 10-mm portwas then introduced at the epigastrium for dissection purposes. A 5-mm port wasintroduced in the right side of the abdomen as lateral as possible to grasp the gallbladder fundus and retract during dissection. Another 5-mm port was introducedroughly at the mid-clavicular line in order to hold and facilitate dissection in theCalot’s triangle. The cystic duct and cystic arterywere ligated separately with the useof Weck Hem-o-lok� Ligation System. The gall bladder was dissected with hookdiathermy and retrieved via a bag through the umbilical port. The sheath was closedwith slow absorbable stitches.

Table 1Various conditions and indications for surgery.

Disease n ¼ 183

Cholecystitis/biliary colic 97Choledocholithiasis 30Gall stone pancreatitis 38Gall bladder polyp 12Acalculus cholecystitis 5Biliary dyskinesia 1

2.2.2. Single incision laparoscopic cholecystectomyThe 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 cmwas made throughthe umbilicus and the single access port was inserted through this incision. A 10 mm30� telescope was used in all SILC procedures.

Four types of single access ports were used: SILS� Port (Covidien), TriPort�Advanced Surgical Concepts (Olympus), Single Site Laparoscopy Access System(Ethicon Endosurgery) and Gelpoint (Applied Medical Systems). The first three portsystems 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 variousports (up to 3e4 ports) at a convenient place (Fig. 2).

Curved instruments were used in a few cases for traction of the gall bladder, butin the majority of cases, conventional straight instruments were used. Both types ofinstruments provided similar traction and exposure of Calot’s triangle.

A hook diathermy was used for dissection in all cases. In two cases a suture wasplaced at the gall bladder fundus and retrieved percutaneously using Endo Close�Trocar Site Closure Device (Covidien). It was kept taut by applying an artery clip to itnear the skin. Cystic duct and cystic artery were ligated separately usingWeck Hem-o-lok� Ligation System. The specimen was removed through the umbilical incisionalong with the port and the sheath was closed with slow absorbable sutures.

2.2.3. Operating teamAll SILC procedures were performed by a single consultant upper GI surgeon

with advanced laparoscopic skills. Multiport laparoscopic procedures were per-formed either by the same consultant or by a senior upper GI trainee who hadpassed the learning curve with the consultant scrubbed in theatre.

3. Results

During the study period, a total of 183 laparoscopic cholecys-tectomies were performed. 76 patients were excluded from thecomparison on the basis of exclusion criteria (Table 2). The clinicalpresentation and indication of laparoscopic cholecystectomy for allpatients is illustrated in Table 1.

Table 3Basic demographics of SILC and MPLC groups.

Demographics SILC groupN ¼ 45

MPLCN ¼ 62

Male:Female ratio 9:36 16:46Median age years 46 (range 20e73) 46.3 (range 23e67)Median BMI, kg/m2 23.6 (range 20.9e26.8) 29.1 (range 22e38)ASA grade (I:II:III) 12:24:9 15:33:14

Fig. 1. Single port with fixed channels.

Table 4Comparison of clinical outcome of SILC and MPLC groups.

Outcomes SILC group MPLC p value

Conversion to open None None e

Median hospital stay (h) 22 (range12e48)

31 h (range12e96)

p ¼ 0.2

Median operative time (min) 75 (range42e120)

58 (range26e117)

p ¼ 0.02

Median pain score2 h post op. (0e4)

0.73 0.71 p ¼ 0.2

Median pain score6 h post op. (0e4)

0.34 0.3 p ¼ 0.2

Wound infection 1/45 (2.2%) 0/62 (0%)

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ORIGINAL RESEARCH

SILC and MPLC groups were similar with respect to age, bodymass index, male to female ratio and American Society of Anaes-thesiology 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 additionalport. In the first patient, a second port was inserted while per-forming an intra-operative cholangiogram (because of history ofderanged liver function tests) and it showed no evidence ofobstruction in the common bile duct. While in the second patientthe additional port was inserted to have a better exposure of theCalot’s triangle which was obscured by adhesions between the gallbladder and the omentum. In both cases a 5 mm port was insertedin the epigastrium. One patient in SILC group was converted toMPLC due to a technical fault in the single port device leading toinability to maintain pneumoperitoneum.

Median operative time for SILC was significantly more ascompared to MPLC, 75 min (range 42e120) vs. 58 min (range26e117) p ¼ 0.02 (Table 4).

Nomajor intraoperative complications were encountered in anygroup. One patient in each group had a minor bleeding from thegall bladder bed which was controlled with diathermy. Twopatients in the SILC group and one in the MPLC group had iatro-genic gall bladder perforation during the dissection of the gallbladder from the gall bladder bed. There was no gross contami-nation of bile in both groups and washout alone was sufficient.

Fig. 2. Gelpoint (Applied Medical Systems) Single port access platform.

There was no difference in pain score and length of hospital stayamongst both groups. All patients received the same analgesia inrecovery. It was ensured that they were pain free on discharge andwere given simple non-opioid oral analgesia as a take homemedication. The pain score used is shown in Table 5.

In the follow up review, only one patient in the SILC group hadsuperficial wound infection which was managed conservativelywith oral antibiotics. There were no readmissions within 30 daysafter surgery or early port site hernias in both groups at eight weeksfollow up (Table 4).

4. Discussion

Laparoscopic cholecystectomy is considered the gold standardsurgical technique for symptomatic gall bladder disease. It isassociated with better cosmetic outcome, shorter hospital stay andrapid convalescence.2 The inspiration of performing scarless oper-ations with minimal associated pain and less tissue trauma has ledto the development of several novel techniques such as SILC, NOTESand robotic surgery.26 Since the first documented single incisionlaparoscopic procedure in 199727 and the regaining of its popularityin the past few years, the number of procedures carried out througha single port has risen dramatically.28 This rise can also be attrib-uted to the development of new operative devices which signifi-cantly improved the experience of performing SILC.29

The technical issues faced by surgeons at the beginning of theirlearning curve were loss of triangulation and difficulty in obtainingadequate exposure of the operative field. In our experience, themost important factor to overcome such challenges was theappropriate choice of the single site access device. Four differenttypes of ports were used during our initial experience of per-forming SILC. As our technique of SILC evolved, we preferred theGel based port. In our opinion this gave an increased range ofmotion to the surgeon as well as leading to reduced clashes withthe assistant and a decreased average operating time. It also offeredthe advantage of the addition of a fourth port.

There were no major intra-operative complications in the SILCgroup, supporting the notion that this is a safe and feasibleapproach. Evidence of this feasibility has already been shown ina number of other studies.30 It is worth mentioning that most of thestudies including this report, had some selection criteria in order tooffer SILC approach. The most common exclusion criteria were;

Table 5Pain score from MEWS (Modified Early Warning Score) chart.

Pain score

0 No pain at rest; no pain on movement1 No pain at rest; slight pain on movement2 Intermittent pain at rest; moderate pain on movement3 Continuous pain at rest; severe pain on movement

Fig. 3. Scar of SILC after 8 weeks of surgery.

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ORIGINAL RESEARCH

pervious surgery, acute cholecystitis, choledocholithiasis, andmorbid obesity.8,31

Recent review of SILC procedures in literature reporteda complication rate of up to 6.1% which included subcutaneoushaematoma, mesenteric injury, hepatic injury, hepatic duct injuryand bile leak.7 There was no such complication encountered in ourcohort of patients. Similarly, the published data reported an inci-dence of wound infection of up to 10%.11,30,32,33 In our study, therewas no incidence of wound infection in MPLC group and only onepatient in SILC group had superficial wound infection (2.22%) whichwas treated with a 5 day course of oral antibiotics without needingany further intervention. There is paucity of data about incisionalhernia in patients with SILC, nevertheless up to a 2% incidence ofport site hernia has been reported.30,34 No incisional hernias werefound in either group during our short term follow up, howevera longer follow up would be required to establish a more accurateincidence of port site hernias.

There was no conversion to open procedure in any group. Onepatient (2.22%) in SILC was converted toMPLC as mentioned earlier.The reason for this small conversion rate might be the fact that,during MPLC approach some procedures were completed with theuse of only three ports. We believe, this experience helped whilstadopting SILC approach and shortened the learning curve.Although the total operative time in SILC was significantly more ascompared to MPLC (p ¼ 0.02), this was mainly due to prolongedoperative times in the first 23 SILC procedures. In last 22 cases, theaverage operative time was nearly 60 min. We believe two factorscontributed to this, firstly more experience in performing SILCprocedures and secondly the Gel based port offered a better rangeof motion which reduced the operating time.

There was no statistically significant difference in the pain scoreor length of hospital stay in the two groups. Various other studieswhich measured pain score have also reported no significantdifference in SILC andMPLC approaches in relation to postoperativepain.28 SILC may not be achieving its hypothesised inspiration ofless postoperative pain which is also suggested by a recently pub-lished meta-analysis.28

One of the important features of the SILC approach was bettercosmesis. In this technique the scar gets completely concealed inthe umbilicus within two months of surgery and eventually makesit a “scarless” procedure (Fig. 3). Several other studies have alsoreported better cosmetic and body image effects along withimproved patient satisfaction after SILC through the trans-umbilical approach.35,36

Our study also has some limitations, firstly it was a retrospectivestudy and secondly we had few selection criteria which might beconsidered as a selection bias. In order to improve the reliability ofthe data, two authors reviewed all the case notes as well asprospectively kept computerised database independently. Allconflicts between the two reviewers were discussed with thesenior author and only the best possible data was included.

5. Conclusions

This study shows that SILC is a safe and feasible technique inselected cohort of patients. Therewas no difference in complicationrate and other clinical outcomes amongst SILC and MPLC. Theoperative time was longer in SILC approach but it may offer bettercosmetic outcome and patient satisfaction. In the future, it maybecome a potential alternative to the MPLC in the management ofuncomplicated gall bladder disease.

Ethical approvalNot required.

FundingNone.

Author contributionMr. 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 interestNone declared.

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