Two-port mini laparoscopic cholecystectomy compared to standard four-port laparoscopic cholecystectomy.

INTRODUCTION: Two-port mini laparoscopic cholecystectomy (LC) has been proposed as a safe and feasible technique. However, there are limited studies to evaluate the effectiveness of the procedure. This study is a prospective randomised trial to compare the standard four-port LC with two-port mini LC.
MATERIALS AND METHODS: A total of 116 consecutive patients undergoing LC were randomised to four-port/two-port mini LC. In two-port mini LC, a 10-mm umbilical and a 5-mm epigastric port were used. Outcomes measured were duration and difficulty of operation, post-operative pain, analgesia requirements, post-operative stay, complications and cosmetic score at 30 days.
RESULTS: Out of 116 patients, the ratio of M:F was 11:92, with mean age 40.79 ± 12.6 years. Twelve patients (nine in four-port group and three in two-port group) were lost to follow-up. The mean operative time were similar (P = 0.727). Post-operative pain was significantly low in the two-port group at up to 24 hrs (P = 0.023). The overall analgesia requirements (P = 0.003) and return to daily activity (P = 0.00) were significantly lower in two-port group. The cosmesis score of the two-port group was better than four-port group (P = 0.00). However, the length of hospital stay (P = 0.760) and complications (P = 0.247) were similar between the two groups.
CONCLUSION: Two-port mini LC resulted in reduced pain, need for analgesia, and improved cosmesis without increasing the operative time and complication rates compared to that in four-port LC. Thus, it can be recommended in selected patients.

RCT Entities:   Population Interventions Outcomes

INTRODUCTION

Laparoscopic cholecystectomy (LC) is the gold standard for the removal of gall bladder.[1] The main advantages of laparoscopic surgery include better cosmetic results, decreased post-operative pain and faster functional recovery.[1] Innovative techniques of Natural Orifice Endoscopic Surgery (NOTES),[2] Single-Incision Laparoscopic surgery (SILS)[345] along with two-port[6] and three-port[7] laparoscopic surgeries have been applied to gall bladder removal as a step towards even lesser invasive procedures than the conventional four-port surgery. These newer techniques represent the advent of essentially scarless, more pain-free, better cosmesis and early return of function for the patient.

SILS or Single — Port-Access [SPA] proposes to offer an even better cosmesis since it leaves no visible scar as it is hidden in the umbilicus. However, the technique is more demanding as dissection becomes more difficult due to clashing of instruments, loss of normal triangulation, restricted vision and depth of dissection. Special large port, angulated instruments and scopes are needed for better dissection. All these factors lead to a steeper learning curve and increase the risk of wound-related complications including hernia formation.[4]

In two-port mini LC/four-port LC, compared to SILS, surgery becomes much easier due to restoration of triangulation, learning curve becomes shorter, causes minimal violation of anterior abdomen leading to lesser post-operative pain and cosmesis is comparable.[8] With the newer techniques, the need for more sophisticated instruments escalates the cost of surgery and limits the use of these minimally invasive techniques to a few centres. Two-port mini LC scores over the conventional techniques as it requires minimal new instruments and can be performed at all laparoscopic centres without any new cost inputs, and simultaneously achieve the goal of minimal access surgery.

The present study was carried out as very limited data was available for evaluating the feasibility of this technique in LC compared to the conventional laparoscopic surgery.

MATERIALS AND METHODS

The study was carried out over a period of 18 months in a single surgical unit at a teaching hospital in New Delhi. All patients with gallbladder stones attending the surgical OPD were evaluated. All symptomatic patients with BMI <30 kg/m2 , ASA Grade I/II, Age >12 yrs were included in the study. Patients with BMI >30 kg/m2 , previous major abdominal surgeries, ASA Grade III/IV, refused consent, features of acute cholecystitis, choledocolithiasis, pancreatitis and malignancy on clinical and USG examination were excluded from the study.

Evaluation of patients included a detailed history, a thorough physical examination and investigations which included a complete haemogram, kidney function test (KFT): Blood urea, serum creatinine, liver function test (LFT) — serum bilirubin, ALT/AST, alkaline phosphatase, serum proteins — albumin, globulin, serum electrolytes, Na+/K+ and random blood sugar (RBS). A USG abdomen was done to confirm the gallbladder calculi, measure its wall thickness, common bile duct (CBD) diameter and stones and features of acute inflammation or malignancy.

An informed written and verbal consent explaining that he/she has understood the procedure was obtained at least one day prior to surgery. It was a double-blinded randomised study, and patients were assigned to a particular group based on closed envelop randomisation method just before the beginning of surgery. Patients were divided into two groups; Group A — patients undergoing standard four-port LC; and Group B — patients undergoing two-port mini LC.

The surgery was performed by a team of two surgeons with adequate experience in a single surgical unit.

Operative Technique

Pneumoperitoneum was created using CO2 gas by placing a Veress needle followed by placement of a transumbilical/subumbilical/supraumbilical 10-mm port with abdominal pressure maintained at 12 mm Hg. A zero degree 10-mm laparoscope was passed and the operative difficulty was assessed based on the degree of inflammation, adhesions, condition of gall bladder wall, presence of fistula formation with neighbouring organs/structures (duodenum, CBD, colon, stomach, etc).

Four-Port LC

The patient was placed in reverse Trendelenburg position and tilted to the left and surgery proceeded as standard procedure. A 10-mm trocar was placed in the epigastrium to the right of the falciform ligament with two additional 5-mm ports in the right upper abdomen two finger breadths below the costal margin in midclavicular line and anterior/midaxillary line at the level or just below the umbilicus. Dissection of the gallbladder was performed by the standard technique by first grasping and lifting the fundus, followed by dissection of the cystic duct and artery. Once the ‘critical view’ of these structures was obtained, these were clipped and divided. The gallbladder was removed from its bed using electrocautery and retrieved through the epigastric port.

Two-Port Mini LC

Following the placement of umbilical port, instead of a 10-mm, a 5-mm epigastric port was placed. Two special 2.3-mm alligator graspers (Stryker Corporation, USA) [Figure 1] were used transabdominally for grasping the fundus [Figure 2] and Hartmann's pouch of the gallbladder for its retraction and manipulation [Figure 3], respectively. Using the standard Maryland laparoscopic instrument, the cystic duct and artery were dissected as in the four-port technique [Figure 4]. For clipping the cystic duct and artery, a 5-mm clip applicator was used with 200-mm clips. In case of wider cystic duct, single-hand suturing of the duct was done with 2/0 silk. Alternatively, the position and size of the scope was changed to a 5-mm 30° scope through the epigastric port and clips (300/400 mm) were applied through the 10-mm umbilical port. The structures were divided and dissection proceeded by reversing the laparoscope and dissecting instruments to their original sites. Gallbladder specimen was retrieved through the umbilical port by rail-road technique or using 5-mm 30° scope through the epigastric port and 10-mm jaw forceps from the umbilical port.

Figure 1

Needlescopic grasper used in ‘two-port’ laparoscopic cholecystectomy

Figure 2

First grasper to retract fundus

Figure 3

Second grasper at the neck of gallbladder

Figure 4

Cystic duct dissection and division

The ports were closed in layers — sheath with 2/0 vicryl and skin with 3/0 nylon in both procedures.

At completion, 10 ml of 0.25% bupivacaine was left in the gallbladder fossa and the port site was infiltrated with 1 ml of 0.25% bupivacaine as local anesthetic. If in any patient, for any reason, there was difficulty in proceeding with two ports, additional port(s) was used or the procedure was converted to open cholecystectomy. The patients were followed up for 30 days after discharge.

To compare the two methods, following data were noted:

Time of operation: Counted from “skin to skin”, i.e., from first incision to the end of closure of the final wound.

Conversion from two-port LC to four-port LC/open cholecystectomy.

Complications: CBD injury, hepatic injury/bleed, biliary/stone spillage, bowel injury, vascular injury or any other complication up to 30 days post-operatively.

Post-operative pain: Site; severity of pain as assessed by Visual Analog Scale (VAS) at 2, 4, 6,812 and 24 hours; and total 24 hours.

Analgesia requirement of the patient.

Lengths of post-operative hospital stay (in hours).

Cosmesis: Assessed at the end of 30 days by the patient and independent nurse in the ward/OPD. Each was asked to rate cosmesis on a scale of 1 (worst) to 10 (best). The mean of both the patients' score and nurse's score was taken as the final score [Figure 5].

Figure 5

Post-operative scar in ‘two port’ laparoscopic cholecystectomy. The 10-mm scar is hidden in the umbilicus (black arrow) and small epigastric scar (white arrow)

Statistical Analysis

Parametric summary statistics were presented as means with standard deviation. Non-parametric statistics were presented as medians with interquartile ranges. Categorical data were analysed with Chi-square tests. Independent t was used to test the means using the SPSS software package version 19.0 (SPSS Inc., Chicago, Il, USA).

RESULTS

A total of 125 patients were operated during the study period; five patients were excluded as they underwent additional procedure. Four patients had an American Society of Anesthesiologists (ASA) grade more than II and were not included in the study as per the study protocols. A total of 116 patients were included in the study. Fifty-eight patients were randomised into the four-port and two-port group using the closed envelope technique. Twelve patients, nine in the four-port group and three in the two-port group were lost to follow-up. A total of 103 patients were left in the study group for the final analysis [Chart 1- CONSORT FLOW CHART].

Chart 1

CONSORT Flow chart

The mean age, sex ratio, ASA grades and BMI between the two groups were comparable [Table 1].

Table 1

Patient demographics

The mean operative times between the two groups were not statistically significant (Four port LC - 49.90 min; Two port mini LC - 51.30, P = 0.727) [Table 2]. The operative difficulty score showed that both groups were comparable in terms of difficulty levels (P = 0.303) [Table 2]. The mean incidence of intra-operative complications such as bleeding from liver bed (Four port LC - 2 [4.16%], Two port mini LC - 3 [5.45%]) and bile spillage (Four port LC - 13 [27.08%], Two port LC - 11 [20%]) were not significantly different between both groups; however, there was a single event of CBD injury in the two-port group, which was recognised intra-operatively and repaired [Table 3].

Table 2

Comparison of parameters between four-port and two-port group

Table 3

Incidence of individual intra-operative complications in the two groups

One patient from two port mini LC group required open cholecystectomy (0.18%), and three patients needed conversion to four port LC (5.45%). The conversion to open cholecystectomy was required for a CBD injury, while the conversions to four port LC were due to difficult anatomy and adhesions around the GB fossa. In the Four port LC group, two patients were converted to open cholecystectomy (4.16%) for dense adhesions around the gallbladder.

Table 4 shows the mean post-operative pain scores (as assessed by VAS) of both groups. The average pain scores at 2, 4, 6, 8, 12 and 24 hours on post-operative day 1 was significantly lower in two port mini LC than in four port LC. However, after first 24 hours, there was no difference in the pain. The parenteral analgesic requirement (i.m Diclofenac 75 mg) in the two port mini LC was significantly lower than four port LC for the first 24 hrs; 2.85 doses vs. 2.31 doses (P = 0.003).

Table 4

Mean pain scores patients of both groups at regular intervals

The mean duration of hospital stay was similar in both groups; four port LC – 25.52 hrs, two port mini LC – 24.91 hrs (P = 0.760). The patients' return to daily activities at home was faster by almost one day and was statistically significant (Four port LC - 4.25 days, Two port mini LC - 5.17 days; P < 0.001).

The cosmetic score on a scale of 1-10 (mean of both patients and the independent nurse' score) was significantly better in the two port mini LC compared to four port LC at the end of 30 days (Four port LC 5.90 days vs. Two port mini LC 7.5 days; P < 0.001).

DISCUSSION

The evolution of surgery of gallbladder from Langenbuch's first cholecystectomy with a hospital stay of six weeks into a day-care specialty following the introduction of LC is indeed fascinating.[9] The main thrust has been on the reduction of pain and improving cosmesis throughout the history of cholecystectomy. In fact, post-operative pain is the limiting factor for the delay in discharge in day-care cholecystectomies. The idea of scarless surgeries has led to increased acceptance of the procedures among patients. Reduced port surgeries may seem more costly procedures but by achieving higher bed-patient ratio, reduced parental analgesia and with one less assistant they may indeed be cost-effective on a long-term basis. Two-port mini LC using conventional instruments can afford the benefits of reduced port surgeries without cost escalation.

The main advantage of two-port mini LC as described in the present study is the ease of performing the technique, and principles of surgery remain similar to the conventional four-port LC. Compared to this, other reduced port surgeries such as NOTES[2] and SILS[34] are technically more demanding as dissection becomes more difficult due to clashing of instruments, loss of normal triangulation, restricted vision and depth of dissection. Special large port, angulated instruments and scopes are needed for better dissection. All these factors lead to a steeper learning curve, and hence, operating time.[4]

The port sizes in our study were 10 + 5 + 2.3 + 2.3. Various port sizes have been used by other researchers, which might require more sophisticated instruments [Table 5]. There is no standard size of the ports, and we chose the above size simply to use the normal four port LC instruments.

Table 5

Comparison of various variables in two-port surgeries

In the present study, the use of two ports and graspers did not increase the operative difficulty as the mean duration of the procedures was similar in both groups. Operative time varies with different studies as few require less and few more than the conventional technique.[1011121314] The operative difficulty based on the status of gallbladder, adhesions around the gallbladder fossa and elsewhere in the abdomen, Calot's triangle and cystic duct anatomy was similar in both groups in our study.

The incidence of intra-operative and post-operative complications was similar in comparison to other studies; however, it is not reported by any other study. The present study had a single incident of CBD injury in the two port mini LC. It would be difficult to attribute the same to the use of two ports, as it was the only case which happened in the entire study group. Besides this, no other major intra-operative complication was noted in the entire study group. The conversion rates from two port mini LC to four port LC and open cholecystectomy in many studies are in the range of 23% to 38%.[131516] The conversion rates from two port mini LC in our study were less than the other studies. The main reasons in our study for conversions were difficult anatomy due to dense inflammation from cholecystitis and one CBD injury. Instrument failure was seen in few early studies, and we had no episode of instrument failure. A planned two-port surgery must be given up in the event of such difficult anatomy on initial diagnostic exploration or hindrance to proceed further during the course of the dissection.[1718] A conversion can be with additional ports or with open cholecystectomy.

Reduced pain due to reduced number and sizes of the ports has been established by researchers such as Cheah et al. and Bisgaard et al.[1119] By omitting two 5-mm ports resulted in decreased post-operative pain in the first 24 hours. This has been observed by many other studies, which have also shown reduced pain in reduced port surgery compared to conventional four-port LC. The post-operative pain was assessed by VAS, which is the same method used in other studies. The pain was recorded during the patient's stay at hospital. The post-operative pain in our series was significantly lower in the first 24 hrs only, and not later. However, a large cohort of the study was discharged by 24 hrs (Group A 89.5%, Group B 92.7%). This was further supported by less requirement of analgesia and the early return to their activities in the two port mini LC in contrast to the four port LC.

The mean length of hospital stay was same in both groups. This was in agreement with other studies[1112151619202122] [Table 5]. Even though we did not perform these procedures as outpatient procedures but with well defined, well set protocols, in our view, these can be performed as day-care procedures.

Cosmesis has been one of the reasons for easy acceptance of laparoscopic surgery among the patient population. Smaller and lesser incisions have led to minimal scarring and improved cosmesis.[1723] But non-existence of a uniform scale to evaluate cosmesis severely hampers direct comparison between various studies. We used a scale of 0-10 to assess cosmesis as done in most studies, with 0 being worst and 10 being the best. In our study, we had a nurse blinded to procedures and the patient's own score which minimised bias. The final score was arrived at by calculating the mean of the two scores. In our study, the cosmetic score was significantly better in two port mini LC, which is similar to other studies where cosmetic benefit was studied.

In our conclusion, LC can be performed with two-port technique using 10-mm umbilical, 5-mm epigastric and two 2.3-mm graspers in properly selected cases and optimise the benefits of minimal access surgeries.