Clipless Versus Conventional Laparoscopic Cholecystectomy

Introduction

The surgical removal of the gallbladder, or cholecystectomy, is one of the more commonly performed procedures by general surgeons. Cholecystectomy represents the most common biliary tract procedure and the second most common surgical procedure overall. ¹ Traditionally, the open procedure was performed through a right subcostal incision, or a Kocher incision. The Kocher incision was named after Theodor Kocher, the surgeon who performed the first successful cholecystectomy in 1878. ¹ For over 100 years, the procedure was performed open. However, in 1988, the first laparoscopic cholecystectomy was performed in humans. ² Laparoscopic cholecystectomy has become the gold standard and preferred technique for the procedure. ³ Numerous studies have compared the laparoscopic and open procedures. The former has proven advantageous in decreased complication rates, shorter hospital stays, and shorter duration of surgery, as well as compared favorably in cost-effectiveness for both the patient and the hospital.^3,4 Although the advent of laparoscopic cholecystectomy has been revolutionary, it has created a new set of complications surgeons wish to prevent such as liver bed injury, spilled gallstones, vascular injury, potential for conversion to open surgery, umbilical port hernia, port-site infection, bowel injury, and biliary leak. ⁵ Although laparoscopic surgery has proven to a relatively safe procedure, modern technology has afforded the opportunity to develop improved techniques to decrease potential complications, decrease costs, and improve efficiency. One of the more recent trends in laparoscopic research has focused on vessel sealing instruments that utilize alternative energy sources. ⁶ In laparoscopic cholecystectomy, there is a potential for benefit with these new instruments in exposure, dissection, and occlusion of the cystic duct and artery. Currently, the placement of surgical clips is the most commonly used technique of cystic duct occlusion. ³ Clips, however, have the potential to result in complications such as a bile leak of the cystic duct stump. This can be due to a displaced clip, to necrosis of the cystic dump stump due to an incorrectly placed clip initially followed by a second clip distally, or to a clip placed too proximal to the common bile duct causing entrapment or injury. ⁷ Additionally, displaced clips can migrate into adjacent structures. They can cause stricture formation due to a foreign body response if the clip is displaced or is dropped during insertion. ⁸ Therefore, the use of a single instrument for exposure, dissection, and occlusion of both the cystic duct and artery would decrease these potential complications associated with clip placement and increase efficiency in the operating room.

Several alternative energy sources have been used in laparoscopic cholecystectomy for cystic duct occlusion with varying success. Early studies focused on the use of ultrasonic coagulating shears and electrothermal bipolar vessel sealers. A study by Matthews et al. ⁹ compared the two instruments versus surgical clips and found a significant difference in ex vivo cystic duct bursting pressures, and both alternative instruments had a high rate of failure in the in vivo pig studies. Another study comparing electrothermal bipolar vessel sealing devices and ultrasonic coagulation shears demonstrated similar high rates of failure in ex vivo cystic duct bursting pressures in pigs. ¹⁰ However, more recent studies have found increased success. A study by Jain et al. ¹¹ found the ultrasonically activated scalpel as a safe alternative to clips and proved better than electrocautery. Yet another compared the Harmonic^® scalpel (Ethicon Endo-Surgery, Cincinnati, OH) and PlasmaKinetic sealer (Gyrus, Minneapolis, MN) with surgical clips. The study by Kavlakoglu et al. ¹² found that the Harmonic scalpel was more effective than the PlasmaKinetic sealer and equally safe and effective as surgical clips.

This study aims to compare the use of the Harmonic scalpel versus surgical clip placement for cystic duct occlusion in laparoscopic cholecystectomy.

Subjects and Methods

Data were retrospectively compiled from 208 patients undergoing laparoscopic cholecystectomy for both inpatient and elective surgery during the time period of May 4, 2011–June 13, 2012 (Table 1). The patients underwent laparoscopic cholecystectomy in which exposure and dissection were performed using the Harmonic scalpel. Patients were chosen randomly at the discretion of the surgeon to receive a single surgical clip or use of the Harmonic scalpel for cystic duct occlusion if the cystic duct measured less than 5 mm. An Endo GIA™ stapler (Covidien, Mansfield, MA) was used for cystic duct occlusion in patients with cystic ducts greater than 5 mm. The size of the cystic duct was determined by the judgment of the surgeon. If surgical clips were used, the Harmonic scalpel was additionally used to cut the cystic duct. Ex vivo gallbladders were tested for failure of cystic duct closure by manually examining bursting pressure. If the cystic duct was deemed to be ineffective with the Harmonic scalpel, then conversion to use of a surgical clip was done for increased patient safety. Retrospectively, patient data were assessed for any postoperative complications upon outpatient follow-up to the clinic or requiring re-admission. Specifically, bile leak was the most important complication assessed and documented. Postoperative complications seen on outpatient follow-up were most commonly nausea, vomiting, and nonspecific abdominal pain.

Results

The following results were compiled listing the number of postoperative complications and subsequently broken down by those discovered by outpatient follow-up and those requiring re-admission. Bile leak was specifically noted. The percentage of total postoperative complications, outpatient complications, patients requiring re-admission, and those with bile leak were calculated for both the surgical clip group and the Harmonic scalpel group (Table 2).

There was a total postoperative complication rate of 9.62%, and the overwhelming majority of postoperative complications were found during outpatient follow-up. All patients who were not subject to re-admission required no further treatment and reported no complications upon further follow-up. The most common postoperative complication was nausea (n=9), followed by nonspecific abdominal pain/mild abdominal pain (n=6), vomiting (n=3), diarrhea (n=2), and one case of rib swelling that was deemed benign. Surgical clip and the Harmonic scalpel produced similar results as far as outpatient follow-up with rates of 5.96% and 7.02%, respectively. However, the two techniques have a larger difference for re-admission rates, with 0.66% for surgical clip and 10.53% for the Harmonic scalpel. The single re-admission for the surgical clip was a bile leak due to a cystic duct leak and subsequent biloma formation. The reason for re-admission varied for the Harmonic scalpel and was not necessarily dependent on the technique used. Three of the 6 cases were due to a bile leak, which will be discussed in further detail with the bile leak rates. The other 3 were due to causes other than a bile leak and likely independent of the cystic duct occlusion technique used in the procedure. One patient was re-admitted because of nonspecific abdominal pain. Another patient was re-admitted from the emergency room because of nausea and oral intake intolerance; this patient was diagnosed with post-cholecystectomy syndrome and was found to have a pancreatic pseudocyst. The last patient was admitted because of persistent nausea, which was the inciting symptom for surgery but was not relieved by cholecystectomy. For the complication of bile leak, the surgical clip had a rate of 0.66%, whereas the Harmonic scalpel was found to have a rate of 5.26%. However, not all of the bile leaks associated with the Harmonic scalpel were due to failure of cystic duct occlusion. One patient was confirmed to have a cystic duct leak, and the other 2 cases were due to leak at a different location in the biliary tree. One patient had a common bile duct injury, and the other had a posterior accessory duct that was not visualized during surgery. Both of the latter cases were bile leaks due to causes irrespective of cystic duct occlusion technique. Of note is that 3 patients were converted to surgical clips after failure of manual testing of the cystic duct seal after Harmonic scalpel use and were included in the surgical clip statistics. All three conversions were without any postoperative complications. Another patient was determined to have a cystic duct leak intraoperatively, which was corrected before the procedure was ended.

A two-sample t test was used to determine the statistical significance of the outpatient follow-up complication rates, re-admission rates, and bile leak rates between the use of surgical clips and the Harmonic scalpel. The two-sample t test demonstrated no significant statistical difference between the surgical clip versus the Harmonic scalpel when comparing outpatient follow-up complication rates (P=.7785). However, there was a significant difference between surgical clips and the Harmonic scalpel when comparing re-admission rates and bile leak rates (P=.0005 and P=.0322, respectively). Alternatively, if we adjust the re-admission and bile leak rates by excluding the cases that were irrespective of cystic duct occlusion technique, then the rates for the Harmonic scalpel become 5.26% and 1.75%, respectively. These cases can be excluded because of the fact that the Harmonic scalpel was used for dissection and exposure of the cystic duct in both techniques of cystic duct occlusion. Using the adjusted rates, the comparison of re-admission rates maintained a statistical significance (P=.0322), whereas the adjusted bile leak rates demonstrated no statistical difference (P=.4726).

Discussion

Although postoperative complications noted at outpatient follow-up were comparable, the initial look at the raw data seems to support the use of surgical clips over use of the Harmonic scalpel for cystic duct occlusion in laparoscopic cholecystectomy. Both the rates of re-admission and bile leak were statistically significant in favor of surgical clips versus the Harmonic scalpel. However, with the exclusion of bile leaks that did not involve the cystic duct, the rates of bile leak were comparable between surgical clips and the Harmonic scalpel (0.66% and 1.75%, respectively), demonstrating no statistical difference between the two techniques. On the other hand, re-admission rates maintained a statistical difference despite exclusion criteria. Despite the discrepancy in re-admission rates, the Harmonic scalpel appears to be a safe and comparable method of cystic duct occlusion. Because of the potential for long-term complications of stricture formation, necrosis, and displacement with surgical clips, the Harmonic scalpel may in fact be a more superior technique. The use of a single instrument for the exposure, dissection, and occlusion of both the cystic duct and artery increases efficiency in the operating room, decreases operation time, and undoubtedly decreases cost because another instrument does not need to be opened for the case. Further research into the costs of using the Harmonic scalpel versus surgical clips needs to be explored more thoroughly. Additionally, larger homogeneous studies in which an equal number of patients receive surgical clips and use of the Harmonic scalpel could more definitively determine if the Harmonic scalpel is potentially safer at preventing complications and decreasing incidence of postoperative bile leaks. Furthermore, the method of manually testing the cystic duct ex vivo appears to be an effective method to insure that a bile leak does not occur because of use of the Harmonic scalpel alone. Overall, use of the Harmonic scalpel at the discretion of the surgeon is an effective choice for cystic duct occlusion.