Laparoscopic vs Transumbilical Single-Port Laparoscopic Appendectomy; Results of Prospective Randomized Trial

Appendicitis is the most common intra-abdominal condition requiring emergency surgery and carries a lifetime risk of 6%.(1, 2) For more than a century, open appendectomy remained the gold standard for the treatment of acute appendicitis.

Semm(3) described the first endoscopic appendectomy in early 1983. Laparoscopic surgery has become popular in developed countries during the last decade primarily because it is associated with improved cosmetic results, shorter hospital stays, less postoperative pain, and earlier return to work. However, despite these advantages, efforts are still being made to decrease abdominal incision and visible scars after laparoscopy. The use of technology to accomplish "scarless" surgery may eventually give rise to a new paradigm of disease management-based patient care. Recent research has led to the development of natural orifice translumenal endoscopic surgery (NOTES). However, there are numerous difficulties that need to be overcome before the wider clinical application of NOTES is adopted, including complications such as the opening of hollow viscera with associated risk of peritonitis, failed sutures, and pneumoperitoneum; a lack of fully developed instrumentation; and the necessity of reliable cost-benefit analyses.(4-7)

Transumbilical single port laparoscopic surgery is virtually scarless as the intra-abdominal entry point is hidden in the umbilicus. This procedure is becoming a common alternative form of minimally invasive surgery. Since 1992, after the initial performance of a single-trocar appendectomy,(8) various studies evaluating transumbilical single-port laparoscopic appendectomies (TUSPLA) have been conducted.(9-12) However, until recently TUSPLA has been less popular in clinical practice than traditional laparoscopic appendectomy (LA). The goal of our study was to conduct a comparative analysis of the clinical outcomes for LA and TUSPLA.

The two patient groups included in this study did not differ in terms of age, sex, initial WBC, or initial CRP (Table 1). The operating time was shorter for the LA patients (54.0±12.5 min) than the TUSPLA patients (63.5±13.2 min). However, this difference was not statistically significant. Postoperative day 3 WBC and CRP levels, time until gas out, diet, and length of postoperative hospital stay were similar in both study groups. Patients in the two groups were equally satisfied with their cosmetic results (P=0.759)(Table 2). The TUSPLA group reported a significantly higher average VAS score than the LA group (P<0.05) during the first 24 postoperative hours (Fig. 2). There were no differences in the amounts of IV pain control that were used during hospitalization (P=0.543).

Fig. 2
Visual analog pain scores during first 48 postoperative hours after operation

• Click for larger image

Table 1
Clinicopathologic characteristics of patients

• Click for larger image

Table 2
Postoperative clinical data for LA and TUSPLA

• Click for larger image

Complications occurred in four patients. In the LA group, one patient had a wound infection, and another had paralytic ileus. In the TUSPLA group, one patient had a wound infection, and another had an intra-abdominal abscess (Table 3). The patient who had ileus in the LA group resolved after three days fasting and was discharged from the hospital. The patient who had the intra-abdominal abscess in the TUSPLA group was diagnosed in the outpatient clinic on postoperative day 7 and admitted. The abscess resolved after seven days of antibiotic therapy, and the patient was then discharged from the hospital. One patient in the TUSPLA group was found to have a perforated appendix during surgery. A 5 mm trocar was added to the supra-pubic lesion and a drain was inserted.

Table 3
Postoperative complications

• Click for larger image

Minimally invasive surgery is becoming very popular. In 2004, Kalloo et al.(13) published a study on the endoscopic scanning of the internal abdominal cavity after an abdominal wall incision. Since then, various studies on NOTES have been conducted. NOTES is a new operative technology that does not involve a skin incision. Clinical trials have been conducted on small end organ procedures including appendectomies, cholecystectomies, as well as on large organs such as the colon.(13-19) However, clinical trials involving NOTES have not been conducted frequently on human subjects. There are many obstacles that need to be overcome before NOTES is widely performed.(4-7)

TUSPLA has the advantage of requiring only a single incision in the umbilicus, making it virtually scarless. It is easily compared to NOTES, and is thus becoming more popular. The TUSPLA technique using a wound retractor and glove that was originally presented by Hong et al.(20) may be performed with conventional instruments without extra cost. Our hospital has been performing TUSPLA since 2009.

Our study was conducted safely and showed no differences in clinical outcomes between patients treated by TUSPLA and LA. These results are similar to those of previous studies.(11, 20) If necessary, a surgeon can easily convert a TUSPLA procedure to a LA by adding another trocar. This allows the safety of the patient to be preserved.

The TUSPLA group in our study suffered from several disadvantages. A previous study found no differences in the VAS measurements between patients treated by LA and TUSPLA one day after the operation.(11) However, that study did not conduct successive postoperative VAS measurements. In the results of the present study, serial examination of post-operative pain intensity by VAS documented significantly higher levels of pain in TUSPLA patients 24 hours after surgery. This may have been caused by the length of the fascial incision, which is longer than that of umbilical incision used in a TULA, and the wound irritation seemed to be greater when the surgical instrument had to be inserted through only single incision. The bladeless trocars that are currently being used for TUSPLA minimize injury to the abdominal wall tissue. This could be a factor which leads to differences in reported pain between the two groups.(21-23)

As previously mentioned, the external instrument clashing and limitation of motion that is caused by the parallel and close proximity of the instruments that must operate through one small hole are problems that could be solved by instrument development.(11, 20, 24, 25)

There were some limitations to this study. The average age of the LA and TUSPLA group was younger, and the number of female patients was higher compared to that of the entire population that was diagnosed with appendicitis during the same period (26.1 vs. 32.0, 57.5% vs. 43%). This reflects the fact that patients who preferred laparoscopic operations and young female patients who were sensitive to scarring, were more likely to be enrolled in the study.

Based on the preoperative evaluations, those patients who were suspected of having complicated appendicitis, such as an abscess or perforation, were exempted from the study. To overcome this limitation, a study with a larger sample of patients with appendicitis included abscess and perforation should be carried out.

TUSPLA is a "scarless" operation. The questionnaire administered during this study revealed no differences in satisfaction with scarring between the two groups (P=0.759). The TUSPLA patients did not have the chance to compare their scars with those created by different operation methods. Consequently, a different method of conducting the satisfaction survey is required for more objectivity.

In conclusion, Compared to LA, TUSPLA was technically feasible and safe in patients with non-complicated appendicitis. Considering the risks and benefits of TUSPLA that were discussed in this study, more careful patient selection is necessary. Further prospective studies comparing TUSPLA and LA in a large number of patients, especially for pain evaluation, including those with complicated appendicitis, are required to confirm the current promising results.