The Laparoscopic Approach for Perforated Appendicitis,Including Cases Complicated by Abscess Formation

Introduction

In comparison with open surgery, the laparoscopic approach for appendicitis has better clinical outcomes, such as reduced use of analgesics, shorter hospital stay, faster return to daily activities, and lower rate of wound infection.^1,2 Although some studies have reported no significant benefit and higher surgical costs with regard to this approach,^3–6 laparoscopic treatment for appendicitis is generally accepted as a safe, effective procedure.^7–9 On the other hand, the laparoscopic approach for perforated appendicitis is controversial, especially with regard to the rate of postoperative complications, such as intra-abdominal abscesses.^10–12 This is because perforated appendicitis includes various disease entities, from gangrenous change to diffuse peritonitis with abscess formation. In fact, perforated appendicitis complicated with abscess is not easy to manage and may result in complications. To elucidate the safety and the effectiveness of the laparoscopic approach, we classified patients into two subgroups: 1) perforated appendicitis without abscess and 2) perforated appendicitis complicated by an abscess. The aim of this study was to compare the safety and benefits of laparoscopy versus open surgery for the treatment of perforated appendicitis, including cases complicated by abscess formation.

Materials and Methods

Over a period of 3 years (from 2006 to 2008), 1747 patients underwent treatment for appendicitis. The diagnosis of perforated appendicitis with or without complicated abscess was made on the basis of radiologic, operative, and pathologic findings. Preoperative radiologic diagnoses was suspected perforated appendicitis including localized or generalized peritonitis, periappendiceal fat infiltration with phlegmon, adjacent bowel-wall thickening, and/or abscess formation. Abscesses were identified by pus drainage from the cavity during surgery. Abscesses confirmed by pathologic examination were also included in the perforated appendicitis with abscess group.

Of the patients with perforated appendicitis complicated by abscess, 7 who underwent initial percutaneous drainage and intravenous (i.v.) antibiotics and 12 who underwent ileocolic resection for dense bowel adhesion or suspected obstruction were excluded. The operative method was determined by the attending surgeons who first examined the patients in the emergency room as duty schedule or in the outpatient clinic. Of our five attending surgeons, three performed open surgery for perforated appendicitis, whereas two performed laparoscopy. Under general anesthesia, open surgery was performed through a Rocky-Davis or McBurney incision. Dissection, vessel ligation, and irrigation were performed by conventional methods. A purse-string suture was used for appendiceal stump closure, and pus drainage was performed by incision and suction.

The laparoscopic approach was performed with the three-trocar approach (two 5-mm, one 11-mm), using monopolar dissectors and forceps. Pretied suture loops were used for stump closure, and pus drainage was performed by using Surgiwand (Covidien, Mansfield, MA). The Endo-GIA™ (Covidien) stapling device was used for 5 patients with a friable stump. A tube drain was used in cases where dissection was difficult for treating adhesion, generalized peritonitis, or confirmed abscesses.

Patients were treated with bowel rest until flatus passage. Antibiotic treatment was begun immediately at admission until the patient was afebrile and the white blood cell count returned to normal. The patients were followed up at least once after discharge. We compared the clinical outcomes, including operating time, resumption of diet, length of hospital stay, and rate of postoperative complications, between the subgroups of the laparoscopy and open surgery groups (i.e., without and with abscess). The chi-square and the t-test were used, and a P-value of less than 0.05 was considered statistically significant.

Results

All patients were older than 15 years and underwent appendectomy with or without drainage. Data indicated that 474 patients (27%) had perforated appendicitis without abscess and 113 patients (6.4%) had perforated appendicitis with abscess. Among 474 patients without abscess (mean age, 36.6 ± 13.5 years; 256 men and 218 women), 156 underwent laparoscopy and 318 patients underwent open surgery. There were 3 (2%) conversions in 156 patients after laparoscopy: 2 for a dense adhesion and 1 for a crushed appendiceal stump. There were no mortalities and fecal diversions.

The age, gender, and white blood cell count at admission of the patients in both groups were comparable. Operating time for the laparoscopy was longer than that for open surgery. The duration of resumption of diet and hospital stay in the laparoscopy group was considerably shorter than that in the open surgery group. There was no significant difference in the rate of complications between the two groups (Table 1).

Of the 156 patients in the laparoscopy group, postoperative intra-abdominal abscesses developed in 5. Four patients were managed by antibiotics alone and 1 by percutaneous drainage. There were 10 patients with wound infections, and they were managed by using supportive care, such as wound drainage or frequent wound dressing. Of the 318 patients in the open surgery group, 11 patients had postoperative intra-abdominal abscesses: 7 patients were managed by antibiotics alone and 4 by percutaneous drainage. There were 25 cases of wound infections. One patient with open surgery underwent adhesiolysis for an obstruction 2 months after treatment; the small bowel had adhered to the retroperitoneum, resulting in obstruction (Table 2). Among the 113 patients with abscesses (mean age, 44.8 ± 16.2 years; 66 men and 47 women), 44 underwent the laparoscopy approach and 69 had open surgery. All converted cases were included in the laparoscopic group. There were no incidences of mortality or fecal diversion.

There were no statistical differences with regard to the operating time or rate of postoperative complications between the laparoscopy and open surgery groups. The duration for resumption of diet and hospital stay in the laparoscopy group was also shorter than that in open surgery group (Table 3). Of the 44 patients in the laparoscopy group, there were 4 (8%) conversions after laparoscopy: 2 for a dense adhesion and 2 for a crushed appendiceal stump. Postoperative intra-abdominal abscesses developed in 4 (8%) patients: 3 patients were managed by antibiotics alone and 1 by percutaneous drainage. There were 3 cases with wound infections. There were no complications in converted patients. Of the 69 patients with open surgery, 6 patients (8%) had postoperative intra-abdominal abscesses: 3 patients were managed by antibiotics alone, 2 by percutaneous drainage and 1 by ileocolic resection for internal fistula. There were 6 cases of wound infections (Table 4). Of all the enrolled patients, prolonged postoperative ileus developed in 15 patients, all of whom were treated successfully with bowel rest.

Discussion

Although there may not be contraindications for the use of laparoscopic appendectomy for perforated appendicitis, there is controversy about the efficacy of laparoscopy in cases complicated by intra-abdominal abscess formation, when compared to open surgery. Many studies have shown that laparoscopic appendectomy is safe for treating complicated appendicitis and have recommended that it be used for the same.^13–18 However, in most studies, the assessment of laparoscopic treatment was carried out in appendicitis patients with various types of complications, and, therefore, the role of laparoscopy was not accurately determined. Moreover, some studies included children.

Therefore, we only enrolled patients who were older than 15 years, and we classified perforated appendicitis into two subgroups: with and without abscess. In the present study, the prevalence of perforated appendicitis with abscess was 6%, while perforated appendicitis without abscess occurred in 27% of patients. Most of the patients with perforated appendicitis without abscess were effectively treated by appendectomy with or without drainage. Among the total of 474 patients, 16 (3.4%) had intra-abdominal abscess and 35 (7.4%) had wound infection. The rate of postoperative intra-abdominal abscess formation was similar in both groups. Most of the abscesses occurred at the appendectomy site or in the retrocecal area. These findings suggest that remnant inflammation, bowel injury during dissection, or stump leakage may be related to the presence of a postoperative intra-abdominal abscess.

There is controversy over the operating time of laparoscopy and open surgery for perforated appendicitis. This study showed that the operating time in the laparoscopy group was 6 minutes longer than that in the open surgery group for perforated appendicitis without abscess; however, there was no difference in the operating time in cases of perforated appendicitis with abscess. In our initial experience, the operating time for laparoscopy was about 15 minutes longer than that for open surgery. However, owing to increasing experience in laparoscopy, the difference in the operating time for the two procedures is not significant.

On the other hand, it is likely that the operating time for perforated appendicitis with abscess was steady, not taking into consideration experience and operative methods. Surgical procedure for abscess is technically difficult and risky. In addition, the decision of whether to perform a simple appendectomy or to follow a different treatment strategy was not easy to make. Goh et al. reported that patients who had undergone treatment for an appendiceal mass had significantly longer operating time than patients without a mass. ¹⁹

Twelve patients who had undergone ileocolic resection for an abscess were excluded from this study. These patients exhibited severe inflammation of the adjacent bowel wall and mesentery, leading to an obstruction. The mean operating time in patients who underwent ileocolic resection was 163 minutes. One patient with an open ileocolic resection underwent small bowel resection for obstruction 16 months after treatment. There were no complications among the other patients who underwent ileocolic resection. Although those who undergo ileocolic resection require a long hospital stay (mean, 10 days), this procedure is not necessarily associated with a high complication rate.

The use of initial percutaneous drainage for perforated appendicitis with abscess, followed by interval appendectomy, is an effective alternative approach. However, this procedure is not always technically feasible and may lead to additional morbidity due to treatment failure and disease aggravation. Moreover, management of the disease has recurrence risks and requires considerable resources. A recent review of the nonoperative management of appendiceal abscesses revealed that the incidence of failure for the initial treatment was 7.2% and the risk of recurrence was 7.4%. ²⁰ We had 7 patients with abscess that could be initially managed by percutaneous drainage and antibiotics, and, of these, 2 patients underwent subsequent treatment for a recurrent abscess.

One of the problems is that differential diagnosis of a periappendiceal mass is still not easy from unexpected disease, including diverticulitis, malignancy, and inflammatory bowel disease. The subsequent incidence of other pathologic diseases is reported to be approximately 10%, particularly among the patients that present with an initial periappendiceal mass.^21,22 In the same period, we had 19 cases where unexpected pathologies were observed for the periappendiceal mass: 9 with right colonic diverticulitis, 3 with mucinous cystadenoma, 3 with Crohn's disease, 2 with malignant lymphoma, 1 with intestinal tuberculosis, and 1 with adenocarcinoma. Therefore, early surgical treatment appears to be an alternative to medical treatment and should be compared with nonoperative treatment in a prospective trial.^23,24

The present study suggests that the laparoscopic approach for perforated appendicitis has diagnostic, as well as therapeutic, value even in cases complicated with abscess formation, and, further, may be comparable to open surgery with regard to the incidence of complications. The accurate diagnosis of disease status under laparoscopic visualization may be evaluated, particularly in cases of suspected perforated appendicitis. In many patients, the base of the appendix was accessible and appendectomy with drainage was appropriate. Katsuno et al. demonstrated that accumulating experience with more sophisticated laparoscopic techniques may lead to shortening of operating time and a decrease in rate of complications. ²⁵ This finding would lead to an increase in the use of the laparoscopic approach for perforated appendicitis. The laparoscopic approach may be feasible for the examination of the whole peritoneal cavity, and it plays an important role in the accurate diagnosis of disease state and in treatment selection for perforated appendicitis with abscess. Moreover, by using this approach, lengthy skin incisions were avoided, which were not favored by patients who underwent open surgery.

Conclusions

In conclusion, most cases of perforated appendicitis can be managed by appendectomy with or without drainage. In addition, this study showed that the laparoscopic approach for perforated appendicitis, including cases complicated by abscess formation, was comparable to open surgery.