hospital stay, number of interventions, healthcare costs, and overall patient satisfaction must be

considered.

Figure 71-2. Perforated appendicitis.

Appendiceal Abscess

Appendiceal abscess is commonly associated with delayed presentation, fever, leukocytosis, and a

palpable mass in the right lower quadrant (Fig. 71-2). The diagnosis is confirmed with CT or US.

Management of these patients remains controversial. The traditional nonsurgical approach consists of

percutaneous drainage and IV antibiotics, with or without interval appendectomy. Others suggest

immediate appendectomy and surgical drainage of the abscess. The evidence supporting both

approaches is weak, as most studies are retrospective and often combine patients with appendiceal

abscess and phlegmon into a single cohort called “appendiceal mass.” Several meta-analyses have been

performed to try to identify differences between the two treatment strategies. Andersson and Petzold

performed a meta-analysis on 19 retrospective studies from 1969 to 2005. The limitation of this study is

the lack of uniform definition of appendiceal abscess and phlegmon. Nevertheless, the meta-analysis

revealed that nonsurgical treatment failed in 7.6% of patients (CI: 3.2 to 12.0). Immediate

appendectomy is associated with a higher morbidity with an OR of 3.3 (CI: 1.9 to 5.6). Based on these

findings, the authors recommended nonsurgical management of patients with appendiceal abscess.53

Similar conclusions were reached by Simillis and colleagues, who performed a meta-analysis of 16

retrospective studies and 1 nonrandomized prospective study from 1969 to 2007, comparing immediate

appendectomy (725 patients) versus nonsurgical treatment (847 patients).57 Immediate appendectomy

is associated with greater incidence of ileus or bowel obstruction, abdominal or pelvic abscess, and

wound infection compared to nonsurgical treatment. There was no difference in the overall duration of

hospitalization, but the immediate appendectomy group required more reoperations. The higher rate of

complications associated with immediate appendectomy has been attributed to greater inflammatory

response to surgery in the setting of infection, as well as the technical difficulty with inflamed tissue.

Most of the studies analyzed in these meta-analyses utilized open appendectomy techniques. The

potential disadvantages of early operation may be mitigated by the laparoscopic techniques.

Laparoscopic appendectomy results in less local inflammation due to better visualization and

instrumentation.58

St. Peter and colleagues conducted a prospective randomized trial comparing immediate laparoscopic

appendectomy to nonsurgical treatment in 40 pediatric patients presenting with appendiceal abscess.59

Immediate laparoscopic appendectomy tends toward longer operative time (61 minutes vs. 42 minutes)

compared with interval laparoscopic appendectomy performed at 10 weeks from initial presentation.

The immediate appendectomy group had fewer healthcare visits and few CT scans. However, there was

no difference in recurrent abscess rate, total length of hospitalization, or total charges. They concluded

that immediate laparoscopic appendectomy is as safe as nonsurgical management. The safety of

immediate laparoscopic appendectomy for appendiceal abscess is supported by several other

retrospective or uncontrolled studies.60–63 The infectious complications of immediate appendectomy can

be reduced by improved laparoscopic techniques, such as use of extraction bag, endostaplers rather than

endoloops, and limited irrigation to avoid bacterial contamination.64,65

Appendiceal Phlegmon

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The management of acute appendicitis complicated by an appendiceal phlegmon typically involves 1 of

3 treatment strategies (Fig. 71-3). The first, and most commonly accepted, is initial treatment with

broad spectrum antibiotics and IV fluids until the acute inflammation subsides; appendectomy is then

performed on an interval basis. Another strategy involves appendectomy upon initial presentation.

Finally, following resolution of the acute inflammation with broad spectrum antibiotics, the patient is

managed expectantly without interval appendectomy. Prospective data comparing these strategies are

sparse, with most systematic reviews drawing heavily upon retrospective data.

At present, there is no agreed upon approach for the management of an appendiceal phlegmon. A

recently published survey of a group of general surgeons in England found that 75% still favor interval

appendectomy following resolution of symptoms.66 Proponents for interval appendectomy state that

removing the appendix is a technically easier operation once the acute inflammation subsides,

potentially avoiding inadvertent injury to adjacent loops of involved bowel, as well as extended

resection of the cecum or ascending colon.56 Although the risk of recurrent appendicitis remains small

after successful nonoperative treatment of an appendiceal phlegmon, proponents of interval

appendectomy state that the risk of interval appendectomy is also small and eliminates the possibility of

recurrent appendicitis.54 In a recent systematic review published by Hall and colleagues, 127 children

were managed without planned interval appendectomy.67 The incidence of recurrent appendicitis

ranged from 0% to 42% in the three studies included in the review, with an overall risk of 20.5% (95%

CI: 14.3 to 28.4).

Figure 71-3. Perforated appendicitis with associated abscess.

The complication rates following interval appendectomy were also published in this review, with an

overall incidence of 3.4% (95% CI: 2.2 to 5.1). The authors concluded that the likelihood of recurrent

appendicitis, as well as the risk of complication after interval appendectomy, are both sufficiently low

that the decision to proceed with interval appendectomy is typically based on clinical criteria.

Interval Appendectomy

Interval appendectomy provides a tissue diagnosis when diagnostic uncertainty exists. This is

particularly important in adults because the differential diagnosis of an inflammatory mass in the right

lower quadrant can be quite extensive, with neoplastic etiologies of particular concern. In a systematic

review and meta-analysis, 2,771 included patients were initially treated nonoperatively for an

appendiceal phlegmon or abscess.53 On follow-up, 31 patients were found to have a malignant

diagnosis. In patients younger than 40 years with an appendiceal mass, only 4 were found to have a

malignant diagnosis on follow-up: 2 children had carcinoid of the appendix, a 26-year-old woman

presented with an ovarian malignancy, and a 25–year-old man presented with metastatic gastric cancer.

The overall estimate of a malignant diagnosis was 1.2% (95% CI: 0.6% to 1.7%), with an incidence of

0.2% (95% CI: 0.0% to 0.05%) in children. Inflammatory bowel disease was established as a diagnosis

during follow-up in 0.7% of patients (95% CI: 0.2% to 11.9%), with a higher incidence again seen in

adults. Although primarily retrospective, these data underscore the need for follow-up, either with CT

scan or colonoscopy, after successful treatment of an appendiceal phlegmon in adults.53

The presence of an appendicolith associated with an appendiceal phlegmon deserves special mention,

as its presence has been used as a guide to proceed with interval appendectomy following successful

nonoperative management. A retrospective cohort study reviewed the outcomes of 96 pediatric patients

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with appendicitis who presented with either an inflammatory mass or phlegmon, and were initially

managed nonoperatively by the staff surgeon.68 Six patients who failed initial nonoperative

management underwent appendectomy and were excluded. Forty-one patients were scheduled for

elective appendectomy by their surgeon and were also excluded from analysis. The remaining patients

were included in the study and their outcomes over a 2-year period were reported. Of these, 37% had

an appendicolith and 63% did not. The overall recurrence rate for appendicitis was 42%; in patients

with an appendicolith, the recurrence rate was 72% compared to 26% in patients without an

appendicolith (relative risk of 2.8 in patients with an appendicolith). The authors concluded that the

presence of an appendicolith predicts failure of nonoperative management of periappendiceal phlegmon

or abscess. It is important to note that the overall recurrence rate of appendicitis in this study is higher

than what is typically reported elsewhere in the literature, and this may influence the true effect of an

appendicolith on failure of nonoperative management.

Unfortunately, there are no data from a randomized, prospective trial evaluating whether or not the

presence of an appendicolith is predictive of failure of initial nonoperative management of ruptured

appendicitis with phlegmon or abscess. As such, any conclusions from this study should be viewed as

hypothesis-generating for a future randomized controlled trial.

In deciding whether or not to proceed with routine interval appendectomy following successful

nonoperative management of an appendiceal phlegmon or abscess, the effect of cost must also be

considered.69 Even with a high probability of recurrent appendicitis (assumed to be 40%), financial

analysis does not favor elective interval appendectomy.

A more robust randomized trial looking at the return to normal activity examined 131 total patients

enrolled: 64 receiving initial appendectomy, and 67 were assigned to interval appendectomy.70 In the

primary appendectomy group, time to normal activity was 13.8 versus 19.4 days in the interval

appendectomy group (P < 0.001). Of note, the relative risk of any adverse event associated with

interval appendectomy was 1.86; specific outcomes measured included intra-abdominal abscess, smallbowel obstruction, unplanned readmission, and recurrent appendicitis, and these were all seen with

higher frequency in the interval appendectomy group. The authors conclude that early appendectomy

significantly reduced the time away from normal activity and showed a significantly lower adverse

event rate.

5 The optimal management strategy of an appendiceal phlegmon or abscess remains elusive as most

recommendations are based on retrospective data, but recent randomized trials in children indicate that

early appendectomy results in faster return to normal activity with favorable complication rates when

compared to interval appendectomy.70 Performing an interval appendectomy following successful

nonoperative management with antibiotics and percutaneous drainage, as needed, has yet to be

evaluated in a randomized trial. Higher-quality evidence from prospective, randomized trials will help

surgeons decide whether or not interval appendectomy in the setting of an appendicolith is appropriate.

SURGICAL OPTIONS FOR ACUTE APPENDICITIS

Laparoscopic versus Open Appendectomy

The open appendectomy was initially described by McBurney in 1894, and has remained relatively

unchanged since its introduction. In 1983, Semm described a laparoscopic approach for removing the

appendix, advocating the advantages of laparoscopic surgery for one of the most frequently performed

surgical procedures.71 Since open appendectomy also typically involves a small incision, short hospital

stay, rapid return to normal activity, and low postoperative morbidity, demonstrating clear superiority

of one approach over the other has been elusive. Although many randomized control trials comparing

open versus laparoscopic appendectomy have been performed, many contain methodologic flaws,

including inadequate allocation concealment, lack of reporting of randomization method, failure of

adequate blinding, lack of analysis by intention-to-treat, and incomplete follow-up data.72 That being

said, these randomized trials, as well as systematic reviews and meta-analyses of these studies, have

provided a great deal of insight into the specific benefits and drawbacks of each approach. In deciding

between a laparoscopic and open approach, specific issues that must be considered include learning

curve, operative time, associated morbidity, cost, pain, cosmesis, hospital length of stay, and time to

return to normal activity. Unfortunately, measures vary across studies and conclusions have been

inconsistent.

A large retrospective review of prospectively acquired data, compared outcomes of laparoscopic

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