The Incidence of Intraabdominal Abscess Formation Following Laparoscopic Appendicectomy in Children: A Systematic Review and Meta-analysis

Is transumbilical laparoscopic-assisted appendectomy feasible for complicated appendicitis? A single-center experience

PURPOSE

Transumbilical laparoscopic-assisted surgery (TULS) mixed benefits of laparoscopic and open surgeries. Transumbilical laparoscopic-assisted appendectomy (TULAA) is a well-known procedure, accepted and currently used by pediatric surgeons for treatment of uncomplicated appendicitis (UA). There is no current agreement in its use for the complicated appendiceal infections (CA). We reported our results using TULAA for both UA and CA.

METHODS

We retrospectively collected TULAA performed between April 2017 and April 2022. Appendicitis were classified in UA and CA. We analyzed conversion rate, operative time, length of stay, surgical site infections (SSIs) rate, postoperative intra-abdominal abscess and costs.

RESULTS

Over 5 years, 316 children underwent TULAA. Conversion rate was 3%. Mean age at surgery was 9.36 years (IQR 2-16). Forty-nine appendicitis were CA. Operative time and hospital stay was higher in CA than in UA group (38.33 vs. 60.73 min, p < 0.00001; 4 vs. 7 days, p < 0.00001). SSIs rate showed no statistically significant difference between two groups. Incidence of postoperative intra-abdominal collections was 11% in CA and 1% in UA. TULAA's cost was 192.07 €.

CONCLUSION

In our series, TULAA seems to be safe, feasible and cost-effective for both uncomplicated and complicated appendicitis, with no disadvantage in terms of outcomes compared to what is reported in literature for CLS.

Energy Devices for Clipless-Sutureless Laparoscopic Appendectomy: A Systematic Review and Meta-Analysis on Utility and Safety

Background and Objectives: While laparoscopic appendectomy is standardized, techniques for appendiceal stump closure and mesoappendix division remain variable. Novel vessel sealing techniques are increasingly utilized ubiquitously. We sought to systematically summarize all relevant data and to define the current evidence on the safety and utility of energy devices for clipless−sutureless laparoscopic appendectomy in this systematic review and meta-analysis. Materials and Methods: This review was conducted following the PRISMA guidelines. PubMed, Embase, Scopus, and Web of Science were systematically searched. Inclusion criteria included studies with laparoscopic appendectomy for appendicitis. The intervention included patients undergoing division of mesoappendix and/or securing of the appendicular base using diathermy (Monopolar or Bipolar or LigaSure Sealing Device) or Harmonic Scalpel (Group A) compared to patients undergoing division of mesoappendix and/or securing of the appendicular base using endoclip or Hem-o-lok or ligature (Group B). The methodological quality of the included studies was assessed using the Downs and Black scale. The outcomes of surgical site infection (SSI) or intra-abdominal collection, postoperative ileus, average operative duration, and length of hospital stay (LHS) were compared. Results: Six comparative studies were included; three were retrospective, two were prospective, and one was ambispective. Meta-analysis revealed a shorter operative duration in Group A with respect to appendicular base ligation (MD −12.34, 95% CI −16.57 to −8.11, p < 0.00001) and mesoappendix division (MD −8.06, 95% CI −14.03 to −2.09, p = 0.008). The pooled risk ratios showed no difference in SSI between groups. Additionally, no difference was observed in LHS. The risk of postoperative ileus was higher in group B regarding mesoappendix division (RR 0.56, 95% CI 0.34 to 0.93, p = 0.02), but no difference was found concerning appendicular base ligation. The included studies showed a moderate-to-high risk of bias. Conclusions: Clipless−sutureless laparoscopic appendectomy is safe and fast. Postoperative ileus seems less common with energy devices for mesoappendix division. However, the studies included have a moderate-to-high risk of bias. Further studies addressing the individual devices with surgeons of similar levels are needed.

Laparoscopic versus open appendicectomy for complicated appendicitis in children: A systematic review and meta-analysis

BACKGROUND

Laparoscopic appendectomy (LA) is the preferred approach in uncomplicated appendicitis. However, in patients with complicated appendicitis (CA), the best approach is still unclear though laparoscopy is being increasingly preferred over open appendicectomy (OA) nowadays.

AIM

To comprehensively review the current literature and compare the associations of LA and OA concerning various postoperative outcomes in order to determine the best approach for children with CA.

METHODS

The PRISMA guidelines were adhered to and an electronic database search was extensively performed. Data analysis, including subgroup analysis of randomized-control trials, was performed using RevMan 5.3. Methodological and statistical heterogeneity, as well as publication bias of the included studies, were assessed.

RESULTS

Four randomized controlled trials (266 LA versus 354 OA) and thirty-six case-controlled trials (2580 LA versus 3043 OA) were included in the analysis. Compared to OA, LA has a shorter length of stay, a lower rate of surgical site infection as well as a significantly lower overall complication rate. The rates of intraabdominal abscess formation, post-operative fever, pneumonia and ileus are similar in the two groups. So are the rates of readmissions and reoperations. LA was also shown to have a shorter time taken to oral intake and a lesser requirement of analgesics as well as intravenous antibiotics. Operative time for OA was found to be significantly shorter than that for LA.

CONCLUSION

This meta-analysis objectively demonstrates that laparoscopy has a better overall complication profile compared to OA and should be the procedure of choice in children with complicated appendicitis.

The uncharted severity of complications after appendectomy for acute appendicitis in children: results from 348 consecutive patients

Appendectomy is the most frequently performed emergent procedure in paediatric patients. However, there is a wide heterogeneity in outcome definitions and, conversely, a lack of information about complications' severity. This study aims to analyse the outcome of children operated for acute appendicitis, with reference to complications' severity grading. This is a retrospective analysis of a prospectively collected database including all children who underwent emergent appendectomy between September 2013 and March 2020. Postoperative complications were defined according to standardized definitions and graded following Clavien-Dindo classification (CDC). The outcome was analysed in terms of postoperative morbidity, severity of complications, hospital readmission and length of hospital stay (LOS). 348 patients were analysed. Postoperative complications occurred in 18 (5.2%) patients; superficial and organ/space surgical site infections represented the most frequent complications (1.7% and 2.9%, respectively). Major complications (CDC ≥ IIIa) were seen in 4 (1.1%) patients. Median postoperative LOS was 4 (iqr 3-5) days, while hospital readmission was 1.1%. Postoperative complications, preoperative C-reactive protein values and presence of drainage were significantly associated with longer LOS at multivariate analysis. No difference in incidence and severity of complications was found in relation to children's adolescent age. Major complications among paediatric patients undergoing appendectomy for acute appendicitis in a general surgery department are rare. The application of standardized definitions and severity-based grading of complications is crucial for outcome analysis: our results are a useful reference for comparison between forthcoming studies.

Are Postoperative Intravenous Antibiotics Indicated After Laparoscopic Appendicectomy for Simple Appendicitis? A Prospective Double-blinded Randomized Controlled Trial

BACKGROUND

There is limited evidence for the use of postoperative antibiotics for simple appendicitis (SA) in children. Our aim was to conduct a prospective double-blinded randomized controlled trial to investigate this after a laparoscopic appendicectomy.

METHODS

Following ethical approval, children (≤16 years) undergoing appendicectomy were recruited at a single institution. Patients were randomized intraoperatively to receive either 2 postoperative intravenous doses of placebo or antibiotics (Abx). All patients received a dose of Abx at induction of anesthesia. Primary outcome was the incidence of postoperative wound infection (WI), and secondary outcome was the incidence of intra-abdominal abscess formation. Data are reported as number of cases (%), median (range), relative risk, and analyzed using Mann Whitney U test, Chi-square test, as appropriate, a P-value ≤0.05 was considered significant.

RESULTS

A total of 304 patients were randomized. Sixty-one were subsequently excluded due to protocol violations or recruitment errors; therefore, 243 were included in the final analysis. One hundred twenty-two patients received placebo and 121 Intravenous Abx. There was no difference between the sex (50F/72 M vs 47F/74 M, P = 0.8), median age (12.4 vs 12.2 years, P = 0.5), and postoperative length of stay in a hospital (27.2 vs 25.6 hours, P = 0.7). There was also no difference in the preoperative blood results. A total of 9 WIs occurred: 8/122 (6.6%) placebo versus 1/121 (0.8%) Abx, P = 0.01 [relative risk for WI 7.9 (95% confidence interval: 1.0-62.4)]. There were no intra-abdominal abscess in either groups.

CONCLUSIONS

This prospective randomized double blinded randomized controlled trial has revealed a significant decrease in WI rates by giving 2 postoperative intravenous doses of Abx, suggesting postoperative Abx are of benefit in SA.

Pediatric appendectomy in developing countries: How does it differ from international experience?

Introduction

A review of the English literature indicates the faint superiority of laparoscopic (LA) over open appendectomy (OA) in the pediatric population; however, a developing-country's experience in the field is not available yet. This study presents our experience in LA versus OA over the last 7 years in one university hospital in Lebanon and compares our results to the international ones.

Method

A single center retrospective study was done including all patients aged less than 15 years who underwent appendectomy. A description of each operative technique is presented. Patients' characteristics, intraoperative finding, operative timing (OT), length of stay (LOS) and short term postoperative complications including surgical site infection (SSI) rate, intra-abdominal abscess formation (IAA) rate and reoperation rate were all studied. Statistical analysis was done using Chi-square or Fisher's exact test, as for continuous, Student's t test was used or one-way ANOVA in case of more than 2 categories.

Result

Appendectomy was performed in 84 patients. 52 patients underwent OA through a Rocky Davis incision, and 32 patients underwent a LA. We found an advantage of LA over OA in reducing SSI, otherwise both approaches were similar.

Conclusion

In accordance with international results, in our experience, LA is superior to OA only with regards to SSI.

Consensus Statement of the Italian Polispecialistic Society of Young Surgeons (SPIGC): Diagnosis and Treatment of Acute Appendicitis

Background: Acute appendicitis (AA) is one of the most common causes of abdominal pain requiring surgical intervention. Approximately 20% of AA cases are characterized by complications such as gangrene, abscesses, perforation, or diffuse peritonitis, which increase patients' morbidity and mortality. Diagnosis of AA can be difficult, and evaluation of clinical signs, laboratory index and imaging should be part of the management of patients with suspicion of AA.Methods: This consensus statement was written in relation to the most recent evidence for diagnosis and treatment of AA, performing a literature review on the most largely adopted scientific sources. The members of the SPIGC (Italian Polispecialistic Society of Young Surgeons) worked jointly to draft it. The recommendations were defined and graded based on the current levels of evidence and in accordance with the criteria adopted by the American College of Chest Physicians (CHEST) for the strength of the recommendations.Results: Fever and migratory pain tend to be present in patients with suspicion of AA. Laboratory and radiological examinations are commonly employed in the clinical practice, but today also scoring systems based on clinical signs and laboratory data have slowly been adopted for diagnostic purpose. The clinical presentation of AA in children, pregnant and elderly patients can be unusual, leading to more difficult and delayed diagnosis. Surgery is the best option in case of complicated AA, whereas it is not mandatory in case of uncomplicated AA. Laparoscopic surgical treatment is feasible and recommended. Postoperative antibiotic treatment is recommended only in patients with complicated AA.

Does peritoneal lavage influence the rate of complications following pediatric Laparoscopic Appendicectomy in Children with Complicated Appendicitis? A Prospective Randomized Clinical Trial

BACKGROUND

There is ongoing debate concerning the use of peritoneal irrigation in the setting of complicated appendicitis (CA) in children. Our aim was to conduct a prospective randomized controlled trial for the treatment of CA during a laparoscopic appendicectomy in children.

METHODS

Following ethical approval (REC10138B), pediatric patients (≤16 years old) were recruited from a single institution over a 3-year time period (2015-2018). Randomization occurred following intraoperative diagnosis of CA to either peritoneal lavage (PL) or suction only (SO). Primary outcome was the length of stay (LoS), and secondary outcomes were the presence of a postoperative intraabdominal abscess (IAA), wound infection (WI), or adhesive small bowel obstruction (ASBO). Data are reported as number of cases (%), median (range), odds ratio [OR] and analyzed using t-test and Fisher's exact test. A p-value ≤0.05 was considered significant.

RESULTS

A total of 100 pediatric patients were recruited into the trial. Sixteen were excluded owing to either recruitment or protocol violations, and therefore a total of 86 underwent final analysis: 44 PL and 42 SO. There was no significant difference in the LoS: 5.7 (PL) vs 5.6 (SO) days, p = 0.75. Only 1 IAA occurred in the PL group: 1/44(2.3%) vs 0/42(0%), p = 1.0. There was 1 ASBOs in the PL group (2.3%, p = 1.0) and no WIs in either of the groups.

CONCLUSION

This prospective randomized control trial has revealed equivalence in techniques for the treatment of complicated appendicitis. It has also revealed a low complication rate following pediatric LA with either PL or SO.

TYPE OF STUDY

Randomized controlled trial.

LEVEL OF EVIDENCE

Level I.

Early Laparoscopic Washout may Resolve Persistent Intra-abdominal Infection Post-appendicectomy

BACKGROUND

Intra-abdominal abscess (IAA) complicates 2-3% of patients having an appendicectomy. The usual management is prolonged antibiotics and drainage of the IAA. From 2006, our unit chose to use early re-laparoscopy and washout in patients with persistent sepsis following appendicectomy. The aims of this study were to assess the outcomes of early laparoscopic washout in patients with features of persistent intra-abdominal sepsis and compare those with percutaneous drainage and open drainage of post-appendicectomy IAA.

METHODS

A retrospective case note review was performed for all patients having a laparoscopic washout, percutaneous drainage or open drainage following appendicectomy between January 2006 and December 2017.

RESULTS

During the period, 4901 appendicectomies occurred. Forty-one (0.8%) patients had a laparoscopic washout, 16 (0.3%) had percutaneous drainage, and 6 (0.1%) had an open drainage. The demographics, ASA grade and pathology at initial appendicectomy were similar. The mean time after appendicectomy was significantly shorter for laparoscopic washout (4.1 days vs. 10.1 and 9.0 days, p = <0.003). The mean time for resolution of SIRS was significantly shorter (2.0 days vs. 3.3 and 5.2 days, p <0.02). The morbidity and length of stay were similar.

CONCLUSION

Early laparoscopic washout for persistent intra-abdominal sepsis may be an alternative to non-operative management and delayed intervention for IAA and may have better outcomes than either percutaneous drainage or open drainage. A prospective randomised comparison is required to further evaluate the indications and role of early laparoscopic washout post-appendicectomy.

Are Preoperative CT Findings Useful for Predicting Postoperative Intraabdominal Abscess in the Patients with Acute Appendicitis?

Background and objective: In patients with acute appendicitis (AA), preoperative computed tomography (CT) findings suggesting development of intraabdominal abscess (IAA) had not been widely used. The aim of this study was to investigate the preoperative clinical and radiological factors that predict the development of a postoperative IAA in patients with AA who were treated by laparoscopic appendectomy (LA). Methods: Two hundred and sixteen patients with pathologically proven AA underwent LA between January 2013 and March 2018 in our department. Medical records and preoperative CT images of these 216 patients were retrospectively reviewed and the predictive factors of postoperative IAA were investigated. In addition, patients were divided into complicated appendicitis (CA) and simple appendicitis (SA) and perioperative factors of two groups were compared. Results: One hundred and forty-seven patients were diagnosed with CA, while the other 69 patients were diagnosed with SA. Sixteen patients developed postoperative IAA in the CA group, while no patients in the SA group did. The univariate analysis revealed that time from onset to surgery more than 3 days (p = 0.011), the preoperative CT finding of periappendiceal fluid (p = 0.003), abscess (p < 0.001), and free air (p < 0.001), operation time more than 120 min (p = 0.023) and placement of a drainage tube (p < 0.001) were significantly associated with the development of IAA. Multivariate analysis revealed that the preoperative CT finding of free air was independently associated with the development of IAA (p = 0.007, odds ratio = 5.427, 95% CI: 1.586⁻18.57). Conclusions: IAA developed predominantly in patients with CA. Preoperative CT findings of free air was found to be an independent predictor for the development of IAA. Surgeons should be meticulous in managing the postoperative course of patients with this finding.

Trends in the Use of Laparoscopic Versus Open Paediatric Appendicectomy: A Regional 12-Year Study and a National Survey

BACKGROUND

In adult patients, it is generally accepted that laparoscopic appendicectomy (LA) is the predominant operative pathway in treating acute appendicitis. The case for a similar pathway utilising LA in children is less clear. We investigate usage, trends and complications after LA in children in a single co-located adult/paediatric centre with contemporaneous adults as controls.

METHODS

A retrospective case-control study was conducted over 12 years including patients who underwent appendicectomy, and the paediatric series (<16 years) was divided into age-groups-based quartiles. An anonymous questionnaire-based national survey was circulated among general and paediatric surgeons.

RESULTS

Of the 5784 appendicectomy patients, 2960 were children. LA rate in paediatric appendicitis was 65%. Yearly trends in LA reached a steady state in both groups after 2010 (Δ 0-1%/year). Rates of LA and LA IAA (respectively) differed significantly between age groups: 60, 3% (0-9 years); 65, 1% (10-13 years); 71, 2% (14-16 years) and 93, 3% (>16 years) (p = 0.001, 0.02). The national survey showed respondents believed LA was not superior to OA in paediatric patients except in terms of cosmesis. There was strong support in the use of LA in older children and children >40 kg.

CONCLUSION

The use of LA in paediatric appendicectomies in the study region is similar to international rates, but not increasing over time. Irish surgeons still favour OA in younger children and prefer a case-by-case approach rather LA being the preferred pathway. This is despite the regional and international evidence showing favourable outcomes with LA in children.

Laparoscopic Lavage Versus Suction Only in Complicated Acute Appendicitis: A Prospective Randomized Control Trial

Background:

Laparoscopic appendectomy for complicated appendicitis presents a challenge with concerns about pelvic collections. It is unclear whether lavage or if simple suctioning of pus influences complications.

Methods:

A prospective, single,-blinded, randomized control trial was conducted. Patients with suspected acute appendicitis were consented. Those found to have complicated appendicitis (perforation, localized pus, or four-quadrant pus) at laparoscopy were randomized to suction or lavage. Exclusions included conversions and drainage of abscess only. Lavage consisted of 3 liters of lavage. Intra-abdominal abscess that required reintervention (i.e., relook, percutaneous drainage) was the primary outcome. Hospital stay and return of bowel function were also recorded.

Results:

A total of 213 patients were assessed for eligibility. We excluded 157 patients, as they had simple appendicitis; 7 patients were converted to laparotomies; 5 had abscesses but the appendix was not removed. We analyzed 86 patients. The mean age was 26.6 years (14–74). We lavaged 42 (48.8%) patients and 44 (51.2%) were suctioned. Four-quadrant pus was present in 26 (30.2%) of the patients overall. Complications developed in 20 (47.5%) of the patients that were lavaged versus 12 patients (27.1%) with suction only. The difference did not reach significance due to sample size (P = 0.0739). Operative time was longer in the lavage group by 30 minutes (P = 0.086). If a complication developed, then the hospital stay was significantly prolonged 13.5 days versus 5 days (P &lt; 0.001). The study was stopped by the internal review board due to the excess risk with lavage.

Conclusions:

This exploratory study into lavage versus suction only in complicated appendicitis revealed potential harm with lavage. The study was stopped prematurely by the internal review due to the excess risk experienced by the lavage group, thus the study did not reach statistical power. If a patient with complicated appendicitis developed any complication, hospital stay was longer.

Streptococcus anginosus is associated with postoperative intraabdominal collections in appendicitis

AIM OF STUDY

Streptococcus anginosus group (SA) (formerly Streptococcus milleri) are pathogens recognised to have a high risk of postoperative collection in appendicitis, although little data exist specifically in children. We performed a retrospective review of all microbiological data from appendicectomies to assess whether there was an association in children.

METHODS

A retrospective case note review of patients admitted to a paediatric tertiary centre coded for appendicitis from January 2015 to October 2016 was completed. Initial length of stay (LOS), cumulative hospital days, histology, microbiology, and radiology reports were recorded. The postoperative antibiotic regimen was based on surgeon's choice and not standardised.

MAIN RESULTS

231 children were identified, and 18 were excluded. In the remainder, 169 (78.9%) had positive microbiology cultures, and of these 45 were positive for SA (26.6%). There was no significant variation in monthly incidence (P=0.58). Patients with SA+ve cultures were associated with complicated appendicitis on histology (P=0.01), longer LOS and cumulative hospital days (P=0.001), and increased likelihood of developing postoperative collections (P=0.001). The relative risk of developing a postoperative collection with SA+ve cultures was 2.40. There was no difference in time to presentation, histology, or intervention between SA and non-SA patients who developed collections. All SA cultures were sensitive to penicillin and erythromycin.

CONCLUSION

SA cultured from intraoperative serial swabs is associated with an increased risk of developing postoperative collection (2.40). Using this information with standardisation of antimicrobial management may reduce the rate of postoperative complications in paediatric appendicitis.

LEVEL OF EVIDENCE

Level II prognosis study.

A systematic review of the quality of conduct and reporting of systematic reviews and meta-analyses in paediatric surgery

OBJECTIVE

Our objective was to evaluate quality of conduct and reporting of published systematic reviews and meta-analyses in paediatric surgery. We also aimed to identify characteristics predictive of review quality.

BACKGROUND

Systematic reviews summarise evidence by combining sources, but are potentially prone to bias. To counter this, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was published to aid in reporting. Similarly, the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) measurement tool was designed to appraise methodology. The paediatric surgical literature has seen an increasing number of reviews over the past decade, but quality has not been evaluated.

METHODS

Adhering to PRISMA guidelines, we performed a systematic review with a priori design to identify systematic reviews and meta-analyses of interventions in paediatric surgery. From 01/2010 to 06/2016, we searched: MEDLINE, EMBASE, Cochrane, Centre for Reviews and Dissemination, Web of Science, Google Scholar, reference lists and journals. Two reviewers independently selected studies and extracted data. We assessed conduct and reporting using AMSTAR and PRISMA. Scores were calculated as the sum of reported items. We also extracted author, journal and article characteristics, and used them in exploratory analysis to determine which variables predict quality.

RESULTS

112 articles fulfilled eligibility criteria (53 systematic reviews; 59 meta-analyses). Overall, 68% AMSTAR and 56.8% PRISMA items were reported adequately. Poorest scores were identified with regards a priori design, inclusion of structured summaries, including the grey literature, citing excluded articles and evaluating bias. 13 reviews were pre-registered and 6 in PRISMA-endorsing journals. The following predicted quality in univariate analysis:, word count, Cochrane review, journal h-index, impact factor, journal endorses PRISMA, PRISMA adherence suggested in author guidance, article mentions PRISMA, review includes comparison of interventions and review registration. The latter three variables were significant in multivariate regression.

CONCLUSIONS

There are gaps in the conduct and reporting of systematic reviews in paediatric surgery. More endorsement by journals of the PRISMA guideline may improve review quality, and the dissemination of reliable evidence to paediatric clinicians.

Umbilical Negative Pressure Dressing for Transumbilical Appendectomy in Childern

Background and Objectives:

Transumbilical laparoscopic-assisted appendectomy (TULAA) carries a high risk for surgical site infection. We investigated the effect of a bio-occlusive umbilical vacuum dressing on wound infection rates after TULAA for patients with acute appendicitis and compared to it with a conventional 3-port appendectomy with a nonvacuum dressing.

Methods:

This study was a retrospective chart review of 1377 patients (2–20 years) undergoing laparoscopic appendectomy for acute appendicitis in 2 tertiary care referral centers from January 2007 through December 2012. Twenty-two different operative technique/dressing variations were documented. The 6 technique/dressing groups with >50 patients were assessed, including a total of 1283 patients.

Results:

The surgical site infection rate of the 220 patients treated with TULAA and application of an umbilical vacuum dressing with dry gauze is 1.8% (95% CI, 0.0–10.3%). This compares to an infection rate of 4.1% (95% CI, 1.3–10.5%) in 97 patients with dry dressing without vacuum. In the 395 patients who received an umbilical vacuum dressing with gauze and bacitracin, the surgical site infection rate was found to be 4.3% (95% CI, 2.7–6.8%).

Conclusions:

Application of an umbilical negative-pressure dressing with dry gauze lowers the rate of umbilical site infections in patients undergoing transumbilical laparoscopic-assisted appendectomy for acute appendicitis.

Irrigation versus suction alone during laparoscopic appendectomy; A randomized controlled equivalence trial

INTRODUCTION

The objective of this study was to compare operative peritoneal irrigation versus suction alone during laparoscopic appendectomy in adult patients; our hypothesis was that the two methods are equivalent in terms of rate of post-operative intra-abdominal abscess. There has been only one prospective, randomized, superiority trial in children, that showed non-significant difference in the rate of intra-abdominal abscess comparing irrigation to suction alone during laparoscopic appendectomy for perforated appendicitis. Non-significant difference in a superiority trial does not imply equivalence.

METHODS

This was a single-institution, prospective, randomized controlled equivalence study based on a null-hypothesis of non-equivalence between irrigation and suction alone. Adult patients with intra-operative findings of an acutely inflamed appendix, with suppuration or perforation localized to the right iliac fossa, paracolic gutter or pelvis were randomized to irrigation or suction alone. The primary endpoint was the rate of intra-abdominal abscess. An unconditional exact test of equivalence was used to test the null-hypothesis.

RESULTS

Eighty-one patients were included for analysis. Two (5%) of 40 patients in the irrigation group and two (4.9%) of 41 in the suction-only group developed postoperative intra-abdominal abscess. The 95% confidence interval for the difference between the two groups was -0.1200 to 0.1244, captured within the pre-defined δ limits (-0.15, 0.15). With reference to the rate of intra-abdominal abscess, equivalence was demonstrated between irrigation and suction-only techniques.

CONCLUSIONS

In patients with suppurative or perforated appendicitis, the rate of intra-abdominal abscess is equivalent between groups treated with peritoneal irrigation and suction alone.

Trends in the Diagnosis and Management of Pediatric Appendicitis

• On the basis of class B evidence and consensus, acute appendicitis in children can often be diagnosed clinically with only selective use of imaging. (13)(14)(15)(16) • On the basis of class B evidence and consensus, ultrasonography is the test of choice when acute appendicitis is suspected but is unclear based on history, physical examination, and laboratory results. (17)(18)(19) • On the basis of class B evidence and consensus, the use of computed tomography scan should be limited to cases of suspected complex appendicitis with abscess or when there is clinical suspicion for acute appendicitis but ultrasonography results are not helpful. (16) • On the basis of class C evidence and consensus, children with possible appendicitis ideally should be treated in medical centers that have skilled sonographic personnel. (21) • On the basis of class B evidence and consensus, simple appendicitis should be treated by appendectomy during normal operating hours. Preoperative treatment with intravenous antibiotics and fluids during the overnight hours halts disease progression and allows for the safest surgery with the benefit of a full and rested staff. (24)(25)(26) • On the basis of class B evidence and consensus, complex appendicitis with a well-defined abscess can be treated nonoperatively initially, with the option of an interval appendectomy after recovery from the acute infection. (29)(30) (31)(32)(33)

Outcome reporting in randomised controlled trials and meta-analyses of appendicitis treatments in children: a systematic review

Background

Acute appendicitis is the most common surgical emergency in children. Despite this, there is no core outcome set (COS) described for randomised controlled trials (RCTs) in children with appendicitis and hence no consensus regarding outcome selection, definition and reporting. We aimed to identify outcomes currently reported in studies of paediatric appendicitis.

Methods

Using a defined, sensitive search strategy, we identified RCTs and systematic reviews (SRs) of treatment interventions in children with appendicitis. Included studies were all in English and investigated the effect of one or more treatment interventions in children with acute appendicitis or undergoing appendicectomy for presumed acute appendicitis. Studies were reviewed and data extracted by two reviewers. Primary (if defined) and all other outcomes were recorded and assigned to the core areas ‘Death’, ‘Pathophysiological Manifestations’, ‘Life Impact’, ‘Resource Use’ and ‘Adverse Events’, using OMERACT Filter 2.0.

Results

A total of 63 studies met the inclusion criteria reporting outcomes from 51 RCTs and nine SRs. Only 25 RCTs and four SRs defined a primary outcome. A total of 115 unique and different outcomes were identified. RCTs reported a median of nine outcomes each (range 1 to 14). The most frequently reported outcomes were wound infection (43 RCTs, nine SRs), intra-peritoneal abscess (41 RCTs, seven SRs) and length of stay (35 RCTs, six SRs) yet all three were reported in just 25 RCTs and five SRs. Common outcomes had multiple different definitions or were frequently not defined. Although outcomes were reported within all core areas, just one RCT and no SR reported outcomes for all core areas. Outcomes assigned to the ‘Death’ and ‘Life Impact’ core areas were reported least frequently (in six and 15 RCTs respectively).

Conclusions

There is a wide heterogeneity in the selection and definition of outcomes in paediatric appendicitis, and little overlap in outcomes used across studies. A paucity of studies report patient relevant outcomes within the ‘Life Impact’ core area. These factors preclude meaningful evidence synthesis, and pose challenges to designing prospective clinical trials and cohort studies. The development of a COS for paediatric appendicitis is warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-0783-1) contains supplementary material, which is available to authorized users.