Peritoneal lavage during laparoscopic appendectomy for complex appendicitis is associated with increased post-operative morbidity

AIM

Appendicitis is one of the most common paediatric surgical pathologies seen by paediatric surgeons worldwide. Laparoscopic appendectomy is undertaken for all cases of appendicitis in our institute. Intraperitoneal lavage following appendectomy is the conventional way of managing complicated appendicitis; however, some surgeons debate the efficacy of this practice. The aim of this study was to compare outcomes of intraperitoneal lavage versus suction only in children with complicated appendicitis.

METHODS

Data were collected retrospectively between January 2018 and January 2019. All patients undergoing laparoscopic appendectomy for complex appendicitis were included and divided into two groups, patients who had suction only and those who had lavage and suction. Outcome parameters studied were the length of stay (LOS), number of temperature spikes > 37.7 (TS), operative times (OT) and readmission for intra-abdominal collections. Comparison between the two groups was performed using two sample t-test with unequal variance, significance was set at P < 0.05.

RESULTS

A total of 115 patients were included (lavage n = 52, Suction n = 63). The LOS (P = 0.0054), TS (0.0109), OT (P < 0.0001) were significantly higher in the lavage group compared to the suction-only group. Overall rates of readmission were similar between groups, however, readmission for the confirmed intra-abdominal collection was more common in the lavage group.

CONCLUSION

Based on our study, it appears that there is no advantage in performing an intraperitoneal lavage for complex appendicitis. It resulted in a prolonged stay, more post-operative TS and longer operative duration. The likelihood of being readmitted with an intra-abdominal collection following a lavage was higher compared to suction only.

Accuracy of ultrasonography for differentiating between simple and complex appendicitis in children

PURPOSE

Accurate differentiation between simple and complex appendicitis is important since differences in treatment exist. This study aimed to assess the accuracy of ultrasonography in differentiating between simple and complex appendicitis.

METHODS

Data from children aged < 18 years who underwent appendectomy between the 1st of January 2013 and the 1st of January 2018 were analyzed retrospectively. Ultrasonography reports of eligible children were divided into simple (test negative) and complex appendicitis (test positive) based on predefined criteria and compared to a gold standard (a combination of predefined perioperative and histopathological criteria). Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) were calculated to measure ultrasonographic accuracy in differentiating between simple and complex appendicitis.

RESULTS

176 children were eligible for inclusion. The mean age at the time of operation was 10.1 ± SD 4.6 years. 84 (47.7%) children had simple appendicitis and 92 (52.3%) had complex appendicitis. The use of ultrasonography yielded a sensitivity: 46%, specificity: 90%, PPV: 84%, and NPV: 60%.

CONCLUSION

Ultrasonography as standalone modality is not suitable for differentiating between simple and complex appendicitis in children. To improve preoperative differentiation, other variables such as clinical signs and laboratory data are necessary in conjunction with ultrasonography findings.

Effectiveness of a clinical pathway for pediatric complex appendicitis based on antibiotic stewardship principles

PURPOSE

Outcomes and resource utilization were evaluated after implementing a novel complex appendicitis (CA) pathway limiting postoperative antibiotics based on clinical parameters.

METHODS

Children with intraoperative CA (gangrenous, perforated, or abscess) were treated with intravenous antibiotics postoperatively until clinical criteria were met, without utilizing CBC or oral antibiotics at discharge. An interrupted time series (pre-intervention, transition, post-intervention) was used to assess outcomes. Hospital length of stay (LOS) was analyzed using segmented regression. Intra-abdominal abscess and readmission rates were analyzed using non-inferiority and multivariate logistic regression.

RESULTS

Five hundred ten children were included with a median age of 10 [IQR7-12] years. There were no differences in postoperative LOS (slope - 0.008; p = 0.855), intra-abdominal abscess rate (5% vs. 8%; p = 0.135), or readmission rate (12% vs. 8%; p = 0.113) across time periods which remained true when adjusting for age, gender, and intraabdominal disease severity. Post-intervention outcomes were not inferior to pre-intervention, abscess rate (p = 0.002), or readmission rate (p < 0.001). Intraoperative findings of perforation (OR9.0; 95% CI1-71; p = 0.044) and perforation with abscess (OR18.2; 95% CI2-36; p = 0.005) were associated with a greater likelihood of postoperative abscess compared to gangrenous appendicitis.

CONCLUSION

A CA protocol based on clinical parameters is safe and effective, resulting in similar intra-abdominal abscess and readmission rates compared to more resource-intense regimens.

LEVEL OF EVIDENCE

III TYPE OF RESEARCH: Interrupted Time Series.

Systematic Review and Meta-Analysis of Postoperative Antibiotics for Patients with a Complex Appendicitis

Postoperative antibiotics are recommended after appendectomy for complex appendicitis to reduce infectious complications. The duration of this treatment varies considerably between and even within institutions. The aim of this review was to critically appraise studies on duration of antibiotic treatment following appendectomy for complex appendicitis. A systematic literature search according to the PRISMA guidelines was performed. Comparative studies evaluating different durations of postoperative antibiotic therapy. Primary endpoint was intra-abdominal abscess (IAA) after appendectomy. Secondary endpoints were surgical site infection, readmission and length of hospital stay. The quality of evidence was assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool. Pooled event rates were calculated using a random-effects model. Nine studies reporting 2006 patients with complex appendicitis were included. The methodological quality of the included articles was poor. IAA was seen in 138 patients (8,6%). Meta-analysis revealed a statistically significant difference in IAA incidence between antibiotic treatment of ≤5 vs. >5 days (risk ratio (OR) 0.36 [95% CI 0.23-0.57] (p < 0.0001)) but not between ≤3 vs. >3 days (OR 0.81 [95% CI 0.38-1.74] (p = 0.59)). Descriptive statistics were used for secondary endpoints. The duration of postoperative antibiotic treatment is not associated with IAA following appendectomy for complex appendicitis.

Gangrenous appendicitis: No longer complicated

BACKGROUND

Appendicitis presents on a spectrum ranging from inflammation to gangrene to perforation. Studies suggest that gangrenous appendicitis has lower postoperative infection rates relative to perforated cases. We hypothesized that gangrenous appendicitis could be successfully treated as simple appendicitis, reducing length of stay (LOS) and antibiotic usage without increasing postoperative infections.

METHODS

In February 2016, we strictly defined complex appendicitis as a hole in the appendix, extraluminal fecalith, diffuse pus or a well-formed abscess. We switched gangrenous appendicitis to a simple pathway and reviewed all patients undergoing laparoscopic appendectomy for 12 months before (Group 1) and 12 months after (Group 2) the protocol change. Data collected included demographics, appendicitis classification, LOS, presence of a postoperative infection, and 30-day readmissions.

RESULTS

Patients in Group 1 and Group 2 were similar, but more cases of simple appendicitis occurred in Group 2. Average LOS for gangrenous appendicitis patients decreased from 2.5 to 1.4 days (p < 0.001) and antibiotic doses decreased from 5.2 to 1.3 (p < 0.001). Only one gangrenous appendicitis patient required readmission, and one patient in each group developed a superficial infection; there were no postoperative abscesses.

CONCLUSIONS

Gangrenous appendicitis can be safely treated as simple appendicitis without increasing postoperative infections or readmissions.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level II.

Two versus five days of antibiotics after appendectomy for complex acute appendicitis (APPIC): study protocol for a randomized controlled trial

Background

Acute appendicitis is one of the most common indications for emergency surgery. In patients with a complex appendicitis, prolonged antibiotic prophylaxis is recommended after appendectomy. There is no consensus regarding the optimum duration of antibiotics. Guidelines propose 3 to 7 days of treatment, but shorter courses may be as effective in the prevention of infectious complications. At the same time, the global issue of increasing antimicrobial resistance urges for optimization of antibiotic strategies. The aim of this study is to determine whether a short course (48 h) of postoperative antibiotics is non-inferior to current standard practice of 5 days.

Methods

Patients of 8 years and older undergoing appendectomy for acute complex appendicitis – defined as a gangrenous and/or perforated appendicitis or appendicitis in presence of an abscess – are eligible for inclusion. Immunocompromised or pregnant patients are excluded, as well as patients with a contraindication to the study antibiotics. In total, 1066 patients will be randomly allocated in a 1:1 ratio to the experimental treatment arm (48 h of postoperative intravenously administered (IV) antibiotics) or the control arm (5 days of postoperative IV antibiotics). After discharge from the hospital, patients participate in a productivity-cost-questionnaire at 4 weeks and a standardized telephone follow-up at 90 days after appendectomy. The primary outcome is a composite endpoint of infectious complications, including intra-abdominal abscess (IAA) and surgical site infection (SSI), and mortality within 90 days after appendectomy. Secondary outcomes include IAA, SSI, restart of antibiotics, length of hospital stay (LOS), reoperation, percutaneous drainage, readmission rate, and cost-effectiveness. The non-inferiority margin for the difference in the primary endpoint rate is set at 7.5% (one-sided test at ɑ 0.025). Both per-protocol and intention-to-treat analyses will be performed.

Discussion

This trial will provide evidence on whether 48 h of postoperative antibiotics is non-inferior to a standard course of 5 days of antibiotics. If non-inferiority is established, longer intravenous administration following appendectomy for complex appendicitis can be abandoned, and guidelines need to be adjusted accordingly.

Trial registration

Dutch Trial Register, NTR6128. Registered on 20 December 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2629-0) contains supplementary material, which is available to authorized users.

Composition of the cellular infiltrate in patients with simple and complex appendicitis

BACKGROUND

It is now well established that there are two types of appendicitis: simple (nonperforating) and complex (perforating). This study evaluates differences in the composition of the immune cellular infiltrate in children with simple and complex appendicitis.

MATERIALS AND METHODS

A total of 47 consecutive children undergoing appendectomy for acute appendicitis between January 2011 and December 2012 were included. Intraoperative criteria were used to identify patients with either simple or complex appendicitis and were confirmed histopathologically. Immune histochemical techniques were used to identify immune cell markers in the appendiceal specimens. Digital imaging analysis was performed using Image J.

RESULTS

In the specimens of patients with complex appendicitis, significantly more myeloperoxidase positive cells (neutrophils) (8.7% versus 1.2%, P < 0.001) were detected compared to patients with a simple appendicitis. In contrast, fewer CD8+ T cells (0.4% versus 1.3%, P = 0.016), CD20 + cells (2.9% versus 9.0%, P = 0.027), and CD21 + cells (0.2% versus 0.6%, P = 0.028) were present in tissue from patients with complex compared to simple appendicitis.

CONCLUSIONS

The increase in proinflammatory innate cells and decrease of adaptive cells in patients with complex appendicitis suggest potential aggravating processes in complex appendicitis. Further research into the underlying mechanisms may identify novel biomarkers to be able to differentiate simple and complex appendicitis.

A scoring system to predict the severity of appendicitis in children

BACKGROUND

It appears that two forms of appendicitis exist. Preoperative distinction between the two is essential to optimize treatment outcome. This study aimed to develop a scoring system to accurately determine the severity of appendicitis in children.

MATERIALS AND METHODS

Historical cohort study of pediatric patients (aged 0-17 y old) with appendicitis treated between January 2010 and December 2012. Division into simple, complex appendicitis, or another condition based on preset criteria. Multiple logistic regression analysis was used to build the prediction model with subsequent validation.

RESULTS

There were 64 patients with simple and 66 with complex appendicitis. Five variables explained 64% of the variation. Independent validation of the derived prediction model in a second cohort (55 simple and 10 complex appendicitis patients) demonstrated 90% sensitivity (54-99), 91% specificity (79-97), a positive predictive value of 64% (36-86), and an negative predictive value of 98% (88-100). The likelihood ratio+ was 10 (4.19-23.42), and likelihood ratio- was 0.11 (0.02-0.71). Diagnostic accuracy was 91% (84-98).

CONCLUSIONS

Our scoring system consisting of five variables can be used to exclude complex appendicitis in clinical practice if the score is <4.

Does delay in appendectomy affect surgical site infection in children with appendicitis?

PURPOSE

The purpose of this study was to investigate the association between time from diagnosis to operation and surgical site infection (SSI) in children undergoing appendectomy.

METHODS

Pediatric patients undergoing appendectomy in 2010-2012 were included. We collected data on patient demographics; length of symptoms; times of presentation, admission and surgery; antibiotic administration; operative findings; and occurrence of SSI.

RESULTS

1388 patients were analyzed. SSI occurred in 5.1% of all patients, 1.4% of simple appendicitis (SA) patients, and 12.4% of complex appendicitis (CA) patients. SSI did not increase significantly as the length of time between ED triage and operation increased (all patients, p=0.51; SA patients, p=0.91; CA patients, p=0.44) or with increased time from admission to operation (all patients, p=0.997; SA patients, p=0.69; CA patients, p=0.96). However, greater length of symptoms was associated with an increased risk of SSI (p<0.05 for all, SA and CA patients). In univariable analysis, obesity, and increased admission WBC count were each associated with significantly increased SSI. In multivariable analysis, only CA was a significant risk factor for SSI (p<0.0001).

CONCLUSION

We found no significant increase in the risk of SSI related to delay in appendectomy. A future multi-institutional study is planned to confirm these results.