Risk Factors for Intra-abdominal Abscess Development Following Laparoscopic Appendectomy, a Systematic Review and Meta-analysis

Aims: To determine and analyze the risk factors for the development of intra-abdominal abscess for patients who underwent laparoscopic appendectomy. Methods: The PRISMA guidelines were adhered to. Inclusion and exclusion criteria were defined prior to data gathering and were used to search the PubMed, Cochrane, and EBSCOHost databases to extract relevant data. The quality of all selected research articles and the risk of bias (RoB) were assessed and rated as poor, fair, or good using the Newcastle-Ottawa Scale (NOS) for cohort studies. Publication bias was graphically analyzed using contour-enhanced funnel plots. Results: Five retrospective cohort studies were included in this study. Majority of the included studies had low levels of attrition bias (0%), reporting bias (0%), and other biases (0%). However, there was a moderate to high risk of selection bias attributable to random sequence generation (60%) and allocation concealment (60%), performance bias due to lack of participant and personnel blinding (40%), and detection bias attributable to lack of outcome assessor blinding (60%). Formal statistical tests for publication bias using Begg’s adjusted rank correlation test and Egger’s regression asymmetry test were not statistically significant, indicating that the likelihood of publication bias was unlikely in all study outcome. In the combined analysis IAA formation was not statistically significant based on Age, Sex, BMI, ASA classification, presence of diabetes mellitus, and symptom duration p =0.160, 95% CI = –0.22 – 1.35; p =0.952, 95% CI = 0.95 – 1.06; p =0.098, 95% CI = –0.12 – 1.38; p =0.865, 95% CI = 0.93 – 1.09; p =0.892, 95% CI = 0.83–1.24; p =0.384, 95% CI = –0.16 – 0.41 respectively). Moreover, C-reactive protein and White blood cell count were not statistically significant in the development of IAA post-operatively ( p =0.303, 95% CI = –1.78 – 5.73; p =0.257, 95% CI = –0.52 – 1.93). Status of appendix intraoperatively: suppurative, gangrenous, or ruptured had 7% increase in the likelihood for the development of IAA, particularly for gangrenous and ruptured appendix, but was still not statistically significant ( p =0.441, 95% CI = 0.95 – 1.12; p =0.329, 95% CI = 0.94 – 1.22). Operative time and antibiotic duration in intraabdominal abscess also had no statistical difference in the development of IAA ( p =0.243, 95% CI = –1.15 – 4.55; p =0.220, 95% CI = –0.41 – 1.78). Conclusion: Sex, age, ASA classification, BMI, presence of diabetes mellitus, duration of symptoms, CRP and WBC values, status of appendix intraoperatively, operative time, conversions, drainage, and duration of antibiotics in days had no significant risk in the development of intra abdominal abscess following laparoscopic appendectomy. Perforated appendicitis identified intra-operatively may increase the risk of intra abdominal abscess post laparoscopic appendectomy but the difference is not statistically significant.