Effect of peritoneal drainage on the prognosis following appendectomy in pediatric patients with appendicitis: a retrospective study based on appendicitis grade

Background: This study aimed to assess the impact of peritoneal drainage and its type on prognosis, encompassing postoperative recovery and complications, in pediatric patients (≤ 16 years old) following appendectomy based on the grade of appendicitis. Methods: In this retrospective study, we analyzed pediatric patients (≤ 16 years old) with appendicitis who met the inclusion and exclusion criteria in our center from January 2017 to January 2024 and classified them into grade I–V based on the grade of appendicitis, with V representing the most serious cases. The patients were grouped according to drainage status and type. The main clinical outcomes included postoperative rehabilitation indexes such as time to resume a soft diet, time to remove the drain, duration of postoperative antibiotic use and length of hospitalization (LOH), as well as postoperative complications including intra-abdominal abscess (IAA), ileus and wound infection (WI), and readmission within 30 days after surgery. Results: A total of 385 pediatric patients with appendicitis were included in the study and divided into No-drainage (ND) group (n = 74), Passive drainage (PD) group (n = 246) and Active drainage (AD) group (n = 65) according to drainage status and type. Compared to the other two groups, the ND group had a significantly shorter time to resume a soft diet, duration of postoperative antibiotic use and LOH, and these differences were statistically significant. Similar findings were observed in grade I patients too (P < 0.05). In all cases examined here, the AD group had a significantly shorter time for drain removal compared to the PD group (3.04 [1–12] vs 2.74 [1–15], P = 0.049); this difference was also evident among grade I patients (2.80 [1–6] vs 2.47 [1–9], P = 0.019). Furthermore, within the same grade, only in grade IV did the AD group exhibit a shorter duration of postoperative antibiotic use compared to the PD group (4.75 [4–5] vs 8.33 [5–15], P = 0.009). Additionally, the LOH in the AD group was longer than that in the PD group (8.00 [4–13] vs 4.75 [4–5], P = 0.025). Among all cases, the ND group exhibited significantly lower incidences of overall complications and WI compared to the other two groups (P < 0.05). Additionally, the incidence of IAA in the ND group was significantly lower than that in the PD group (0% vs 5.3%, P = 0.008 < 0.0167). Furthermore, although there were no statistically significant differences in the incidence of overall complications, IAA, ileus, and WI between the PD and AD groups during grade ≥ II analysis (P > 0.05), a higher readmission rate within 30 days was observed in the PD group compared to the AD group; however, these differences were not statistically significant (P > 0.05). Moreover, multivariate analysis revealed that a higher grade of appendicitis was associated with an increased risk of overall complications and IAA as well as a longer duration of postoperative antibiotic use and LOH. Conclusion: The appendicitis grade is a crucial indicator for predicting postoperative IAA and LOH. In patients with grade I appendicitis, peritoneal drainage, even if active drainage, is not recommended; For patients with grade ≥ II appendicitis, active drainage may be more effective than passive drainage in reducing the duration of postoperative antibiotic use and LOH.