Predictors of peritoneal lavage use in pediatric open appendectomy: A retrospective study

JCTEI JOURNAL OF CLINICAL TRIALS AND EXPERIMENTAL INVESTIGATIONS 69 Year: 2025 Volume: 4 Issue: 3 10.5281/ zenodo.17148273 Predictors of peritoneal lavage use in pediatric open appendectomy: A retrospective study ORIGINAL ARTICLE Sevgi Ulusoy Tangul¹, Hulya Ipek², Atilla Senayli¹ 1. Department of Pediatric Surgery, Faculty of Medicine, Kırklareli University, Kırklareli, Turkey 2. Department of Pediatric Surgery, Faculty of Medicine, Corum Hitit University, Çorum, Turkey Abstract Objective: This study aims to identify the clinical and diagnostic parameters influencing the decision to perform peritoneal lavage during pediatric open appendectomy. Materials and methods: The files of patients who underwent open appendectomy due to acute appendicitis were retrospectively scanned. The patients were divided into two groups based on whether peritoneal lavage was performed. Age, gender, accompanying symptoms, physical examination findings, hemoglobin, leukocyte, C-reactive protein (CRP), abdominal ultrasonography (USG), abdominal tomography (CT) findings, intraoperative findings, and hospital stay duration of the groups were recorded. Results: The mean age and hemoglobin values of the peritoneal lavage group were statistically significantly lower than those without lavage (p<0.05). Fever, vomiting, nausea, diarrhea, rebound, and CRP were higher in the lavage group (p<0.05). Leukocyte count and symptom onset time were statistically significantly lower in the no-lavage group (p<0.05). A statistically significant negative correlation existed between age, hemoglobin, CRP levels, and peritoneal lavage. There was a statistically significant and positive relationship with other parameters (p<0.05). According to the results of binary logistic analysis, CT and hemoglobin parameters were also substantial in multivariate analysis (p<0.05). Conclusion: While many factors affect the decision to perform peritoneal lavage in univariate analysis, CT findings and hemoglobin levels are significant parameters in multivariate analysis. Cite as: Ulusoy Tangul S, Ipek H, Senayli A. Predictors of peritoneal lavage use in pediatric open appendectomy: A retrospective study. J Clin Trials Exp Investig. 2025;4(3):69-76. Correspondence Sevgi Ulusoy Tangul, Department of Pediatric Surgery, Faculty of Medicine, Kırklareli University, Kırklareli, Turkey. e-mail [email protected] Received: 24 July 2025 Revised: 12 August 2025 Accepted: 29 August 2025 Published: 30 September 2025 Keywords @Appendectomy @peritoneal lavage @pediatrics ORCID ID of the author(s): SUT: 0000-0003-4573-1504 HI: 0000-0002-3496-8939 AS: 0000-0002-9994-8162 2822-5090 /© 2025 Journal of Clinical Trials and Experimental Investigations. Published by Unico's Medicine. This is an openaccess article under the terms of the CC BY license. (https://creativecommons.org/licenses/by/4.0/) 70 JCTEI Introduction Peritoneal lavage refers to the intraoperative practice of irrigating the peritoneal cavity, typically with saline or antiseptic solutions, to assist in clearing contaminants during abdominal surgery (1,2). In the context of appendicitis, this maneuver is often applied during surgery in cases with evident purulent material or perforation, rather than as a standard prophylactic intervention (3-8). Despite its frequent use in clinical practice, evidence remains inconclusive regarding its benefit in reducing postoperative complications such as intra-abdominal abscess or adhesions, particularly in pediatric populations (9-12). Many surgeons subscribe to the long-standing surgical notion that dilution resolves contamination; however, current evidence does not substantiate this belief (1). Although current moderate-quality evidence does not support the routine use of intraoperative peritoneal lavage in patients with appendicitis, many surgeons continue to perform this procedure as part of standard surgical practice (1,12,13). The benefits of saline-based intraoperative peritoneal lavage for patients with peritonitis remain uncertain (1,2). Peritoneal lavage with various liquids, with or without antibiotics, is frequently performed to prevent intra-abdominal abscess formation after appendectomy. However, studies show that peritoneal irrigation does not significantly affect intra-abdominal abscess formation after appendectomy (2). Robust scientific evidence indicates that saline-based intraoperative peritoneal lavage can extend operative time by an average of approximately 10 minutes, suggesting that this may have important clinical and logistical implications for surgical care (1,14). This study aims to identify the factors influencing the decision to perform peritoneal lavage during open appendectomy in pediatric patients and to evaluate, through multivariate analysis, the impact of this intervention on relevant clinical and disease-related outcomes. Materials and methods We retrospectively reviewed medical records of pediatric patients (ages 0–18) who underwent open appendectomy for acute appendicitis with intraoperative confirmation of acute appendicitis at two tertiary care centers between 2016 and 2023. Patients were grouped based on whether peritoneal lavage was performed intraoperatively. Inclusion criteria were: age under 18 years, intraoperative confirmation of acute appendicitis, and availability of complete medical records. Exclusion criteria were: incomplete clinical data, history of previous abdominal surgery, concomitant intra-abdominal conditions requiring alternative surgical procedures, cases converted from laparoscopic to open appendectomy, and patients who underwent laparoscopic appendectomy. The collected data included age, sex, clinical symptoms, physical examination findings, laboratory values (hemoglobin, leukocyte count, C-reactive protein), imaging results (ultrasonography, computed tomography), intraoperative findings, and length of hospital stay. Statistical analysis Frequency analysis was used to define nominal and ordinal data and mean, and standard deviation values were used to define measurement data. The Chi-Square Likelihood Ratio and Fischer's Exact tests were used to analyze ordinal and nominal data. Kolmogorov Smirnov Test was used to analyze the normality of measurement data. In the difference analysis of the measurement values, nonparametric tests were performed because the distributions did not comply with the normal distribution. Mann Whitney U Test was used in difference analysis between groups, and Spearman's rho correlation was used for correlation analyses. Binary logistic regression analysis was performed to identify independent predictors of performing peritoneal lavage. Variables with a p-value < 0.10 in the univariate analyses were entered into the multivariate model. In our logistic model dependent variable selected as peritoneal lavage (1=peritoneal lavage, 0= non-peritoneal lavage) and the independent variables included as age, fever, vomiting, nausea, diarrhea, rebound, leukocyte count, hemoglobin level, symptom duration, CRP level, CT findings, USG findings, presence of purulent material, omentectomy, and hospitalization duration. Results were expressed as odds ratios (OR) with 95% confidence intervals (CI). During model fitting, the variables “Purulent” and “Omentectomy” demonstrated complete separation (i.e., no events in one comparison group), which resulted in unstable parameter estimates and inflated standard errors. These variables were retained in the table for transparency, but their OR values should be interpreted with caution. Model fit was assessed using the –2 Log Likelihood, Cox & Snell R², and Nagelkerke R² values. All analyses were conducted using SPSS version 17.0 for Windows (IBM Corp., Armonk, NY, USA), with a significance level set at p<0.05. Ethical approval An ethical compliance certificate was received from Yozgat Bozok University Non-Interventional Clinical Research Ethics Committee, dated 08/05/2024, with decision number 2024-GOKAEK-243_2024.05.08_48. 71 JCTEI Results A total of 129 pediatric patients who underwent appendectomy were included in the study; after 102 patients were excluded according to the exclusion criteria; of these, 60 (46.5%) underwent peritoneal lavage and 69 (53.5%) did not. The overall mean age was 11.85±3.56 years, with the lavage group being significantly younger than the non-lavage group (10.67±4.03 vs. 12.86±2.76 years; p=0.002). Females accounted for 51.7% of the lavage group and 37.7% of the non-lavage group (p=0.078) (Table 1). The mean hemoglobin level in the peritoneal lavage group was 11.55±1.66 g/dL, which was significantly lower than that of the non-lavage group (12.57±1.69 g/dL; p<0.05). Fever, vomiting, nausea, diarrhea, rebound, and CRP elevation were higher in the lavage group, and the differences between the groups were significant (p<0.05). Leukocyte levels and time to onset of symptoms were statistically significantly lower in the no-lavage group. (p<0.05) (Table 1). Purulent fluid was seen only in the lavage group (p<0.05). The duration of hospital stay was also statistically significantly higher in the peritoneal lavage group (p<0.05) (Table 2). In correlation analysis, age, hemoglobin, and CRP levels were inversely associated with peritoneal lavage, while all other factors showed a significant positive correlation (p<0.05). The correlation analysis indicates that there is no multicollinearity present in the model, as the variance inflation factor (VIF) scores for all predictors are below the threshold of 5, suggesting that the predictors are not highly correlated with each other. The correlation matrix can be seen in Figure 1. There was a statistically significant and positive relationship with other parameters (p<0.05) (Table 3). Among the parameters that had a significant relationship with peritoneal washing in univariate analysis, only abdominal tomography and hemoglobin parameters were also substantial in multivariate analysis (p<0.05). The logistic regression table also included the variables “Purulent” and “Omentectomy,” which showed complete separation and produced unstable parameter estimates due to the absence of cases in one group. Therefore, their reported OR values should be interpreted with caution. Cox & Snell and Nagelkerke's R2 values showed that the model had high explanatory power. Therefore, when all parameters related to the patients were considered, CT results and hemoglobin levels were significant in deciding on peritoneal irrigation (Table 4). Discussion The primary objective of this study was to perform a multivariate analysis of the factors influencing the surgeon’s decision to perform peritoneal lavage during pediatric appendectomy. Our analysis demonstrated that hemoglobin level and abdominal CT findings were independent predictors, thereby achieving the primary endpoint. Specifically, the presence of purulent fluid and preoperative indicators such as low hemoglobin and abnormal CT results were strongly associated with the decision to perform lavage. While lower hemoglobin levels were significantly more common in the lavage group, there is no universally accepted cut-off value for this parameter, and it should be interpreted within the broader clinical and intraoperative context. Importantly, this study was not designed to assess the efficacy of lavage in preventing postoperative complications, as no follow-up outcome data were collected; therefore, these results primarily reflect surgical practice patterns rather than interventional outcomes. Although peritoneal lavage did not influence postoperative infection rates in our cohort, it was associated with longer hospitalization, which may have economic and logistical implications in pediatric surgical care. This finding highlights the importance of weighing potential benefits against the added resource utilization when deciding to perform lavage. Although the principle that dilution resolves contamination has been long accepted in surgical practice, current evidence does not substantiate this belief, particularly in the context of appendicitis. Furthermore, there is no substantial evidence supporting the effectiveness of peritoneal lavage in reducing postoperative intra-abdominal abscess incidence in pediatric patients (1,13). Importantly, this study does not aim to evaluate the efficacy of lavage in preventing postoperative complications, as no follow-up data on infection or other outcomes were collected. These findings reflect surgical practice patterns more than interventional outcomes. Interpretation should be limited to the predictors of intraoperative decisions. This study has several limitations. First, the retrospective design restricts causal inferences. Second, the absence of postoperative follow-up data, including rates of surgical site infections or intra-abdominal abscesses, limits our ability to assess the clinical impact of lavage. Third, reliance on operative notes and incomplete records may introduce bias in how intraoperative findings were interpreted. Lastly, the study lacks external validation and should be interpreted as hypothesis-generating. 71 JCTEI 72 JCTEI Table 1: Baseline characteristics and difference results between patient groups Peritoneal lavage p-value Yes (n=60; 46.5%) No (n=69; 53.5%) Gender, n (%) Female 31 (51.7) 26 (37.7) 0.078a Male 29 (48.3) 43 (62.3) Age, mean ± SD 10.67±4.03 12.86±2.76 0.002b Fever, n (%) 34 (56.7) 11 (15.9) 0.000a Vomiting, n (%) 27 (45.0) 8 (11.6) 0.000a Nausea, n (%) 12 (20.0) 5 (7.2) 0.030a Hematuria, n (%) 6 (10.0) 5 (7.2) 0.403a Leukocytosuria, n (%) 9 (15.0) 5 (7.2) 0.130a Diarrhea, n (%) 16 (26.7) 4 (5.8) 0.001a Rebound, n (%) 55 (91.7) 54 (78.3) 0.030a Distention, n (%) 10 (16.7) 20 (29.0) 0.074a Leukocyte, mean ± SD 17208.33±4783.70 12744.93±2871.80 0.000b Hemoglobin, mean ± SD 11.55±1.66 12.57±1.69 0.000b Symptom duration, mean ± SD 4.05±2.28 1.62±0.57 0.000b CRP, n (%) High 56 (93.3) 52 (75.4) 0.005a Low 4 (6.7) 17 (24.6) CT, n (%) None 50 (83.3) 67 (97.1) Acute appendicitis 3 (5.0) 2 (2.9) 0.008c Perforation 5 (8.3) - Normal 2 (3.3) - USG, n (%) None 11 (18.3) 23 (33.3) Acute appendicitis 17 (28.3) 31 (44.9) Perforation 15 (25.0) 2 (2.9) 0.001c Normal 7 (11.7) 5 (7.2) Liquid 3 (5.0) 3 (4.3) Mesenteric lymphadenitis 7 (11.7) 5 (7.2) Incision type, n (%) Transverse 47 (78.3) 69 (100.0) 0.000a Paramedian 13 (21.7) - Omentectomy, n (%) 18 (30.0) - 0.000a a. Fischer’s Exact Test, b. Mann Whitney U Test, c. Chi-Square Likelihood Ratio, SD: Standard Deviation. 73 JCTEI In their study, Kotan et al (15) evaluated cleaning with dry compresses, peritoneal lavage methods with physiological saline or Ringer's lactate, and Povidone Iodine in the surgical treatment of intra-abdominal infections on a total of 113 cases and reported that dry cleaning gave the best results. The same study reported that the length of hospital stay was higher in the peritoneal irrigation groups. In their research, Uğur et al (16) investigated the effectiveness of peritoneal lavage in gastric perforations on 40 rats and reported that it caused more adhesion than wiping with moist compresses. On the other hand, Gammeri et al (2) reported in their meta-analysis that the contribution of peritoneal lavage performed to prevent postoperative intra-abdominal abscess formation after appendectomy to intra-abdominal abscess formation in patients was not statistically significant. High-quality evidence indicates that salinebased intraoperative peritoneal lavage can prolong operative time, potentially leading to notable clinical and logistical consequences in surgical practice (1,14). Perovic (17) reported that complications were more common in children who underwent drainage after appendectomy. In our study, the fact that no postoperative infection was observed in any of the patients indicates that peritoneal washing for infection after appendectomy is an unnecessary invasive procedure, which aligns with the literature. In our opinion, apart from its use in different areas, although there are not enough studies showing its benefits after appendectomy and no guide or directive in practice, it is possible to attribute this high use of peritoneal irrigation to two possibilities. The first one is that the physician uses it for self-assurance due to the lack of sufficient tests or knowledge of accompanying diseases in emergency interventions, and the second possibility is that it may be a practice behavior that has become routine for some surgeons. Both reasons make peritoneal irrigation reasonable for preventing intra-abdominal infection and adhesion development after appendectomy. However, both clinical studies and meta-analysis results, as well as the similarity Table 2: Purulent and hospitalization duration differences between patient groups Peritoneal lavage p-value Yes (n=60; 46.5%) No (n=69; 53.5%) Purulent, n (%) 37 (61.7) - 0.000a Hospitalization duration, mean±SD 6.33±3.23 2.14±0.71 0.000b a. Fischer’s Exact Test, b. Mann Whitney U Test, SD: Standard Deviation, N/A: Not Applicable. Table 3: Spearman’s rho correlation analysis results between peritoneal lavage and significant factors Peritoneal lavage r p-value Age -0.272** 0.002 Fever 0.426** 0.000 Vomiting 0.375** 0.000 Nausea 0.188*0.033 Diarrhea 0.288** 0.001 Rebound 0.185*0.036 Leukocyte 0.492** 0.000 Hemoglobin -0.315** 0.000 Symptom duration day 0.659** 0.000 CRP -0.243** 0.006 CT 0.242** 0.006 USG 0.260** 0.003 Omentectomy 0.432** 0.000 Purulent 0.680** 0.000 Hospital duration day 0.753** 0.000 *p<0.05, **p<0.01 74 JCTEI Table 4. Binary logistic regression analysis results between peritoneal lavage and significant factors B S.E. Wald p-value OR Age -0.144 0.120 1.433 0.231 1.155 Fever 0.500 0.813 0.378 0.538 0.607 Vomiting 0.384 0.911 0.178 0.673 0.681 Nausea 0.278 1.338 0.043 0.836 0.758 Diarrhea -1.912 1.742 1.204 0.273 6.764 Rebound 1.088 1.179 0.852 0.356 0.337 Leukocyte 0.000 0.000 0.213 0.644 1.000 Hemoglobin -0.723 0.302 5.727 0.017* 2.060 Symptom duration day 1.124 0.637 3.110 0.078 0.325 CRP 0.489 0.797 0.376 0.540 0.613 CT 3.491 1.703 4,201 0.040* 0.030 USG 0.155 0.214 0.526 0.468 0.856 Purulent 18.225 6867.904 0.000 0.998 0.000 Omentectomy -5.296 25286.281 0.000 >0.05 199.501 Hospital duration day 0.955 0.532 3.217 0.073 0.385 Constant 1.779 3.985 0.199 0.655 0.169 -2 Log Likelihood Ratio: 63.761; Cox & Snell R Square: 0.588; Nagelkerke R Square: 0.786 *p<0.05 Figure 1. Correlation matrix 75 JCTEI of the rates of patients who underwent and did not undergo peritoneal irrigation in retrospective studies, as in our research, reveal that peritoneal irrigation is not necessary after appendectomy to prevent intraabdominal infection and adhesion. Another finding that supports this argument is the univariate and multivariate analysis results. In univariate analysis, all parameters necessary for appendectomy appear to affect peritoneal lavage. However, the negative correlation coefficients of many parameters suggest that peritoneal lavage is generally performed if the patient's condition is poor. From this perspective, the surgeon's anxiety affects peritoneal lavage more. The fact that only hemoglobin and CT values of all these variables were significant in the multivariate analysis results shows that the univariate parameters were evaluated incorrectly. In other words, peritoneal lavage is performed during appendectomy in patients with only one or a few clinical values considered poor. However, studies and results show that peritoneal lavage does not significantly affect intra-abdominal infection after appendectomy. Limitations Limited results were obtained because the number of patients in this study was small, and it was designed retrospectively. Apart from these two limitations, the fact that no abdominal infection was observed in the postoperative period in either group limits the ability to make analyses that reveal the factors affecting disease development. However, this limitation is also seen in other studies in the literature, and the retrospective nature of our research was decisive at this point. Again, since the study is retrospective, postoperative pain, infection management, and longitudinal follow-up data are not regular in patients; this situation was also seen in our research as one of the general limitations of retrospective studies. Conclusions This retrospective study suggests that peritoneal lavage during pediatric open appendectomy is influenced by clinical and intraoperative factors, especially low hemoglobin levels and abnormal CT findings. However, in the absence of postoperative follow-up data, no conclusions can be drawn about the effectiveness of lavage in preventing complications. The findings reflect surgical decision-making patterns rather than the outcomes of those decisions. Future prospective studies with standardized protocols and outcome monitoring are needed to determine whether peritoneal lavage has any impact on clinical recovery. Conflict of interest: The authors report no conflict of interest. Funding source: No funding was required. Ethical approval: An ethical compliance certificate was received from Yozgat Bozok University NonInterventional Clinical Research Ethics Committee, dated 08/05/2024, with decision number 2024-GOKAEK-243_2024.05.08_48. Informed consent: Given the retrospective design of the study, the requirement for informed consent for publication was waived. Acknowledgments: None Peer-review: Externally. Evaluated by independent reviewers working in at least two different institutions appointed by the field editor. Data availability: The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. Contributions Research concept and design: SUT, HI Data analysis and interpretation: SUT, HI Collection and/or assembly of data: SUT, HI, AS Writing the article: SUT, HI Critical revision of the article: SUT, HI, AS Final approval of the article: SUT, HI, AS All authors read and approved the final version of the manuscript. References 1. Zhou Q, Meng W, Ren Y, Li Q, Boermeester MA, Nthumba PM, et al. Effectiveness of intraoperative peritoneal lavage with saline in patients with intraabdominal infections: a systematic review and metaanalysis. World J Emerg Surg. 2023;18(1):24. 2. Gammeri E, Petrinic T, Bond-Smith G, Gordon-Weeks A. Meta-analysis of peritoneal lavage in appendicectomy. BJS Open. 2019;3(1):24-30. 3. Daskalopoulou D, Kankam J, Ambe P, Zarras K. Singlecenter retrospective analysis of outcomes of patients undergoing staged peritoneal lavage for secondary peritonitis. World J Surg. 2020;44(7):2185-90. 4. Sneiders D, Lambrichts D, Swank H, Blanken-Peeters C, Nienhuijs S, Govaert M, et al. Long-term follow-up of a multicentre cohort study on laparoscopic peritoneal 76 JCTEI lavage for perforated diverticulitis. Colorectal Dis. 2019;21(6):705-14. 5. Pak LM, Coit DG, Eaton AA, Allen PJ, D’Angelica MI, DeMatteo RP, et al. Percutaneous peritoneal lavage for the rapid staging of gastric and pancreatic cancer. Ann Surg Oncol. 2017;24(5):1174-9. 6. Parisi A, Gemini A, Desiderio J, Petrina A, Trastulli S, Grassi V, et al. Laparoscopic peritoneal lavage: our experience and review of the literature. Videosurgery Miniinv. 2016;11(2):83-7. 7. Feng C, Su X, Zhou X, Wang LL, Li B, Chen L, et al. Early peritoneal lavage with ulinastatin improves outcome and enhances multi-organ protection in a model of severe acute pancreatitis. Exp Ther Med. 2015;9(4):11717. 8. Gow KW, Haley LP, Phang PT. Validity of visual inspection of diagnostic peritoneal lavage fluid. Can J Surg. 1996;39(2):114-6. 9. Zhu C, Zhang S, Zhong H, Gu Z, Kang Y, Pan C, et al. Intra-abdominal infection in acute pancreatitis in eastern China: microbiological features and a prediction model. Ann Transl Med. 2021;9(6):489. 10. Silva-Nunes J, Cardoso T. Intra-abdominal infections: the role of different classifications on the selection of the best antibiotic treatment. BMC Infect Dis. 2019;19(1):980. 11. Sartelli M, Catena F, Abu-Zidan FM, Ansaloni L, Biffl WL, Boermeester MA, et al. Management of intraabdominal infections: recommendations by the WSES 2016 consensus conference. World J Emerg Surg. 2017;12:29. 12. Bi LW, Yan BL, Yang QY, Cui HL. Peritoneal irrigation vs suction alone during pediatric appendectomy for perforated appendicitis: a meta-analysis. Medicine (Baltimore). 2019;98(50):e18047. 13. Abu A, Mohamedahmed AY, Alamin A, Mohamed M, Osman M, Mohammed MJ, et al. Evaluation of drain insertion after appendicectomy for complicated appendicitis: a systematic review and meta-analysis. Cureus. 2022;14(11):e31831. 14. Iglesias NJ, Arrowood R, Montgomery L, Leeper E, Tsao KJ, Iglesias JL. Operative time is independently associated with morbidity in pediatric complicated appendicitis. J Surg Res. 2022;276:143-50. 15. Kotan C, Karaayvaz M, Daşdemir I, Barut I, Özgören E. Effectiveness of peritoneal dry cleaning method in surgical treatment of intra-abdominal infections. Van Tıp Derg. 1999;6(2):22-5. 16. Uğur M, Koca YS, Çetin R. Effects of intraoperative peritoneal cleansing methods on peritoneal adhesion in gastric perforations. Turk J Surg. 2012;28(1):21-5. 17. Perović Z. Drainage of the abdominal cavity and complications in perforating appendicitis in children. Med Pregl. 2000;53(3-4):193-6. Publisher's Note: Unico's Medicine remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.