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Randomized Controlled Trial
. 2024 Mar;45(3):322-328.
doi: 10.1017/ice.2023.214. Epub 2023 Nov 6.

Delayed versus primary closure to minimize risk of surgical-site infection for complicated appendicitis: A secondary analysis of a randomized trial using counterfactual prediction modeling

Amarit Tansawet  1   2 , Boonying Siribumrungwong #  3 , Suphakarn Techapongsatorn  1 , Pawin Numthavaj  2 , Napaphat Poprom  4 , Gareth J McKay  5 , John Attia  6 , Ammarin Thakkinstian #  2
Affiliations
Randomized Controlled Trial

Delayed versus primary closure to minimize risk of surgical-site infection for complicated appendicitis: A secondary analysis of a randomized trial using counterfactual prediction modeling

Amarit Tansawet et al. Infect Control Hosp Epidemiol. 2024 Mar.

Abstract

Objective: To evaluate the risk of surgical site infection (SSI) following complicated appendectomy in individual patients receiving delayed primary closure (DPC) versus primary closure (PC) after adjustment for individual risk factors.

Design: Secondary analysis of randomized controlled trial (RCT) with prediction model.

Setting: Referral centers across Thailand.

Participants: Adult patients who underwent appendectomy via a lower-right-quadrant abdominal incision due to complicated appendicitis.

Methods: A secondary analysis of a published RCT was performed applying a counterfactual prediction model considering interventions (PC vs DPC) and other significant predictors. A multivariable logistic regression was applied, and a likelihood-ratio test was used to select significant predictors to retain in a final model. Factual versus counterfactual SSI risks for individual patients along with individual treatment effect (iTE) were estimated.

Results: In total, 546 patients (271 PC vs 275 DPC) were included in the analysis. The individualized prediction model consisted of allocated intervention, diabetes, type of complicated appendicitis, fecal contamination, and incision length. The iTE varied between 0.4% and 7% for PC compared to DPC; ∼38.1% of patients would have ≥2.1% lower SSI risk following PC compared to DPC. The greatest risk reduction was identified in diabetes with ruptured appendicitis, fecal contamination, and incision length of 10 cm, where SSI risks were 47.1% and 54.1% for PC and DPC, respectively.

Conclusions: In this secondary analysis, we found that most patients benefited from early PC versus DPC. Findings may be used to inform SSI prevention strategies for patients with complicated appendicitis.

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Conflict of interest statement

All authors report no conflicts of interest relevant to this article.

Figures

Figure 1.
Figure 1.
Flow diagram of enrollment and analysis.
Figure 2.
Figure 2.
Distribution of individual treatment effect of primary wound closure versus delayed primary wound closure.
See this image and copyright information in PMC

References

    1. Ferris M, Quan S, Kaplan BS, et al. The global incidence of appendicitis: a systematic review of population-based studies. Ann Surg 2017;266:237–241. - PubMed
    1. Danwang C, Bigna JJ, Tochie JN, et al. Global incidence of surgical site infection after appendectomy: a systematic review and meta-analysis. BMJ Open 2020;10:e034266. - PMC - PubMed
    1. Siribumrungwong B, Noorit P, Wilasrusmee C, Thakkinstian A. A systematic review and meta-analysis of randomised controlled trials of delayed primary wound closure in contaminated abdominal wounds. World J Emerg Surg 2014;9:49. - PMC - PubMed
    1. Jenks PJ, Laurent M, McQuarry S, Watkins R. Clinical and economic burden of surgical-site infection (SSI) and predicted financial consequences of elimination of SSI from an English hospital. J Hosp Infect 2014;86:24–33. - PubMed
    1. Badia JM, Casey AL, Petrosillo N, Hudson PM, Mitchell SA, Crosby C. Impact of surgical site infection on healthcare costs and patient outcomes: a systematic review in six European countries. J Hosp Infect 2017;96:1–15. - PubMed

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