Severity classification and risk factors of seroma after transabdominal preperitoneal hernia repair

This study aimed to develop a classification to precisely describe seroma following transabdominal preperitoneal hernia repair (TAPP) as well as identify risk factors and create a prediction model for seroma development.

Postoperative seroma was classified into grades 0-IV, with grades ≥ II defined as the seroma group (S group: 265 cases), which was compared with the normal course group (N group: 1,279 cases) to determine risk factors using logistic regression analysis. A prediction model was developed based on these independent predictors. Receiver operating characteristic (ROC) curve analysis was conducted to assess the discriminability and calibrability of the model. Additionally, a model to validate the incidence of seroma was used for risk stratification.

This classification revealed grades 0, I, II, III, and IV in 1,194 (70.9%), 85 (5.5%), 236 (15.3%), 12 (0.8%), and 17 (1.1%) patients, respectively. Multivariate analysis revealed risk factors for seroma formation, including age of > 66 years, American Society of Anesthesiologists scores of ≥ 2, surgery for recurrent hernia, size of hernia defect of > 3 cm, and duration of sickness of > 1 year. The prediction model demonstrated the rates of seroma in the low, moderate, and high score groups of 10.5% (103/984), 23.7% (99/417), and 44.1% (63/143), respectively.

A postoperative complication of TAPP was proposed as a severity classification of seroma. A model to predict the seroma was developed based on the identified risk factors, thereby confirming the possibility of preoperative prediction of the seroma.