Classification and discrimination of pediatric patients undergoing open heart surgery with and without methylprednisolone treatment by cytomics
Abstract
Methylprednisolone (MP) is frequently preoperatively administered in children undergoing open heart surgery. The aim of this medication is to inhibit overshooting immune responses.
Earlier studies demonstrated cellular and humoral immunological changes in pediatric patients undergoing heart surgeries with and without MP administration. Here in a retrospective study we investigated the modulation of the cellular immune response by MP.
The aim was to identify suitable parameters characterizing MP effects by cluster analysis. Blood samples were analysed from two aged matched groups with surgical correction of septum defects.
Group without MP treatment consisted of 10 patients; MP was administered on 21 patients (median dose: 11mg/kg) before cardiopulmonary bypass (CPB). EDTA anticoagulated blood was obtained 24 h preoperatively, after anesthesia, at CPB begin and end (CPB2), 4h, 24h, 48h after surgery, at discharge and at out-patient follow-up (8.2; 3.3-12.2 month after surgery; median and IQR).
Flow cytometry showed the biggest MP relevant changes at CPB2 and 4h postoperatively. They were used for clustering analysis.
Classification was made by discriminant analysis and cluster analysis by means of Genes@work software. 146 parameters were obtained from analysis. Cross-validation revealed several parameters being able to discriminate between MP groups and to identify immune modulation.
MP administration resulted in a delayed activation of monocytes, increased ratio of neutrophils, reduced T-lymphocytes counts. Cluster analysis demonstrated that classification of patients is possible based on the identified cytomics parameters.
Further investigation of these parameters might help to understand the MP effects in pediatric open heart surgery