Prevalence and Clinical Implications of Heightened Plastic Chemical Exposure in Pediatric Patients Undergoing Cardiopulmonary Bypass

Abstract

AbstractImportancePhthalate chemicals are used to manufacture disposable plastic medical products, including blood storage bags and components of cardiopulmonary bypass (CPB) circuits. During cardiac surgery, patients can be inadvertently exposed to phthalate chemicals that are released from these plastic products.ObjectiveTo quantify iatrogenic phthalate chemical exposure in pediatric patients undergoing cardiac surgery, and examine the link between phthalate exposure and post-operative outcomes.Design, Setting, and ParticipantsThe study cohort included 122 pediatric patients undergoing cardiac surgery at Children’s National Hospital. For each patient, a single plasma sample was collected pre-operatively and two additional samples were collected post-operatively upon return from the operating room (post-operative day 0) and the morning after surgery (post-operative day 1).ExposuresConcentrations of di(2-ethylhexyl)phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry.Main Outcomes and MeasuresPlasma concentrations of phthalates, post-operative blood gas measurements, and post-operative complications.ResultsStudy subjects were subdivided into three groups, according to surgical procedure: 1) cardiac surgery not requiring CPB support, 2) cardiac surgery requiring CPB with crystalloid prime, and 3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience post-operative complications, including arrhythmias, low cardiac output syndrome, and additional post-operative interventions. RBC washing was an effective strategy to reduce DEHP levels in CPB prime.Conclusions and RelevancePediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.Key PointsQuestionIs cardiac surgery with cardiopulmonary bypass a significant source of phthalate chemical exposure in pediatric patients?FindingsIn this study of 122 pediatric cardiac surgery patients, phthalate metabolites were quantified from blood samples before and after surgery. Phthalate concentrations were highest in patients undergoing cardiopulmonary bypass with red blood cell-based prime. Heightened phthalate exposure was associated with post-operative complications.MeaningCardiopulmonary bypass is a significant source of phthalate chemical exposure, and patients with heightened exposure may be at greater risk for postoperative cardiovascular complications.Graphical AbstractPediatric cardiac surgery patients undergoing cardiopulmonary bypass are exposed to phthalate plasticizers through contact with plastic medical devices manufactured with DEHP (indicated with blue outline), including blood product and crystalloid solution storage bags, tubing, cannulas, and reservoirs. The leached DEHP chemical (indicated with blue circles) can localize to the heart, where it can contribute to post-operative complications. DEHP: Di(2-ethylhexyl)phthalate, ET: endotracheal tube, FFP: fresh frozen plasma, RBCs: red blood cells.