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The comments written by R. Otter et al. [...]

Care management of newborns in the neonatal intensive care unit (NICU) requires numerous PVC (PolyVinyl Chloride) medical devices (MD) containing plasticizers that can migrate and contaminate the patient. We measured the magnitude of neonates’ exposure to plasticizers (di-ethylhexylphthalate (DEHP) and alternatives) in relation to urinary concentrations of their metabolites. Plasticizers’ exposure was evaluated (1) by calculating the amounts of plasticizers prone to be released from each MD used for care management, and (2) by measuring the patients’ urinary levels of each plasticizers’ metabolites. 104 neonates were enrolled. They were exposed to di-isononylphthalate (DINP), especially via transfusion and infusion MD, and to DEHP via ECMO (Extra Corporeal Membrane Oxygenation) and respiratory assistance MD. Mean exposure doses exceeded the derived no-effect level of DINP and DEHP by a 10-fold and a 1000-fold factor. No PVC MD were plasticized with di-isononylcyclohexane-1,2-dicarboxylate (DINCH). High urinary concentrations of DEHP metabolites were directly correlated with DEHP exposure through ECMO MD. Urinary concentrations of DINP metabolites in transfused patients were also high. DINCH metabolites were found in urine, suggesting another route of exposure. Neonates in NICU are considerably exposed to plasticizers, with magnitudes varying with the type of MD used. The high exposure to DEHP and DINP leads to a risk of their metabolites’ toxicity.

Infusion medical devices (MDs) used in hospitals are often made of plasticized polyvinylchloride (PVC). These plasticizers may leach out into infused solutions during clinical practice, especially during risk-situations, e.g multiple infusions in Intensive Care Units and thus may enter into contact with the patients. The migrability of the plasticizers is dependent of several clinical parameters such as temperature, contact time, nature of the simulant, etc… However, no data is available about the influence of the flow rate at which drug solutions are administrated. In this study, we evaluated the impact of different flow rates on the release of the different plasticizers during an infusion procedure in order to assess if they could expose the patients to more toxic amounts of plasticizers. Migration assays with different PVC infusion sets and extension lines were performed with different flow rates that are used in clinical practice during 1h, 2h, 4h, 8h and 24h, using a lipophilic drug simulant. From a clinical point of view, the results showed that, regardless of the plasticizer, the faster the flow rate, the higher the infused volume and the higher the quantities of plasticizers released, both from infusion sets and extension lines, leading to higher patient exposure. However, physically, there was no significant difference of the migration kinetics linked to the flow rate for a same medical device, reflecting complex interactions between the PVC matrix and the simulant. The migration was especially dependent on the nature and the composition of the medical device.

Background: ECMO is a therapeutic act with a high risk of exposure to diethylhexylphthalate (DEHP), plasticizer from PVC tubings. The replacement of this plasticizer with alternative compounds is recommended but the risks associated with the use of new plasticizers have not been evaluated in ECMO situations. Methods: Ex vivo ECMO models were performed with different flow rates over 6 days to evaluate the migration of plasticizers and their potential toxic risk for patient. The release of plasticizers during ECMO was measured and compared to reference value (derived no effect level, DNEL) and to cytotoxic concentration carried out with MTT test. Results: Trioctyltrimellitate (TOTM), main plasticizer present in circuit (44% w/w), is weakly released during ECMO. Concentrations are not cytotoxic and exposure doses are lower than DNEL. In contrast, DEHP doses are higher than the DNEL despite a lower presence of DEHP in the circuit (0.2%). We have shown that DEHP is not coming from the circuit but from the priming bag. Replacing this bag with a multilayer one avoids the exposure to DEHP. Conclusion: Our study shows that circuits made of PVC plasticized with TOTM against DEHP improves the safety of ECMO. [ABSTRACT FROM AUTHOR]