Background

The management of the oxygenator can be prolonged in the long-term procedures especially during extracorporeal membrane oxygenation (ECMO) for bridge to transplant or bridge to recovery. Long-term use often involves an overrun of the time of use with respect to certification of the oxygenating module of 14 days, for the maintenance of performance and efficiency of the oxygenator. The evaluation of the long-term oxygenator efficiency is complex and depends on the: patient pathology, ECMO configuration, the management of coagulation and anticoagulation, materials selection and circuit components, the structure, design and performance of the oxygenator. In this context we investgated the long-term performance of the A.L.ONE Eurosets ECMO oxygenator in relation to the parameters prodromal to replacement.

Methods

We retrospectively collected eight years data from Anthea Hospital GVM Care & Research, Bari, Italy on the long-term use exceeding 14 days of Eurosets A.L.ONE ECMO Adult oxygenator in Polymetylpentene fiber, for ECMO procedures, including the procedures: Veno Arterial (VA) ECMO post-cardiotomy or not, veno-venous (VV) ECMO. The primary end points were the evaluation of Gas Transfer: oxygen partial pressure (PO₂) post oxygenator, Carbon dioxide partial pressure (PCO₂) post oxygenator, the oxygen transfer across the oxygenator membrane V′O₂, differential CO₂ content across oxygenator; Pressure monitoring: oxygenator pressure Drop in relation to Blood flow rate (BFR) (ΔP); Hematologic values: Hemoglobin, Fibrinogen, Platelets, aPTT, D-Dimer, LDH.

Results

Nine VA ECMO patients who used the oxygenator for 18.5 days and two VV ECMO patients who used the oxygenators for 17.2 days on the seventeenth days reported average values PaO₂ (267 ± 29 mmHg); PaCO₂ (34 ± 4 mmHg) with gas blender values set to 3.8 ± 0.6 L/min of air and a FiO₂ of 78 ± 5%; the transfer across the oxygenator membrane V′O₂ was 189 ± 43 (ml/min/m²). The mean peak of partial pressure of carbon dioxide from the gas exhaust of oxygenator (P_ECO₂) was 38 ± 4 mmHg; differential CO₂ across the oxygenator “pre-oxygenator PCO₂–post-oxygenator PCO₂” (18 ± 6 mmHg); the mean blood flow rate (BFR) 4.5 ± 0.6 (L/minute); the pump revolution per minutes mean maximum rate was 4254 ± 345 (RPM); the mean pressure drop (ΔP) was 76 ± 12 mmHg; the mean peak of d-dimers (DDs) was 23.6 ± 0.8 mg / dL; the mean peak of LDH was 230 ± 55 (mg/dl); fibrinogen mean peak 223 ± 40 (mg/dl).

Conclusions

The performance of the Eurosets A.L.ONE ECMO Adult polymethylpentene fiber oxygenator in our experience has proven efficiency in terms of O₂ uptake and CO₂ removal, blood fluid dynamics, metabolic compensation and heat exchange in the long-term treatment. The device was safe without iatrogenic problems over a period of 14 days in the patients undergoing ECMO VA and in all patients undergoing VV ECMO with continuous administration of anticoagulation therapy.