Introduction: Oxygenator exchange during extracorporeal membrane oxygenation (ECMO) is a life-threatening procedure. D-dimer has been used to predict oxygenator failure, but it is a parameter used a few days before oxygenator exchange. This study investigated parameters before and immediately after ECMO initiation that predict oxygenator exchange.
Methods: This was a single-center, retrospective study of 28 patients who received veno-venous ECMO with heparin/silicone-coated polypropylene oxygenator (NSH-R HPO-23WH-C; Senko Medical Inc., Tokyo, Japan), due to acute respiratory failure, from April 2015 to March 2020. Clinical data before ECMO initiation and during the first 3 days on ECMO were compared between the patients with oxygenator exchange (exchange group) and those without oxygenator exchange (non-exchange group).
Results: Nine (32%) patients required oxygenator exchange. The exchange group had significantly higher white blood cell count (WBC) (16,944 ± 2423/µL vs 10,342 ± 1442/µL, p < 0.05) and Acute Physiology and Chronic Health Evaluation (APACHE) II score (31 ± 5 vs 25 ± 8, p < 0.05) before ECMO initiation than the non-exchange group. The partial pressure of oxygen at the outlet of the oxygenator (PO2 outlet) and activated partial thromboplastin time (aPTT) during the first 3 days on ECMO were significantly lower in the exchange group than in the non-exchange group.
Conclusions: High WBC and APACHE II score before ECMO initiation, low PO2 outlet, and aPTT during the first 3 days on ECMO were associated with oxygenator exchange during veno-venous ECMO. These parameters could be used to avoid unexpected oxygenator exchange.
Keywords: Extracorporeal membrane oxygenation; oxygenator exchange; oxygenators; white blood cell.