29, 55, 32
Do not lower blood flow to treat a haemolysis number. Look at inlet pressure, drainage, transmembrane gradient and any circuit-connected CRRT instead. The CRRT association is actionable and easily overlooked.
Within-cohort regression on circuit and patient variables
Costantini S, Belliato M, Ferrari F, Gazzaniga G, Ravasi M, Manera M, De Piero ME, Curcelli A, Cardinale A, Lorusso R. Perfusion 2022;38(3):609-621. DOI 10.1177/02676591211073768
Daily plasma free haemoglobin and haptoglobin examined against patient characteristics, daily laboratory findings and circuit variables
35 patients, retrospective, single centre. The flow finding is most easily read as confounding by indication: flow falls because something is wrong, and that something is haemolysing the blood.
A reduction in ECMO blood flow of 1 L/min was associated with a daily haptoglobin consumption of 93.371 mg/dL (p=0.001) — lower flow tracked with MORE haemolysis. Membrane oxygenator dead space was associated with haptoglobin reduction (B = minus 215.307, p=0.004). CRRT connected to the ECMO circuit was associated with both higher daily free haemoglobin and lower haptoglobin.
35 consecutive adult venovenous ECMO patients at a single centre over almost six years