29, 37, 28
The ELSO 50 mg/dL threshold is a definition of an event, not a level below which nothing is happening. A rising free haemoglobin inside the 11-50 mg/dL band with concordant markers justifies looking for a cause and raising neurological surveillance, not a circuit change.
No low-level haemolysis (free haemoglobin below 11 mg/dL)
Saeed O, Jakobleff WA, Forest SJ, et al. Ann Thorac Surg 2019;108(3):756-763. DOI 10.1016/j.athoracsur.2019.03.030
Low-level haemolysis defined as 48-hour plasma free haemoglobin of 11 to 50 mg/dL
Single centre, retrospective, VA only. Causation not established: haemolysis may mark a thrombogenic circuit rather than cause the strokes. No interventional data.
62 of 150 (41 percent) met the definition. Non-haemorrhagic stroke in 20 of 62 (32 percent) versus 4 of 88 (5 percent); adjusted HR 7.6 (2.2 to 25.9, p=0.001). Graded: 26-50 mg/dL HR 11.3 (3.6 to 35.1); 11-25 mg/dL HR 4.4 (1.36 to 14.85). Two-fold greater rise in mean platelet volume (0.98 plus or minus 1.1 versus 0.49 plus or minus 0.96 fL, p=0.03). Operative mortality with stroke 83 versus 45 percent.
150 adults on venoarterial ECMO at a single centre over almost six years; mean age 55 plus or minus 14; 33 percent women