Biomarker Measurements
Samples of blood were collected at six points in time: T0- anesthesia induction; T1- lowest core temperature (only collected in elective patients with core temperature ≤32°C, n=14); T2- just before protamine administration; T3- end of surgery; T4- 24h after surgery; T5- 96-120h after surgery. A central venous line was used for samples collected at T0, T4, and T5. A circuit from the cardiopulmonary bypass machine was used for samples collected at T1 and T2. A radial artery line was used for the samples collected at T3.
All samples were analyzed at the Dept. of Clinical Chemistry, Division of Laboratory Medicine, Skåne University Hospital, Lund, Sweden, on a ROTEM. Parameters tested were INTEM, EXTEM, HEPTEM, and FIBTEM and variables clotting time (CT), which is time from start until clotting is initiated in seconds (s) and maximum clot firmness (MCF), which is maximum diameter of clot in millimeters (mm).