 A blood sample and reagents are placed into a small cup. A pin suspended from a wire is immersed into the sample. The pin rotates back and forth at a fixed angle. The movement of the pin is optically monitored and converted into a real time measurement that is represented graphically. Prior to clot formation, pin rotation is unhindered and is graphically represented as a straight line. As the subjects blood sample starts to clot, strands of clot form between the pin and the cup wall, restricting the movement of the pin depending on the strength of the clot. Graphically, this is represented as a symmetrical widening of the curve. Blood will be obtained for ROTEM fibrinogen levels from each subject seven times during their hospital admission: once within 24 hours of burn injury day 1, and on days 2, 3, 5, 7, 14 and 21. For each sample, 5.4 mL of whole blood will be collected into 2 citrated tubes 2.7 mL in each tube. For all subjects, both pediatric and adult, blood will be collected via an indwelling catheter arterial or central line. One 2.7 ml tube will be used for ROTEM analysis. The amount of blood is in accordance with the acceptable limit of ROTEM analysis. ROTEM testing will be performed according to the manufacturers instructions using test kit reagents. Members of the clinical research team who have been trained and certified to use the ROTEM device will perform the appropriate ROTEM tests. The second 2.7 mL citrated tube will be used to measure fibrinogen level, using the automated central laboratory device in hospital. 