1. From the Hedenstierna Laboratory, Department of Surgical Sciences (M.K., A.K., J.B.B., A.L., T.S.), and Clinical Physiology, Department of Medical Sciences (G.H.), Uppsala University, Uppsala, Sweden; Department of Anesthesiology and Intensive Care Medicine, Otto von Guericke University Magdeburg, Magdeburg, Germany (M.K., A.K., T.H., T.S.); Oscillogy LLC, Pittsburgh, Pennsylvania (J.E.B.); and D