1. 1Department of Anesthesiology, University of Washington, Seattle, Washington.
2. 2Department of Anesthesiology, University of Washington, Seattle, Washington.
3. 3Department of Anesthesiology, University of Washington, Seattle, Washington.
4. 4Department of Anesthesiology, University of Washington, Seattle, Washington.
5. 5Department of Anesthesiology and Perioperative Care, University of California-Irvine, Irvine, California; Department of Anesthesiology, University of Washington, Seattle, Washington.
6. 6Department of Anesthesiology, University of Washington, Seattle, Washington.