1 Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, UK; Department of Anesthesiology, Nippon Medical School, Tokyo, Japan.
2 Department of Anesthesiology, Nippon Medical School, Tokyo, Japan.
3 Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Imperial College London, Chelsea and Westminster Hospital, London SW10 9NH, UK. Electronic address: d.ma@imperial.ac.uk.