1 Department of Anaesthesia and Perioperative Medicine, Auckland City Hospital, Auckland 1023, New Zealand; Department of Anaesthesia, University of Auckland, Auckland, New Zealand. Electronic address: tims@adhb.govt.nz.
2 Department of Anaesthesia and Pain Management, Royal Melbourne Hospital, Melbourne, VIC, Australia; Perioperative and Pain Medicine Unit, University of Melbourne, Melbourne, VIC, Australia; Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, VIC, Australia.
3 Department of Anaesthesia and Perioperative Medicine, Auckland City Hospital, Auckland 1023, New Zealand; Department of Anaesthesia, University of Auckland, Auckland, New Zealand.
4 Department of Medicine, University of Otago, Christchurch, New Zealand; Department of Psychiatry, University of Otago, Christchurch, New Zealand.
5 Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China.
6 Department of Anaesthesia and Perioperative Medicine, Alfred Hospital, Melbourne, VIC, Australia; Department of Anaesthesia and Perioperative Medicine, Monash University, Melbourne, VIC, Australia.