1. Department of Anaesthetics, Letterkenny University Hospital, Letterkenny, Ireland
2. Tallaght University Hospital, Dublin, Ireland
3. Department of Surgery, Tallaght University Hospital, Dublin, Ireland
4. Department of Statistics, University of Limerick, Limerick, Ireland
5. Department of Anaesthetics, Tallaght University Hospital, Dublin, Ireland
6. Department of Medicine, Tallaght University Hospital, Dublin, Ireland
7. Department of Orthopaedics, Tallaght University Hospital, Dublin, Ireland