A Comparative Study to Evaluate the Accuracy and Safety of the GlySure Continuous Intravascular Glucose Monitoring System Versus Intermittent Blood Glucose Monitoring

Inclusion Criteria: 1. Patient or legal representative MUST be willing to sign an informed consent document 2. Male and female aged 18 years and above 3. Require Central Venous Catheter (CVC) into the right internal Jugular vein as part of disease management and treatment 4. Expected to remain in the Surgical Intensive Care Unit (SICU) for at least 30 hours and up to 7 days- Exclusion Criteria: 1. Patient or legal representative unable to provide written informed consent 2. Patient who is pregnant 3. Patient who is currently being administered Mannitol 4. Patient with history of Pulmonary Embolism (PE) 5. Patient with history of thrombosis 6. Patient with known hyper-coagulation 7. Patient with known history of heparin hypersensitivity 8. Patient with history of heparin induced thrombocytopenia 9. Participation in a clinical study involving an unlicensed pharmaceutical product and/or device within the 3 months prior to enrolment in this study 10. Patient with known hypersensitivity/allergy to adhesive I.V. dressings such as 3M Tegaderm film 11. Patient likely to require an MRI scan during their stay in the SICU 12. Patients likely to require treatment with Mannitol during time in the SICU