Volatile Anaesthesia and Perioperative Outcomes Related to Cancer (VAPOR-C): A Feasibility Study

Adult patients scheduled for elective major cancer surgery (breast, lung, prostate, melanoma, colorectal, other), expecting to last 2 or more hours and anticipated to require a minimum of one day in-hospital stay after surgery will be screened for eligibility. Recruited patients will be block randomised by cancer type to receive either volatile anaesthesia or propofol anaesthesia. . Clinicians will deliver propofol via weight-based technique (mg/kg/hour) or via target controlled infusion models (TCI; µg/ml effect or plasma concentration) or titrate volatile anaesthesia at a minimum alveolar concentration (MAC) to attain BIS values in the range of 40-60. FiO2 will be maintained at 40% following induction and the admixture with air titrated to maintain SpO2 >95%. The volatile anaesthetics to be used in this study are Sevoflurane, Isoflurane and Desflurane. They are all volatile anaesthetics approved for clinical use in Australia and used routinely for induction and maintenance of anaesthesia. Volatile anaesthetic dose is titrated by the treating anaesthetist in response to level of sedation, heart rate, respiratory rate, blood pressure and Bispectoral index monitoring, using a vaporiser connected to an anaesthetic circuit. Anaesthetists are trained to use both intravenous and inhaled anaesthetic techniques. The decision to use one technique over another is based on multitude of patient, anaesthetic and surgical factors. These include, but are not limited to: patient preference, allergy or contraindication to an agent, history of severe postoperative nausea and vomiting, medical status of patient at time of surgery, availability of equipment to perform TIVA, preference of treating anaesthetist, type, duration and location of surgery. The treating anaesthetist makes an educated decision on which anaesthetic to use for every patient guided by his or her experience and specialist anaesthetic training.