Evaluation of Food Withholding Time on Propofol Total Intravenous Anesthesia in Sheep

Objective- Evaluation of the effect of different fasting times on the quality of propofol total intravenous anesthesia (TIVA) and recovery features. Design- Experimental prospective design. Animals- Fifteen lambs. Procedures- Fifteen lambs that anesthetized for carotid translocation surgery were included in this current study and allocated in to three groups randomly. In Group 1, food was withheld for 24 hours, with free access to the water. In Group 2 and 3 the food withhold time was 48 and 72 hours. In all animals the anaesthesia were induced by propofol (5 mg/kg) and maintained by continuous propofol infusion 0.41-0.45 mg/kg/hr for 60 minutes. Heart rate (HR) and respiratory rate (RR), rectal temperature (Temp) and invasive systolic (SAP), diastolic (DAP) and mean arterial pressure (MAP) were measured during anaesthesia. Time to first swallowing attempt, time to lift the head and time to standing were recorded by videoing the animals. Results- Although the longest recovery times were recorded in group 3 but no significant difference were recorded between groups under study in all measured parameters. The only significant finding was the number of animals that were regurgitated during anaesthesia that was significantly higher in group 3. Conclusion and Clinical Relevance- Long food withdrawal could not alter different recovery times but regarding to higher regurgitation in group three and lower quality of anaesthesia in this group it seems that the best results were in group one.