Veterinary Anesthesia exam questions: topics, study tips and free sample questions

Answer: E. Leakage of air around the endotracheal tube at 20 cm H20 helps to ensure that the cuff is not over-inflated or under-inflated during anesthesia. Remember that the muscles will continue to relax as a deeper plane of anesthesia is achieved, and the cuff should be retested at that time. lf the cuff is over-inflated, pressure necrosis or tearing of the trachea can occur. If the cuff is under-inflated, there is increased exposure of the surgical team to waste anesthetic gasses, and it may be more difficult to keep the patient anesthetized. The American Animal Hospital Association (AAHA) provides this info on Equipment Preparation prior to an anesthetic event.

Answer: A. A Bain anesthetic circuit run at a high flow rate of 200-300 ml/kg/min will not allow rebreathing of exhaled gasses. Remember that a Bain system is like a tube within a tube. New oxygen and anesthetic gas is inhaled down the inner tube, and exhaled gas exits through the outer tube. At flow rates of 130-200 ml/kg/min or less the Bain functions as a partial rebreathing system, and the animal rebreathes some of the exhaled gasses Semi-closed and partial rebreathing systems are the same thing. They run at intermediate flow rates where fresh gas is delivered in excess of metabolic consumption, from about 10 ml/kg/min (large animals) or 30 ml/kg/min (small animals). A closed anesthetic rebreathing system only provides enough fresh gas flow to meet an animal's metabolic needs, about 5-10 ml/kg/min (depending on animal size. Flow is lower for larger animals and higher for smaller animals).

Answer: B. Opened vials of propofol should be discarded after 6 hours or they may support bacterial growth. You CAN mix 1%propofol with 2.5% thiopental as an induction agent. Propofol is RAPIDLY cleared, and is NOT particularly irritating to tissues if it goes outside the vein accidentally. ( UNlike thiopental, which is VERY irritating if it goes peri-vascular).