Which delivery method described uses a cotton ball on a cone covering the animal's snout?

Which delivery method described uses a cotton ball on a cone covering the animal's snout?

• A. Open drop system
• B. Endotracheal intubation
• C. Rebreathing
• D. Non-rebreathing

Answer: (A)

Open drop anesthesia uses a cotton ball saturated with volatile anesthetic placed on a cone over the animal’s snout, so the vapors rise and the animal inhales them directly. That exact setup—cotton ball on a cone near the nose—is the hallmark of this method, making it the best fit for the description. This is different from delivering anesthesia through an endotracheal tube, which involves placing a tube into the airway for controlled gas delivery. It’s also distinct from rebreathing or non-rebreathing circuits, which are closed or semi-closed systems with tubing, reservoirs, and often scavenging; those rely on a controlled gas flow and a circuit rather than a simple cotton ball and cone near the nose.

Open drop anesthesia uses a cotton ball saturated with volatile anesthetic placed on a cone over the animal’s snout, so the vapors rise and the animal inhales them directly. That exact setup—cotton ball on a cone near the nose—is the hallmark of this method, making it the best fit for the description.

This is different from delivering anesthesia through an endotracheal tube, which involves placing a tube into the airway for controlled gas delivery. It’s also distinct from rebreathing or non-rebreathing circuits, which are closed or semi-closed systems with tubing, reservoirs, and often scavenging; those rely on a controlled gas flow and a circuit rather than a simple cotton ball and cone near the nose.