If a lower vapor pressure agent is added to a vaporizer designed for a higher vapor pressure agent, the concentration delivered will be ______ than the setting.

When a vaporizer is designed to deliver a specific anesthetic agent, it is calibrated for the vapor pressure of that agent. Vapor pressure is a measure of a substance's ability to evaporate and subsequently exert a pressure in the vapor phase. Higher vapor pressure indicates that the agent evaporates more readily, which allows for a higher concentration of the anesthetic to be delivered.

When a lower vapor pressure agent is introduced into a vaporizer that is set for a higher vapor pressure anesthetic, the overall delivery concentration will be affected. Since the lower vapor pressure agent does not evaporate as readily, it produces less of its vapor compared to what the vaporizer setting prescribes. Consequently, the concentration of the agent delivered to the patient will be less than what the vaporizer setting indicates.

This phenomenon leads to a situation where, despite the vaporizer being set to a specific concentration, the actual concentration delivered to the patient will be lower than intended due to the properties of the lower vapor pressure agent.