Which drug is most associated with vasodilation and heat loss, contributing to hypothermia during anesthesia?

Which drug is most associated with vasodilation and heat loss, contributing to hypothermia during anesthesia?

• A. Fentanyl
• B. Midazolam
• C. Ketamine
• D. Propofol

Answer: (D)

Propofol is known for causing significant peripheral vasodilation and a drop in systemic vascular resistance. This makes heat rush from the core to the skin, a redistribution that lowers core temperature quickly after induction. At the same time, propofol blunts the body's thermoregulatory responses and reduces metabolic heat production, which compounds the cooling effect. Clinically, this combination makes hypothermia a common concern during anesthesia unless active warming measures are used. Other common anesthetics can cause some vasodilation, but their impact on core temperature is not as pronounced. Ketamine tends to preserve or even raise temperature due to its sympathetic effects, while fentanyl and midazolam produce milder vasodilation with less effect on heat loss. The strong, rapid vasodilation and impaired heat retention with propofol make it the most closely linked to hypothermia in this context.

Propofol is known for causing significant peripheral vasodilation and a drop in systemic vascular resistance. This makes heat rush from the core to the skin, a redistribution that lowers core temperature quickly after induction. At the same time, propofol blunts the body's thermoregulatory responses and reduces metabolic heat production, which compounds the cooling effect. Clinically, this combination makes hypothermia a common concern during anesthesia unless active warming measures are used.

Other common anesthetics can cause some vasodilation, but their impact on core temperature is not as pronounced. Ketamine tends to preserve or even raise temperature due to its sympathetic effects, while fentanyl and midazolam produce milder vasodilation with less effect on heat loss. The strong, rapid vasodilation and impaired heat retention with propofol make it the most closely linked to hypothermia in this context.