Final Answer:
The two mechanisms of heat loss that account for approximately 90% of body heat loss in the operating room are D) Evaporation and convection.
Step-by-step explanation:
In the operating room, the body primarily loses heat through evaporation and convection. Evaporation accounts for approximately 25% of heat loss, while convection accounts for about 60%. Therefore, together they make up around 85% to 90% of the body’s heat loss in the operating room.
The process of evaporation involves the conversion of liquid sweat on the skin into vapor, which takes away a significant amount of heat from the body. Convection, on the other hand, occurs when the body transfers heat to the surrounding air or objects through direct contact.
It is important to note that while radiation and conduction also play a role in heat loss, their contributions are not as significant as evaporation and convection in the context of an operating room. Radiation accounts for approximately 5-10% of heat loss, while conduction accounts for a minimal amount. Understanding these mechanisms is crucial for maintaining patients’ thermal comfort and preventing hypothermia during surgical procedures.
Overall, in an operating room setting, evaporation and convection are the primary mechanisms responsible for the majority of body heat loss due to their efficient transfer of heat away from the body.
So correct option is D) Evaporation and convection.