Which lifting technique involves one rescuer grasping the patient's armpits while another holds the knees?

The technique described involves one rescuer lifting the patient by grasping their armpits while another rescuer holds the knees, which is characteristic of the extremity lift. This method is specifically designed for situations where the patient is not too heavy or when a quick, horizontal transfer is needed, such as moving a patient from the ground or a confined space.

The extremity lift is particularly useful in emergency medicine because it allows for a team of rescuers to move the patient effectively while maintaining stability and support. Proper use of this technique helps to minimize potential injury to both the patient and the rescuers by maintaining a good grip on the patient's body.

In contrast, a direct carry is typically used when the patient can be moved in a sitting position without lifting them up using their extremities, and a power lift refers to a specific way of lifting that employs the legs and body mechanics to safely lift a heavy object. Body mechanics involve the principles of efficient lifting and moving, ensuring the rescuer uses their body effectively to avoid injury but does not specify a lift technique. Thus, the extremity lift is the most appropriate answer for the question presented.