The sterile bair hugger was placed on the lower body of the patient after e.V.H.It was brought to the attention of the circulator 31 minutes later by the surgical tech.That the warmer was blowing the warm air uncontrolled under the 3/4 sheet (covering the lower extremities of the patient) placed on top of the bair hugger.The circulator turned off the warmer unit and visualized a tear at the connecting point of the extension tube at the distal end of the rolled our bair hugger.