1120-7000/036-4$02.00/0 INTRODUCTION In orthopaedic surgery, high-speed-tools are often used for cutting, drilling and milling. During such operations contact with tissue debris and fluids such as blood and irrigation fluid is usual. In previous stud- ies the authors´ workgroup was able to show that these high-speed-tools (1-3) have the potential to contam- inate the environment through aerosols. As a patient could be a reservoir for pathogenic agents like virus- es or bacteria, these clouds could potentially be con- taminated. This results in an increased risk of trans- mission of infections not only for the surgeons, but also for the whole operating team personnel. Through contaminated surfaces and equipment and contami- nated personnel there is also an increased risk of trans- mission for other patients. Use of ultrasound devices as tools for cement ex- traction in cemented revision total hip arthroplasties has spread (4-6). These tools vibrate at a high fre- quency and, like high-speed-instruments, their work- ing heads are rinsed with saline solutions for irriga- tion and cooling. This study was designed to measure the extent of environmental contamination through aerosols produced by an ultrasound device, designed for ce- ment removal. MATERIAL AND METHODS Three equal cylindrical blocks of Palacos R cement (Merck, Darmstadt, Germany) with dimensions of 60 mm diameter and 120 mm length were designed. An ultrasound device (Ultradrive®, Biomet, Warsaw, IN) Hip International / Vol. 13 no. 1, 2003 / pp. 36-39 © Wichtig Editore, 2003 Extension of an aerosol cloud produced by an ultrasound cement removal system E. MAYR 1 , C. LASS-FLÖRL 2 , F. RACHBAUER 1 , N. WALOCHNIK 1 , C. BACH 1 , M. NOGLER 1 1 Department of Orthopaedic Surgery, University of Innsbruck - Austria 2 Department of Hygiene, University of Innsbruck - Austria ABSTRACT: Ultrasound devices are in use for cement extraction in cemented revision total hip arthroplasties. These instruments vibrate at a high frequency. In contact with flu- ids they have the potential to produce an aerosol cloud. In case of infected or colonized patients this can be a source of environmental and body contamination for the surgical team. 12 standardized cuts in cement blocks were performed with an ultrasound device. Irrigation fluid was contaminated with Staphylococcus aureus ATTC 12600. Contamination was detected using standard cultures. Bacterial growth was seen in a 5 x 7 m area. Exten- sion was comparable to aerosol contamination produced by high speed cutters in spinal surgery as well as in hip arthroplasty, yet, concentration was lower. Ultrasound devices, such as the one tested, can produce aerosol clouds that can cover the whole operating room and potentially contaminate the surgical personnel. The same protection is neces- sary for everybody in the operating room for ultrasound devices as for high-speed cutters. (Hip International 2003; 13: 36-9) KEY WORDS: Aerosol cloud, Contamination, High speed cutter, Cement extraction, Ultra- sound