The estimated risk of HIV transmission from doctor to patient during an invasive radiologic procedure is quite low, slightly less than the risk during surgery, according to a study from the University of Texas Southwestern Medical Center at Dallas.
An invasive radiologic procedure is any technique that involves use of a needle or scalpel and some type of imaging guidance, such as ultrasound, CT, or fluoroscopy, said Dr. Margaret Hansen, of the university's Department of Radiology, who presented the study's findings at the 95th Annual Meeting of the American Roentgen Ray Society in Washington, D.C. Common invasive procedures include arteriograms, angioplasty, and imaging-guided biopsies and drainages.
The risk of becoming infected with HIV after exposure to infected blood is 1 in 250, according to previous studies. For a patient to become infected with HIV during a radiologic procedure, the radiologist must be infected and injured in a manner that causes bleeding. Then the radiologist's blood must contact the patient in a way that can transmit the virus. It is estimated that 0.4% to 0.7% of the US population is HIV positive.
Injuries occur less often during radiologic procedures than during surgery, according to studies by Dr. Hansen and others. A study of five surgical specialties by the Centers for Disease Control found the rate of recontact (reuse of a contaminated instrument) during surgery to be 29%. The rate of recontact during an invasive radiologic procedure is 0.2%, according to a survey of members of the Society of Cardiovascular and Interventional Radiology (SCVIR) conducted by Dr. Hansen.
The current study found that the estimated risk of HIV transmission from doctor to patient during an invasive radiologic procedure is only 0.03 per million procedures, if the radiologist's HIV status is unknown. The estimated risk of transmission during surgery, according to previous reports, is 0.01 to 0.9 per million procedures. If the radiologist is known to be HIV-positive, the risk is 7.4 per million procedures. The estimated risk during during surgery is 2.4 to 24 per million procedures, if the physician's HIV status is known.
On average, an SCVIR member performs 665 invasive radiologic procedures annually, and this number is rising. However, the estimated risk of HIV transmission from physician to patient is so low that global practice restrictions for interventional radiologists are not warranted, said Dr. Hansen.
Occupational Safety and Health Administration regulations implemented in 1992 make universal precautions, including the use of protective clothing and equipment and prohibitions against recapping sharp instruments, mandatory. "Despite the low risk of HIV transmission, radiologists need to be vigilant about taking all necessary precautions to enhance procedure safety for everyone," said Dr. Hansen.