How high-level disinfection protects mom and baby

The ultrasound probe is an indispensable tool. In newly pregnant women, vaginal ultrasound helps healthcare providers get clearer pictures of the developing embryo, while in the later stages of pregnancy it is used to capture the status of the cervix and placenta.

I work in a high-volume fertility practice with five other physicians, and we perform approximately 250 ultrasounds weekly, 1,000 per month or 12,000 a year. Our practice has been growing approximately 5 to 10 percent annually. Since we see so many patients, we need a thorough and effective disinfection procedure that isn’t time consuming. In 2017, we implemented high level disinfection. Our patients are young and healthy, and their goal is to get pregnant and ultimately to have a healthy baby. It’s a stressful time for our patients, one filled with hope, anticipation and anxiety, and it’s our responsibility, and duty, to ensure each patient’s well-being. One way we do that is by minimizing the risks of infection, especially from a simple procedure like an ultrasound.

A word of caution

Vaginal ultrasound probes are classified as semi-critical Group A medical products, which means they must be disinfected after every patient examination. Failure to disinfect ultrasound probes can lead to the spread of bacteria and viruses that can put both the mother and unborn baby at risk. Since ultrasound probes contain electronics, they can’t be immersed into a pressure chamber for cleaning. Traditional disinfection methods take a lot of time and require more arduous quality control measures than automated high-level disinfection (e.g., the use of manual MEC test strips). Manual cleaning by wiping down, spraying and wiping, or soaking the probe in chemicals does not always achieve the same level of cleanliness as high level disinfection and may leave patients exposed to infection and harsh chemical residue.

The commonly used Cidex soak is time intensive, and it has a terrible odor.  For this reason, it is usually kept in a separate room away from patients.  The probe therefore has to be detached from the machine every single time it is to be cleaned. Over time, constant detaching of the ultrasound probe can cause the pins inside it to get bent or even broken, and the probe will start to malfunction. 

The alternative solution 

We use high level disinfection for ultrasound probes. With high level disinfection we don’t need to detach the ultrasound probe from the machine. It’s quicker than soaking and there’s no odor, so we can keep the ultrasound probe right in the room with the patient.High-level disinfection is, I believe, the best approach to minimize the risks of cross-contamination and to reduce the likelihood of nosocomial infection (also called hospital acquired infection). Our medical assistants carefully clean our ultrasound probes after every patient exam using high level disinfection and then place a sterile cover over the ultrasound probe before it’s used for the next patient. A cover is also used at the end of each workday so that the probes remain protected from re-contamination overnight.

In 2017 the European Society of Radiology Ultrasound Working Group published best practice recommendations about controlling infection in ultrasound use.  Their recommendations included a minimum of high-level disinfection for interventional ultrasound. A 2017 study conducted by National Health Services Scotland found when low-level disinfection was used, patients were 41 percent more likely to receive positive bacterial cultures after a transvaginal scan. Proper disinfection of the probe and the probe handle are both important. The same study found 80 percent of probe handles were contaminated and were not disinfected regularly.

Since the probe goes inside the body it’s exposed to the mucosal membranes, the vaginal/cervical secretions and whatever blood may be there. We use the high level disinfection to ensure the probe is truly clean and free of any bacteria and viruses. Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States and the major cause of cervical cancer, so it is critical that it be neutralized on ultrasound probes used for vaginal exams. Sonicated hydrogen peroxide is a very effective high level disinfectant in neutralizing HPV. Because of this, we use the sonically activated hydrogen peroxide trophon method on all our transvaginal probes.

At University Reproductive Associates, we provide a full range of infertility treatments to women in three separate locations in New Jersey. We follow best practices for disinfection at each facility. Our practice has a laboratory and an operating room where our IVF is done. Since our entire practice is constantly being inspected by external agencies, we ensure our disinfection procedures are top notch. The safety of our patients and their unborn babies are our top priority. Although our ultrasound probes are always covered with a condom during use, sometimes the condoms can leak or break, so it’s imperative that the probe underneath is high level disinfected and not just wiped down. While the condom does protect patients receiving a transvaginal ultrasound from infection, research has found that leakage rates of 0.9 to 2 percent can occur. Therefore, it is really best practice to ensure high level disinfection is used for all ultrasound probes after each patient exam.

Automated high level disinfection is worth the investment in time, expense and resources to the practice, as it has given us peace of mind, and our patients know they’re getting treated in the safest possible environment. Many women having vaginal ultrasounds may not think to inquire about their providers’ practices, but they should ask whether and how high level disinfection is done on any ultrasound probes being used on them.

As medicine has advanced and we’ve been successful in keeping people who’ve contracted infectious diseases alive, the prevalence of infectious disease in the population has increased. Given this fact, it becomes even more important to ensure our patients are safe as we help them achieve one of life’s most precious goals—having a healthy baby.