Filter Protects Patients From Exposure to Waterborne Contaminated Medical Equipment

Feb. 18, 2005

Hospital water is a significant source of microbial contamination contributing to the increase of nosocomial (hospital-acquired) infections worldwide, a leading cause of morbidity and mortality especially among immunocompromised patients.

Healthcare regulators around the globe have issued guidelines, many specifying the use of 0.2 micron point-of use filters, to prevent patient exposure to microbiologically contaminated water from drinking or while showering, bathing or hand washing. Attention is now focusing on preventing the problem of exposing patients to contaminated water from commonly used medical devices, such as flexible endoscopes.

To address the problem, Pall Corp. is introducing in Europe the Pall-Aquasafe AQF1C water filter, the latest addition to its line of point-of-use water filters for hospitals and other healthcare facilities.

The new filter is specifically designed to prevent microbial contamination of heat-sensitive medical devices as well as machines that dispense ice and water. The disposable filter, which is installed in the water supply line, is a CE-marked medical device for the European market. It contains a 0.2 micron bacterial retention membrane validated to produce bacteria-free water.

Gastroscopes, colonoscopes, bronchoscopes and other heat-sensitive flexible endoscopes are disinfected and manually rinsed with water to insure the removal of all residual liquid chemical germicide prior to use with patients.

However, the use of tap water for this critical rinsing step in the reprocessing protocol can increase the risk of nosocomial infection if it is contaminated with bacteria, such as Pseudomonas aeruginosa, Legionella pneumophila and other pathogens that can be passed to patients. The World Health Organization recommends that microbiologically clean, sterile or bacteriological controlled water should be used when rinsing medical equipment.

"Water should eliminate the last traces of disinfectant on reprocessed medical devices without introducing a new problem by depositing microbial contaminants onto their surfaces and into their working channels," said Allan Ross, President of Pall Medical. "The simple quick connection of the new Pall-Aquasafe in-line filter provides an instant barrier that protects patients and medical equipment from the transmission of waterborne pathogens."

In addition to medical device reprocessing, the Pall-Aquasafe in-line filter can be inserted into the feed lines of other common water sources where microbial contamination can be a problem, such as ice machines and drinking water dispensers.

The new filter's universal quick connectors on both inlet and outlet ports make it easy to install, disconnect and replace. Each filter is individually tested, has a use life of up to 14 days, and does not require resterilization and validation. This results in less labor to install and maintain, less waste generation and greater cost efficiencies.

Several studies have detected waterborne bacteria in flexible endoscopes. A 2004 study conducted by Hansen,, published in German Medical Science detected microbial contamination in 28 of 108 flexible endoscopes tested. The 2002 Hygiene in Gastroenterology-Endoscope Reprocessing (HYGEA) study detected waterborne bacteria in 30 out of 55 flexible endoscopes tested.

Flexible endoscopes are used for a wide variety of minimally invasive medical procedures to examine internal body cavities, such as the upper gastrointestinal tract (gastroscopy), lower gastrointestinal tract (colonoscopy) and respiratory tract (bronchoscopy). There are approximately 6000 endoscopic departments that reprocess (manually clean) the devices throughout Europe.

There are three major routes through which patients are exposed to waterborne pathogens: 1) consumption by drinking or ice, 2) inhalation of aerosols generated by showers and faucets, and 3) direct contact with water used for wound cleansing or reprocessing of heat-sensitive medical devices.

Source: Pall