Hot-water equipment used in hospitals to conserve energy may be a haven for harmful bacteria, according to a recent study. Changes in a patient's length of stay, which is falling as a result of healthcare payment reform, can also contribute to the problem.
The cautionary tale comes from Centre hospitalier universitaire de Sherbrooke, a 400-bed hospital in Quebec, Canada, which reported two cases of hospital-acquired Legionnaire's disease in August 2014. An investigation revealed that the bacteria came from heat exchangers, which are devices that capture and redistribute excess heat within hot-water systems, according to a study published in Infection Control & Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America.
Twenty-seven out of 34 water samples collected from taps throughout the hospital demonstrated high levels of Legionella pneumophila, and seven out of eight samples taken directly from heat exchangers had high levels of the bacteria. The cases occurred in the year following the installation of the heat exchangers, which are thought to have promoted the bacteria growth, and may have contributed to the recent confirmed cases, according to the study.
Although the hospital found the same strain of Legionella pneumophila in 1995 as a result of proactive testing, there were no confirmed cases of the disease at that time. The hospital ultimately decided to get rid of the heat exchangers, which saved the facility $700 to $1,700 a month on energy savings but may have cost the provider an estimated $34,000 per episode of Legionaries' disease.
The study comes not long after a hospital in Flint, Mich., was sued by patients who allegedly contracted Legionnares' disease at the hospital. McLaren Flint and the patients accused state and local health officials of failing to alert the public to the outbreak, which occurred while Flint residents were dealing with lead contamination in their water supply.
The study's authors say maintaining elevated water temperatures and ensuring constant circulation throughout a hot water system is important to limiting the growth and persistence of Legionella. Stagnant water can be a haven for bacteria and biofilm, which are microorganisms that adhere to wet surfaces.
By continually flushing water through a system, engineers can avoid the buildup of biofilm, which can also absorb chlorine used in water as a disinfectant. This is especially important with hot water, which can lose chlorine more quickly.
Maintaining hot-water circulation doesn't have to be an expensive or complicated task, said Jeffrey Engel, a regional director of operations for ABM Healthcare Support Services, which provides engineering services and other types of support to hospitals. When a New York hospital he previously worked at realized it wasn't getting enough chlorine from city water to maintain adequate disinfection throughout the system, he implemented a water management plan that included both sophisticated equipment and simple human tasks.
The hospital purchased a sophisticated chlorine injector that injects small amounts of chlorine into incoming hot water when a computerized system determines chlorine levels are too low to adequately serve the hospital. But Engel's team also asked cleaning staff at the hospital to run hot water in sinks and showers in patient rooms when they're being cleaned, to ensure that water is frequently flushed through the system.
Engel said flushing water through hot water systems has become especially important in recent years as the average length of stay at American hospitals has gone down. Patients aren't using showers as often, which means water in patient bathrooms can become stagnant.
Although Legionnaire's disease comes from inhaling water through the respiratory system, not ingesting it, showers can promulgate the disease because of the mist created during a hot shower, Engel said. Hospitals have to proactively test their systems and implement water management programs to ensure they're keeping patients safe, he said.
“More and more commonly we find out we have it because somebody got sick and we now we need to figure out why,” Engel said. “With the way healthcare is changing, and your lengths of stays aren't what they used to be, and we change patient rooms so quickly,” it's important to take proactive action, he said.