Hospital Hygiene: Keeping hospitals clean but not sterile
09/01/2004
Standards for contamination and infection control are getting tougher, because a trip to the hospital shouldn't make you sick
BY HANK HOGAN
When the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) talks, hospitals listen. JCAHO is the oldest and largest healthcare accrediting body in the United States. More than 4700 hospitals nationwide voluntarily subject themselves to JCAHO's audits and accreditation. These inspections and certifications are done on a three-year cycle, which means the hospitals coming due in 2005 were last accredited in 2002. This time around those facilities will find a few changes in the JCAHO standards. The differences aren't a surprise but they are on the minds of those involved in controlling hospital contamination and infections.
"The new 2005 JCAHO standards for infection control and their patient safety goal #7 have certainly gotten the attention of healthcare professionals," says Loretta Fauerbach, director of infection control for Shands Hospital (Gainesville, Fla.). She's also a member of the Association for Professionals in Infection Control and Epidemiology (APIC).
One reason for this attention is that the 2005 standards call for procedures and processes to have a measurable impact on infection rates and outcomes. The standards also outline audit methodologies that trace and confirm the implementation of those processes. A look at three areas—construction, sterilization and information management—shows what new contamination and infection control tools and techniques might come under the scrutiny of auditors.
Hard hats and surgical booties
As Shands' Fauerbach notes, there can be sterile fluids and instruments but not necessarily a sterile hospital. A clean hospital, on the other hand, is achievable. This might involve the use of techniques designed to rid surfaces of such organisms as drug-resistant enterococci and Clostridium difficile. The latter contaminates via spores, which makes it difficult to eliminate. In particular, notes Fauerbach, there aren't any hand antimicrobial agents that can kill the spores. The solution is to use gloves and conduct a thorough cleaning before and after a patient is in a room to minimize the spread of the spores.
But Jeanne Pfeiffer, APIC's national president, notes that achieving a clean hospital also involves overcoming a basic fact. Hospitals, unlike other contamination-controlled environments, aren't static structures.
"Hospitals are always under remodeling and redesign—always," says Pfeiffer. "It's just a constant process."
Tim Baugus is a project executive in the Portland office of Skanska USA Building Inc. (Parsippany, N.J.). The company was ranked number one in healthcare construction in 2002 by the Engineering News Record. Skanska USA, according to Baugus, does a lot of hospital construction and renovation. Baugus backs up Pfeiffer's assertion by noting that Skanska USA has been on some Portland-area hospital campuses continuously for 15 years. During that span the company might do a series of small projects intermixed with larger hospital facility expansions and replacements. While these projects, large or small, are underway, the hospital must remain open. That requires taking special contamination control measures and following specialized procedures during construction.
 A technician uses a chemical indicator for sterilization assurance. |
These steps involve the use of HEPA filters, differential pressurization, entry and exit anterooms, surgical booties and sticky mats to ensure that the dust and debris kicked up during construction don't enter the rest of the facility. This is particularly important in hospitals because a form of the mold Aspergillus can be carried in sheet rock dust. Hospitals house people with compromised immune systems, those most at risk of developing one of the diseases related to the mold. Many of these contamination control requirements, Baugus notes, are covered in the mandated Infection Control Risk Assessment Standards (ICRAS) for construction.
"That's a fairly new requirement, although from our perspective we've been doing what the ICRAS guidelines tell you to do for the last 15 years," he says. "There are a lot of contractors that don't do a lot of medical work; if they ever went into a medical environment, it would be a surprise to them what the requirement is."
Baugus notes that airborne particle counts are sometimes done before and during construction. However, hospitals aren't controlled access areas and so it's difficult to get highly repeatable results. Thus, it's hard to draw an accurate picture of what's going on from a potential contamination and infection point of view. However, particle monitoring does have some advantages, especially when compared with the 24 to 48 hours it takes to culture a biological sample.
"Generally it's not wise to do biological monitoring. It's better to do particle counting. It's faster. It's an immediate answer. It's a lot cheaper, and we can do something about it once it's happening," says APIC's Pfeiffer. "Biologicals take a long time."
A clean machine
On the other hand, the time for a biological test has been reduced significantly for some applications. One is the monitoring of sterilization machines, which have seen the process times tumble six fold or more in some cases. These machines are used as part of the cleaning of endoscopes and other devices employed in minimally invasive surgery. Before such minimally invasive devices can be reused, they must be cleaned and any biological contaminants killed. Thus, the cycle time of the sterilization process and the time required to confirm that everything has been killed are a factor in overall surgical throughput.
Balaji Ramamurti, an industry analyst covering medical devices at the growth consulting company Frost & Sullivan (Palo Alto, Calif.), reports that the overall sterilization market is fairly mature. In 2001, the market stood at $647 million and for the most part was growing at a few percent per year. That wasn't the case with the segment that dealt with cleaning endoscopes, which was growing at 7.7 percent annually.
Vendors have attacked the reprocessing cycle time by cutting the time to test and time to sterilize. There are three types of sterilization technologies: steam, ethylene oxide and plasma based. The last is the newest approach, and in it an electrical plasma pumps up the effectiveness of chemicals. This improvement is achieved without boosting temperatures. Advanced Sterilization Products (Irvine, Calif.; www.sterrad.com) makes a line of plasma machines that use hydrogen peroxide.
"The killing power is the hydrogen peroxide molecules. The plasma decomposes or splits those atoms and removes the hydrogen peroxide as a residual from the load that's being sterilized," explains Martin Favero, director of scientific and clinical affairs for ASP.
The cycle time, according to Favero, is less than an hour, and there are plans to cut that time in half within the next year or so. The devices to do this are already available outside the U.S. and the company is in the process of working its way through the Food and Drug Administration approval to sell the machines inside the U.S.
Besides the speed, which Favero says is four to eight times that of competing ethylene oxide sterilizers, the plasma-aided approach does not have any toxic components. Nothing is dumped into the environment other than water and oxygen and there's no need to wait for instruments to cool down or to be flushed of nasty chemicals.
On the testing front, in April the healthcare arm of 3M Co. (St. Paul, Minn.; www.3m.com) announced an extension of its Attest rapid readout biological indicator for monitoring ethylene oxide sterilization. The company's products are loaded into the machine and undergo the sterilization process. They're then removed and can provide proof of success in as little as four hours instead of the 48 or so needed for standard biological monitoring.
Kevin Habas, marketing manager for 3M sterilization, says that the company also makes chemical indicators. These items verify that a sterilization load reached a certain temperature and chemical concentration. These indicators can be read very quickly.
"You'll get that result as soon as you open the door," says Habas.
Depending on how sure a hospital is of its procedures, this quick test may be good enough. The strips used in the biological tests have a high concentration of spores and killing all of the spores is difficult. As a result, no growth, or a negative result, in the biological test is a more certain sign of killing success than the chemical indicators are.
Beyond biocides
Besides faster machines and tests, some hospitals are turning to other technologies for contamination and infection control. One of these additional techniques is based on a service offered by MedMined Inc. (Birmingham, Ala.; www.medmined.com). This method makes use of information technology to spot trends and uncover data buried within hospital and medical records. This is based on data mining, which MedMined chief medical officer Patrick Hymel characterizes as a form of artificial intelligence.
"Data mining is a process where you use very sophisticated technology to discover important patterns within data that may be unsuspected by a human user or a human analyst," says Hymel.
According to Hymel, the process begins by scrubbing the incoming data to assure its cleanliness. Healthcare records have a lot of free-form text entry fields, where the same information may be entered any number of ways. The same term may be spelled differently, for example. MedMined uses an automated process, backed by human intelligence, to assure that the incoming data is clean. This information is then examined for what Hymel describes as patterns in patient results that indicate a process causing or placing patients at risk for infection. Examples could be patients that develop certain infections after undergoing surgery in a particular area.
 The Sterrad 200 System, a large-capacity low-temperature sterilizer, can process up to 150 liters in 75 minutes. |
The system also can pick up problems that originate outside of the hospital. Hymel notes that the service has spotted health problems such as salmonella outbreaks before local public health officials have. Such discoveries, however, cannot be done immediately. Because the system is looking for patterns and not random, individual events, the analysis must look at a long enough time span. According to Hymel, the analysis window typically runs from two weeks to a month.
As for the future, Frost & Sullivan's Ramamurti notes a trend toward putting ultraviolet light in air ducts in order to clean the air circulating within hospitals of pathogens. Ultraviolet light of the right wavelength strikes at the foundation of life because it is absorbed by DNA molecules. That makes it more difficult for a DNA-bearing organism to evolve an ultraviolet defense, unlike antibiotics for which resistant strains have already appeared.
However, such techniques may not help in the destruction of prions, point-like particles that are thought to be the cause of bovine spongiform encephalopathy (BSE, or "Mad Cow disease"). Prions are proteins that reproduce without the need for nucleic acid. Because of this and other prion characteristics many of the standard detection and destruction techniques won't work. That's why reliably detecting and eliminating prions are the subject of research.
Ramamurti says, "Anything to do with prions, either detectors or some kind of indicators to let people know that there are prions in particular medical equipment or not, that could be helpful. Further down the line would actually be coming up with ways and means of destroying these prions."