Portable Medical Equipment: A Significant Source of Transmission


By Kelly M. Pyrek

Who cleans portable medical equipment (PME) and how often is just one important question prompted by the data uncovered by researchers at several healthcare institutions in Texas. Along with co-investigators, Chetan Jinadatha, MD, MPH, clinical associate professor at the Texas A&M Health Science Center College of Medicine and chief of infectious diseases at the Central Texas Veterans Health Care System in Temple, Texas, examined the patterns and sequence of touch events among healthcare workers, patients, surfaces and equipment in the hospital environment to better inform their understanding of potential infection transmission pathways.

As Jinadatha, et al. (2017) explain, "High-touch surfaces in the hospital environment, such as bed rails, tray tables, and supply carts, are considered important in the epidemiology of transmission of healthcare-associated infections (HAIs). If not removed adequately, pathogens can remain viable on fomites for months, serving as a source of transmission on a number of susceptible patients."

An additional source of transmission for which there is limited available research, Jinadatha points out, is portable medical equipment (PME). 

"At my hospital, I would see a very dedicated person who would take equipment in and out of patient rooms, getting it cleaned and bringing it back, and I wondered, what happened if and/or when that person was not there -- who ensures that equipment is cleaned?" Jinadatha says, adding that this observation led him to spearhead an observational at his 120-bed Veterans Affairs (VA) hospital in Temple, Texas.

"With the great emphasis on hand and environmental hygiene, I started paying more attention to objects that move frequently between patients and providers, such as computers on wheels," says Jinadatha. "I started looking at hospital policies and found variability -- some places said equipment should be cleaned three times a day while other places said once a day, and I thought, wait, we clean our hands after every encounter so why are we not cleaning things that have a much bigger surface area every day or after every patient encounter? That sparked my interest in studying the issue more closely. We know the challenges we face, and we have anecdotal evidence but we said we should figure this out officially and map it out in an objective manner to see how this all plays a role in infection transmission."

Jinadatha, et al. (2017) conducted their study on six inpatient units, performing continuous 24-hour observation separately on each unit by two research team members observing for eight-hour sessions. Observations of healthcare workers’ touches of surfaces, patient, and objects were recorded in sequence. The observations of touches were recorded as a sequence of events analyzed with sequence analysis software and visually represented by network plots. These plots revealed that almost all the items touched were connected to at least a few other items in a sequence of touches. The patient, the most commonly touched item, had a potential for contamination from other surfaces as well as a potential for transmitting pathogens to other surfaces.

The study data included the surface/medical equipment touched; the order of touches; what the equipment was used for in that interaction (such as a surface work area for IV fluids or medications); whether equipment entered or exited the room – to determine if the equipment is patient dedicated or shared; if disinfection of equipment or surfaces took place at any time during this interaction; and if hand hygiene was performed.

Jinadatha says that most items in the room have the potential to be contaminated if, indeed, the patient is considered the primary source of the contamination, and the patient has the potential be become infected if the other objects are considered the source. He adds that their results illustrating the interconnectedness of touch sequences between HCW and PME are consistent with the study by Hayden, et al. that showed that healthcare workers' hands were contaminated almost as much by touching only the environment in the patient room as when they touched both the patient and environment.

The top 10 items most commonly touched in the patient room were:
1. patient (850 touches)
2. computer on wheels (634)
3. bedrail (375)
4. IV pump (326)
5. bed surface (302)
6. tray table (223)
7. vitals machine (213)
8. wall shelf (110)
9. door (90)
10. in-room computer (78)

Jinadatha and colleagues note that their results demonstrated that PME such as a computer on wheels and IV pump were two of the most highly touched items during patient care. Even with proper hand sanitization and personal protective equipment, this sequence analysis reveals the potential for contamination from the patient and environment, to a vector such as portable medical equipment, and ultimately to another patient in the hospital.

When asked what he thought of the study's results, Jinadatha notes, "Sometimes you are aware of the problem but sometimes you are not aware of the magnitude of the problem. You know people don't wash their hands, for example, but if you look into it and 80 percent of your people don't wash their hands, that's a serious issue that can shock you. It can be a significant reality check. Similarly, I know the computer on wheels goes in and out of patient rooms at our hospital but I didn't realize how integral they are to providers' workflow, as well as how integral they are in potentially transmitting infectious pathogens. So, we conducted a simple analysis where we looked at how many organisms are on these items -- it's simple aerobic colony counts of items in a single day and the point prevalence.  We found, on average, anywhere from 20 to 40 colonies on every sample, and we sampled overbed tables, handrails and the scanner of a computer on wheels, among other objects -- and found an average colony of 40. A recent paper in AJIC discussed how multidrug-resistant organisms (MDROs) are present on portable medical equipment and how easy it is to miss things that carry pathogens that cause disease and how they are integral in our workflow and how they contribute to infections."

Regarding frequency of equipment going in and out of rooms, Jinadatha explains, "There were PME that came in and out of the room after the patient was discharged, such as an IV pole with an IV pump; there were also PME that remain in the room but can sometimes get moved, like over-the-bed tables that stay in the room even after patient discharge. Then there are the PME that go in and out of the room many times, such as the computer on wheels -- it went in and out of rooms multiple times daily and was probably cleaned per hospital policy, but hospital policy varies. HICPAC guidance leaves it up to the facility how intensely PME will be cleaned, so people may clean it once, or clean it three times a day at the most. There is no current standard, and there is a call for HICPAC members to look at that 2008 guideline and define some parameters based on new research. Joint Commission standards requires the maintenance of PME but doesn't define how often to clean it. We need to analyze the problem to determine how big it is and what can be done about it."

As Jinadatha, et al. (2017) note, "Most PME falls under the noncritical patient care device category of the Spaulding Classification Scheme for infection risk. The disinfection of equipment, along with room high-touch surfaces, is one of the highest priorities in the current Joint Commission scores standard 02.02.01 (Joint Commission) with high non-compliance issues. The Centers for Disease Control and Prevention (CDC) recommend that noncritical patient care devices be cleaned on a regular basis but the recommendations are based on time since the last cleaning rather than how frequently the PME is touched/used. For example, the CDC recommends that a computer on wheels (COW) be cleaned once a day or as needed, or an IV pump cleaned following patient discharge or disuse. If contact events or 'touches' are a means of spreading contamination across surfaces in the environment, then cleaning recommendations based on number of touches may be more effective than those based on the passage of time. However, while existing data on touch frequency have helped to identify high-touch surfaces in the patient care environment, it is difficult to continuously track the patterns of touches. Further research is necessary to quantify the degree of surface contamination associated with touch activity."

Part of the issue is determining who is responsible for the cleaning itself. "If you ask hospital leadership, they will say it is everyone's responsibility," Jinadatha says. "But it also depends on whether the workforce is unionized or non-unionized workforce.  Are we going to tell nurses to do it, or are we going to put it on environmental services (EVS) personnel? There is a critical aspect of each of their jobs and who do you want to handle hundreds of thousands of dollars' worth of equipment? In my opinion, in most hospitals, it is a function that is divided between EVS and nursing, but if we can incorporate a system that can track cleaning duties, we see this as an opportunity for everyone to play a role. I might sometimes use a computer on wheels to see a patient who is bedridden, so I don't know why I shouldn't be held accountable for cleaning the equipment that I took into the room. I feel that at the end of the day, if we have a mechanism to hold people accountable, we must do so, and have everyone pitching in on the cleaning responsibilities where appropriate." 

The cleaning process also requires careful consideration of the types of products and formulations used on PME. Some facilities are investing in UV robots, but as Jinadatha notes, "Not every hospital has UV and you can't use UV on the fly, either -- you must have a dedicated enclosed room, such as an equipment room used for decontamination of patient-use items. Most hospitals are using wipes to clean equipment as much as possible after every patient contact and at the end of the day. It is essential, however, for personnel to understand the occasions where certain cleaning products and formulations are not to be used, such as certain wipes that do not kill C. difficile spores. Or if the equipment manufacturer says not to use certain wipes on the items, that must be followed. I believe that adequate cleaning is possible with a simple method of wipes and terminal cleaning or special cleaning for something like C. diff or VRE."

For Jinadatha, the study's results and the magnitude of the data was "eye-opening," and he says that hospitals must be more aware of the potential for disease transmission by PME. "While items on wheels have a convenience factor for healthcare personnel, they have critical infection prevention and control implications," he says. "What I would like to see is an increased general awareness of how portable medical equipment can contribute to infections -- it's achieving a balance of making workflow easier for personnel but also protecting patients. A good rule of thumb may be don't take it into the patient room if you absolutely don't need to. And being generally aware of the need to clean an item like an IV pole, is very important. A lot of nurses use the over-the-bed table or cart on wheels when they insert a catheter and yet that table may not have been cleaned. We also must be able to track equipment and ensure that we are following cleaning policies. We must help personnel be accountable by having some sort of mechanism to ensure that what we say in our policies is performed by personnel daily. And then we can see if more frequency is needed, than what is being done currently."

Other researchers are equally concerned about the role that PME may play in transmitting healthcare-associated infections (HAIs). Suwantarat, et al. (2017) demonstrated that hospitalized patients frequently interact with shared equipment, and these items were often contaminated, and they emphasize that there is a need for protocols to ensure routine cleaning of shared portable equipment. As the researchers acknowledge, "Efforts to improve environmental disinfection in healthcare facilities typically focus primarily on surfaces in patient rooms that are frequently touched by healthcare workers and patients (e.g., bed rails, bedside tables). Portable equipment that is shared among patients (e.g., medication carts, vital signs equipment, wheel chairs, electrocardiogram machines) can also be a potential source of pathogen transmission. Therefore, current guidelines recommend that medical equipment that comes into contact with intact skin is cleaned and decontaminated after each patient use. In clinical practice, nursing staff and ancillary staff are often given responsibility for cleaning portable equipment because they use such equipment while working with patients. However, Havill, et al. (2011) reported that portable equipment was often not cleaned according to written protocols between each patient use."

(In that study, researchers used adenosine triphosphate bioluminescence assays and aerobic cultures to assess the cleanliness of portable medical equipment disinfected by nurses between each patient use. They found that the equipment was not being disinfected as per protocol and that education and feedback to nursing was warranted to improve disinfection of medical equipment. Havill, et al. (2011) report that, "Three hundred ATP readings were taken from 101 rolling blood pressure (BP) units. The median RLU values for the five sites sampled varied significantly, with the control buttons having the lowest RLU value and the pulse oximeter having the highest. The range of ATP RLU values was from 14 to 31,877. The proportion of sites that yielded ATP readings of less than 250 RLUs varied significantly; 44 (76 percent) of the control buttons, 17 (39 percent) of the thermometers, 22 (28 percent) of the blood pressure cuffs, 13 (24 percent) of the machine handles, and 14 (22 percent) of the pulse oximeters. One hundred cultures were obtained from 26 rolling BP units. The median ACCs for the various items were calculated. Median ACCs ranged from 2 to 53, and total ACCs varied significantly from 0 to too numerous to count. MRSA was recovered from two control buttons, one thermometer, one blood pressure cuff, one machine handle, and one pulse oximeter.")

Suwantarat, et al. (2017) conducted a quantitative assessment of direct and indirect contact between patients and portable medical equipment and other fomites that are shared among patients at a 215-bed acute care facility with a 10-bed surgical ICU and a separate 16-bed medical ICU. In addition, they performed a culture survey to determine the frequency of contamination of shared equipment with healthcare-associated pathogens. The researchers report, "During a five-month period, a single observer quantified interactions between hospitalized patients on 6 medical-surgical wards and in the ICUs with portable equipment and other fomites that were either taken inside the room or stopped immediately outside the door followed by patient contact. Interactions required direct or indirect contact between the patient and surfaces in the room and the portable equipment or other fomite. Contact was considered direct if the equipment or fomite directly contacted the patient or environment and indirect if there was no direct contact but personnel touched the equipment or fomite and then touched the patient. All observations were performed between 8 a.m. and 5 p.m. during week days. The frequency of interactions between different types of fomites per room per hour was calculated for the medical-surgical wards and the ICUs."

They continue, "To determine the frequency of contamination of portable equipment with healthcare-associated pathogens, two swabs pre-moistened with sterile normal saline were used to collect cultures from a convenience sample of portable equipment and fomite surfaces on the 6 medical-surgical wards and in the ICUs. The equipment and fomites were cultured during periods when they were not in use. No information was available on when the items had last been cleaned. For large objects, 5- × 10-cm areas were cultured focusing on areas that are commonly touched; for smaller objects, the entire surface area was cultured. The cultures were processed for methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile. A total of 380 interactions between portable equipment or other fomites and patients were recorded during 144 room hours of observation (2.6 interactions per patient per hour). There were 316 interactions during 96 room hours for medical-surgical wards (3.3 interactions per patient per hour) and 64 interactions during 48 room hours in the ICUs (1.3 interactions per patient per hour). Forty-three of the 380 (11 percent) interactions occurred in rooms of patients under contact or droplet precautions. Of the 380 interactions, 156 (42 percent) involved equipment or fomites that made direct contact with the patient or surfaces in the room, including 128 of 316 (41 percent) on the medical-surgical wards and 28 of 64 (44 percent) in the ICU."

For both the medical-surgical wards and the ICUs, Suwantarat, et al. (2017) report that medication carts were the items that most frequently interacted with patients. In the ICUs, the next most frequent objects interacting with patients were cleaning carts, X-ray machines, and wheelchairs. On the medical-surgical units, the next most frequent objects interacting with patients were wheelchairs, food trays, laundry carts, and cleaning carts. For medication, laundry, cleaning carts, and oxygen tanks, all the interactions were indirect (i.e., contact between hands of personnel and the item followed by touching of patients or environmental surfaces in the room). For wheelchairs, food trays, transfer gurneys, electrocardiogram machines, X-ray machines, glucometers, bladder scanners, weigh scales, commodes, vital signs equipment, and Doppler ultrasounds, all interactions involved direct contact between the equipment and the patient or the environment. The researchers emphasize, "Our findings suggest that there is a need for protocols to ensure effective cleaning of shared portable equipment."
Reese, et al. (2017) emphasize that MPE such as Dynamap machines (blood pressure monitoring devices, thermometer and pulse-oximeter), ultrasound machines, electrocardiogram (EKG) bladder scanners and language line translator phones may be significant fomites for the transfer of infections between patients in acute-care settings. The researchers sought to implement a standardized, effective cleaning process for MPE and monitor success of implementation through the use of ATP monitoring and real time data feedback. Education was provided to staff on between use cleaning and an extensive cleaning process to be performed once daily. Cleanliness of MPE was tested through weekly ATP monitoring and the results were provided to floor educators and managers. Median ATP and passing rate were assessed and ATP pass/fail cutoff was set per manufacturer’s recommendations. The passing ATP level was <250 relative light units (RLU), the intermediate level was 250 RLU to 500 RLU, and the failing level was >500 RLU.

Reese, et al. (2017) found that the overall median ATP level of all MPE decreased from 755 RLU (N = 102) to 236 RLU (N = 425) after 16 weeks. The pass rate increased from 19.6 percent to 52.0 percent. The blood pressure cuff ATP level demonstrated a 78 percent decrease from 969.5 RLU (N = 12) to 219 RLU (N = 84).  The pulse-ox ATP level also decreased by 78 percent from 1884 RLU (N = 9) to 407 RLU (N = 86) post-intervention. An 84 percent reduction in ATP level was identified in the language line translator phone (1284 RLU to 198 RLU). The researchers note, "Future directions include broadening the type of equipment that are assessed through ATP, expanding this project to outpatient settings and exploring the sustainability in the absence of ATP data feedback. The improvement of the cleanliness of the equipment potentially has the impact of decreasing infections throughout the hospital."
Snyder, et al. (2016) reiterate that "While equipment should be wiped down with disinfectant between each use, such cleaning has not been reliably incorporated into hospital practices." They conducted an interventional study of the use of an invisible fluorescent ink to promote portable medical equipment cleaning.

According to the investigators, portable devices, including mobile computer workstations, medication administration scanners, blood pressure machines, and glucometers were monitored for cleaning compliance. Over a five-month period on a medical-surgical unit, trained staff discretely applied an invisible ink to pre-determined high-touch surfaces of equipment. Serial numbers were recorded to track devices. Invisible ink was allowed to dwell for 12 to 24 hours to ensure that equipment was utilized in patient care. On return visits, equipment was checked for residual ink using an ultraviolet flashlight; results were tabulated as “clean” if ink was not visible by the ultraviolet flashlight. If ink was detected, investigators revealed these findings to staff, demonstrated appropriate cleaning, and discussed the importance of equipment cleaning to prevent spread of pathogens.

Snyder, et al. (2016) performed 165 observations of fluorescent marking of equipment during the study period. Because of the focus of training, most (67 percent) observations were of mobile computers and medication administration scanners. With intensified monitoring and feedback, equipment cleaning improved over time. Variations were observed per type of equipment-94 percent of portable blood pressure devices (n?=?18) were “clean” as compared to 71 percent of computers (n?=?76). The researchers state, "With strong support from the unit's nursing leadership, invisible fluorescent marking of equipment with real-time feedback have the potential to increase cleaning practices of hospital equipment. However, cleaning of this heavily-used equipment is far from optimized-fluorescent tagging is one method for training staff that is low in materials cost and in time investment."

References and Recommended Reading:
Carling PC, Parry MF, Bruno-Murtha LA and Dick B. Improving environmental hygiene in 27 intensive care units to decrease multidrug-resistant bacterial transmission. Crit Care Med, 38 (2010), pp. 1054-1059
Dancer SJ. The role of environmental cleaning in the control of hospital-acquired infection. J Hosp Infect, 73; pp. 378-385. 2009.
Dumigan DG, Boyce JM, Havill NL, Golebiewski M, Balogun O and Rizvani R. Who is really caring for your environment of care? Developing standardized cleaning procedures and effective monitoring techniques. Am J Infect Control, 38; pp. 387-392. 2010.
Havill NL, Havill HL, Mangione E, Dumigan DG and Boyce JM. Cleanliness of portable medical equipment disinfected by nursing staff. Am J Infect Control, 39 (2011), pp. 602-604.
Huslage K, Rutala WA, Sickbert-Bennett E and Weber DJ. A quantitative approach to defining “high-touch” surfaces in hospitals. Infect Control Hosp Epidemiol, 31 (2010), pp. 850-853.
Jinadatha C, Villamaria F, Coppin J, Dale C, Williams M, Whitworth R and Stibich M. Portable Medical Equipment: A network analysis showing the potential missing link in infection prevention practices. Poster abstract session at IDWeek. Oct. 5, 2017.
Jinadatha C, Villamaria FC, Coppin JD, Dale CR, Williams MD, Whitworth R and Stibich M. Interaction of healthcare worker hands and portable medical equipment: a sequence analysis to show potential transmission opportunities. BMC Infectious Diseases. 2017;17:800. Accessible at: https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-017-2895-6
Reese S, Lequire C, Van Winks T, Bonn J, Knepper B and Young H. Implementation of Cleaning Process for Mobile Patient Equipment. Open Forum Infect Dis. 2017 Fall; 4(Suppl 1): S191.
Rutala WA, Weber DJ, Healthcare Infection Control Practices Advisory Committee. Guideline for disinfection and sterilization in healthcare facilities, 2008.
Snyder R, Gundermann R, Attia F, Shifflet V, Winters A, Mincemoyer S, Whitener C and Julian KG. Making Pathogens Visible: A Fluorescent Marker Used as a Feedback Training Tool to Improve Cleaning of Shared Portable Medical Equipment. Am J Infect Control. Vol. 44, No. 6, Page S36. June 2016.
Suwantarat N, Supple LA, Cadnum JL, Sankar T and Donskey CJ. Quantitative assessment of interactions between hospitalized patients and portable medical equipment and other fomites. Am J Infect Control. Vol. 45, No. 11. Pages 1276-1278. November 2017.

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