In response to increasing environmental and economic pressure, the reuse of
single-use devices has become more prevalent in the United States. Managed
care and Medicare have reduced reimbursements in the past decade, and annual
surgical waste from common operations of the back, knee, and hip has increased
to a reported weight of 1.84 × 107 lb (8.3 ×
106 kg) and a volume of 5 × 106 ft3
(1.42 ×
105m3)1,2.
Consequently, hospitals and surgery centers have sought to cut expenditures
and reduce the amount of surgical waste produced. One method that a quarter of
the hospitals in the United States have begun to use is the reuse of
disposable surgical equipment. Studies involving angioplasty balloons, cardiac
catheterization wires, trocars for laparoscopic surgery, cytology brushes for
bronchoscopic sampling, surgical draping, and endoscopic equipment have all
been evaluated to see whether use of reprocessed single-use devices is
efficacious, cost-effective, and environmentally
sound3-5.
The majority of studies on the cost-effectiveness and efficacy of reprocessed
single-use devices have been on endoscopy equipment. Wilcox reported, in 2000,
that it was both financially and environmentally sound to use reprocessed
single-use devices for endoscopic surgery, and subsequent studies have
confirmed these
findings3. Another
recent study has revealed a substantial economic advantage in the reuse of
pacemakers without any appreciable risk of
infection6,7.
At the time of writing, we knew of no published report evaluating the quality
of reused single-use devices in orthopaedic surgery. The present paper
presents information regarding the current regulations and standards governing
the reuse of single-use devices.
In 1977, the United States Food and Drug Administration announced that
hospitals that reprocess single-use devices would assume full liability for
reprocessing. At that time, the Food and Drug Administration did not provide
any active oversight or enforcement to monitor hospitals or third-party
reprocessors. Despite the fact that no clear data linked the reuse of
single-use devices to patient injury (except in cases of human error), the
Food and Drug Administration changed its course of action and, in August 2000,
announced that it would begin regulating the reuse of single-use
devices8,9.
This had farreaching implications for United States hospitals and third-party
reprocessors. Prior to that decision, the Food and Drug Administration had
subjected third-party reprocessors to the same regulatory requirements as the
original manufacturer but had not enforced premarket requirements against the
third-party reprocessor. The Food and Drug Administration asserted that
"more devices have features that make reprocessing more
difficult."9
Additionally, the reprocessing of single-use devices had become a lucrative
market for third-party reprocessors. Saloman, an executive at a medical device
reprocessing company, estimated that the size of the United States market for
reprocessing of single-use devices is $1.4
billion10. Given
recent data suggesting that only 25% of hospitals currently use reprocessed
single-use
devices11, there is
a large potential for growth in this market. There are currently no data, as
far as we know, on the percentage of hospitals that specifically use
reprocessed orthopaedic
devices11. There
were thirteen third-party reprocessors registered with the Food and Drug
Administration in
20019. This small
number has remained steady in recent years, and, as the market for
reprocessing has grown, the potential profitability of the companies has
increased12. Thus,
given the huge economic potential for this industry and the recent changes in
technology, the Food and Drug Administration decided to take steps to closely
monitor the reuse of single-use devices. The Food and Drug Administration's
new policy is designed to "ensure that the level of cleaning,
disinfecting, and sterilization of reprocessed SUDs affords the same level of
safety and effectiveness for patients as those who receive new
SUDs."9
Reprocessed single-use devices are classified according to three
categories13, which
are defined as follows:
Critical: The single-use device comes into contact normally with sterile
tissue or body spaces during use (risk level III).Semicritical: The single-use device is intended to contact intact mucous
membranes and not penetrate sterile areas of the body (risk level II).Noncritical: The single-use device is intended to make topical contact and
not penetrate intact skin (risk level I and possibly exempt).
Critical: The single-use device comes into contact normally with sterile
tissue or body spaces during use (risk level III).
Semicritical: The single-use device is intended to contact intact mucous
membranes and not penetrate sterile areas of the body (risk level II).
Noncritical: The single-use device is intended to make topical contact and
not penetrate intact skin (risk level I and possibly exempt).
The definition of a reprocessed single-use device under the Medical Device
User Fee and Modernization Act of 2002 is an "original device that has
previously been used on a patient and has been subjected to additional
processing and manufacturing for the purpose of an additional single use on a
patient."13,14
Most orthopaedic devices fall into class 1 (risk level III).
In October 2002, the Medical Device User Fee and Modernization Act amended
the Federal Food, Drug, and Cosmetic Act by adding section 510 (o) (21 U.S.C.
360 (o)). This provided new regulatory requirements for reprocessed single-use
devices. Reprocessors of class-1, high-risk devices must now submit premarket
applications to show that the benefits of reusing the device outweigh the
risks, and they must provide functional performance and sterilization
data15.
Reprocessors of class-2 (risk level-II) devices must submit premarket
notification in the form of 510(k) applications. Additionally, reprocessors of
class-3, low-risk devices, that are not exempt must also submit a 510(k). In
theory, this legislation ensures that reprocessed single-use devices would be
equivalent to predicate devices in efficacy. Premarket applications and 510(k)
applications must report validation data, including cleaning and sterilization
data and functional performance data, which demonstrate that each single-use
device will remain substantially equivalent to its predicate device after the
maximum number of times the device is reprocessed as intended by the person
submitting the premarket notification. Functional performance data from 510(k)
and premarket notification applications are not available in the public
domain. However, summaries of 510(k) and premarket applications are published
documents. Summaries of the 510(k) applications indicate what device the
single-use device was being compared with for functional performance testing
and the relative basis for substantial equivalence. Premarket application
summaries do not indicate functional performance
information9,12-15.
Reprocessors of exempt devices do not need to submit any sterilization or
functional performance data. They must abide by the performance and
sterilization guidelines for the original product. Additionally, they must
guarantee that the chance of a microbe surviving sterilization is not greater
than one in one million, and they must abide by other residual guidelines.
However, in 2002 and 2003, more legislation that removed exemptions from many
devices that were noted to be low risk was enacted; therefore, reprocessors of
these new nonexempt devices must submit a 510(k)
application12,14,16.
The recent Food and Drug Administration regulations have helped to ensure a
minimum level of quality in reprocessed single-use devices. In the orthopaedic
literature, there have been few reports of the regulations and requirements
that are currently in place to monitor the reuse of single-use devices. This
paper presents such current information and regulations. However, in order to
determine whether the reuse of single-use devices is cost-effective and
efficacious in orthopaedics, more studies must be done on other devices such
as orthopaedic shavers, burrs, drill bits, and other arthroscopic equipment.
This could reduce the amount of surgical waste produced and cut costs, without
compromising the safety of the
patient12,14,17.
Hepatitis-B virus has been shown to be sensitive to even low doses of
intermediate disinfectants such as low-concentration glutaraldehyde (0.2%).
This suggests that current guidelines are sufficient for hepatitis-B virus
inactivation8.
Hepatitis-C virus is sensitive to low doses of intermediate disinfectants.
There have been only two reported cases involving the transmission of
hepatitis C from surgeon to
patient26. No case
involving the transmission of hepatitis C has been attributed, as far as we
know, to the reuse of single-use
devices26.
Other Potential Pathogens Creutzfeldt-Jakob Disease
Creutzfeldt-Jakob disease and other transmissible neurodegenerative
diseases are caused by small proteinaceous, infectious agents called prions,
which are known to be highly resistant to inactivation. Most reported cases of
transmission of Creutzfeldt-Jakob disease involve direct brain contact or the
use of contaminated instruments or tissues that have had contact with
infectious brain tissue. The brain, pituitary, and cornea are noted to have
the highest risk of infection transmission. This makes orthopaedic devices
unlikely to transmit Creutzfeldt-Jakob disease, yet, because of the resistance
of prions to chemical and physical inactivation and because of the morbidity
associated with Creutzfeldt-Jakob disease, recommendations for processing
devices that have come in contact with infectious tissue are very
stringent.
In France, medical devices that may have come in contact with infected
brain tissue are required to undergo autoclaving at 134°C for eighteen
minutes. In The Netherlands, autoclaving at 134°C for eighteen minutes for
six cycles is required. NaOH or NaOCl are also used with exposure times of
thirty and sixty minutes, respectively. Some manufacturers recommend that any
device that comes in contact with tissue infected with Creutzfeldt-Jakob
disease should be exposed to NaOH or NaOCl, autoclaved, and then
discarded8.
It should be noted that associating infections with reprocessed devices is
difficult, given the multitude of potential causes of and sources for
infection. Consequently, accurate reporting of infections associated with
reprocessed single-use devices is not available.
Keeping reusable devices from drying out after use is necessary to prevent
the development of an irremovable biofilm of infectious matter. Keeping the
equipment in a basin of soapy water after use prevents biofilm formation.
External fixators may develop a biofilm from the day of surgery. This biofilm
may be difficult to remove even after washing in soapy water. Consequently,
manual reprocessing to flush channels with an enzymatic detergent is a
necessary step regardless of whether the accessory is packaged for
sterilization or whether it is soaked for high-level
disinfection16,23.
Initial cleaning is the most important. The Association for the Advancement
of Medical Instrumentation states that "thorough cleaning and rinsing
are the first and most important steps in the reprocessing of any reusable
medical device. Without thorough cleaning it might not be possible to achieve
high-level disinfection or sterilization of the device. Any organic material
or residual cleaning agents that remain can inactivate the liquid
disinfectant, and protect microorganisms from
destruction."27
The formation of residues that produce toxic chemicals is also possible. For
example, when ethylene oxide and saline solution combine, they form ethylene
chlorhydrin, a toxic chemical that is a product of normal reprocessing. In
1997, the cases of ten patients with corneal injuries caused by an AbTox
Plazlyte sterilization device were
reported28. The
injuries occurred because a chemical agent that was produced after exposure to
plasma conditions interacted with nonferrous metals to produce toxic mineral
salts. The Plazlyte system was not cleared for sterilization of nonferrous
metals. Thus, the sterilization device was misused, leading to patient injury.
Ultrasonic cleaners may also be used to remove particles that are not removed
during manual cleaning.
Choice of Disinfectant
The adequacy of disinfectant guidelines depends upon compliance with the
cleaning process and the effectiveness of high-level disinfectants. Currently,
there is no consensus on the ideal disinfectant and the adequate immersion
time for existing disinfectants. The two most common disinfectants used are
glutaraldehyde and peracetic acid. Internationally, the recommended immersion
time varies between two and twenty minutes. Most countries err on the side of
a longer soaking time when determining guidelines, and, at present, several
countries in Asia have increased the minimum soak time to twenty
minutes8.
Currently, the American Society of Gastrointestinal Endoscopists, the
Society of Gastroenterology Nurses and Associates, and the Association for
Professions in Infection Control and Epidemiology have created standards for
reprocessing endoscopes and endoscopic accessories. According to the
standards, a twenty-minute glutaraldehyde soak is recommended for those
accessories needing high-level disinfection and sterilization is recommended
for all other accessories that cross the mucosal
barrier19. These
recommended exposure times are determined by finding the time at which all of
the bacterial load and most of the spores are killed, and doubling it. For
sterilization cycles, repeated testing is done to determine the exact exposure
time when none of the test organisms can be found
alive8.
Worldwide, the use of glutaraldehyde is considered to be the first line of
antibacterial and antiviral disinfectants. It has a minimum killing time of
one minute for vegetative bacterial pathogens. Endoscopy studies have noted
complete sterilization in as little as two minutes. Two minutes of exposure
time inactivates the human immunodeficiency virus, and five minutes
inactivates the hepatitis-B virus. High titers of Mycobacterium
tuberculosis are destroyed within twenty minutes, and sporicidal activity
of glutaraldehyde is achieved after an exposure of three to four
hours8.
The major problem associated with working with glutaraldehyde is the
potential adverse reactions reported by staff. Glutaraldehyde acts as an
irritant and allergic sensitizer. It has been shown to cause dermatitis,
conjunctivitis, nasal irritation, asthma, and colitis. In Britain, new
regulations8, which
describe facility requirements necessary for hospitals to use glutaraldehyde,
limit the exposure of staff to glutaraldehyde residue. These regulations
require employers to assess the health risks of their staff following exposure
and to ensure adequate control of glutaraldehyde. Ventilation systems must
control glutaraldehyde vapors and keep them below a working limit of 0.05 ppm
(an eight-hour time-weighted average).
Peracetic acid has long been known to be an effective sterilization agent.
However, the oxidizing action of peracetic acid is short-lived. Consequently,
it breaks down quickly into oxygen and dilute acetic acid. Recent
technological advances have made peracetic acid stable for a period of at
least twenty-four hours, allowing it to be used as a sterilizing agent. It is
a strong oxidizing agent and works by releasing free oxygen and hydroxy
radicals. It is sporicidal within a ten-minute contact period.
Peracetic acid may be superior to glutaraldehyde because of its ability to
remove glutaraldehyde-hardened patient material from biopsy channels.
Glutaraldehyde preserves the organic material if it is used without manual
cleaning, whereas peracetic acid dissolves the material. However, the
disadvantages of using peracetic acid include the high capital cost and
processing cost. Because it is less stable than glutaraldehyde, peracetic acid
also requires replacement every twenty-four hours, and its use requires
adequate ventilation. Additionally, use of peracetic acid has been shown to
cause cosmetic discoloration of electroplated components and the bending
section of endoscopes, albeit without any functional damage. At this time, it
is not used by many centers for sterilization
purposes8.
Automated Disinfectors
Most large hospitals have large automated washers for endoscopy sets and
other equipment. These machines have been shown to be more effective in
removing bacteria compared with mechanical washing
methods8. Yet it is
important to note that having an automated washing machine does not remove the
need to clean the device manually. It is imperative that organic material be
removed manually before the device is placed in the automatic washer.
The main advantages of an automated washing system include the
standardization of the disinfection process and disinfection time.
Additionally, use of an automated system minimizes staff exposure and reduces
the likelihood of glutaraldehyde-induced sensitivities. The major disadvantage
of these machines is that they may themselves become reservoirs of infection
because of biofilm and deposit accumulation. If water used for the final rinse
is not clean, then the reprocessed endoscopes may become contaminated.
Additionally, the cost per cycle is likely considerably more than manual
reprocessing costs, without a substantial change in overall reprocessing
time8.
Sterilization Options
Steam sterilization is the ideal method for endoscope disinfection;
however, flexible endoscopes cannot tolerate temperatures of >60°C.
Temperatures of <60°C are too low to guarantee thermal disinfection.
Steam sterilization is suitable for rigid endoscopes and other
non-heat-sensitive devices.
For devices that are heat sensitive, gas sterilization is usually the most
effective method of sterilization. Ethylene oxide gas sterilizers operate at
37°C and 55°C. There are two major impediments to the use of gas
sterilizers. The first is that following gas sterilization, a twenty-four-hour
interval is required before devices may be used again. Additionally, ethylene
oxide is toxic and explosive, and use of gas sterilizers requires strict
environmental control. A safer, but more expensive, form of gas sterilization
is the use of gas plasma. Gas plasma acts at a temperature of 50°C. Gas
plasma is produced by energizing a gas under vacuum conditions. This causes
ions and molecules within the plasma to form oxidizing free radicals. This
form of sterilization requires devices to be cleaned, dried, and packaged
prior to sterilization. Additionally, this form of sterilization is not as
effective for long narrow lumens, and it requires a substantial downtime after
sterilization before devices may be used. Thus, few clinics use gas plasma
sterilization8.
For orthopaedic devices, steam sterilization is the most commonly used
technique. For heat-sensitive devices, gas sterilization is commonly used,
with ethylene oxide being the most often used gas.
How Is Sterility Assessed?
Devices that have been reused must be tested to verify sterility prior to
gaining approval by the Food and Drug Administration for reuse, unless the
device is exempt. One method of assessing sterility in endoscopic devices has
been to inoculate bacteria onto the outside of the device and into the lumen.
The device is then cleaned manually and channels are flushed with solution and
blown dry. Subsequently, they are soaked in glutaraldehyde, and the channel is
then flushed with 70% alcohol or placed in an endoscopic washing machine. The
device is then gas-sterilized with ethylene oxide. Afterward, the device is
cultured to assess the results of sterilization. In vitro studies with use of
bacteria such as Bacillus species, which have been known to be resistant to
inadequate cleaning techniques, have demonstrated the sterility of these
accessories when tested for particular microbes after ethylene oxide
sterilization3.
The Food and Drug Administration's examination of validation data includes
assessing information from processing at the point of use to the completion of
packaging and sterilization and post-processing considerations. Cleaning,
sterilization, and functional performance validation of reprocessed single-use
devices include both design validation and process validation. Design
validation incorporates both the design of the product and the design of the
processes used in reprocessing the device. The cleaning process includes all
steps to remove, inactivate, or contain contamination, beginning immediately
after clinical use of the device, and all subsequent steps to decontaminate,
clean, and package a device up to the first step of the sterilization process.
This includes all quality-control tests. The sterilization process begins with
packaging and any preconditioning other than cleaning (i.e., prehumidification
for ethylene oxide) to the end of any post-process conditioning.
Manufacturers assess functional performance during cleaning and
sterilization processes. Successful process validations must support the
overall design validation. The results of the cleaning and sterilization
validations provide objective evidence that the requirements for a specific
intended use can be consistently fulfilled and are equivalent to those of the
predicate device. However, the functional performance data for these devices,
including orthopaedic devices, are not available in the public domain.
Proper design validation helps to ensure equivalent functional performance
of the device. Functional performance standards are determined by the
manufacturer because the reprocessed device must be functionally equivalent to
the predicate device. Thus, proper design validation from the manufacturer is
essential for maintaining the quality of reprocessed devices. While the
clinical failure of reprocessors to resharpen bone-cutting tools is legendary,
functional performance standards are determined by the manufacturer and are
assessed by the Food and Drug Administration to determine whether reprocessing
returns the device to functional equivalence with the predicate device. Ark et
al. showed that repeated use of disposable bone-cutting blades did not
substantially alter the quality of the
blade29. However,
no standards indicating minimum requirements for reuse of bone-cutting devices
are currently published.
The design of the reprocessed product is set by the design of the original
device because the manufacturer is starting with a used device. The
manufacturer must take into consideration the used-device specifications that
are important for safe and effective use in order to understand the effects of
any reprocessing and to establish performance equivalent to that of the
original device. The design validation must be performed according to
established procedures from the manufacturer that define device
specifications, processing specifications, operating conditions, and
acceptance criteria for both product and processes. The design validation
process must include a risk analysis that should document the identification
of hazards originating from the product and the processes utilized by the
manufacturer and the users of the device both before and after reprocessing,
the tools utilized to analyze the source or sources of the hazard or hazards,
and the risk estimation. Additionally, the design validation must address how
these risks are managed. The design validation should also specify how many
times the particular device being validated can undergo reprocessing. Issues
such as how many times external fixator frames may be reprocessed are
determined by the manufacturer, and the design validation must be approved by
the Food and Drug Administration. The recommendation by the reprocessor as to
the maximum number of times that the device can be reprocessed will also play
an important role in the cleaning and sterilization process
validations14.
While cleaning and sterilization procedures, materials, and product
performance or verification testing are developed and assessed during design,
these processes must also undergo process validations. Traditionally, process
validation encompasses a series of installation qualifications, operational
qualifications, and performance qualifications.
The legal and ethical ramifications of reusing single-use devices are
farreaching. In addition to the question of liability is the notion of
informed consent. Many believe that informed consent from the patient is
essential to limit the liability associated with reuse. Others advocate
institutional evaluation as a means of measuring safety and efficacy and that
such studies remove the need to inform patients when reusing disposable
equipment. If patients are informed that reused equipment will be used in
their surgery, should they pay full price for the equipment used in surgery?
Should patients be informed when devices that are exempt from the submission
of functional performance and sterilization testing (so-called grandfathered
devices) are used on them?
There are certainly no clear answers to these dilemmas, and there is no
existing case law regarding reprocessed single-use devices. Therefore, it is
essential that, prior to the reuse of disposable bone-cutting and shaping
tools, a committee be formed to assess the liability and legal factors
associated with reuse. A committee that includes legal counsel, bioethicists,
and healthcare providers can help to determine the right course of action to
take with regard to informed
consent3,23,31,32.
The recent Food and Drug Administration regulations regarding the reuse of
single-use devices set a minimum standard to monitor the quality and safety of
reprocessed single-use devices. Consequently, the number of hospitals using
third-party reprocessors is likely to increase in the coming years. Reusing
devices, such as orthopaedic shavers, burrs, and bone-cutting devices, can
potentially lead to cost savings and can reduce surgical waste, without
risking patient safety, as long as the functional efficacy of reprocessed
devices is equivalent to new devices. More research should be done to examine
the cost-effectiveness and efficacy of these reprocessed devices to help to
establish minimum standards that will enable hospitals to more effectively
determine whether the reuse of single-use devices is acceptable. Moreover, we
must become more ecologically sensitive as a medical community. Society
expects physicians to advocate changes that improve the environmental health
of the community at large, and part of improving the health of patients
entails improving the environmental health of the community.