Staying Connected - May 2011

Design Requirements for Cleaning and Sterilization
of Medical Cables

Unless designed for single use, medical cables and leads will almost certainly require cleaning, disinfection or sterilization.  Depending upon the intended use, cleaning may range from a simple wipe down with soap to the elimination of all micro-organisms by sterilization.  Cleaning and disinfection requirements must be considered along with functional attributes in the early product design so that appropriate materials and production processes will be specified.

Spaulding Classification

Based on a strategy developed by Dr. Earle Spaulding in the 1960’s, three levels of disinfection are defined based on the risk of contamination spreading from a device to a patient.  Dr. Spaulding was the Chair of the Department of Microbiology and Immunology at Temple University School of Medicine between 1949 and 1972.



Minimum standards for cleaning,
disinfection and sterilization of medical
cables is established by ANSI/AAMI EC53

Both Spaulding and the EPA classified medical cables and leadwires as “non-critical” when considering disinfection or sterilization.  Medical cables and leads typically only come in contact with unbroken skin and do not normally come in contact with mucous membranes.  Non-critical devices typically require only cleaning and low-level disinfection.  If cables or wires come in contact with broken skin or mucous membranes, a higher level disinfection is required.

Minimum Standards Defined

Minimum standards for cleaning and disinfection of ECG Cables and Leadwires are established by ANSI/AAMI EC53.  Section 4.3.1 details cleaning and disinfection requirements:  “The trunk cable and patient leadwires shall be capable of being cleaned and disinfected 15 times with the following materials per section 5.3.1:

  • green soap or alcohol-free hand soap
  • 2% glutaraldehyde solution (such as Cidex)
  • Sodium hypochlorite (bleach) solution 10% in water

Common glutaraldehyde
disinfectant

Alcohol based solutions or other solvent based cleaners are not recommended for cleaning medical cables because they may dry out the jacket causing it to become brittle and fail prematurely.  However, engineered plastics such as Santoprene® offer good to excellent resistance to isopropyl alcohol or other alcohol based cleaners.

Additionally, ANSI/AAMI EC53 section 4.4 establishes sterilization exposure requirements.  If no sterilization method is specified by the cable manufacturer, the standard provides an ethylene oxide sterilization cycle that is repeated ten times.  After ten cycles, “all labeling and performance requirements of this standard shall be met after sterilization.”

Cable Jacket Material



Autoclave is the most common
sterilization method and is unsuitable
for cables made of PVC or polyurethane

When designing a medical cable assembly or leadwire, one of the considerations is the jacket material.  The jacket material is not only the part of the cable or wire that is most visible; it plays a large role in the performance of the finished cable assembly.  A cable jacket offers mechanical, chemical and environmental protection to the conductors within the jacket.

Because the jacket is exposed, the conditions the cable will be used under and how it will be cleaned or disinfected should be considered early in the design stage.

The following table offers guidelines as to the suitability of common cable materials based on various cleaning, disinfection and sterilization methods.  These materials are commonly used for both cable jackets and molded assemblies.

Cleaning and Disinfection

Material

Sodium Hypochlorite (bleach 10%)

Isopropyl Alcohol

Glutaral-dehyde (Cidex)

PVC

Good

Good

Fair

TPE/TPR

Excellent

Excellent

Excellent

TPU

Poor

Poor

Good

Silicone

Good

Excellent

Good

Sterilization

Material

Autoclave

Gamma

Ethylene oxide (ETO)

VHP1 (Sterrad)

Paracetic Acid (Steris)

PVC

Poor

Excellent

Excellent

Good

Good

TPE/TPR

Fair/Good

Excellent

Excellent

Good

Good/ Excellent

TPU

Poor

Excellent

Excellent

Good

Good

Silicone

Excellent

Excellent

Good

Excellent

Good/ Excellent

1- Vaporized Hydrogen Peroxide

Common Cable Jacket and Overmold Materials

  • PVC is one of the lowest cost cable materials.  It is commonly used to insulate conductors and as cable jacket material as well as for molded components.  PVC offers good resistance to alcohols, most solvents and alkalis, but is not suitable for steam sterilization by autoclave.
  • TPE/TPR (Thermoplastic Elastomer or Thermoplastic Rubber) - These materials are often referred to by the trade name of Santoprene®.  TPE/TPR materials have excellent chemical resistance and are suitable for cleaning and disinfection by most methods.  If designed appropriately, TPE/TPE cable assemblies can withstand several hundred autoclave cycles.
  • TPU – Thermoplastic Polyurethane offers excellent mechanical properties including abrasion resistance and tear strength.  Disadvantages of polyurethane material include poor resistance to some common cleaning agents and high temperatures making them unsuitable for sterilization by autoclave.
  • Silicone – Silicone is both very flexible and offers very high flex life.  It is the most common choice where a high number of sterilization cycles by autoclave are required.  Silicone cables can also be disinfected with most common solutions.


Unless specifically designed
to be submerged, soaking cables
or leadwires is not recommended
and can lead to failure

Cleaning and Disinfection Issues

When used at higher than the recommended dilutions, cleaning and disinfection agents can cause damage to cables and leads.  An all too common error is that disinfection solutions such as glutaraldehyde (Cidex) or sodium hypochlorite (bleach) are used at much higher concentrations than intended, causing damage to medical devices such as cables and leads. 

Unless the cable assembly, including connectors, is specifically designed and manufactured to be submersible, it should not be cleaned or disinfected by submersion in a liquid.


Quaternary compounds, such as
didecyl dimethyl ammonium chloride,
Which are designed to disinfect hard
urfaces, are not recommended for
leaning cables and lead sets

Quaternary ammonium compounds such as didecyl dimethyl ammonium chloride are used in a variety of disinfectants commonly used in medical facilities.  The most common trade name is Sanimaster.  While these agents offer a high degree of disinfection, they are harmful to most plastics and should not be used to clean medical cables or leadwires.

Summary

Cleaning, disinfection, and sterilization requirements of medical cables and leads should be considered at an early stage of product development.  Take advantage of our experience and expertise in designing cable systems to withstand your cleaning and sterilization requirements.  Contact us at +1 949-477-9495 or via email to customercare2@affinitymedical.com.

^ back to top

 

Affinity 14th Anniversary


The Affinity team on the company’s 14th Anniversary

Affinity medical celebrated its 14th Anniversary on Thursday, May 19th.  All 234 employees were able to fit into the new combination lunch and meeting room at one time.


All 234 employees packed into the new
lunchroom for a buffet lunch to celebrate
the company’s 14th Anniversary

Company President Mary Phillipp
showing chart of employee growth

After a buffet lunch, Affinity President Mary Phillipp briefly detailed the history of the company because so many new employees had been added in the past year.  “We started with two employees in 1997, grew to eight in 1998 and surpassed 50 in 2003.  On our tenth anniversary in 1997 we had 82 team members and four years later there are 234 of us here today,” said Mary.

Mary told the group that Affinity’s success was built upon excellent quality and great customer service.  “We need to continue to keep our OEM customers happy by exceeding their expectations for quality and on-time delivery.  Our move in February and greater than forecast demand from our customers caused our delivery performance to slip, but we seem to be back on track.” 

“We all need to continue to work hard and stay focused on completely satisfying our OEM partners,” said Mary.  “This next year will be exciting for all of us.”

^ back to top

 

Meet Mireylli Petatan – Engineering Assistant



Mireylli Petatan –
Affinity Engineering Assistant

Mireylli started her career with affinity in April 2008 as a manufacturing associate.  She was soon promoted to Cell Champion and also became Affinity’s most skilled technician at microscopic work, welding platinum wire that was only .0005” in diameter.

“With our engineering group expanding, there was the need for an additional Engineering Assistant,” said Affinity Director of Engineering, Bob Frank. “We posted the position, interviewed a number of applicants and could not be more pleased with our choice of Mireylli.”


Mireylli with her supervisor
Matt Pathmajeyan in test lab



As an Engineering Assistant, Mireylli supports the project engineers by administering documentation including ECNs (Engineering Change Notices), RFMs (Requests for Mock-ups), Work Instructions and drawings.  Her supervisor, Matt Pathmajeyan, says “It is a pleasure having Mireylli on the engineering team.  She is conscientious, dependable and a good communicator.  Because of her background in production, she is able to assist with engineering builds and we all appreciate that.”



Mireylli reviewing documentation with
Engineering Assistant Laura Ramirez

When asked about her transition from production to engineering Mireylli said “My biggest challenge was learning and understanding engineering terms.  After a year I am pretty comfortable, but still have a lot to learn.”  Asked about her goals, she said “I’d like to go back to college and pursue a career in Engineering.”

Mireylli grew up in Southern California and lives near the new Affinity Plant.  She and her husband have a four year old son who she says is her “bundle of joy.”  They are also expecting another child mid December.  When asked about her family Mireylli replied, “What can I say, I love them to death.”

When not working, Mireylli enjoys reading, going to the movies and cheering for her husband every weekend at his soccer games.

^ back to top

 

Announcements, Information and Trivia



A full moon lights the night sky

Moon Trivia

The temperature on the Moon reaches 243° F at midday on the lunar equator and falls to -261° F at night, a swing of over 500 degrees!

Alan Sheppard hit a golf ball that traveled 2,400 feet on the moon, nearly a half mile.

The “land” speed record on the moon is 10.5 miles per hour and was set by the Apollo Lunar Rover.


The Lunar Rover on the
surface of the moon!
– image courtesy of NASA

Apollo astronaut Buzz Aldren
– image courtesy of NASA

Apollo astronauts brought back nearly 2,200 rock samples, weighing over 400 pounds from the moon!

The footprints left on the moon by Apollo astronauts should be visible for at least a million years because there is no wind or water to erode them.

Neil Armstrong fist stepped onto the moon with his left foot.  Edwin “Buzz” Aldrin, Jr. was the second person to walk on the moon.

When Apollo 12 landed on the moon, the impact caused the moon’s surface to vibrate for nearly a minute.

Affinity Customer Care and Hours of Operation



Candy, Suzann and Cesar – the Affinity Customer
Care team - the Affinity Customer Care Team

At Affinity Medical, we don’t have a customer service department.  In place of customer service, we have Customer Care Coordinators.  While our Customer Care Coordinators perform many of the same functions that customer service representative would, we strive to offer our OEM partners more than that.  The job of our Customer Care Coordinators is to take care of our OEM customer partners.

Affinity Medical Technologies Customer Care specialists are available to assist you from 7:00 A.M. until 4:00 P.M., Monday through Friday, U.S. Pacific Time, except holidays.

 

Affinity Medical Technologies

3545 Harbor Boulevard, Suite 150
Costa Mesa, CA 92626 USA
Phone: +1 949 477 9495
Fax: +1 949 477 9499

Email: Customercare2@affinitymedical.com
Website: www.affinitymedical.com
Blog: http://blog.affinitymed.com