Inch for inch, surgical diamond knives may be the most expensive equipment in your surgical facility. Unfortunately, they are also among the most fragile. If they are used or maintained improperly, they can chip, break, or be impaired by dried-on tissue and debris. Usually a damaged knife can be repaired, but repairs cost time and money - typically $400 to $800, and several days including shipment to the manufacturer.

The good news is that, when properly maintained, diamond knives can last virtually forever. One of nature's hardest materials, diamonds can be sharpened and polished multiple times with very good results. And if you implement a careful maintenance program, your diamond knives will be clean, sharp and available for surgery for many years to come. Here are a few tips from the experts to get you started.

1

Extend the blade only for surgery, cleaning and inspection. At all other times, keep the blade retracted - even when handing the knife from one person to another. Only the surgeon or a trained staff member should advance the blade.

2
Inspect diamond knives when they are new, after repair, and after every use. This cannot be done with the naked eye. Have a trained staff member inspect the knife under a 40X/100X inspection microscope.

3
Make sure the entire surgery team understands that the blade should only contact human tissue or fluid. Surgeons must not cut sutures with a diamond blade and should never touch forceps or other blades to it during surgery. Always keep diamond knives entirely separate from other instruments, stored in their own individual sterilization tray.

4
Clean your diamond blades regularly. A diamond blade with even the tiniest dried debris may not produce the desired surgical result. For instance, debris can cause tears in Descemet's membrane, one of the innermost layers of the cornea.

To keep your knife clean, always rinse it immediately following surgery with distilled or de-ionized water to remove tissue, blood, balanced salt solution and viscoelastic. Some centers immerse the knife in an ultrasonic cleaner. Ultrasound forces air bubbles between tissue and the blade, making it possible to wash the tissue away without leaving a film. The cost of such a cleaner is $200 to $600. A trained staff member should advance the blade fully, then suspend it for 30 seconds in the ultrasonic cleaner, making sure the blade does not touch the floor or walls of the cleaner. You may submerge the entire knife in the ultrasonic cleaner, but the blade must be fully retracted. Instead of water, you may want to use an ammoniated cleaner, because ammonia will break down protein more effectively.

Another cleaning technique involves using a steam cleaner. This device shoots out a pressurized jet of steam that washes the blade. If you use one of these, do so after ultrasonic cleaning. The prices range from $800 to $1,800.

If you've tried the above techniques and they haven't worked, you may wish to try a special sponge made only for this; it's called a Diamond Knife Cleaning Block, and it's available from Rhein Medical (see contact information, below).

Never use a Styrofoam peanut or Weck cell to stab the blade clean, and never scrub the blade with a Q-tip (you can snag the tip and snap it off).

If you still are unable to remove the debris, consider sending it back to the manufacturer for "deep cleaning." This service is free from some manufacturers.

5
Sterilize your knife with care. First, place it in its own sterilization tray. Then autoclave by steam or by gas. Avoid steam that is hotter than 300ºF or dry heat sterilization; high temperatures may degrade the glue that holds the blade in place.

6
If you do need to send your blade back to the maker for repair or deep cleaning, you need to ship it with lots of TLC. Retract the knife, place it in its sterilization tray and wrap the tray as you would any fragile object. Ship the knife via a carrier equipped to trace your package, or if you use US mail, ship it registered and insured. When properly repaired, a diamond knife can be truly "as good as new."

Further information is available from these companies:
Accutome, (800) 979-2020, www.accutome.com
Diamatrix, (800) 867-8081, www.diamatrix.com
Rhein Medical, (800) 637-4346, www.rheinmedical.com