Back to home page
Back to magazine articles

Grim reaper

December 10, 2007

Hospital Infection Control Woes Continue

By  Michael D. Shaw

One of the recurring topics of this column has been infection control in hospitals, and there’s a good reason: The Centers for Disease Control and Prevention (CDC) admit to about 1.7 million hospital-acquired infections per year, with nearly 100,000 fatalities. This works out to 4.5 hospital infections for every 100 patient admissions.

So, a prospective patient—and that includes all of us—might ask what the point of all the new high-tech health care miracles can be, if you just as easily could be felled by an infection?

That’s a great question, and while there are numerous public interest groups working diligently to improve the situation, another potentially dangerous matter has come to the fore. Serious issues have been raised regarding a relatively new and highly touted sterilization method, widely used in hospitals: Hydrogen peroxide gas plasma (HPGP).

Many of you are familiar with the tried and true process of steam sterilization. Back in the day, before the less invasive scope (arthroscopes, laparoscopes, endoscopes) techniques were introduced, it really was possible to sterilize most surgical instruments with steam. However, the scopes (among other devices) cannot handle the heat, and the other tried and true method—ethylene oxide (EtO)—became the gold standard for flexible scopes.

EtO has been used for decades, but like many chemicals before the advent of OSHA, was not always handled safely. EtO was implicated as a possible carcinogen. In fact, the early 1980s saw numerous lawsuits, even as allowable exposure levels for the chemical were drastically reduced and handling techniques were greatly improved. The search was on for an EtO replacement. HPGP was anointed as the answer, and two companies introduced sterilizers with this technology.

As the new sterilizers were rolled out, the hospitals were excited, since not only was the method presumed to be safer to employees, 45-minute cycles could be run, compared to 16 hours with EtO. Instrument inventories could be slashed, and money would be saved.

While it was always known that peroxide would kill the bugs, it was also recognized that the compound is corrosive, and could harm the very devices meant to be sterilized. Thus, the challenge was to use the smallest amount of peroxide that could effect sterilization, without harming the device. Notably, this issue raised questions—from the beginning—on just how well certain devices, especially those with long tubes or “lumens” could be sterilized.

Such concerns prompted one of the manufacturers (the smaller of the two companies) to introduce another sterilant chemical—peracetic acid—into the mix with the HPGP. Unfortunately, this same company got into big trouble with the FDA for marketing its sterilizer without approval, and the sterilizer was implicated in a few incidents whereby damage to the devices caused harm (temporary blindness in one case) to patients.

Possibly, the additional chemical exacerbated damage to the devices, but this was never established, and the smaller company went out of business. Not surprisingly, the other manufacturer took great pains to document compatible devices, and thousands of the HPGP sterilizers were installed.

In the past few years, anecdotal reports of sterilization failure and damage to certain devices had been circulating, as well as stories of minor burns suffered from residual peroxide on the instruments. Still, the number of officially reported incidents to the FDA was minimal, and the march to replace EtO continued.

So much for background. On 15 November 2007, a letter was posted on the manufacturer’s website warning users that because of changes that can occur with medical devices, the compatibility lists are now inoperative. The user is directed to consult the device manufacturer for guidance. To say that the sterilization process has been thrown into confusion would be quite an understatement.

I will not jump to any conclusions about HPGP, but will offer a few observations:

  • Once again, our foolish obsession with chronological superiority caused an undue rush in throwing off a proven technique for an unproven one.
  • It is hard to deny that cost savings based on shorter cycle time trumped concerns over sterilization efficacy.
  • By the same token, sterilization issues are now overshadowed by worries over damaged devices.

I will give you updates on this situation as they become available, but for now would advise any surgical patient to ask tough questions about the sterility and integrity of the instruments going into his body!