When one works in the trauma field, or medicine in general, we deal with the need for sterility all the time. We use equipment and devices that are sterile, and we administer drugs and fluids that are sterile. In surgery, we create sterile fields in which to use this sterile stuff.
In the past few years, we’ve come to the realization that the sterility we take for granted may not always be the case. There have been several cases of contaminated implanted hardware. And a few years ago, supposedly sterile injectable steroids were found to be contaminated with fungus, leading to several fatal cases of meningitis.
An article in the New England Journal of Medicine brings a bizarre problem to light: microbial stowaways in the topical products we use to sterilize things. Most drugs and infused fluids are prepared under sterile conditions. However, due to the antimicrobial activity of topical antiseptics, there is no requirement in the US that they be prepared in this way.
A number of cases of contamination have been reported over the years:
Iodophor – contamination with Buckholderia and Pseudomonas occurred during manufacture, leading to dialysis catheter infection and peritonitis
Chlorhexidine – contaminated with Serratia, Buckholderia and Ralstonia by end users, leading to wound infections, catheter infections, and death
Benzalkonium chloride – contaminated with Buckholderia and Mycobacteria by end users, causing septic arthritis and injection site infections
Bottom line: Nothing is sacred! This problem is scarier than you think, because our most basic assumptions about these products makes it nearly impossible for us to consider them when tracking down infection sources. Furthermore, they are so uncommon that they frequently may go undetected. The one telltale sign is the presence of infection from weird bacteria. If you encounter these bugs, consider this uncommon cause. Regulatory agencies need to get on this and mandate better manufacturing practices for topical antiseptics.
Reference: Microbial stowaways in topical antiseptic products. NEJM 367:2170-2173, Dec 6 2012.
A cardiac anesthesiology fellow, and several engineers from the University of Minnesota and a local device company got together over the past few weeks and cobbled together a ventilator from some spare parts. Here’s a picture to give you an idea of what it looks like:
It uses a metal toolbox tray, an Ambu bag, and some other spare parts lying around one of the medical device labs at the university. Essentially, a servo motor intermittently squeezes the Ambu bag, and there are adjustments for how often (rate) and how deeply (volume) the bag is compressed. There is a pressure limiting device included in the system as well.
This project illustrates how we will need to think outside the (tool)box in the coming weeks, especially as the number of severe Coronavirus cases begins to tax our supply of ventilators. And obviously, this thing will not get FDA approval in your lifetime. But if a choice needs to be made between using something like this in a pinch vs letting someone asphyxiate, the answer is pretty clear.
The group has produced a short YouTube video as well (see below), but it is rather short on details. You get to see some partial views of it as it is being tested on pigs. But so far, the concept is promising.
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It’s unusual for me to post on a Saturday, but we are currently living in unusual times. This tidbit caught my attention and I wanted to get this interesting idea out there for all to think about.
Hopefully, it will never come to this. But there are reports from both Italy and New York City that ventilators are in short supply. This video illustrates the technique used in some research that was actually published way back in 2006. It demonstrated the efficacy of using one ventilator on four patients at once. It requires just a few connectors that are readily available.
But remember, this is off-label use and is not condoned by the FDA! And it probably violates every Department of Health and hospital policy written. But in a pinch, it is something to think about.
Obviously, there are lots of possible downsides. Four patients are essentially sharing one circuit. Even though the circuits are one-way, there is always an infectious cross-contamination risk. The paper shows that ventilation should be adequate on both pressure and volume control settings.
This type of thing is a very last resort, and hopefully no one will have to use it!
Reference: A single ventilator for multiple simulated patients to meet disaster surge. Acad Emerg Med 13(11):1246-9, 2006.
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