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A 29 year old male was brought in by ambulance after being found lying on the street unconscious.  On ED arrival, he was sleepy but arousable.  He admitted to recent methamphetamine abuse, and he appeared to be coming down from acute intoxication.  On physical exam, he had this significant finding:

Sequelae of a tight ring left on a finger.  The patient was unconscious for several hours after abusing drugs, and thus ignored the swelling of his finger until it was fairly severe.
Sequelae of a tight ring left on a finger. The patient was unconscious for several hours after abusing drugs, and thus ignored the swelling of his finger until it was fairly severe.

He did not have recall any trauma to his hand. He presumed he had laid with his hand compressed in a dependent position, and thus developed ring tourniquet syndrome.

Now what?

The published literature on the topic of ring tourniquets is surprisingly scant.  The best resources I found on the topic were online: Emergency Medicine on the Web and Dr. Sean Fox’s excellent blog, Pediatric EM Morsels.  What I plan to add with my current blog entry are a few tips based on my own experiences, and a two-minute video demonstrating the stringing method of ring removal.

Ring Tourniquet Syndrome: The Pathophysiology

Many of us have rings that we’ve kept on for several years that don’t come off (at least, not easily).  If this is you, don’t panic. A ring that can no longer pass distal to the barrier of a knobby proximal interphalangeal joint (the most common place a ring gets stuck) is not a problem for your asymptomatic, average person.  In fact, if  asymptomatic people have rings that they can’t remove, I’d encourage them to try some home-care tricks of the trade such as a squirt of windex, cold water, and elevation to shrink the digit.

A stuck ring truly becomes a problem when the hand is injured, or when edema of the hand/digits develops for another reason (renal failure with anasarca, passing out with your hand in an awkward position while intoxicated, etc).  In this situation, circumferential edema coupled with extrinsic compression leads to an obstruction of venous outflow from the digit.  This in turn leads to a vicious cycle of worsening venous obstruction, generating worsening edema. Ultimately, either (1) arterial inflow can be cut off, leading to digital ischemia, (2) the soft tissues will give way to the hard metal ring, leading to maceration of the skin directly beneath the ring, or (3) both can happen together.  This is when we move beyond the urgency of a stuck ring in to the emergency of ring tourniquet syndrome.

Ring Removal

When a digit is potentially at risk, get that ring off as fast as possible.  Conventional manual or electric ring cutters are the tools of choice in the ED.  It may take a bit of effort, but ring cutters are effective at cutting most metals (an exception described below).

When time is of the essence, a more powerful tool like a Dremel Rotary Saw can be used effectively to cut a ring off.  It’s even been studied as a tool for this specific situation!  A precaution: these get so hot that you’ll risk thermal injury to the patient’s skin. Thus, you’ll need to take frequent breaks and have a bucket of cool water handy to immerse the finger periodically.  As when working with any power tool, have eye protection for yourself (and the patient).

After removal of the ring, this macerated, secondary injury was discovered.  A small iatrogenic laceration from the ring cutter was unavoidable given the profound edema.
After removal of the ring, this macerated, secondary injury was discovered. A small iatrogenic laceration from the ring cutter was unavoidable given the profound edema.

The Ring “Stringing Technique”

Occasionally, when faced with a thick ring or a hard metal, the tools simply take too long to be effective.  Rarely, a ring may need urgent removal, but will have so much sentimental value that a patient will refuse to let you cut it.  In this situation, you may consider the stringing technique.

This technique is described by many different sources. It sometimes employs the use of thread or dental floss, but when it comes to ED ring tourniquets, I’d recommend using a nice thick 0 nylon suture which can finely compress the tissues and has good tensile strength.  I’d also recommend making sure your patient has received a digital block (preferably a transthecal block), as the compression you’ll provide will be very tight and uncomfortable.  Finally, I would be absolutely sure you have time on your hands.  Contrary to the video above which shows a ring being removed in 2 minutes, in real time, it took about 30 minutes of sequential wrapping/unwrapping to get that ring off.

Exceptional Rings

And now, an exception to any rule: as it turns out, tungsten carbide, the hardest metal to be used in jewelry-making, can’t be cut with a conventional ring cutter, AND can’t even be cut with a power saw!  I learned this firsthand during one of the most challenging ring removal cases I ever experienced in the ED.

Rings made of tungsten can't be cut with conventional tools.
Rings made of tungsten can’t be cut with conventional tools.

After hours of attempting to slip, cut, string, and saw through the metal, we learned the ultimate solution from one of our handy orthopedic surgeons:  we obtained a pair of bolt cutters from our maintenance department and were able to literally shatter the ring from his finger.  As it turns out, tungsten, though incredibly hard, is also incredibly inflexible.  This makes it susceptible to easy breakage when crushed using clamps or vice grips.  A video demonstrating an elegant way to do this can be found here.

Summary

Ring tourniquets can be pretty serious business.  The key point in your average patient is that when an extremity injury is present, make sure all rings are removed immediately to avoid the problem in the first place.  When a ring tourniquet must come off, a basic knowledge of metals used in ring making can help aid in getting the proper tools assembled.  Finally, the stringing tecnhique is a nice trick-of-the-trade if you have time on your hands and a ring you want to save.

 

 

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