Prepped: Extended CPR for Shock-Induced Cardiac Arrest

Extremely Important:  Electric Shock (ES) as in lightning can induce cardiac arrest as well as central nervous system (CNS) paralysis.  UNLIKE a heart-attack-induced cardiac arrest, prolonged application of CPR – into several hours has returned people to life after shock.

Most people – including EMT’s and paramedics don’t know this territory well.  Hell, I’ve been  working on electronics with lethal voltages present for more than 50-years and thought I’d read everything.  But, recently I was reviewing some of the earliest articles in the late Wayne Green’s 73-Magazine and right there in one of the opening issues was a description of a shock victim brought back to life after severalhours.

Yes, you read that right:  Hours.

Shock Versus “Normal” C.A.

In “normal” cardiac arrest, the heart. itself is damaged.  When an arterial obstruction cuts off oxygen to the heart, if the obstruction isn’t moved-along, outcomes decline quickly.  If you ever have a heart attack, and you’re in a city proud of it’s CPR program (like Seattle’s famous Medic One program) you may find the first thing a paramedic does is ask if you’re on blood thinner.  Not sure about Seattle’s current protocol, but on-scene administration of a couple of baby aspirin (for its anti-coagulation effect) is not uncommon.

Still, after about 4 or 6 cycles of CPR and defibrillator (10-15 minutes), Cardiac Arrest (from coronary obstruction) outcomes quickly decline.  The heart muscle atrophies and end of game, off to the Big Sleep.

How Shock is Different

Electrocution is a different matter.  Unlike an often gradual obstruction of arterial function, the body of many shock victims is -on average- in good condition.

The administration of the shock simply causes a large number of the muscles in the body to be temporarily paralyzed.   This may include diaphragm (breathing) and heart muscles.  No ticky, no breathy.

Supporting Research

A number of incidents have been reported in medical literature on extended shock recovery cycles.

In a 1998 article in Intensive Care Medicine, Veneman TF1, van Dijk GW, Boereboom E, Joore H, Savelkoul TJ. reported on outcomes in Prediction of outcome after resuscitation in a case of electrocution.”

“Electrical shocks commonly cause widespread acute and delayed tissue damage. Cardiac arrhythmias and respiratory arrest are the most life-threatening complications in the acute phase. Prediction of outcome after cardiopulmonary resuscitation is usually based on neurological findings compatible with anoxic encephalopathy. This report describes a case of electrocution followed by cardiopulmonary resuscitation. Although neurological signs on admission pointed towards severe brain injury, the patient fully recovered and was able to resume the level of cognitive functioning prior to the accident.”

This gets us to the shock action being differentiated effect from other coronary disruptions, as for example, those due to CHD (*coronary heart disease) or blunt-force traumatic injury.

There’s also a case (2016) reported out of Egypt by Motawea M1, Al-Kenany AS2, Hosny M3, Aglan O4, Samy M5, Al-Abd M6. who document a 65-minute recovery with a positive outcome:

“”Electrical shock is the physiological reaction or injury caused by electric current passing through the human body. It occurs upon contact of a human body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair causing undesirable effects ranging from simple burns to death.” Ventricular fibrillation is believed to be the most common cause of death after electrical shock. “The ideal duration of cardiac resuscitation is unknown. Typically prolonged cardiopulmonary resuscitation is associated with poor neurologic outcomes and reduced long term survival. No consensus statement has been made and traditionally efforts are usually terminated after 15-30 minutes.” The case under discussion seems worthy of the somewhat detailed description given. It is for a young man who survived after 65 minutes after electrical shock (ES) after prolonged high-quality cardiopulmonary resuscitation (CPR), multiple defibrillations, and artificial ventilation without any sequelae. Early start of adequate chest compressions and close adherence to advanced cardiac life support protocols played a vital role in successful CPR.”

As you can see, there’s good evidence for  positive outcomes with prompt and prolonged administration of CPR.  For shock, consider applying the process for more than one hour.  As the article in 73-Magzine reported, the application of aid must continue long enough for the seized heart and breathing muscles to relax so they may resume normal function.  That takes time.

Non-Shock Considerations

This is not to say all shock victims can be “brought back” via extended C{R.  Far from it.  There are multiple non-shock risks that accompany electrocution events.

Take the case of a severe power line contact.  In such an even, the contracting muscles and body parts may literally be “blown-off” by the electrical discharges that part of the body is vaporized by high voltage.  I’ve seen cases where hands and arms have been lost due to contact with high-voltage transmission systems.

Another risk is several secondary injury.  Say a person comes in contact with a high-voltage while climbing a power pole.  Here, a fall  may result in life-ending injuries that no amount of extended shock treatment will solve,

The CURRENT is What Kills

People who pursue electronics as a hobby often don’t realize the relatively small current required to stop a human heart.  The Physics Department at Ohio-State offers some very clear guidance to students and faculty:

“Offhand it would seem that a shock of 10,000 volts would be more deadly than 100 volts. But this is not so! Individuals have been electrocuted by appliances using ordinary house currents of 110 volts and by electrical apparatus in industry using as little as 42 volts direct current. The real measure of shock’s intensity lies in the amount of current (amperes) forced though the body, and not the voltage. Any electrical device used on a house wiring circuit can, under certain conditions, transmit a fatal current.

While any amount of current over 10 milliamps (0.01 amp) is capable of producing painful to severe shock, currents between 100 and 200 mA (0.1 to 0.2 amp) are lethal. Currents above 200 milliamps (0.2 amp), while producing severe burns and unconsciousness, do not usually cause death if the victim is given immediate attention. Resuscitation, consisting of artificial respiration, will usually revive the victim.”

We would add the caveat extended resuscitation efforts.  For a “clean”  shock, with no other trauma, such as a related fall or burn trauma, an hour (or more)  of CPR may have good results.

Simple Prevention

Around out electronics bench here at the ranch, we regularly work on high current, high voltage projects.  In the range of 4,000 volts at currents up to one Amp.  (4,000 watts).  When doing this kind of work, we are zealous about safety.  Here are some recommendations:

  • Don’t work on high voltages unless absolutely necessary.  Seems obvious, but when adjusting equipment, there are many processes that can be accomplished turning off power, adjusting, and then testing.  Working anything “hot” is an avoidable risk with few exceptions.  (Neutralizing an RF amplifier output is one…)
  • Make your workspace “shock resistant””
    1. Wear insulated shoes (tennis shoes are fine)
    2. Use a plastic floor mat.  (Saves the floor, too!)
    3. Wear a long-sleeve shirt.
    4. Work with one hand in the pocket.
    5. I wear extra-thick rubber gloves, too.
    6. Ensure adequate lighting of your workspace.
    7. Use a shorting stick to ground high voltage power supplies after they have been shutdown.  This is to discharge capacitors that can hold lethal charge.
  • Have another person in the room with you.  Instruct them how to kill power, how to get you away from equipment, and make sure they have a phone to summon further help.

It sounds like a lot of trouble to go through, but it beats being dead.

Going Slow Pays Off

There is some intrinsic risk to ham radio as a hobby when pursued at the upper limits of the law.  This provides for 1,500 watts peak envelope power (PEP) output from a transmitter.  Since the efficiency of a radio amplifier may be as low as 50-percent, you may run as high as 3,000 watts to make “legal limit out.”  That’s where you might see 3/4ths of an AMP at nearly 4,000 volts used.  Adjusting such equipment is analogous to cleaning a loaded gun.

The ONLY way is to take your time.

Listen to Experience Talking

Two personal stories to learn from:

Years ago, when I was age 13, or so, my uncle had given me an old “ARC-5” command set receiver and it covered the 80-meter ham band.

I quickly built up an A/C to 250-volt DC power supply.  Turned it on and it worked great!  So I decided to move the receiver on my desk a bit.  Reaching behind it, I found myself, a moment later, laying on the floor wondering  “What the hell happened?”

The ARC-5 has an odd mica power connector on the back that was left exposed by my modification.  When I reached behind it to move things…  That was some “shocking” learning.

My second “close brush” with the Grim Reaper was when working on my John son Pacemaker SSB transmitter.  I was adjusting things (one hand, by the book) yet I still managed to brush an exposed high-voltage component with the “karate chop” part of my hand.

These two “learning moments” ensured that in the future I would not leave exposed wiring on the back of any radio.  There are some pieces of equipment that have “safe” terminal strips with high voltage exposed. Fail to cover these and you expose yourself and friends to an avoidable risk.

The SSB transmitter experience taught me about rubber gloves.  Would a simple heavy-duty nitrile glove have prevented the “leaning moment?” (Which smelled like steak, BTW!)  Don’t know and don’t want to find out.  But, anything I can do to “shave the odds” is done without fail.  It’s part of my “Plan to Make 90.”

One last point:  Direct Current (DC) tends to cause “one-way” contractions.  Dropping a hot AC power cable may be easier, but remember, we had a neighbor die a few years ago when she reached under her lawnmower to remove a extension cord that was powering a nearby electric fence.  She’d gotten down on her knees in wet grass to pull out the cord…there was a bit of bare wire exposed…and that was her end.

Electricity is not something to be trifled with…and had I known then what I know now, I would have insisted the CPR be kept up for more than an hour.

I don’t have many regrets in life…but that’s one of them.  Did the EMT’s “call time” too early?  We’ll never know, but there’s a possibility – right there in the data. My regret is a lack of knowledge in depth.

Don’t let it be yours.

Please forward a link to this post to everyone you know who works with serious electricity on even an occasional basis!

Write when you get rich,

3 thoughts on “Prepped: Extended CPR for Shock-Induced Cardiac Arrest”

  1. Truly worthy column today George! I’m sorry about your neighbor. As we both know, we can’t change the past, and even with continued CPR, the results are uncertain.

    I’ve learned a few things from experience and have been lucky enough to live and tell the tales.

    The absolute worst shock of my life happened when directly connecting a bilge pump to a 12 volt battery on a sinking boat while standing in the salt water! Wet hands, no gloves and no time. It was do or die to save the boat, and it worked. I’d rather not do that again.

    The second bad one was working on a metal framed test bench with a floating(ungrounded) oscilloscope. For some reason, I’d been holding part of the bench and put my other hand down on the scope with full hand contact. Very sloppy technique. It was arm to arm and really harsh! I survived, but felt bad the rest of the day. No medical intervention and no idea what my ECG might have looked like, though I’m in good shape now.

    Both events happened in my 20’s. One factor not mentioned is that often people are working alone, and may not be discovered for hours, days, or longer. Life is dangerous – no need to make it more so.

  2. I wonder how many people reading here feel their pulse?
    Mine always skips a beat after 3-9 pulses. Rarely is there a continuous pulse for 30 beats, but I feel fine! During the ‘analog time’ I also worked a long time with electronics, but I never was chocked–until I turned to investing ;-(.

  3. As someone who just today got back from the hospital from such a ‘medical event’, I found your blog today interesting . . . can’t say much about the experience except that one moment I was explaining to the EMT that my chest hurt, and the next memory was that of feeling like an elephant had stomped on me. Kinda sorry I didn’t see tunnels, etc. Guess I get to hang around and drive more people nuts . . .

Comments are closed.