Wednesday, February 13, 2008

ZAP



Not many surgeons nowadays would want t0 operate without an electrosurgery unit, but it wasn't all that many years ago that everyone did. In fact, when dinosaurs roamed the earth and I was still in training, a couple of my teachers refused to use it at all. So I learned both ways. Cutting only with a knife, and controlling bleeding only with clamps and ties and sutures has a certain elegance; grace, even, as tying a small vessel requires gentleness and coordination of the fingers so as not to avulse the knot from the bleeder. But it can also be tedious. I wear size 8 1/2 or 9 gloves.

An electrician or physicist I'm not, so I can only say that electrosurgery refers to any of several devices that provide the surgeon with a pencil-like hand unit, connected to some sort of magic box which sends little electrons or something to that hand unit, which then arc to the patient in at least two different modes: one that's best suited for cutting, and one that serves to cauterize; ie, cook tissue to make it stop bleeding ("dead meat don't bleed," a colleague liked to say). I guess the first such devices, widely available only in the last fifty years or so, were those invented by a guy named Bovie. That name has become like Kleenex to facial tissue -- pretty much used generally and generically to refer to any unit, which I assume must annoy the other manufacturers. "Bovie," the surgeon says, and he or she receives a hand-unit most likely made by someone else.

In those days of yore (or mine) the Bovie looked like something from a B-grade science fiction movie, with knobs and buttons and dials; having a fat handle and foot pedals to operate it. "Turn the coag to sixty," the orthopedist would say when encountering bleeding, and the dial would be rotated far to the right, the surgeon would step on the left-hand pedal (there was one each, for cutting current and for coagulating current). Spzzziiiiit the arc sounded, while the floor unit emitted a low-pitched and disquieting hum. Now, we have tidy little boxes with digital readouts, buttons marked ">" and "<" and spiffy hand units with a rocker switch to go from cut to coag, with no need for a pedal. (Most surgeons, I think, like to dance their index finger on that switch -- or buttons, which some "pencils" have -- but I preferred the side of my thumb, which I could rock back and forth without changing my grip.)

I didn't much use electro surgery for cutting, except for going through muscle, preferring the lesser tissue-trauma and greater speed of a knife, cauterizing as needed. You can scald directly, by touching the bleeder with the tip of the unit and firing away. More precise is to clasp the vessel with fine forceps, then touch the blade of the pencil to the metal of the forcep. "Buzz me," is what I'd say after forceptualizing the bleeding point; my assistant would touch the bovie to my instrument and activate it, and I could let go of the tissue at the instant I was happy. Excellent control. Cautery is great for (some kinds of) bleeding from the liver. The old units had a ball-ended option: turn the phaser to stun or kill, press the ball into the wetness, and blast away. It would, of course, smell exactly like grilling liver, and smoke would rise, white, profuse, acrid. (Concerns have been raised and remain, regarding health hazards to the team inhaling that stuff.) "Turn up the coag," I'd request, "and get us some sterile onions."

Sometimes, when it's cranked way up, you can see little lightning bolts running away from the point, for a few millimeters, within the tissues. Spidery sparks, singeing. A charcoal-like coagulum of tissue and baked black blood forms; depending on the nature of the bleeding, blood may continue to ooze from underneath and around, making the field look like an evil-staring eye. Pulling away the cautery unit, stuck like a grill on steak, sometimes also pulls away the char, and you have to start again.

Since sliced bread, the greatest invention is "spray mode" cautery. Using some electromagical manipulations, these new units can be adjusted to provide a white and sizzling rivulet which leaps as if from a Van de Graaf generator, lighting the space between tissue and tip, covering a relatively broad field of fire, cooking without the need for touching. Excellent! No avulsion of clot. Perfect on liver or spleen, where suturing is tricky.

Gathering dust in many an OR are uber-expensive laser units, once sold to hospitals as the next wave, the future of surgical cutting. Better than electric current, and what the public is demanding, they were told. Half-right. For most operations with which I'm familiar, laser offers absolutely no advantage other than marketing. (It has a rightful place in eye surgery, various skin procedures...) In laparoscopic surgery (where laser was predicted to be the ne plus ultra and isn't), there are cleverly conceived devices that combine in one wand, cautery, suction, and irrigation. In the early years of laparoscopy, that was precisely what I thought was needed, and, by golly, here it is. When scissors are added, a lot of annoying motion (taking one instrument out, inserting another, back and forth) will be eliminated. Surgeons nowadays are deeply beholden to engineers.

14 comments:

Michelle in Colorado Springs said...

They still have some old Bovies out there. Not quite as old as the one in the picture but they still use spark gaps and vacuum tubes. They are intresting to fix. What I find intresting is that some of the new ones get software upgrades over a phone line.

Anonymous said...

I know this sounds disgusting but sorry. When I had my c-section I had a lot of nausea. Yet ever so often I got this smell and the dry heaves went away. I just wanted the smell to stay so the nausea would stop!!! Later in the day I started vomiting. When my OB came I asked if he could retrieve that smell for me to make it stop. He got this weird face told me that was the bovie. The smell of my own flesh and blood frying would make me stop with the vomiting!!! He said I've been doing this for 30 years and never heard of such a thing!! On my 2nd c-section the same thing happened!!!

DHS said...

I've never heard the term bovie in any of the (non-US) OTs I've been in, so I guess there was a different first device in the Commonwealth. For us, it has always been "diathermy" (for monopolar) or "bipolar" (for the tweezers).

Have you ever tried the coblation wands? The physics behind them is pretty cool and the demo one of the ENT bosses did when I was assisting him on a tonsillectomy looked great (turn down the OT lights, stick it in water, and see it glow!). Apparently less bleeding and pain after tonsillectomies, to the extent that insurers here are covering the wands at $400 a pop.

sterileeye said...

In Norway we also say "diathermy" and "bipolar".

I've seen special diathermy forceps which are coated in plastic except for the tips and end. But mostly the surgeons use normal, uncoated forceps for cauterizing vessels, leaving the coated ones unused. Why do you have the coated ones? Just as an extra precaution in case your gloves are pierced?

Anonymous said...

In our hospital the electrocautery units recently got even more spiffy: we now have the forcetriad units, which have touchscreens (3 of them!) and even network and usb connectivity :-)

Buckeye Surgeon said...

I can't imagine the days of tying every bleeder. The tediousness of breast biopsies and mastectomies would have been too overwhelming for me.

Another cool device is the argon beam. they use it a lot on the transplant services. It's like a flame thrower; tissue ends up looking like a sered forest after a fire has ripped through...

Assrot said...

Being an engineer of quite some experience and also a former Pre-Med student, I may just have to look into a new design for the laser unit you speak of.

My senior project for my Master's Degree was to build a miniature MRI machine that could be used on extremities only. I did all the design, bought the parts, built the darn thing and wrote the program to control it from a computer.

It seemed to work pretty good but I'm no doctor so I'm not so sure. This was back in the day when they first came out with MRIs.

I wonder what ever became of that device. The university I went to and the Ph.D. that was my advisor made it clear that anything I did in the process of getting a degree belonged solely to him and the university.

I guess it did not become popular since all you see is the huge, full body MRI machines these days.

2nd year vet student said...

Delurking.

assrot:

Standing MRI is actually becoming quite popular in equine veterinary medicine. Involves pretty much the type of machine you're describing. As I understand it, it's pretty convenient (no general anesthesia, less risk for the patient), but the images aren't generally as nice. Still good, but not quite perfect.

Sid Schwab said...

sterileeye: coated ones: yes. Although I didn't use them (not so much by choice as that they weren't always available), there are few things more painful and startling than finding you have a small hole in your glove when holding a forceps that's getting "buzzed." Sometimes the fingers contract from the jolt. And always there's a small char on the skin that lasts for days. It really hurts.

rlbates said...

Amazing though, Dr Sid, even though I too have "found" holes in my surgical gloves using a cautery, I have never had one create a hole in my glove. I often use a finger behind tissue I am cutting to protect some other tissue. I am always amazed that the cautery only cuts the tissue not my glove(d-finger).

Sid Schwab said...

Ramona: if you do have a hole in your glove with that maneuver (which I used all the time, too) you'll know it for days.

And it was a plastic surgeon who pointed out that using cautery for a breast biopsy in the face of an implant was the safe way to go...

make mine trauma said...

I love the smell of the argon beam. It somehow smells so fresh, almost like a fragrance, "ocean breeze" or "cool water" perhaps. Just sliding the handpiece out of it's plastic bag and I get a whiff of it but it smells best when using the beam itself and not so much with the electrode.
Since I don't scrub for the Gyn/Onc anymore(he and one general surgeon are the only ones who still use it), I miss that smell.

Phil said...

Yeah Argon is the go, particularly for Livers.

But very few realize that when using coag, and selecting dessicate should you be in contact with the tissue. Conversly fulguration should be performed with the tip of the blade hovering over the tissue allowing the spark to jump across and coagulate. (if anyone is interested)

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