Monday, February 18, 2019
"Who doesn't like Queen?"
Music is a simple thing, except for all the complicated stuff. I like lots of different music, and I dislike lots of different music. I like the stuff that sounds good to me, and I dislike the stuff that doesn't sound good to me. Often bands and/or musicians I love will produce songs I can't stand, and often bands I can't stand will produce songs I love. Like I said, simple.
Like pressure and pressure gradients.
We turn to the laws of thermodynamics to understand how materials behave in the real world. In these laws we find the explanation and proof of why gas tends to move from a higher concentration to a lower concentration. Down through the long centuries of painfully slow discovery we've come to find that temperature and pressure are similar ways of talking about the same thing, which turns out to be the movement of molecules.
At the beginning of first semester freshman chemistry you learn about ideal gas laws, which presuppose gas molecules existing in a closed and isolated environment, or container. It's really, really cool, because it makes so much sense. Add heat to the system and the molecules move faster, remove heat and they move slower, all the way down to absolute zero where all molecular motion stops. As the molecules move faster or slower they carry more or less kinetic energy, and impart that energy to other molecules as well as the walls of the closed container. The more energy imparted in these collisions, the higher the pressure, and vice versa. If you open a pathway from your closed, gas-containing container to a separate closed but empty container, the gas molecules will move from the one to the other down the pressure gradient from higher pressure in the full container to lower pressure in the empty container. This flow will continue until the pressure in the two containers becomes equal.
Now let's do something different, but along the same lines. We'll take a transparent container filled with ambient air and featuring a small opening on top and a closed stopcock at some location on the side near the bottom of the container. The exact location of the stopcock doesn't matter. The bottom of the container features a plunger which can slide up and down, rather like the plunger in a syringe. This closes the container except for the hole up top. In this configuration the volume of the chamber gets smaller as the plunger moves up and larger as it moves down, but the pressure remains the same because the hole up top allows inside and outside air to equalize. Now we place a balloon inside the container, affixed to the hole at the top with the mouth of the balloon passing through and solidly anchored in place. As the plunger moves up, decreasing the volume of the container, a couple of things happen. The pressure in the container increases as more molecules are squeezed into a smaller space. The pressure inside the container can't equalize because the balloon has blocked the hole. If you look closely you'll see the balloon shrivel up a bit as increasing pressure in the container presses it flat, forcing the few air molecules in the balloon out through its mouth which is affixed to the hole up top.
Next we move the plunger down, increasing the volume of the container. With the top hole blocked by the balloon, the air in the container still can't equalize with the outside air, so the pressure goes down and falls below ambient (room air) pressure. As this happens outside air rushes through the hole and into the balloon, flowing down the pressure gradient from higher ambient pressure to the lower pressure. As we watch, we see the balloon inflate. Air pressure inside the glass container remains below ambient pressure, and the pressure inside the balloon goes up -- expanding the balloon as air flows in -- until it matches room air pressure. When this happens the balloon stops expanding. Our container now has a partially inflated balloon inside.
Now let's connect some tubing to the stopcock and plug the other end into a vacuum pump. When we open the stopcock the pump sucks all the rest of the air out of the container and the balloon expands to completely fill the space inside the container. The reason it expands to fill the container is that the ambient pressure is higher than container pressure, and room air flows down the pressure gradient and into the balloon until the pressure inside the balloon is the same as ambient pressure. When we close the stopcock everything remains the same. Inside the container, in the very small space between the inner container wall and the outer skin of the expanded balloon, there is now a small negative pressure, and it's this negative pressure which allows the balloon to remain expanded, completely filling the container.
In this new configuration, when we move the plunger up and down, air flows in and out of the balloon as the volume gets smaller and larger, following an ever changing pressure gradient. The container continues to maintain a negative pressure so the balloon continues to fill the entire container regardless of the changing volume.
In this way we've created a crude model of our chest and lungs. The container is our chest, and the inside of the container is our pulmonary cavity. The balloon is our lungs, and the plunger is our diaphragm. The neck of the balloon is our trachea, which is affixed to the hole up top which is our nose and mouth.
For the novice student, the universe suddenly leaps into sharp focus and everything makes perfect sense.
Unfortunately, when you come back to class the following Monday you find that there are no closed systems in reality. The universe gets blurry again. You find that getting down into the weeds of real understanding is going to be a hard slog after all.
But the generalizations hold true. The pressure/temperature gradient is a solid part of the foundation, and you can build on that with confidence. More or less.
For the purposes of this post you really don't need to get down into the weeds. Just remember that gasses flow down the concentration gradient (higher to lower concentration/pressure) just as water flows downhill (higher to lower) in a gravitational milieu.
So there I was, seeing sick call on USS Coral Sea. It was February 12, 1988, and we were operating in the Aegean Sea between Greece and Turkey. It was just another ho-hum day at sea. Twelve days earlier the day had begun in much the same way; just another morning sick call. On that day a young sailor had died in the very treatment room where I was seeing sick call today. Ho-hum can fall apart in an instant.
Unbeknownst to most of the crew, our Battle Group had sent a cruiser and destroyer north the day before. All the way north into the Black Sea. USS Caron (DD-970) and USS Yorktown (CG-48) were exercising Freedom of Navigation and yanking Soviet chains in response to National Command Authority tasking. Anybody remember who NCA was back then?
Yorktown was the second Ticonderoga Class Aegis Cruiser launched.
Caron was a Sprucan named after Wayne Caron, a Hospital Corpsman who fell in Vietnam in 1968 and was posthumously awarded the MOH.
In an interesting coincidence, Wayne Cornell died aboard Coral Sea about six months less than twenty years after HM3 Wayne Caron fell in battle at Quang Nam Province, South Vietnam.
Butt I digress.
Anyway, there I was seeing sick call. As I recall, I was auscultating (listening with stethoscope) a patient's chest when one of the Flight Surgeons caught my eye and gave me the crooked finger c'mere sign.
"Might be a medevac in the works," he said.
In the SMO's (Senior Medical Officer) office the story sounded like this: Yorktown had been bumped by a Soviet destroyer, one of Yorktown's crew had broken some ribs and might have a pneumothorax, and we might need a quick-draw medevac. The Soviets were being pretty belligerent and Yorktown wanted to keep her own helos close by, so we'd scoot up there with an HS-17 Sea King and return with the casualty.
"So get suited up, If this thing goes it'll go in a hurry."
Meanwhile in the Black Sea...
I hustled up ladders and down passageways to my squadron paraloft where my flight gear resided. As I entered there were a pair of pilots and a pair of B/N's donning flight gear as well. I greeted them and assumed they were on the flight sked for the next routine go (launch/land cycle), but as I stripped and began squirming into a wet suit (February in the Aegean after all) they disabused me of that notion.
"What's goin' on Doc? They just set the Alert-30 SUCAP."
Which meant these guys would be manning up a pair of Intruders armed and configured for sinking ships. Ouch!
"Yorktown got bumped by a Russian can and they've got an injury, I guess we'll do a medevac if higher pulls the trigger on it."
As I rolled into the helo squadron's ready room I was reviewing chest injury procedures in my mind while my hands were checking supplies in my medevac kit. In particular I was making sure I had a 10 gauge, 8cm angiocath handy and that there were spares. My mind rolled back several years to a different place and a different ship where a similar injury had prompted a medevac.
In the blink of an eye I recalled how the supposedly stable patient had almost croaked on me and caused me to do my very first needle chest decompression.
Back then the call was from a Perry Class frigate.
The injured sailor had "possible fractured ribs" but was otherwise stable and ambulatory. We had to hoist him aboard because there wasn't room for us to land on the frigate. Technically there was room, and Sea Kings had landed on Perrys, but it was an awfully tight fit, and it just wasn't often done, at least in my experience. So we didn't. A complicating factor was that we couldn't (or shouldn't) hoist a fellow with chest trauma using the horse collar, which fits under the arms and around the back.
Therefore we had to hoist him aboard in a stokes litter.
I chafed a bit at the extra complexity involved as well as the increased risk to the injured man should we go in the water. It's quite difficult to get yourself out of a sinking helo and swim if you're strapped into a stretcher. I made up my mind to get him out of the stretcher as soon as he was aboard.
When we slid the stretcher into the helo everything changed. The injured man's eyes were bulging in panic and he was struggling and failing to undo the stretcher straps. He was obviously fighting to breathe and losing the fight.
My mind and body went into hyper drive. I tore the stretcher chest strap free and ripped open the struggling mans shirt. I could clearly see that his trachea was pushed far to the left as high pressure air from a "punctured" right lung remorselessly pressed on his heart and left lung. If the pressure continued to build in his chest he'd be dead very quickly indeed.
Something had changed drastically for my patient from the time we began to hoist the stretcher to when we pulled it into the helo, a period of about 90 seconds. What was it?
In medical terms he'd developed a tension pneumothorax. In plain English, pneumothorax means "air in the chest cavity," and the tension part means that the air is under pressure. A lot of pressure. If we go back to our container and balloon model, there was now air in the space between the inner container wall and the outer balloon wall. This space is supposed to be empty with a slight negative pressure in both our model and in real live humans. Without negative pressure in that space the lung cannot expand fully, which means at the very least a certain level of respiratory impairment.
The air in the in the man's chest was becoming increasingly pressurized, to the point where it was actually starting to push against and deform the mediastinum (heart and great blood vessels, trachea, esophagus, etc.) and the left lung. Everything was being pushed over to the left, and if the trend continued both breathing and heart function would be compromised, almost certainly leading to death.
Air had entered the sailor's chest cavity from his own lung, injured when he broke some ribs. Initially it had probably been a very small leak, unnoticed by both the patient and the frigate's corpsman. Over time, however, the leak had allowed enough air into the chest that the injured right lung began to be squashed. At some point a bit of lung tissue probably folded over the leaky bit, sealing it off. You might think this would be a good thing because it would seal the leak and prevent further air from entering the chest cavity. Unfortunately, what actually happens is that each time the patient breathes in there's enough pressure inside the lung to push the sealing tissue aside and force more air through the leak. On breathing out the pressure in the lung drops and the tissue sealing the leak moves back into place. What you now have is a one-way valve. More air enters the chest with each breath, but none of it can escape. Air pressure in the chest rapidly builds. This is a bad thing.
The fix is simple. You reduce pressure in the chest by letting the excess air out. Implementing the fix is a bit tricky. You have to open a hole in the chest wall to allow the pressure in the chest to equalize with ambient pressure.
In my training I'd been given a couple of unauthorized tools for just such an occasion. These tools -- techniques really -- were in common use in trauma centers and large emergency rooms, but they hadn't generally been authorized for use in the field by either civilian or military paramedics or EMT's. One was the stab thoracostomy, where you literally stab a knife blade through the chest wall. This was a very last resort, as you can imagine, and you'd better be exactly correct in your assessment and diagnosis before you proceed.
I discarded that tool without much thought and turned immediately to the second unauthorized tool, needle decompression. I zipped open my IV bag and selected a 12 gauge, four inch IV catheter. These are neat technology, featuring a flexible catheter fitted tightly over a needle. When starting an IV you'd poke the needle into the vein, then slide the catheter in and withdraw the needle. Hook your IV tubing up to the catheter and tape it down and you're golden.
Although not designed precisely for decompressing a tension pneumothorax, this style of IV catheter is just about perfect for the job. With one end inside the chest and the other end outside, you've got a clean, neat, and small but adequate pathway to let the high pressure air in the chest escape and equalize.
Moment of truth. With my left hand I felt for and found the correct site; second intercostal space on the mid-clavicular line. I lined up the big needle and catheter and quickly but firmly pressed it home. I could immediately feel pressurized air escaping. The injured man was already breathing more easily before I could tape the catheter in place. Whew!
The rest of the medevac was anticlimactic, at least for me. The injured sailor got a chest tube placed and after a couple of days his lung was healed and reinflated, good as new. The ribs took longer to heal, of course, but he returned to his frigate on light duty and carried on.
I got an attaboy and a stern but appropriate warning to be very careful about performing unauthorized procedures and not to let this success go to my head.
As we landed on Yorktown in the Black Sea on February 12, 1988, I rejoiced that we wouldn't have to hoist a stretcher. A Chief met me as I bounced out of the Sea King and escorted me toward the cruiser's tiny sick bay. The Chief was Yorktown's IDC -- Independent Duty Corpsman, and he gave me a rundown on the condition of the injured man.
"I had to decompress him," said the Chief, "he was really starting to get tight." The sailor looked tense and sore, laying there on the exam table with an IV catheter sticking out of his chest. Not a great position to be in, I guess, but he had no idea how lucky he was!
I, however, knew exactly how lucky I was!
As we launched with our very stable patient and headed back to the Med and Coral Sea, Yorktown was turning about and heading south too, escorted by several Soviet warships and a couple of rusty old freighters. The international incident was winding down.
We can do some pretty impressive things in medicine, but at the end of the day we're just providing rudimentary support to the miraculous living body that nature designed and produced.
It's all very simple, except for the complicated stuff.
Friday, February 15, 2019
The weather guessers called for snow overnight, and they were right. They also called for southerly winds and an afternoon high of more than 40 degrees. They got that right too.
It was pretty frigid this morning, 16 degrees as the sun came up and that southerly breeze felt awfully cold as I began scooping snow.
It wasn't much of a job, scooping an inch-and-a-half of snow, but it did warm me up nicely.
When I finished I hit the weight room and then the road.
I carried my trusty broom along to sweep the underpass steps. Nothing wrong with a little extra care in the "let's don't slip and fall" department, especially when it takes physical effort that can be categorized as exercise!
The sun was fighting through the clouds as I ran steps, making for a pretty light and shadow show.
It was a visual, tactile, and auditory treat.
Then a train came by and it got even more better.
This afternoon it got pretty nice, and the dogs enjoyed a game of ball. Red decided to play Australian (Shepherd) Rules.
I've got a corpsman chronicles in the works. Hopefully I'll get it up tomorrow.
Wednesday, February 13, 2019
When I trot out bits and pieces of my naval career here, I like to talk about the exciting stuff. Flying, Flight Deck, spectacular medical stuff, etc. I was involved in a lot of that and it was all exciting and spectacular. I've got lots of good memories and lots of memories perhaps more remarkable than good.
|Reading the local doggy news|
Whether on the beach or on the boat, however, most of the stuff I did was pretty ho-hum. Mostly interesting, at least from my perspective, but strictly routine. Working the ER/Treatment Room at sea and ashore was fundamentally the same experience. On the boat we wore dungarees, on the beach the uniform was either working blue or working white. On the boat there were no weekends, on the beach there were. On the boat you didn't "go home" at the end of the day, on the beach you did. Other than that, the job was pretty much the same, only without the daily cheap beer hangovers.
|She really likes the funnies|
What filled most of my days was seeing patients in the ER/Treatment Room. On the boat, with limited and cramped space, we saw sick call there, morning and afternoon. Colds and coughs and sore toes and sore backs and tummy upsets and STD's. All the maladies that people develop which are relatively non-acute and certainly non-emergent. On the boat the Treatment room was also the Emergency Room, where we saw acute injuries/illnesses and all of the real emergencies. Those last obviously had head of the line privileges. If a serious illness or emergency cropped up during sick call the routine patients heard "come back tomorrow or, if you're really ill, come back later after we've finished with the emergency."
|I AM taking it easy!|
On the beach with an entire dedicated clinic building,10 times the "crew," and dependents to boot, we typically saw only acute or emergent patients in the ER/Treatment Room. Sometimes on a slow day we might see sick call overflow, but that would usually be a matter of the clinically-trained corpsmen seeing patients in spare exam rooms over on the sick call side of the building. In the ER/Treatment Room proper, 90 percent of the traffic was acute and relatively minor trauma, with perhaps nine percent acute-but-not-quite-emergent illness. That last one percent would be real emergencies, where life hung in the balance. We averaged about one of those per day.
|Watch your step now!|
All of the foregoing is to preface the following.
A couple of years ago when I was having my foot problems -- IV antibiotics followed by surgery and more IV antibiotics over a period of seven months or so -- I noticed a great many similarities between the way our little western Nebraska hospital operates and the way navy medicine -- in my experience -- operated back in the stone age of the 1980's.
I don't say stone age in a disparaging way -- quite the reverse, actually.
What I found at our little hospital is great people. Physicians, PA's, NP's, RN's, LPN's, CNA's, lab techs, xray techs, clerks, Paramedics, etc. Really, really, really good at clinical and emergency medicine.
I felt right at home. So much so that I occasionally have dreams where these local folks appear as members of the naval service in the clinic of my past, and where some of my fellow 1980's sailors appear in this local 21st century hospital as staff members. As do I.
I'm going to try to do a series here on our local hospital. Don't know if it'll fly, but we'll see.
Tuesday, February 12, 2019
Monday, February 11, 2019
Guys at the coffee shop this morning: "Freezing fog again! Never seen so much freezing fog! Must be the global warming!"
Gals at the coffee shop this morning: "Ditto!"
Women who were born men at the coffee shop this morning: "Ditto!"
Men who were born women at the coffee shop this morning: "Ditto!"
People descended from at least 17 various races and ethnicities... "Ditto!"
Since I'm one of those goofy bastards who not only knows how to look up the comprehensive local weather history but has also been recording the weather on a daily basis for more than a decade, I happen to know that freezing fog in February is quite common. On average we've seen freezing fog seven times each February over the last 126 years. For those keeping score at home, that's one out of every four days, and January and March boast similar numbers.
Does it matter? No, not really. Most of those conversations are just morning placeholders as people shake off their overnight lethargy and charge up on legal and socially acceptable drugs.
Do they really believe what they're saying? Do they even care if they believe it? Again, probably not. It's just noise and filler. There's always a lot going on in coffee shop conversations. Gossip and deals and arrangements and touching base.
If the new green wave of social justice rolls over them, takes all their stuff, and moves them into labor/reeducation camps will they understand what's happening, why it's wrong, and what to do to save themselves?
No chance. They'll just shuffle aboard the train, and future historians will wonder why they didn't put up a fight.
Is the new green wave of social justice likely to happen? Probably not.
But in my estimation it's a lot more likely than it would have been five years ago.
I hammered out a five-miler this morning with an emphasis on sprints. I threw in 50 flights of stairs for a bonus. It was a good one.
When I crawled out of bed before the sun I knew, as I know most mornings, that there would just be no way I'd be able to work out. Too old, too tired, too stiff and sore. But as always (at least so far), once I got moving and got the juices flowing my body walked itself over to the workout gear and dressed appropriately.
One motivating factor was the weather report. We're supposed to see high winds today and tomorrow and I hate working out in the wind. Especially if it's a cold wind. As I set out the wind was out of the south and quite cold, but it was also only about 5-6 mph. Better by far to hit it before the gale arrives.
Nona went with me part of the way and acted like she was feeling pretty spry. The aspirin seems to help, but in addition to that the vet said to keep her from going too far and too hard. Therefore my first two miles were a circuit that ended back home, where I delivered her before cranking out the last three miles. We'll see how she responds.
If the 7:1 ratio of dog years per human years is approximately true Nona will catch and pass me in age by the time her eighth birthday rolls around in July. She doesn't do anything by half measures, her motor is either off or at full speed. She doesn't associate physical exertion and activity with the pain that comes later, and she'll just keep on going as long as I keep on going.
*I wuz rong! She'll only be 56! Damme spring chicken! But better at math than me!
As I continue to take the fitness path, I continue to learn what works and what doesn't, what causes and what eases the post-workout aches and pains. I get to decide what I will and will not do. Nona doesn't have any of that, so I have to figure it out for her. It's little enough price to pay in return for all the joy she shares with me.
Sunday, February 10, 2019
Mookie Wilson, John Kruk, and me.
One of these men is not like the others,
One of these fellows just doesn't belong.
Can you tell me which one's not like the other,
By the time I finish this song?
That's right boys and girls, Krukie only has one testicle!
In addition to being MLB All Stars, we three also share a February 10 birthday.
Admittedly, I played my MLB career in a different dimension, but that's such a minor difference that it really doesn't count. Besides, my blog, my rules.
Whilst engaged in my morning workout I received a delightful electronical missive from a farmer friend in Herefordshire.
To which I replied,
Spring will arrive in five weeks. Here on the High Plains at 41N, the daffodils won't come until a month later, but they'll come. And we will see snow encrusted tulips in March.
Poor Nona though, she's been having a problem with hip arthritis. She wants to go with me so bad, but she needs to rest and rehab.
Such a beautiful day, here and in England.
Saturday, February 9, 2019
Every decision, every day, all the way. Some people might think this simple burden constraining and unbearable. I disagree.
Two roads diverged in a yellow wood,
And sorry I could not travel both
And be one traveler, long I stood
And looked down one as far as I could
To where it bent in the undergrowth;
Then took the other, as just as fair,
And having perhaps the better claim,
Because it was grassy and wanted wear;
Though as for that the passing there
Had worn them really about the same,
And both that morning equally lay
In leaves no step had trodden black.
Oh, I kept the first for another day!
Yet knowing how way leads on to way,
I doubted if I should ever come back.
I shall be telling this with a sigh
Somewhere ages and ages hence:
Two roads diverged in a wood, and I—
I took the one less traveled by,
And that has made all the difference.
Is it the path that makes the difference?
Somewhere ages and ages hence:
Two roads diverged in a wood, and I—
I took the one less traveled by,
And that has made all the difference.
Is it the path that makes the difference?
Or is it choosing the path?
Or is it the way you walk the path?