Chapter 14
When Dr. Kanada arrived on the unit, he ordered an ABG test on Mr. Posey before he picked up the chart.
Dr. Kanada was a house physician in the truest sense of the word. A respiratory specialist, he had no private practice and only worked in the hospital. He depended on other doctors to refer him patients, and was properly careful and deliberate in what he stepped into and out of – he was deferent to those who paid for his meals. Without the kindness and goodwill of other doctors he would have had no practice at all.
His specialty was breathing, but only the act of breathing. He didn’t put in invasive lines or intubate patients, unless he couldn’t refer the job to someone else – someone who had referred to him in the past, or a candidate for a possible referral later – someone he was trying to get in good with that would remember the favor.
He was political in everything he did in the hospital. He was also well thought of by most people, and a great doctor to work with. He was more than competent in every aspect of medicine, but was very specific in the knowledge of it that he cared to share with others, or be involved with for that matter – he only doctored the breathing part, and he refused to get involved with anything else.
His weakness could be seen in the way he interacted with patients. Though he could be eloquent with staff, he seemed a bumbling Colombo type when dealing with patients and their families. He shuffled when he walked, had a shadow for a shave and mumbled as he talked.
I think: he did it on purpose in a utilitarian attempt to save time – the more he talked, the less money he made.
The way he saw it: Since he only did the breathing part, and since the patients he saw all had other, more generalist type doctors, he thought that most of the answers should come from them. He was a specialist, a parts guy, and who wants updates from the parts guy?
He chose, on purpose, to only see the things that he chose to see. He was the kind of doctor that would keep a skeleton alive if it had functional lungs to inflate. His ethics ended at the rib cage.
Kanada also was one of the few people I’ve met who knew how lucky he was. If life were fair, he’d of been a truck farmer in Watsonville like his dad. He had accidentally fallen into his life, at every stage, the right thing had opened up for him -- the church sponsored high school had led to a church scholarship that allowed him to get a theological degree, that led to foreign medical school run by Mormons trying to covert him. His life was a fortunate series of accidents, and unlike most people, he knew it.
An ABG is an arterial blood gas and is used to measure the oxygen content that is actually being delivered to the tissue. It’s not an inferred number, like many of the non-invasive tests available back then; it’s the gold standard of numbers.
Arteries are deep, and under pressure, so it’s harder to drawn blood from them than the more superficial veins, but because they are under pressure they are easier to find.
Normally the radial artery is used to draw from. When a nurse takes your hand to count your pulse- that’s the radial artery. To draw blood from the artery you find the pulse and stick it. Blood will come out under pressure and fill the syringe for you. Normally, arterial blood is bright red, due to the high oxygen percentage that’s held by the hemoglobin of the blood cells. In Mr. Posey’s ABG, the blood was dark, and clearly held little oxygen.
The ABG was run quickly in a small lab that the respiratory care department maintained near the unit. The results showed that Mr. Posey was acidotic, that the oxygen contained in the red blood cells was very low on the arterial side. It meant something specific to me, something specific and bad.
The lungs are exchangers- a trading place for energy and power—a kind of less dysfunctional Enron of the body. Think of it as the bridge that divides antagonistic nations, a place where cold warring powers exchange there spies- it’s like a free zone for uncomfortable meet and greets.
From the right side of the heart, old and used up blood is slowly pumped until, under less and less pressure, it creeps and oozes ever onward. At the end of their journey through the venous system, the individual red blood cells line up in single file and expose themselves to sacks of air—small bubbles in the lungs called alveoli.
Alveoli are tiny grape like structures, and are the ending point of the mechanical breath you take. A breath is a fairly passive event that allows a simple pressure difference (gradient) to power the in and out of respiration. All the body has to do is initiate the process is to not think about it -- and not thinking is easy if you are the body. Initiating a breath is just the twitch of a nerve that’s triggered by an area of the brain that doesn’t require conscious thought, Breathing just happens until it doesn’t happen. Like all good things in life, it’s effortless but profound.
Relax and air comes into the lungs. It slides down the throat and branches off at the trachea—a sort of junction where the esophagus continues downwards to the stomach. A small trap door opens at this junction and with each breath it opens to allow only air to come it (Unless you are drinking and breathing at the same time- and then you might cough and confuse yourself—think of having sex and peeing at the same time- it can be done, but in your mind you clearly know it’s unnatural—and not in a good way.)
From the trachea, air continues to passively descend via the pressure gradient—nature’s way of balancing all things. The tubing, cartilage and muscle, gets smaller and thinner and eventually, branches out in ways that really do resemble grapes on a vine. At the end of the line you find terminal, small air sacks—the alveoli. This is the work area- the neutral border area where two environments meet in a safe place to exchange and do business. Blood meets air, and they trade.
The business is trade; it’s the whole purpose and reason for the lungs. The heart pumps old blood, full of carbon dioxide, to the meeting place—the lungs deliver air full of oxygen to the same place. These two things meet in the alveoli and, again via gradients, exchange the oxygen in the air for the carbon dioxide in the blood. They have to—it’s a physical law.
After the meet and greet in the alveoli, the air is loaded with carbon dioxide. The presence of too much carbon dioxide sends a signal to the brain which triggers an exhale reflex to the lungs and you actively force out your breath – you exhale and then start the whole process again.
The blood, now bright red with oxygen, gets sucked back toward the left side of the heart by the vacuum of hearts distant pumping action, where it begins another delivery cycle of power to the body.
It’s all a simple business exchange -- as long as the product shows up at the warehouse and the trucks arrive on time and transport it away. Combinations of these things not happening are where most of the problems come from.
If the problem comes from the air/lung area it’s known as obstructive disease—something is blocking the road to the alveoli. If the problem comes from the pumping side it’s usually one of two problems—either it’s a low supply of red blood cells (not usually,) or a backup at the pumping station—and this is know as congestive disease.
Mr. Posey’s blood gas (ABG) indicated he was on the congestive side of the problem. His pump, even with all the drugs being used to support it, was failing. The heart was delivering the blood cells to the lungs fast enough, but the left side of the heart, through the weakness of its indirect vacuum action, was not picking them up fast enough, and because of this, blood cells were starting to back up.
In his case, the supply was good, but the distribution system was backlogged and overwhelmed.
That was only part of the problem however; the back up was starting to be system wide. Because the heart pumped poorly, fluid was backing up, first through the lungs, and then back into the veins --reversing the normal process.
If you looked at Posey, you could physically see the changes happening to him – generalized puffiness and swollen tight skin. If you used your finger and pushed of the swollen areas they dented, and then held their dents after you stopped pushing. Other areas of swelling (edema) became noticeable in his backs and legs, as well as other dependent and stagnant backwater places of the body, places where the circulation tended to pool when storage needed. Old intravenous sticks and lab draws done to him in the days before would weep small drops of clear fluid, which you would see on the stained and splotchy sheets that covered Posey’s bed.
Because the venous side of the system was backing up, fluids found it hard to get back into it. (When the Mississippi river is in flood stage, the Missouri had nowhere to go.) The backup in the venous side then led to more backups, until the arterial side became congested too. The fresh, oxygenated blood began to be pumped into pipes that were already full and distended, so the backup and congestion went full circle until the lungs themselves began to fill with fluid.
And this fluid that could be heard in every breath that Posy took. He was drowning in his own juices.
Dr, Kanada reviewed the ABG results, and then asked me to call the surgery department to see who was on call for Anesthesia tonight. He asked me to set up an intubation tray and to get the respiratory technician on the floor. When I asked him if he was going to do the intubation himself, he told me that it depended on who was on call from Anesthesia. I totally understood.
In Mr. Posey’s room, I helped Dr. Kanada lean Posey forward so that he could listen to his chest. After a quick listen with his stethoscope, he turned to me and said, “That’s an outrageous heart rub.” I was a little surprised, because I was sure he was talking about something that was more heart than breathing, so I stared at him and smiled. He smiled back and said, “I couldn’t miss it if I tried.”
Dr. Kanada spoke to Mrs. Posey after listening to her husband’s chest. He recommended intubation to her and she agreed, and then left for the waiting room until it was finished. As she left, the unit ward secretary poked her head in and said, “Youngblood’s on call for anesthesia.” Kanada asked her to page him, and then to let him know when he called back.
Dr. Kanada said that he would put in the arterial line while we waited. I got the tubing and set it up to a pressure line while he prepared the arm.
An arterial line is to an IV as a blood draw is to an ABG. It’s used to more or less continuously evaluate how well the lungs are oxygenating the blood. It’s also used to see how well the lungs are getting rid of the waste products in the blood. For intubated patients that required frequent checks, placing an arterial line was much better than having to stick them every time you needed to test something.
When the arterial line was not being used for testing, it was hooked up to a special module that was plugged in and connected to the monitor. Since the line was placed in the arterial side of the system, it provided a continuous blood pressure record to follow – and made it much easier than taking manual blood pressure to titrate medicine, and gave a better view of what was going on in real time.
Because the arterial side of the body has much higher pressures than the venous side, and because any air introduced into the system from the arterial side went directly into the brain, (and not the more forgiving lungs as the venous side did,) a pressurized bag of saline was used, along with special tubing that was thicker and less compliant that that used for an IV. Once the tubing was pressurized I connected it to the catheter that Dr. Kanada had placed in the artery. I then connected it to a transducer attached to the bed, which was tied to the monitor by a thick cable.
By turning a stopcock that closed the system off to the patient and opened it to air, I zeroed the transducer by pressing a button on the module below the monitor. Turning the stopcock again – now open to the patient and closed to air, I now had the bouncing line of Posey’s blood pressure scrawling across his monitor.
Dr. Kanada finished by suturing the catheter into place, and I then covered it with a sterile pressure dressing. As I stayed in the room to clean up the mess we had made, Dr. Kanada left to wait for a call back from the Anesthesiologist.
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