Chapter 22
By working through the things around Posey -- the trash, the lines and piles of tubing, I eventually got to Posey himself. He was the quietest part of the room, and easy to overlook with all the bells and whistles surrounding him, all screaming for attention.
It took an hour to get him and the room cleaned up. I drew the morning lab work, arranged for the EKG after the chest x-ray was finished. I slung him up into the air to weigh him, and to get out of the way so I could change the bed linens. I padded the bed with extra linens, all piled on top of the first set and sort of lumpy --all with waterproof draw sheets. I was planning for a long day, with lots of leaking of fluids and other messy events.
As I worked, I drank coffee continuously, grabbing refills from the central station. Even with all the coffee, I was close to tipping out of my chair before the sun came up and illuminated the binds in the room.
The charge nurse came in and told me that she was making Posey a 1:1 for the day shift. Good news and bad news – I could focus my time exclusively on Posey, but it also meant that I would have to focus on Posey because he was going to be busy.
When the hospital gave you only one patient, they were making a statement, because they were too cheap to do it without a good reason. I wondered what the night shift nurse was going to tell me when she finally got around to giving me report.
The charge nurse gave away the surprise a few minutes later when she came back into the room, pushing the balloon pump machine in front of her while asking, “What time did Dr. Lee tell you he’d be in.”
And then Dr. Lee walked in, right behind her.
A balloon pump device is deceptively easy to describe. It’s a long catheter surrounded by a thin balloon, connected to a pumping machine, and timed to trigger with your heartbeat. Think: An apprentice balloon artist that can only do snakes, and needs a straw to do even that. When he finishes the snake, he leaves the straw in – just in case the kid wants more air in it to make it longer after reflection. Add to that a half million-dollar machine to blow into the straw pure nitrogen – to inflate and deflate the balloon a hundred times a minute.
Most questions break down into parts, and the hard part is usually found in the why – it’s the overview place that most good questions revolve around, and something that needs to be explain fairly early in the process to keep others involved. When you use a balloon pump, the why is the easy part – To lower the SVR, and to pump additional blood into the coronary arteries. The how and the what, the mechanical parts of any question, are the puzzles to solve and the things left unanswered and iffy.
When the left side of the heart contracts, it opens the aortic valve and releases the pressure that’s built up in the left ventricle. Pressurized blood gushes out the valve as it opens, and heads up and around the aortic arch to then drop down towards the legs. Branching arteries along the way divert and direct the blood – to get oxygenated blood to the tissues and organs that need it.
The ascending and descending aorta are two parts of the largest and most important artery of the body. It’s big, wide, and straight for most of its length, and the ability of the muscles it’s wrapped with to expand and contract make up a large part the amount of blood pressure that’s used to perfuse the body with oxygen.
Right outside the aortic valve sit the coronary arteries. They look like small nostrils at the bottom of the arch, nostrils up and facing away from the valve. They supply all of the blood that the heart gets, and work by catching the backwash of blood that’s caused when the left ventricle contracts out the valve.
When the coronary arteries fail to, get enough of the backwash of blood, get pinched shut, or are blocked by clots or debris– the heart muscle that’s being fed by the artery dies from the point where the loss of flow starts and everything that lies beyond that point.
This is what a heart attack is – blockage, or bad blood flow that happens inside the coronary arteries.
The balloon pump was some crazy medical engineers solution to these problems – how to get more blood to the coronary arteries, and how to decrease the amount of resistance that the heart has to pump against.
Its genius is in its simplicity; its curse is in its practical utilization.
Art Lee took off his lab coat and draped it over the dirty linen holder. Turning to his left to wash his hands in the room sink, he turned to me and said, “Let’s start.”
I uncovered Posey and draped a sheet around his genitals to pull them away from the insertion site. I prepared the left groin area with antiseptic, and assisted Lee as he put on a sterile gown, after he opened a tray of equipment and spread its contents across the bed. I placed the separate heart monitor leads from the balloon pump machine to vacant areas of skin on Posey – The pump would use these leads to trigger the inflate and deflate cycles.
Lee poked the left femoral artery with a large bore needle and inserted the sheath into it, using the same techniques he’d used with the Swanz the day before, although this time the sheath was larger and he was inserting it into an artery and not a vein.
Lee used the left femoral artery in order to get a straight shot up the aorta. The balloon was large and wrapped around an equally large catheter, and didn’t bend well, so the less contorting it did until it got into position, the better.
Once the sheath was in placed and secured with sutures, Dr. Lee unfurled the balloon. White, thick and bulky, it looked massive as it entered the sheath; it seemed impossible to fit anywhere in the body without blocking something important, but it was covered with a silicon lubricant, and in it went.
Lee threaded the balloon up the femoral artery, using some real pressure with his hands to move it against the current of the arterial flow that pushed against it. Once it was roughly at a mark he’d guessed it should be, a fluoroscopy machine was moved over the bed to give a better fine-tuning for its placement.
The balloon had to be placed precisely – the top needed to be at the point where the aorta started descending from its arch, and the bottom had to be above the renal arterial branching – so it didn’t occlude the blood flow to the kidneys and starve them of blood.
When the balloon was in position, Lee taped the whole shebang together to keep it from moving, and, using a hand held control crank, manually released the balloon from the catheter by twisting it counter-clockwise. At this point, he connected the hub of the catheter to the machine and turned the switch on.
The pump machine worked by cycling nitrogen into and out of the balloon rapidly – inflating it, then deflating it. Nitrogen was used in case the balloon broke, or leaked – because oxygen let loose in the arterial side of the body would stroke the patient out. The rate that the pump cycled at was set by the heart rate – at a specific spot in each contraction, the balloon would inflate, and at a specific spot, deflate.
An EKG is a representation of the electrical wave that’s generated by the heart. It’s a cycle of the hearts activities that is plotted on a screen to let you know what’s happening. Each plot and position of the cycle gets named with a letter, and each letter represents a different place in the cycle.
The letters used are, P, QRS and T. Each letter is a point along a wave that has a corresponding action in the hearts contraction.
P wave is the initial impulse that electrically signals the start of the contraction (depolarization,) the QRS is the contraction itself, and the T is the period of rest that the heart uses to recharge for the next beat (repolarization.)
The QRS wave corresponds to the time the aortic valve is open and the mitral valve is closed – and the left ventricle is pushing blood forcefully into the aorta. The T wave corresponds with the closing of the aortic valve and the opening of the mitral valve --and the left ventricle is at rest and passively filling up with blood from the lungs.
The balloon pump reads each cycle of the heartbeat and triggers when it sees the signals to inflate and deflate. When the sensor picks up the T wave, it inflates, and the bigger portion of the balloon then pushes all the blood in the aorta down and way from the heart, while the top part of the balloon forces the blood up and bounces it off the aortic valve.
Forcing the blood down empties out the aorta. With the next contraction of the heart there is less blood in the aorta because the balloon pushed it out. With less blood in the aorta, the new contraction has more room to put the blood it’s contracting, so the contraction faces less resistance, lowering the SVR and making its work easier.
And by forcing the rest of the blood up and bouncing it off the valve – the coronary arteries get more backwash forced down their nostrils. More blood in the coronaries means better perfusion of the heart – and more is better in this case – for something not getting enough, too much is a feast.
When the sensor on the balloon pump sees the P wave, it rapidly deflates. When the aortic valve opens at the QRS wave, it opens to an empty tube, and resistance is reduced to almost nothing.
So it’s a twofer – theoretically.
The problem, simply, is that the whole thing is a god-awful mess.
The insertion site where the catheter goes into the artery gushes blood with any movement – usually you have to put sandbags on it to keep it from leaking. The pump reads the EKG fairly well, but arrhythmias through it off, as do fast heart rates or any change in the rhythms at all.
But the big problem is that you have a large foreign object stuck in the major tube of the body that’s moving all the time. Things get push around, blood gets bruised and changes happen to both the clotting times and blood cells themselves – they get chewed up from the turbulence, leaving damaged free radicals and pieces of junk to float around the system and get caught in inappropriate places.
With the Balloon pump in place – oozing and rapidly hissing nitrogen, loud and alive with every heartbeat, I asked Dr. Lee what was happening with the surgical consult.
Lee said that Dr. Cat had been in at midnight to evaluate Posey, but that he had declined to do surgery because of the risk. I asked him, “why Cat,” and he smiled at me. “He was the next one up to ride in the barrel,” he said.
Lee depended on referrals much like Dr. Kanada, and when the results didn’t matter, he kept a rotating list in his head of who to go to next. Dr. Cat was a good teacher, but a lousy surgeon. I knew by his choice of Dr. Cat what Lee though Posey’s chances were.
As we were talking, the balloon pump stopped hissing and the room got quiet. I looked up at the monitor and saw that Posey’s heart rate was over two hundred -- he was in a wide complex ventricular tachycardia that indicated that the pump was without any pumping action. The arterial line reflected this by dropping to a pressure reading on the monitor of zero. There was electrical activity, but no coordinated heart contractions. He was dead until this got fixed.
I slapped the code button on the wall and started pumping on his chest with my hands to give him CPR.
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