My anesthesia command center forms an arc about six feet in diameter at the head of the procedure table; I am like a pilot in a cockpit. A majority of my waking hours are spent inside this circle. I aim to control every aspect of my patient’s care without having to move more than three steps in any direction. Every conceivable need for the care, safety, and comfort of my patient is contained within that arc.
Imagine the face of a clock. I am standing in the center of the face at the point the arms of the dial pivot. My patient’s head rests at twelve o’clock. Along the perimeter at two o’clock, a pair of corrugated, opaque plastic tubes, each an inch in diameter, originate from the anesthesia machine on my right. When stretched, these tubes reach six feet in length. One tube flows oxygen mixed with my anesthesia gases to the patient from the machine, which stands at three o’clock, while the other removes the patient’s exhaled gases. Cables for the patient monitors run along the airway circuit also from my machine to the procedure table.
The anesthesia machine is the CPU (central processing unit), the behemoth of my command center. It stands about five feet high and is about three feet square. It’s loaded with metal weighing many hundreds of pounds, requiring that industrial, six-inch wheels be anchored to the sturdy iron base. A couple of drawers containing machine supplies, extra cables, and manuals sit low; the middle of the machine, the action center, contains all the dials, switches, and buttons for adjusting gas flows to switch modes for breathing. There is also a screen for monitoring the gas composition I provide and the rate and volume of the patient’s breaths that I program.
On top of the machine, a shelf holds the monitor guts and the wire cables leading to the table. A flat screen displays every conceivable number and wave in a variety of sizes from font 16 to 72 and colors (red, green, and yellow). The machine fully loaded is an imposing giant.
Facing the anesthesia machine, on the left side, at waist height and rising over the gas supply tubes, extends a tube arm ending in a soft, expandable plastic bag. The bag inflates with fresh gas that, when squeezed, pushes the gas dialed in from the anesthesia machine circuit through the corrugated tubes coursing to the table. This bag allows me to breathe for my patient.
Jutting out from the machine at waist height is a small work space that holds all the immediate needs for the case at hand. On the left are my tools for ensuring that the patient’s airway remains open and unobstructed, which means he or she isn’t snoring. There are plastic oral airways that look like oversized commas in a variety of sizes, endotracheal tubes (gently curved, clear plastic oversized straws that have a balloon near the end), and my laryngoscope (which lights the path through the mouth to the vocal cords). The drugs I need—the intravenous anesthesia medications, narcotics for pain relief, relaxants for temporary paralysis, and antibiotics—are arranged on the right-hand side of the table. Each syringe is labeled with color-specific tape that indicates its purpose, and each is carefully arranged with the needles pointing toward the machine.
Along the back, right edge of the table are two emergency drugs that I rarely need but always keep at the ready. The voodoo intent is to ward off evil humors. The orientation of the syringes immediately signals to me which drug I’m touching. One is a syringe of a rapidly acting paralyzing agent, succinylcholine; the other contains atropine, a drug to speed the heart. A slowing heart rate is the portent of doom. Slow heart rates progress to no heart rate and full cardiac arrest.
Behind me, at six o’clock on the imaginary clock face, is a cart that could be mistaken for a mechanic’s tool chest. (It probably is one, but because it comes from a medical-supply company, the price is outrageously high.) The top of the equipment cart forms a counter that holds the not-so-urgent supplies for my procedure and provides a small work space for drawing up medications into syringes and such. Below, in six drawers of varying heights, the cart holds anything I might conceivably need for any case, from syringes and hypodermic needles to drugs and airway supplies, just as it might hold all the tools for a mechanic. The bottom drawer contains suction catheters (the most frequently forgotten item in the anesthesia setup), which are used to clear the mouth of secretions, as well as the backup to the backup, a self-inflating Ambu bag. The first self-inflating resuscitator, the Ambu bag is a plastic bag that, when squeezed, pushes a breath to a desperate patient in need. When released, it pops back to its original shape, once again filled with air. It is the last-chance piece of equipment to deliver a breath when gas flow or the electrical supply has failed.
The Ambu bag was named by a Danish anesthetist in 1957. He never revealed the source of the name. The bag became so popular and successful that the developing company renamed itself Ambu. Possible explanations of the name put forth without much proof include the acronyms for “air mask bag unit” or “artificial manual breathing unit.” But in Danish—the company is based in Denmark—the word for “air” is luft. Not long ago, I spoke with representatives of Ambu. I pulled them aside in a meeting and asked if they knew what “Ambu” stood for. The answer? “Ambu” is an abbreviation of “ambulance.”
Once, on the first day of a new resident’s rotation, I demonstrated my method for anesthesia preparation, step by step. “Simply look at every drawer of the anesthesia cart before every case, and no step will be missed.” The next day, this resident was scheduled to work with my mentor-turned-colleague, a person I referred to as the “Learned One,” easily the brightest of my colleagues. I knew my old mentor’s teaching style and the questions he asked. After all, he had taught me. I told my new resident that the Learned One would simulate a breathing-circuit disconnect—“What happens when the machine alarm sounds for the patient not receiving any breath?” he would ask—and I demonstrated what to do: when asked, immediately reach into the bottom drawer and retrieve the Ambu bag. I opened the bottom drawer and—“Damn it!”—the Ambu bag was missing. I’d screwed up.
I found a replacement, then stressed to the resident not, under any circumstance, to let this happen.
Completing the trip along the circumference of my circle, at ten o’clock a pole rising from the floor to six feet tall has hooks that hold the bags and tubing for the IVs I use for infusions, as well as the drugs I administer during the case.
My work space looks like a little canyon, my nest.
TO PREPARE MY COMMAND CENTER, I start by connecting the airway circuit and move clockwise to the machine, ending at the cart. I quickly run my eyes from the top to the bottom drawer to ensure that every component of my anesthetic plan—Ambu bag for sure—is in one of those drawers. With one last scan, it’s time to go.
There’s one last item in my setup: the mother of all drugs, the resuscitator extraordinaire, the last-ditch effort to retrieve a life trying to end—epinephrine. It deserves a special place in my anesthesia nest—a place I call the “Oh Shit Shelf.” It’s on top of the anesthesia machine, immediately to the right of the flat-screen monitor. Whenever anyone in the room says “Oh shit,” I reflexively reach high and to my right, and grab the only syringe ever placed there, the epinephrine. I am the ultimate patient advocate, and my first thought jumps to a patient in jeopardy. Epinephrine is the single strongest heart-kicking drug I have. It bumps a slowing heart rate and increases a sagging blood pressure. Along with oxygen, epinephrine is the anesthesiologist’s life preserver.
One measure of an anesthesiologist’s expertise might be how often the Oh Shit Shelf is accessed. Many variables beyond the anesthesiologist’s skill affect the likelihood that epinephrine will be needed, including the nature and intensity of the procedure, the skill of the proceduralist, and the health of the patient. But the true measure of expertise is the ability of the anesthesiologist to manage a patient’s airway, to ensure the unobstructed and rhythmic flow of breaths in and out of the patient. The first step in any critical event is to ensure that the patient is receiving adequate breaths. The paradigm is rigid: ABC—airway, breathing, circulation.
The goals are simple: rely on skill, not l
uck; eliminate critical incidents; and never need to use the Oh Shit Shelf.
CHAPTER 3
The Five A’s
THE FIRST TWO HOURS OF MY LIFE AS A PHYSICIAN began at 8:00 a.m. on the first of July many years ago, in a lecture room with the other starting trainees in surgery. We were listening to advice—demands—on expected physician behavior, on completing medical charting in a timely manner, and on the benefit of the Office of Graduate Medical Education (that papers claiming medical malpractice would be delivered in the office and not on the floor in front of colleagues and patients). At 10:00, I was sent on to begin my practice of medicine.
By serendipity, my first rotation as a surgical intern was on the anesthesiology service. I approached the OR control desk and was greeted by the anesthesiologist charged with running the schedule for the day. At the traditional beginning of the educational year in medicine—for many physicians the first day of providing care—while the new anesthesiology residents were still attending lectures on patient care, I was released to tend to my very first patient.
“Your first case is waiting outside room 6,” said the anesthesiologist in charge.
I wanted to ask him: “Are you sure you know what you’re doing?”
During med school I rotated on the anesthesia service as an elective. I took it for the several hundred dollars it paid, money that I immediately dumped into stereo speakers and Bruce Springsteen’s Born to Run.
In the hallway outside OR 6, an eighty-plus-year-old woman with a hip fractured by a fall rested on a gurney, unaware of the significance of the date. She had no idea that she would be my first patient. Fortunately for me, someone else set up the anesthesia equipment, since I had never set up a room. I didn’t comprehend the concept of the command center yet, or the importance of the Oh Shit Shelf. One cursory swipe with my eyes and I decided it was time.
After transferring this unsuspecting woman to the procedure table and positioning the monitors, I pushed part of the contents of the big syringe—she was so small I needed to lessen the dose for her safety—and some of the small syringe, and turned the vaporizer to the right. Now this woman’s breathing became my responsibility. I applied the anesthesia mask to her face, squeezed the bag, and watched her chest rise and fall, the gases freely entering and leaving her lungs. Then I took a deep, relaxing breath myself.
“Go ahead,” my supervising anesthesiologist instructed, referring to intubating the patient. Truth be known, during my rotation as a student I had not once intubated a patient without assistance—plenty of assistance. I grabbed the laryngoscope, similar to a flashlight, with a battery pack inside the handle, leading to a metal blade with a light at the end. I scissored her mouth open with my right thumb and index finger; slid the blade into her mouth, past her tongue, and beyond the tonsils; lifted the handle; and for the first time ever looked upon those pearly white strips on either side of the voice box, her vocal cords, and slid the plastic endotracheal tube into the trachea. I squeezed the bag on the anesthesia machine filled with oxygen and the anesthesia gases, and sighed relief when I watched my patient’s chest rise with the breath I delivered. I used my stethoscope and listened to the air flow in and out of her lungs. I had complete control of her breathing.
The big syringe, the little syringe, and two clicks to the right. That’s the concept of an anesthesiologist’s work: the generic recipe for general anesthesia (not including one syringe to be given later—pain relief). The procedure for general anesthesia is to push into the IV the contents of the big syringe (twenty milliliters, or a tablespoon and a third, of a rapid-acting anesthesia medication, the drug that induces the loss of consciousness); then to push the contents of the little syringe (five milliliters of a paralyzing medication); and finally, to add a gaseous anesthetic to the inhaled gases by turning the dial on the vaporizer two clicks to the right to keep the patient anesthetized. It’s a little demeaning to my ego, but it’s often just this easy. Behind the simplicity of the recipe is a complex mix of aims, drugs, and techniques that extends anesthesia care beyond the actual anesthesia procedure, including pre-anesthesia patient preparation and postprocedure pain relief.
The term “anesthesia,” which means “without feeling,” doesn’t adequately encompass all of the goals of care. Since the discovery of ether, many adjunct medications have been added to the anesthesia gas to accomplish all-inclusive care. The effects that these side medications produce are what I call the “Five A’s of Anesthesia”:
• Anxiolysis, relieving stress created by an upcoming surgical procedure
• Amnesia, preventing memory formation during anesthesia care
• Analgesia, relieving pain during the procedure, but also considered beyond the procedure room to include postprocedure pain relief, acute (trauma) pain relief, and chronic pain relief
• Akinesia, preventing a patient’s movement during a procedure
• Areflexia, stopping adrenaline surge and swings in blood pressure and heart rate while under anesthesia
ALMOST ALL PATIENTS EXPERIENCE anxiety before a procedure. As the twentieth century began, newly developed barbiturates aided in comforting patients approaching surgery. The introduction of Valium (diazepam), in 1963, created a surge of anxiolysis research and use. Over 150 million prescriptions were written for the Valium class of antianxiety drugs (benzodiazepines) in a single year’s time.
Valium, and its short-acting younger sister Versed (midazolam), effectively lyse the anxiety that builds as the patient approaches the double doors. Acting within moments of intravenous injection, the drug paints the face of the receiver with a drowsy, intoxicated appearance. For adults, these “azepams” (as benzodiazepines are known colloquially) have been an anesthesia game changer for the first target of the Five A’s, anxiolysis.
Unfortunately, children still await the arrival of a suitable drug. Most children are not given, nor will they tolerate, an IV prior to the induction of anesthesia. This constraint necessitates less invasive and more suitable routes of delivery. Starting an IV in a child is a guarantee for two minutes of crying, while the induction of anesthesia by gas takes no longer, and usually less—twenty-seven seconds by my last measure. To date, no drug has become an acceptable and effective anxiolytic for children, leaving psychotherapy (otherwise known as nonstop distraction) as the alternative. (Thank God for iPads. I remain stunned by watching a two-year-old who is not able to talk nevertheless slice watermelons on the screen with the swipe of a finger.) The syrup of Versed is used with some success, but in short cases it is associated with increased anxiety on emergence from anesthesia.
Today, there are over thirty azepams to choose from, including the sleep-inducing—and sometimes sleepwalk-inducing—Ambien and Rohypnol, street-named “roofie,” otherwise known as a date rape drug.
AMNESIA, THE SECOND OF MY FIVE A’S, is a natural extension of anxiolysis, since many of the stress-reducing drugs, in higher doses, induce a lack of recall. Anesthesia is lost time. There is no memory. From the moment anesthesia is induced until that point in emergence that awareness returns, a gap in time forms in the existence of the patient. If memories enter the brain during this time—debate exists as to whether the anesthesia experience prevents memory formation or memory retrieval—they never come to mind when awareness returns. The benzodiazepines help form that time hole. The drugs I use deny the formation of new memories but leave past memories intact.
Amnesia is easy to achieve, and easy to screw up. At the concentration of anesthesia gas that allows surgical stimulation, amnesia is complete. The effects of anesthesia wear off gradually, as compared to the time required for induction, and the return of memory might not be all at once. Activity, especially voices heard in the recovery room before memory restoration is complete, might be construed as having occurred in the procedure room and during a procedure. The concentration of anesthesia gas needed to prevent memory formation is much less than that required for surgery. Ensuring amnesia is easily achieved by including at least
half the surgical concentration dose of the all-in-one potent anesthesia gas. Not all patients are able to tolerate anesthesia gas, and sometimes additional medications must be used. In such cases, amnesia must be a specific goal of the anesthesiologist, with medications for that purpose provided, or redosed if the procedure might outlast the actions of the amnestic drug.
Recall of events during anesthesia is possible when medications used to eliminate patient strength are not reversed in a timely fashion, as the patient is passing through a light level of anesthesia on the way to alertness but unable to react because of weakness. The patient hears everything.
Historically, anesthesia provided only calmness, and it was not uncommon for patients to be able later to recite every word spoken during a procedure. They were comfortable and relaxed and didn’t complain. This was in an era prior to my career. Now, with amnesia an accepted and fundamental part of an anesthesia procedure, the routine expectation is that no patient will remember what is said and done while under anesthesia.
But I know of two patients whose memory of specific occurrences during anesthesia convinced me that they did experience recall. One procedure resulted from a displaced clamp on a large artery that caused an immediate massive blood loss. The depth of anesthesia was decreased in an effort to prevent depression of the heart’s function—the gaseous anesthetic agents are known to lessen the pumping ability of the heart—and loss of blood pressure. After successful resuscitation, the patient remembered the event. Such recall is a form of locked-in syndrome, in which receptive capability remains fully intact but there is no ability to communicate.
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