A LAYMAN’S PERSPECTIVE OF CORONARY BYPASS SURGERY
Paul JasonTuesday, April 4, 2000, was the big day. It could be my last day if things didn’t go well in the operating room. I know that they were feeding me tranquilizers intravenously. Otherwise, I would have been bouncing off the walls.
At 9:05 a.m., an aide came to my room to get me. I was transferred to a gurney and brought to a holding area on the surgical floor of the hospital. The holding area was cool and I felt cold. A nurse put a blanket on me.
At first, the staff couldn’t find my surgical consent form. But soon it was located. A Physician’s Assistant came by to check my chart.
And then . . . a female physician with an Eastern European accent came. She told me that she was the anaesthesiologist. The anaesthesiologist?? What happened to whatshisname??
Oh, God! Is this a bad sign? A part of the team has been changed and we haven’t even started yet.
Again I expressed my apprehension, and requested that I be rendered unconscious before being brought into the operating room.
“No problem.”
Now, for the first time, I began to think about the paradox created by the fact that I had chosen my thoracic surgeon, but I apparently had no say in choosing my anaesthesiologist. What if my operation was about to be performed by the best cardiosurgeon in the hospital, assisted by the worst anaesthesiologist in the hospital? Why is it that patients get to pick their surgeons, but they don’t get to pick their anaesthesiologists?
Obviously, I didn’t have time to resolve that dilemma prior to my surgery. The tranquilizers were kicking in. Why hadn’t I thought about this before?
Anesthesiology is apparently one field of medicine (similar to obstetrics) that lends itself to group practice. I don’t know the history, the economics or the politics of this situation, but it is a fact. As I indicated earlier, I tried to interview two anesthesiologists after the surgery to get some answers to this and other questions. Perhaps, had they been willing to grant those interviews, I could be speaking from knowledge, rather than conjecture.
In my case, the surgeon was recommended by two of my attending physicians. Additionally, as I described elsewhere, I was encouraged by the recommended surgeon and by my cardiologist to obtain a second opinion and I did receive that opinion, regarding both my condition and my surgeon, from a cardiac surgeon affiliated with another major medical institution in New York City.
However, at no time during the pre-surgical process did anyone inform me that I had any choice whatsoever in the selection of the anesthesiologist. I repeat my earlier question: what if my surgeon is the best cardiothoracic surgeon at the hospital, but is being assisted by the worst anesthesiologist in the group providing services to that institution?
I knew that I would be subjected to general anesthesia during my surgery. But, what exactly is “general anesthesia”? Does it simply mean that they would “put me to sleep”? Obviously a general anesthetic state is much different from sleep. I can’t imagine anyone being able to remove or repair one of my body organs while I am simply asleep.
Actually, general anesthesia is about as different from ordinary sleep as a snooze is from a coma. It is essentially composed of four elements: hypnosis (unconsciousness), amnesia (lack of memory), analgesia (lack of pain) and muscle relaxation. Not every surgical operation requires all four elements. On the other hand, no one drug or technique can address all four elements at the same time. Therefore, being able to choose the correct combination of drugs and techniques is at the core of anesthesiology. Dosage, of course, is also important.
Amongst the drugs used to achieve the desired results are barbiturates, narcotics (opioids), volatile anesthetics, anxiolytics and muscle relaxants.
Barbiturates produce hypnosis and are used to induce unconsciousness. They provide virtually no analgesia, amnesia or muscle relaxation.
Narcotics or opioids, on the other hand, provide potent analgesic effects, but are not effective in producing either hypnosis or amnesia.
Volatile anesthetics are liquids that vaporize and are administered through breathing apparatus. They are very effective in producing hypnosis and amnesia and, at some dosages, produce good muscle relaxation. However, they provide no significant analgesia.
Muscle relaxants do exactly that. Therefore, they are never used alone.
In a typical surgical procedure, an intravenous infusion is established and an anxiolytic drug is introduced to calm the patient and to induce amnesia. In the operating room induction agents are introduced through the IV to quickly establish the anesthetized state. Most of these agents are short-acting. They are utilized to allow the placing of the endotracheal tube through the patient’s mouth, past the vocal chords and into the trachea (windpipe). Once this has been accomplished, the anesthesia for the surgery is begun by introducing combinations of the barbiturates, narcotics, volatile anesthetics, anxiolytics and muscle relaxants discussed above.
Interestingly, muscle relaxants, when they are used, are not selective, i.e., they weaken all of the muscles of the body, including the muscles used for breathing. That is one of the reasons the endotracheal tube is used. It provides a means of assisting breathing by connecting the patient’s respiratory system to an external, mechanical ventilator.
The anesthesia is continued until the completion of the surgery, at which time introduction of the agents is discontinued and the effects of the muscle relaxants are reversed with intravenous medications.
Most persons are awake enough to be responsive shortly after they arrive in the recovery room, even though they cannot remember these moments. The sensation of “waking up” occurs when the patient’s memory returns (the ebbing of the anterograde amnesia), even though he may seem, from all outward appearances, to be awake before that time.
Are there risks associated with general anesthesia? Of course there are, and we have all heard about them in some general way. A human being, with human frailties, will be making critical decisions regarding our lives while we are defenseless to fend off his or her errors. The number of potential complications are extensive. One source I came across claims that death, as a direct result of anesthesia, occurs about two or three times out of each million anesthetics. However, I wouldn’t take too much comfort in that statistic, assuming that it is true, because the emphasis is on death, as opposed to permanent damage to some body organ or system.
Another issue I had never thought about before is the possibility of waking up in the middle of the operation. I assumed, as I would think most other laymen have assumed, that once they put you to “sleep”, you stay asleep until the surgery is completed and you’re in the recovery room. Up until very recent years, while it was an exceptional occurrence, there were recorded instances when exactly that worst nightmare happened. To understand how it happened, one must appreciate the distinction between unconsciousness (lack of awareness) and amnesia (lack of memory). An inebriated person, for example, is not unconscious, but he could be amnesic. Therefore, in spite of the fact that his speech and motor coordination may be impaired, he can still be aware of his surroundings, although he may not later remember anything that occurred while he was in that state.
Are patients unconscious from the time that the initial sedation sets in until the surgery is over. Not necessarily. They may have no memory of the events that occurred while they were under the influence of anesthesia, but whether they were unconscious at all times is sometimes hard to tell. There have been some studies that suggest that many patients may have awareness, at least for sound, during anesthesia. It appears that very few have any recall.
During the surgery, as I discuss in the next chapter, the patient’s vital signs (pulse, blood pressure, etc.) are closely monitored. If there are any signs that a patient is beginning to awaken from the anesthetic, the anesthesiologist is alerted to this fact by telltale signs such as increases in blood pressure and heart rate, changes in respiratory patterns and a variety of other vital signs. Therefore, action can be taken to remediate the situation. Nevertheless, there have been cases where patients have actually experienced recall of events which occurred during anesthesia, even though above average doses of anesthetic agents were introduced or because their bodies failed to signal the telltale changes in their vital signs. Again, variable factors such as differences among individuals regarding their tolerances to medications can result in unexpected events.
The worst possible case scenario could occur when muscle relaxants are used. In that event if the patient becomes aware or feels pain during the surgery, he is incapable of communicating that to the operating team because he is essentially paralyzed.
Fortunately, however, in 1996 a new technology known as the Bispectral Index (BIS) became commercially available. It is a noninvasive monitoring system consisting of a sensor attached to the patient’s forehead and a monitor. It can directly measure the effects of anesthesia on the brain by analyzing the brain waves recorded in the electroencephalograph (EEG), translating them and producing readings on the monitor ranging from zero (no brain activity) to one hundred (the patient is fully awake). By continually indicating the patient’s level of consciousness during the surgical procedure, the anesthesiologist is able to adjust the amount of anesthetic agent the individual requires. The result is that there are fewer cases of under-sedation or over-sedation and patients are waking up faster after the surgery. I do not know if this device was used during my surgery.
To be continued next week…
