Anesthesia, page 23
It’s lovely stuff—Damasio writes gorgeously—but it’s probably not much help to working anesthesiologists: they tend to regard wakefulness as a bad thing. With or without an attendant self.
Some researchers have, nevertheless, hedged their bets and proposed a sort of almost-anesthesia. A good-enough version, in which patients may be wakeful without being considered aware. Britain’s Jaideep Pandit posits a state he calls “dysanaesthesia.” (“Patients in this state can be aware of events but in a neutral way, not in pain, sometimes personally dissociated from the experiences.”) Definitions waver and drift, although doctors who think about such things tend to link such experiences to lighter anesthesia such as you might experience toward the end of surgery while being stitched up, or near the start when the breathing tube goes into your trachea.
In the end, however, the Canadians Merikle and Daneman concluded that despite the “remote possibility” of some people experiencing moments of awareness during anesthesia, it was reasonable to assume that patients were unconscious. “It seems improbable that patients have experiences during anesthesia that are similar in any way to the subjective experiences normally associated with conscious perception of external events. Thus a reasonable working hypothesis is that patients are unconscious during surgery.”
Ian Russell maintains the hypothesis is flawed.
In the absence of the isolated forearm technique, he argues, some of the studies supposedly demonstrating that people can form hidden memories while they are unconscious instead prove the opposite—that patients are frequently awake and sometimes in pain on the operating table but cannot remember later. He includes in this critique studies that have relied on EEG-based monitors to guide the anesthesia. In mid-2006, to prove his point, he published a new study using the IFT in conjunction with a commercial depth of anesthesia monitor, the Narcotrend, which, in addition to presenting the raw EEG, analyzes brainwave activity and then converts the data into numbers and graphs representing the stages of anesthesia. The study looked at twelve women having gynecological surgery with muscle relaxants. Russell adjusted the amount of anesthetic each woman received according to the feedback from the monitor. Once again he played each woman a tape that included his voice asking her at regular intervals to open and close the fingers of her right hand. Unlike the earlier experiment, all but one of the women had also been given an epidural nerve block to prevent pain. But the results were again startling. All twelve patients responded with their nonparalyzed hand at some point during surgery despite the fact that on more than half these occasions the numeric readout either showed them to be at surgical levels of anesthesia or was blank. Patients seemed to dip in and out of consciousness, sometimes responding in apparently deep anesthesia but not at lighter levels. Again none of the women said they remembered the experience, though in interviews afterward some recalled Russell’s taped instructions.
More recently, Russell has staged similar experiments using the IFT alongside the BIS monitor. While the number of women who responded dropped to one-third when staff used an inhalation anesthetic, another study using an intravenous drug showed that during BIS-guided surgery, nearly three-quarters of patients still responded to command—half those responses within the manufacturer’s recommended surgical range.
Russell is an admirer of the BIS, which he considers a useful tool, but his concern about brain monitors more generally is that the complex algorithms on which they are based tell the anesthesiologist only the probability that a particular patient is asleep at any single point, and cannot account for the natural variability between patients.
Unsurprisingly, Russell has his own critics. Debate ricochets back and forth over the IFT’s alleged technical limitations and what some see as its potential for distraction or even disruption during surgery. The manufacturers of the Narcotrend sent me a long and cordial defense of the monitor arguing among other things that Russell had used uneven and at times inadequate pain relief in the 2006 study—concerns that Russell has fiercely disputed but which were also raised about the studies using the BIS. Kate Leslie points out that Russell’s studies are tiny compared with the BIS study she and Paul Myles carried out, meaning his results might have arisen by chance. In the BIS experiments above, she notes, surgery took place when patients were at the highest end of the recommended range (higher, she says, than is normal practice) and sometimes above it. Even many supporters see the IFT primarily as an experimental tool.
This is not to suggest Russell is alone in his findings. A 2012 literature review by a fellow Brit, Robert Sanders, showed 37 percent of anesthetized patients responding to the IFT after “noxious external stimuli.” That said, the review only included thirteen studies, most involving fewer than forty patients, and five carried out by Russell himself. There have been no large-scale clinical trials to assess the technique or determine its benefits or risks.
But the other intriguing thing about Russell’s experiments with the Narcotrend and BIS monitors is the intravenous drug he chose to use: propofol. The same drug now coursing through Jenny’s bloodstream as the surgeon plucks and snips at her abdomen. Russell loves propofol. It is fast and effective. His patients wake up happy and refreshed. He remembers one woman complaining when he woke her, saying he had interrupted a nice dream. Propofol is like a little holiday. Unlike many anesthesiologists, Russell does not even combine it with a gas anesthetic to give him more certainty. He says he already has certainty. The problem as he sees it is not with propofol, but with the doctors who use it, many of whom, he claims, do so too sparingly. “Basically what is happening is you’re tying the patients onto the operating table with your muscle relaxants, and they may be awake . . .”
The operation is nearly over. The doctors are stitching Jenny’s abdomen. Russell starts to lighten the anesthetic (“. . . just given her a bit more relaxant because she was wincing slightly; her hand had moved slightly and her eyebrows . . . a slight wiggle.”) Now the BIS has dropped again and she has stopped “responding.”
“How did you know that was a relaxant thing and not an anesthetic thing?” I ask.
“I didn’t. I just thought she was, um, looking a little bit . . .” He glances at the woman on the table. “Here we go,” he says, with interest, and moves across to take her hand.
“Jenny, squeeze my fingers with your right hand.”
And this is the moment.
From where I stand against the wall, level with her arm, I watch her hand close firmly and unambiguously over his.
“That’s excellent. Wonderful. Now I want to know if you’re comfortable Jenny. If you’re comfortable, squeeze my hand twice.”
Her hand closes once more, clearly, purposefully. And again.
Like a message from a miner trapped far underground.
“That’s fantastic,” Russell tells her, “OK. Operation’s nearly finished. Everything’s going well.”
He moves away. The stitching continues. The BIS is back up to 64—above the ideal 40 to 60 range BIS manufacturers recommend for surgery, but within the accepted surgical range for these final stages of surgery, he says. He notes that under the protocol in Paul Myles’s and Kate Leslie’s B-Aware study, at this stage of the operation “they were letting the BIS drift up to 75 for the last ten, fifteen minutes of the surgery” before giving a reversal drug to counter the paralyzing drug. “And they said the patients woke up very quickly. A lot of the patients were probably awake already . . .”
Jenny’s BIS continues to hover around 65. Russell is relaxed. “She gave a quite clear indication that she’s comfortable.” Within a minute or so it is over. Jenny lies immobile on the trolley while staff pack up around her. The surgeon, a short pleasant man with a self-deprecating sense of humor, thanks the team. A few meters away, doctors discuss another case, a woman whose cancer has spread through her body. Any surgery, they say, would be palliative—to treat the pain, not the disease, which is now unstoppable. The doctors discuss logistics. There is some question about whether she is even fit for an anesthetic. I look back across at Jenny lying silently in the center of the room. I wonder if she too can hear what the doctors are saying, and if so what she might make of it.
The memory keepers
About three hours south of Sydney is a scoop of ocean called Jervis Bay. We used to go there for summer holidays. I remember loping down to the beach one Christmas morning with my sisters and Dad, when he could still lope; topping the rise to see a pair of dolphins, another; another; kinetic arches against the white blue. More recently I have visited with a group of friends, one of whom has a house there. Sometimes we drive around the corner from the main beach to a smaller, quieter one, a vivid jag between two rocky outcrops. The first time we went was the year of my back surgery. Everything hurt. My body was foreign. I was afraid of movement, of jolting, of metal snapping inside me and poking through. I moved like a stick figure, step by stiff step, across the narrow beach and into the slot of the sea until I was deep enough to sink. And then I let my legs loosen and rise until I was floating. Head down (goggled, snorkeled) slow-flying over the receding sandy floor, weightless, wantless, and all around me twisting lozenges of light. Whiting.
Sometimes when I am in the unbeautiful pool, when I put my head underwater and see darkening grout and nameless filaments, I say the words to myself (dappling, dappling) and slowly, magically, it is all there before me. Not the exact place, but an echo or overlay. A feeling. All light and depth and splinters of silver. Whiting Bay.
In the hospital, after her collapse, my mother woke morning after morning into a white room almost identical to the one in which she was actually lying. (Hooked to catheters and drips, a diffuse morphine wash.) This other hospital room looked the same but was, in some qualitative way, different. Mum was puzzled at how the same nurses appeared in both rooms. Narrowing her eyes. “It’s happening again.” Slippage. One night she dreamed of Brunswick Heads, a coastal town far from home. Had she ever been there, I asked, to the real Brunswick Heads? She could not recall. She thought she might have. Outside the wind thickened. In the night, she said, it sounded like the sea; perhaps that was why she was dreaming of the coast. “I think a lot of my dreams come from the sounds around me.”
Another hospital. Sydney, 1997. My father, delirious. Flailing. The previous day he had been admitted to a private hospital in Sydney for heart surgery. My parents drove from Canberra and I from the Blue Mountains. Afterward, my mother and I followed a nurse into the intensive care unit, where we found a row of four trolley beds lined up like baby carriages against the far wall. On each one, motionless against the starched hospital pillows, a pale sunken head: balding, fetal and to me disconcertingly similar. At first I walked toward the wrong one. Mum called me back and for most of the rest of the day we sat or stood on either side of my father’s bed as he made his ungainly, spasmodic journey toward consciousness. Like birth, like death, it took its time. Hauling himself out of his stupor, he appeared to recognize us and launched into a circular sort of conversation that was to continue for most of the afternoon. In between periods of mumbling and silence he would announce in tones of agitation that he needed to go to the toilet. One of us would explain to him gently and clearly what had happened, that he had had an operation, that the doctors had inserted a catheter so he could go whenever he wanted. Sometimes he would settle down for a minute, but at others would continue in increasing distress. “This is awful. I want out, Bridgey”—my mother’s name, Brigid—“I want out!” And then again: “I need to do a wee.” This went on for hours. Every few minutes one of us would explain again what was happening and he would subside. Minutes later he would begin the same refrain: “Bridgey I want out; this is fucking awful.” A few times he reared up and made to pull the tubes out from his arm and get out of bed, and the ICU staff would hurry over and press him firmly down. Some were kind. Some less so. One nurse spoke to him loudly as if to a stupid child, and then to us: “He’s not making any sense.” My mother and I thought he was making pretty good sense. Once a male attendant muttered that if this had been the public system my father would have been properly “restrained.”
Whether this would have been preferable to the practice, described in an 1834 edition of The Lancet, of treating postoperative delirium with a laudanum enema is hard to know. No one seemed particularly interested in why he was behaving as he was. His doctor told us my father had had a bad reaction to the anesthetic. The next day, propped up in bed, frail but recognizable, he remembered none of it.
He went on to recover fast and fully, at least physically, although I felt it was a long time before he regained his buoyancy. Years later, however, comparing this experience with his childhood surgery, he was very clear which he preferred. Of the earlier anesthetic he said:
There was a sense of suffocation. They put this thing, which presumably was soaked in the anesthetic, they put this over your nose and mouth. This is my recollection. I’m not being unkind about it. I’m not saying there was anything brutal about the procedure, but that was the procedure. Certainly there was this sense of suffocation. You did not want this to happen.
It wasn’t remotely like what happened to me last time [with the heart surgery]. You were all aware I wasn’t having a nice time. I wasn’t.
In the same edition of the British Journal of Anaesthesia in which Hull anesthesiologist Ian Russell reported patients squeezing his hand during surgery even when brain monitors indicated they were unconscious, there was an accompanying editorial by New York anesthesiologist Robert Veselis. I had first heard of Veselis through Melbourne’s Kate Leslie. He was “the memory guy,” she said, adding that she had once had lunch with him in Paris. “He’s sort of kooky but really nice.” The next time I came across him was in this editorial, “The Remarkable Memory Effects of Propofol,” in which, after praising Russell’s work, he went on to draw a completely different conclusion. What interested Veselis was not so much what the study said about the Narcotrend monitor—or indeed any other depth-of-anesthesia monitor—but what it confirmed about the drug propofol, which he said must now be added to the list of “prototypical amnesic drugs”—drugs that make you forget. Then, he went on to raise a rather startling question about the purpose of anesthetic monitoring. “[T]he question is whether we want a monitor to detect unconsciousness or one that detects amnesia?” As long as anesthesiologists could guarantee forgetting, he seemed to suggest, unconsciousness might be optional.
The article drew a swift response from Bristol anesthesiologists Khaled Girgirah and Stephen Kinsella. “It suits anaesthetists to tell patients that awareness is a rare complication, occurring in 1–2 per thousand,” they retorted in a letter to the journal. “However, this figure relates to awareness with recall. We thought that it might be less reassuring to tell them that they have a 16 percent chance of being awake during surgery, or even ‘you are sure to be awake for some of the time during surgery.’” (They were referring to Ian Russell’s studies using the isolated forearm technique.)
The pair then described a straw poll they had taken of sixty anesthesiologists in their own hospital. The question was whether they, personally, would find it acceptable to be awake during surgery, “even though you did not remember afterward.” Three-quarters said no. What about being awake and paralyzed, even without later recall? This time 93 percent said no. Asked, finally, would they be up for the trifecta—awake, paralyzed and in pain (albeit without any later memory of the experience)—the figure went up to 97 percent.
“We think that if most anaesthetists wish to be unconscious rather than amnesic during general anaesthesia,” Girgirah and Kinsella concluded, “it will be a long time before it is possible to convince the public that this is acceptable or desirable.”
I phoned Veselis in his New York home, which he at that time shared with his wife, four kids, four rescue cats and two rescue dogs. He seemed easy to like. In practice, he said, he was not suggesting that it was all right for patients to be in pain even if they did not remember it. Pain during surgery could, after all, set patients up for chronic pain later. Like many of the surgical staff I spoke with, Veselis acknowledged it was not unusual for patients to wake during surgery. (“People wake up all the time,” one intensive care nurse told me, “but we put them straight back again.”) Ultimately, though, he said, for patients whose pain was well controlled, periods of wakefulness during surgery need not be a problem—as long as they didn’t remember them.
“I think that most people seem to accept the fact that if the explicit memory has disappeared—or awareness has disappeared; you don’t remember—there does not seem to be as much concern about that . . .”
The greater risk was posed by over-medication. His point, he said, had been that in their attempts to ensure that patients could not complain of having been aware, anesthesiologists tended to give more anesthetic than they needed to. In reality, and with today’s clever drugs and monitors, it was no longer necessary—and could be dangerous—to keep patients that deeply drugged. “Unconsciousness is a good starting point, but a more refined consideration is that actually what we want is amnesia—that is really what we want.”
In an eloquent response to his Bristol counterparts in BJA, Veselis argued that current practice was driven by anesthesiologists’ “visceral fear of failure.” He recalled Horace Wells’s disastrous 1845 demonstration. The screaming patient. The mocking onlookers. “This untoward response to anesthesia rests heavily on our collective consciousness, and is reinforced with every new case of awareness.”
