Introduction: Into the Blue
I am in a smallish, whitish room in a hospital in Brisbane. It is night. On the wall opposite my bed I can dimly make out a crucifix with its limp passenger. Beneath it float wide blank windows through which I watch the synapses of city light: a web of tiny illuminations and extinctions that seem, when I loosen my gaze, almost to form patterns; as if they are about to make sense. I am surprised at how calm I feel.
In the weeks leading up to this moment I have set my affairs in order, of sorts. Made a will, written letters for the children, waxed my legs. Said my farewells at the airport and boarded the flight from Melbourne with my mother. July 2010.
Some months before this, after decades of resistance, I gave in at last to the inevitability of major surgery. My capitulation was sudden and took place in a different wing of this same hospital, where I had come to consult a respected spinal surgeon. The surgeon had a quiet, almost diffident, manner and a moustache that put me in mind of a doleful Groucho. I am not sure what made my mind up, the moustache or the way his finger traced my wayward spine quite gently on the X-ray before him. But just as he began to tell me that I would not be a candidate for the type of non-invasive surgery we had been talking about, I realised with a small thud of certainty that, not only was I going to have this surgery-invasive though it might be-I was going to come back to Brisbane and he was going to do it.
In the aftermath of my decision, I was buoyed in a backwash of something like relief; a giving up of hope and its attendant efforts, a yielding to forces beyond my will. But when I lay awake at night, disquiet rose around me. It was not just the surgery that was worrying me-the cutting and drilling, the inevitable risk-it was that in some blank corner of myself I felt that I would not wake up afterwards. I knew logically, and during the day could convince myself, that for an otherwise healthy forty-eight-year-old, the likelihood of calamity was low. But at night, there in my bed in Melbourne, the conviction multiplied inside me that even if everything went according to plan, the me who woke after surgery would not be the same in some essential way as the me who had been wheeled into the operating theatre beforehand. I developed a dread of the moment when the anesthetic drugs would take effect and I would cease to be. I pictured myself in a stark, poorly lit room with two doors, one in, one out, neither of which I could open from within. Otherwise the room was empty. No windows, no furniture. In this darkness-which I now realise had the same sinuous quality as the shadows beneath my childhood bed-I would be trapped alone. Perhaps forever. At least until such time as someone else chose to release, not me but some other, ostensibly similar, version of me who would slip soundlessly into the life that had once been mine.
Shortly after making my decision I rang a separate Brisbane medical practice. I asked to speak to the doctor whose job it would be to render me unconscious and keep me that way during the long operation. Halting, almost apologetic, I explained to the receptionist that I had spent some years researching the process known as anesthesia, and that I was now rather nervous about what was going to happen to me. 'I think I know too much,' I said.
'Oh dear,' said the receptionist. 'That's not good.'
This book explores perhaps the most brilliant and baffling gift of modern medicine: the disappearing act that enables doctors and dentists to carry out surgery and other procedures that would otherwise be impossibly, often fatally, painful.
The term was appropriated from the Greek by New England physician and poet Oliver Wendell Holmes in 1846 to describe the effect of the drug ether following its first successful public demonstration in surgery. Anesthetise: to render insensible.
These days there are other sorts of anesthetics that can numb a tooth or a torso simply (or unsimply) by switching off the nerves in the relevant part of the body. But the most widespread and intriguing application of this curious craft is what is now known as general anesthesia. In general anesthesia it is not the nerve endings that are switched off, it is your brain-or at least parts of it. These, it seems, include the connections that somehow enable the operation of our sense of self, or (loosely) consciousness, as well as the parts of the brain responsible for processing messages from the nerves telling us that we are in pain: the neurological equivalent of shooting the messenger. Which is, of course, a good thing.
More than a good thing. I would not have boarded that plane for Brisbane had it been otherwise. And I don't assume my fears were greater than those of anyone else in my predicament. But it was also true that for the previous decade I had been deeply preoccupied with a question or series of questions, often nebulous and contradictory, that amounted to this: what really happens to us when we are anesthetized?
By this I mean not what happens to the pinging, crackling apparatus of our nerves and spinal cords and brains, but what happens to us-to the person who is me or the person who is you-as doctors go about the messy business of slicing and delving within us? And, fused somehow to this, another odd and stubborn question: can whatever happens (or doesn't happen) while we are under anesthesia continue to affect us in our waking lives? Can it change the way we feel or think or behave in the minutes, months and even years after surgery? Finally I wondered-a niggling, almost soundless irritation largely obscured by the first two questions-why did I care?
Not so long ago, if you were unlucky enough to need surgery and strong enough to withstand it, you would be tied down and cut open, usually conscious and probably screaming. Poppy. Hemlock. Hemp. Over the centuries healers tried every imaginable way of preventing or deadening pain: pressing on arteries, pinching nerves, soaking sponges in narcotic herbs for patients to breathe through. Some practitioners favoured a blow to the jaw; others rubbed stinging nettles on one part of the body to distract from another. Alcohol. Opium. Hypnosis. Prayer. Until the mid-1800s, surgery was almost always an agonising last resort. Most of today's routine operations were impossible, and even when they weren't, many patients chose death in preference. 'Suffering so great as I underwent cannot be expressed in words,' wrote one survivor. 'The particular pangs are now forgotten; but the blank whirlwind of emotion, the horror of great darkness and the sense of desertion by God and man...I can never forget.'
In the end a patient's best hope was often simply speed. A Napoleonic surgeon called Langeback claimed he could amputate a shoulder 'in the time it took to take a pinch of snuff'. The brutality of their trade made some surgeons wretched and others hard-hearted, but even amid the burgeoning humanism of the Enlightenment, pain was considered so integral to life that few could imagine surgery without it. 'To avoid pain, in surgical operations, is a chimera,' said the French surgeon Velpeau in 1839. 'Knife and pain, in operative surgery, are two words which never suggest themselves the one without the other...and it is necessary to admit the connection.'
Surgical anesthesia brought the gift of oblivion.
Yet 170-odd years after a Boston dentist named William Morton gave the first successful public demonstration-removing a lump from the jaw of twenty-year-old Gilbert Abbott-we still don't understand fully how anesthetics work. Each day specialist doctors known as anesthetists (or, in America, anesthesiologists) put tens of thousands of people like you and me into chemical comas to enable other doctors to enter and alter our insides. Then they bring us back again. It is mind-blowing. But quite how this daily extinction happens and un-happens remains uncertain. Researchers know that a general anesthetic acts on the central nervous system-reacting with the slick membranes of the nerve cells in the brain to hijack responses such as sight, touch and awareness. They have nominated areas and processes they know are important: the microscopic channels through which neurons blast their chemical relays; the electrical circuits that pulse and groove between different regions of the brain. But they still can't agree on just what it is that happens in those areas, or which of the things that happen matter the most, or why they sometimes happen differently with different anesthetics, or even on the manner-a sunset? an eclipse?-in which the human brain segues from conscious to not.
Nor, as it turns out, can anesthetists ultimately measure what it is they do.
For as long as doctors have been sending people under, they have been trying to fathom how deep they have sent them. In the early days, this meant relying on signals from the body; later, on calculations based on the blood concentration of the various gases used. More recently brain monitors have come on the market that translate the brain's electrical activity into a numeric scale-a de facto consciousness meter. For all that, however, doctors still have no way of knowing for sure how deeply an individual patient is anesthetized-or even if that person is unconscious at all.
I am not an anesthetist, or a surgeon, or even a doctor. I am, however, one of the hundreds of millions of humans alive today who have undergone a general anesthetic. It is an experience now so common as to be mundane. These days there are gases and vapours and chemical infusions. Drugs to knock you out, to wake you up, to make you lie still in between; drugs to take away pain. There are machines to measure your heart rate, blood pressure, oxygen level, brainwaves; machines to breathe for you when you cannot. anesthesia has become a remarkably safe endeavour: less an event than a short and unremarkable hiatus. The fact that this hiatus has been possible for fewer than two of the two thousand or so centuries of human history; the fact that only since then have we been able to routinely undergo such violent bodily assaults and survive; the fact that anesthetics themselves are potent and sometimes unpredictable drugs-all this seems to have been largely forgotten. An-es-thee-zha. Most of us can barely pronounce it. Yet it has allowed the body's defences to be breached in ways previously unimaginable except during warfare or other catastrophe. Through the use of powerful poisons, it has enabled entry into the secret cavities of the chest and the belly and the brain. It has freed surgeons to saw like carpenters through the bony fortress of the ribs. It has made it possible for a doctor to hold in her hand a steadily beating heart. It is a powerful gift. But what exactly is it?