Emma Shi

Under Anaesthetic

Before I walk into the room, I whisper an apology to my body for what’s about to happen. Then I step forward, into a space full of people wearing blue and standing under bright lights that are almost white. A doctor smiles at me, but the smile is muffled into something shapeless under his blue mask. He tells me to lie down on the surgical bed and I do as he says, then start breathing deeply. I count every second that I take in air, and then every second I let air out again, my breaths slow and measured.

After my third cycle of this inhalation and exhalation, a nurse walks up to me. The fabric around her mouth asks me how I’m feeling. I tell her I’m okay, but once the words are out in the air I want to take them back, hide them in my head for some other time when I mean it. The nurse tells me to think of somewhere warm, so I think of winter with the heater on high and hot chocolate and my mother. I am so deep in the memory, a memory full of blankets and soft hands, that I almost forget what’s about to happen. But then I feel the sharp, real prick of a needle in my arm.

This injection is the start of induction, and the beginning of general anaesthesia. General anaesthesia involves a mixture of different drugs and steps, and it starts with an injection of propofol. As they pump propofol through the needle and into my body, the cold rushes back all at once, washing the warmth of my imagined scene away. Too tired to reach for the memory again, I lie there and let it drift off into the distance.

This IV induction happens in the same amount of time it takes for blood to travel from the needle to my brain. So it’s a quick process that only takes around thirty to sixty seconds. Since most induction chemicals wear off quickly, the nurse is already starting to prepare me for the chemicals that will keep me stable throughout the surgery. Maintaining the anaesthetic through an IV is possible, but not ideal. This is because the only induction agent possible for IV is propofol, and monitoring the concentration of propofol in blood is a difficult task. Variables such as age, weight, height, and blood concentration need to be carefully controlled and calculated.

Inhalational anaesthetics are the most effective way to maintain general anaesthetic. This is because the concentration of these chemicals in my body can be easily measured. So instead, the nurse places a mask over my mouth, a transparent plastic that seals tightly against my skin. The initial cons of inhalational anaesthetics will no longer be relevant when I’m unconsciousness, since I won’t be able to taste or smell the pungent vapour that I’ll be breathing in.

Through this mask, I will be switched to an inhalational agent that will keep me under general anaesthetic, such as ether or chloroform. It feels strange to speak with a mask over my mouth, like it’s catching and keeping every word I say. The nurse looks down at me and I feel her hand on my left shoulder, close against my neck, where they’ll soon make an incision. I try to level out my breathing again as she softly says to me, don’t worry. I’ll make sure you wake up.

But I wonder how much she means it, and how sure she can be of it. Before I was brought to the surgery room, I found myself sitting in a small space where doctors and nurses came in and out, introducing themselves, telling me what was about to happen. I felt sick and strange with the thought of it. When I was given a consent form, I signed my name at the bottom even though my eyes only lightly touched over the words I saw. I didn’t want to imagine them happening, and so I let those words float in and out of my mind. It covered both the small effects that patients feel every day, in hospitals around the world, to extreme complications.

It is true that general anaesthetic can kill. Human error is always a possibility. General anaesthesia involves administering six to ten separate drugs, most of which are indistinguishable colourless liquids. It can be difficult to administer these chemicals together correctly, especially if the process is rushed. But the risk of death is extremely small. The decline of a patient under anaesthetic is a gradual process, and so an anaesthetist would have enough time to revert it. Based on an analysis of 4.1million surgeries carried out in the UK NHS, a 2006 paper showed that the overall risk of death from patients who undergo planned surgery is about 0.44%. In emergency surgery, this risk rises to 5.4%. But complications happen mostly due to other factors like pre-existing health problems, rather than the anaesthetic itself.

So perhaps the nurse’s promise isn’t too hard for her to keep. But there are other stranger things about anaesthesia that would be harder for her to measure, such as my level of awareness. A small number of patients have claimed that they remember moments from their surgery despite being deeply under general anaesthesia. They cite things like snatches of conversation, sensations of pressure or pulling, vague impressions of people moving around, and dreamlike experiences. But these moments of awareness are not necessarily painful. One study suggests that only one-third of patients who experience awareness recall any pain. A further 2007 study investigated over 87,000 patients, and found that only 1 in 14,000 patients undergoing general anaesthesia experienced any kind of awareness. More often than not, patients stayed unconscious the whole time.

But what about me? I think. But before I can delve into this question any further, the nurse asks me to start counting down from ten. As the propofol floods through my bloodstream and into my brain, a steady drowsiness spreads through my mind, turning everything I see into a vignette. All I can do is watch as my thoughts are washed in and out of the incoming tide of anaesthetic. I don’t know what place these chemicals will take me away to. I don’t know if it’s a warm one like the one the nurse is telling me to imagine. The world is smudging before me but I can still speak, so I count down from ten as they tell me to: ten, nine, eight. I don’t even make it close to zero.

It feels like a deep, deep sleep, with no dreams or tossing or turning or waking up in the middle of the night. General anaesthesia is unique because it renders me completely unconsciousness. Local anaesthesia, on the other hand, only makes a certain part of the body numb by interrupting certain nerve functions. Local anaesthesia would not make me unconscious like general anaesthesia does. During my surgery, many other drugs are also given such as painkillers, muscle relaxants, antibiotics, and intravenous fluids in order to replace body fluids that are lost during surgery. These are used to keep my heart rate and blood pressure steady. The anaesthetist monitors all of this while I drift away.

From the outside, it definitely looks like I’m asleep. My breathing is slow and regular, and my eyes are closed and unmoving. But it’s not quite the same. Electroencephalography, or EEG, is a process that measures the amount of electrical activity of the brain. It does this through electrodes placed on the scalp. EEG can also reveal differences in the brain between being asleep and being under general anaesthetic. EEG shows that during sleep, there is still a high level of ongoing brain activity. The EEG of someone in REM sleep has the same fast, low-amplitude, and high-frequency activity of the EEG of someone who is awake.

The EEG of someone under general anaesthetic is much more different. The overall power of this electrical signal declines, and the lights running along my brain would look like small sparks. There would also be moments of burst suppression, which are short instances of electrical silence. If I were placed under EEG during my surgery, my brain would be silent. These hushed landscapes are where patients like me are left floating through. The functions that are needed to create memories and experiences are temporarily gone, and for this reason, it is a state deeper than sleep.

Although a much more dire comparison, being under general anaesthetic is actually closer to being unconscious in a coma.So even though I look asleep, I show no response to anything from the outside, to the point that my body lets a surgical scalpel cut into my skin without any reaction. What would usually cause a reflex spasm in my muscle now leaves me as still and quiet as I was just after induction. The anaesthetic has suppressed my brain, the brain that taught me how to hurt, the brain that left me swallowing tears in waiting rooms.

General anaesthesia is a mixture of many different chemicals, and as a result, many parts of the functioning body and mind are affected. Muscle relaxants are another set of drugs used in general anaesthesia. They suppress any consciousness by paralysing muscles and taking away the possibility of pain. This includes both the physical experience of pain, as well as the emotional experience that follows it.

Pain begins with the triggering of receptors that are found in skin and organs. These receptors produce electrical signals of pain that are transmitted to the spinal cord and then up to the thalamus, a part of the brain that integrates these signals. Finally, these signals travel to the cortex, the surface of the brain. This is where pain is consciously felt, and where the hurt becomes real.

Analgesics, or painkillers, such as opiods, stop this pain from happening. They do this by blocking the pathways of these receptors, and therefore blocking these signals. If it weren’t for these painkillers, my nerves would normally let off flashes of pain signals to my brain. But under general anaesthesia, this circuitry is broken and as a result my brain does not receive the message. In this way, one of the worst feelings of human experience is simply wiped away.

A painkiller like morphine can also weaken the stress response of pain. This stress response is dangerous to a patient like me because it makes the nervous system produce adrenaline. Adrenaline prepares the body to respond to damage and to fight infection. The symptoms of this are sweating, trembling, a rapid heart rate, and rapid breathing. So this analgesic lowers the possibility of this happening.

Another group of analgesic drugs are anti-inflammatory drugs called NSAIDs. These stop the function of prostaglandins. Prostaglandins are compounds that respond to wounded tissue. By blocking prostaglandins, these drugs decrease the effect of inflammation, and my brain is no longer able to sense pain or the after effect of it.

Multimodal analgesia, which is the use of several different painkillers, is the best way of keeping patients like me free of pain. Combining an opiod, a NSAID, and paracetamol reduces not only pain but also the formation of painful memories. The anaesthetic pulls my body into a strange place where I do not remember, feel pain, or move. Hence the Greek meaning of the word anaesthesia: ‘without sensation’. The things I have known and accommodated my whole life—thought, pain, movement—are all switched off. The anaesthetic works deep into interiors and impulses that I could have never considered or imagined living without. And just like that, I am left there unconscious, awaiting and trusting the cut of surgical steel.

General anaesthetic drugs also limit the muscles between the ribs. For this reason, patients under general anaesthesia cannot breathe for themselves. Instead, they must be ‘ventilated’ by a machine through a breathing tube that is placed into the patient’s windpipe. An action that was once automatic becomes the complete responsibility of somebody else. So, taking general anaesthetic also means fully letting go and relying on another person. This further level of dependency, the need for someone to breathe for me, shows how general anaesthetic can truly render me powerless. 

But is pain still pain if I don’t feel it? If the pain signals never reach my brain and the hurt never becomes real in my own mind, then was it ever real to begin with? It makes me wonder what my unconsciousness has felt that I will never know. Although my body is completely dependent on the doctors around me, it is still definitely alive in some way. Despite all these drugs, and despite falling so deep into unconsciousness, my body is still able to continue functioning. As my thoughts fall silent, a part of my brain stays awake enough to keep my heart rate, temperature, blood pressure, and breathing stable. And even though I am unconscious, there are still inward signs that my body is registering that the surgery is happening. My heart rate and blood pressure increase, and my breathing becomes deeper and more rapid. In my bloodstream, the hormonal markers of stress response can be detected as well.

And even though general anaesthetic is a regular practice in surgery, what exactly happens during this process is still a mystery. In the mid-19th century, anaesthetic involved the inhalation of ether vapour. For nearly a century after the introduction of general anaesthesia, the process usually involved ether or chloroform, and sometimes a mixture of the two. The development of intravenous chemicals, muscle relaxants, and other drugs has resulted in a more complex and reliable system.

Despite this, not even anaesthetists completely understand how it affects consciousness. One aspect of how anaesthetics work is by affecting the communication between chemical signals and their receptors in the central nervous system. However, consciousness is such a vague term, and it is difficult to measure unconsciousness on a patient. Doctors can identify which parts of the brain are affected by general anaesthesia, but not how subjective unconsciousness plays out. Yet, so many patients fall into this strange unconsciousness thinking that they do.

There is no antidote given to reverse anaesthesia. Rather, when the surgery is finished, the anaesthetist stops administering the chemicals that have been suppressing the body and the mind. In this way, my mind is slowly allowed to return from unconsciousness. Propofol, as well as being an ideal chemical for induction, encourages a fast and clear-headed recovery. And as the anaesthetic fades away, the electric currents of my brain come back to life and I can be pulled back out from the strange place I’ve been inducted into. It is a place where doctors can cut open my skin, a place without pain, a place where I’m seemingly invincible, but also a place where memories seem so far away.

The nurse keeps her promise to me. And when I wake up, the first thing I hear is a voice. I am one of many who has been suppressed under general anaesthetic with no complications, and woken up with no recollection of the surgery. The last thing I remember is the short string of numbers I spoke just before I went under. Not even a snippet is left from what happened in between; the general anaesthetic has truly washed it all away. My eyes are closed and I, in that moment, do not know where I have been, but I know that I have lost something in the time I’ve been away. The brain that would not have let them cut into my body has just woken up, woken up from an unconsciousness that I let them trick it into. And I want to say sorry again.

But my heart remains beating and I breathe and breathe, and it seems to be enough for my mind, at least in that moment. I want to see who’s talking to me but my eyelids feel too heavy, like something sentient is pressing down on them. With each moment, I feel the pressure lighten a little. Eventually, it starts to release me and I am finally able to open my eyes. The world is getting sharper with each moment and I am beginning to see dimensions and shapes I recognise, familiar things that grow as my vision clears. Someone is standing there, telling me to take my time, to keep on breathing. The light is a lot less stark here, almost warm.

 

 

References:

Borreli, Lizette. “Going Under: How Anesthesia Works On The Human Body” (8 December 2015). Available at http://www.medicaldaily.com/pulse/going-under-how-anesthesia-works-human-body-364498.

Cole-Adams, Kate. Anaesthesia: The Gift of Oblivion and the Mystery of Consciousness. Australia: Text Publishing, 2017.

Dvorsky, George. “Why Anesthesia is One of the Greatest Medical Mysteries of Our Time” (19 June 2014). Available at http://io9.gizmodo.com/how-does-anesthesia-work-doctors-arent-sure-and-her-1592809615.

Gross, Terry. “You Won’t Feel A Thing: Your Brain on Anesthesia” (25 April 2011). Available at http://www.npr.org/2011/04/25/135516582/you-wont-feel-a-thing-your-brain-on-anesthesia.

O’Donnell, Aidan. Anaesthesia: A Very Short Introduction. Great Britain: Oxford University Press, 2012.

Perkins, Bill. “How does anesthesia work?” (7 February 2005). Available at http://www.scientificamerican.com/article/how-does-anesthesia-work/.

Przybylo, Henry Jay. Counting Backwards. United States: W. W. Norton & Company.

Storrs, Carina. “The Hidden Dangers of Going Under” (1 April 2014). Available at http://www.scientificamerican.com/article/hidden-dangers-of-going-under/.





Emma Shi

Emma Shi was the winner of the National Schools Poetry Award 2013 and the Poetry NZ Prize 2017. Her work was also included in Best New Zealand Poems 2017. She posts her writing at facebook.com/emmlexx.