'James, you need to breathe.'

I knew it was not an ordinary request. In a haze of anaesthetic and fentanyl, I thought I had done something wrong.

'Oh, yes,' I thought. 'I should do that. Sorry.'

But I couldn't. Had I forgotten how? I could not move. I could not respond. There was still the residual feeling of being told off, like a child, motivating me to try.

My thoughts turned to my mother and my father, and then to nothing. I could only spectate as my world went white.

My life did not flash before my eyes. I did not see God. There was just white.

'Oh well,' I thought. 'I guess that's that.'

I was in hospital to have my gallbladder removed. Ahead of time I had brushed off nerves and assured myself this was just another day in the office for them.

For me, I now accepted, it was not. Staff moved around the bed to help me where I could not help myself. Something was wrong and I was powerless to do anything.

But I was comfortable, indifferent to whatever muted commotion was going on around me. It was fine.

And then, like nothing had happened, I was back.

I had been told I could expect to be in recovery for about 20 minutes after the surgery, which could take an hour.

I sent my last text at 2:17pm and followed up more than three hours later, at 5:36pm. 

The interim was a blur. It felt incredibly efficient.

Before the surgery I had read all I could into what to expect, but I was still going into the unknown.

The anaesthetist talked me through the process and made gentle small talk as I was prepared to have my gallbladder removed.

And then, black. There was no count down from ten. I was fitted with a mask and thrown into darkness.

When I woke up, I was in a large, white ward. The row of hospital beds opposite indicated I was probably where I needed to be.

First observations: I am high. I was sober when I went in, and this is not a comfortable adjustment.

Second observation: there are four holes in my body.

I looked down and saw coverings over the places where my surgeon had dug around to take out the offending organ.

'Good,' I thought. 'It's done.'

It was quiet. Or maybe people were talking. It was hard to tell. There was a steady hum coming from somewhere, but it could have been the drugs.

My shoulders hurt and my stomach felt strange. A nurse came over to check on me and offered relief. It was a syringe of pale liquid I later learned to be fentanyl.

Slowly, the feeling of the anaesthetic wearing off took on a new dimension.

I swallowed the liquid and drifted off into catatonia. It was warm, fuzzy feeling, but hard to place against my reference of codeine and tramadol.

The only thing to focus on was the large analogue clock on the wall opposite. I tried to make sense of the time and work out how long I had been out.

No joy. Frustration grew. Surely I still knew how to read a clock. When was the last time I did? I was fixated on trying to solve something - anything - when the nurse came hurrying back.

'James, you need to breathe,' she said. 'You're not breathing.'

I hadn't noticed. I knew that was wrong and carried an implicit instruction. 'Wake up,' I thought. But I couldn't remember how. I couldn't respond. I could only think and continue staring at that stupid clock as people started to move around me.

There was no discomfort, no urgency on my part. The white of the room became steadily more vivid, like turning up the exposure on a photograph. My thoughts cleared.

Gasp. A had been fitted with a respirator to deliver oxygen. The cold of some foreign liquid ran through the cannula and into my veins. I was coming back.

There was another interlude of quiet before I mustered the strength to look around. The monitor by the bed was digital, but still made no sense.

The nurse said my blood pressure was coming down, but there was still more to do.

My brain may have been AWOL, but my heart was doing what it could to push oxygen around the body.

Some time later I stabilised and swallowed down a second dose of fentanyl. Again, there was a benign descent into indifference, a warmth and then silence. 

Again, I needed to breathe. Again, there was a respirator and people around me, and then life.

I felt much weaker the second time around, and my memory is less clear. I was monitored closely and staff exchanged notes on what had happened. 

I overheard that I had received two doses of fentanyl and some morphine. It was common in medical settings, they said.

I was not in pain. Depending on how it is taken, fentanyl is estimated to be 80 times as potent and morphine and hundreds of times more potent than heroin, according to the CDC.

In a medical setting, controlled and carefully measured, it is incredibly effective at its job. Opioid overdoses, a broad definition, are relatively straightforward to reverse.

Respiratory depression - breathing too slowly or shallowly such that carbon dioxide builds up in the blood, potentially leading to cardiac arrest - can also be treated with a number of mechanisms found in hospitals, including respirators.

I was probably fine, whatever was going on.  

But for the uninitiated it was an experience without parallel. It was hard to induce that I was probably fine. 

My understanding of fentanyl drew mainly from writing about the impact of street fentanyl in communities across the United States. 

Illicit fentanyl is often made in foreign labs and smuggled into the country cut with other illicit drugs to increase its potency. Drug dealers are also increasingly mixing fentanyl into other drugs - cocaine, heroin, methamphetamine - and fake prescription pills.

Dangerous combinations and inaccurate quantities present a real risk to users. Safe consumption rooms have been floated as a way to reduce harm, decrease public drug use and undermine black markets.

I started to reflect on this as I came to and made sense of what had just happened. I was safe. I was in the right place. Maybe I had dreamt all of it. 

I was fine, in the end. I went back to my room and vaguely recall the surgeon coming in to tell me the operation went smoothly.

It has been just over two weeks. The cuts are healing. The medication is decreasing. And I no longer suffer with my gallbladder. It was worth doing.

The feeling of not being in control has stayed with me. Again, for my doctors it was another day in the office.

But for me, I accept, it was unusual.

I do know that in those important moments, important as they felt, those around me did all that was required to make sure I was okay. 

They operated smoothly and professionally to help me through when I could not help myself. And for that I am grateful.