Lucid Dream Triggers / Triggering REM?

Previously I've experienced lucid dreams, one of which I've been able to pinpoint the trigger.

Since using CPAP I've found that the frequency of me having lucid dreams has decreased. This lends weight to my theory that some of them were caused by small-awakenings (micro arousals) due to aponeas.

As I'm left with a small residual AHI with CPAP it is still feasible that the odd lucid dream is triggered by the an aponea or hypopnea, although until now I haven't been able to accurately mark when the lucid dreams occur as they usually fade into conventional dreams when I lose lucidity.

However, over the past month I've had a couple of lucid dreams where I've been able to mark the ending via the CPAP machine.

Essentially what I did was wake from the lucid dreams and turn the CPAP off briefly for a couple of seconds. In the morning this 2 or 3 second gap in CPAP data was enough for me to locate the period that encompassed the lucid dream.

One such dream occured on a night where I consciously intended to lucid dream (although "consciously hoped" is more of an accurate description because all I did was get into bed and thought of lucid dreaming and hoped that this intent would somehow carry over into a dream later in the night and allow me to carry out a "reality check").

Because dreams tend to lack continuity, "Reality Checks" can help you to become lucid whilst dreaming. Occasionally I'll use a "reality checking" technique for a week or so. This involves doing somethng with a predictable result during the day such as:

Finger counting

If you count the fingers on one of your hands you know what the answer will be. For most of us it's five. However, if you do actually take the time to do this many times a day then you should find that when you next see your hands in a dream you'll have the instinct to count your dream fingers.

I tried this once in a dream: five. I was sure that I was dreaming, so I counted again: still five. I then did it again: six! Six fingers on one hand was definite proof that I was dreaming.

From that moment on I was fully lucid.

Light switches

Most of the time you go to switch a light on and it comes on. So next time you approach a light switch don't just stick your hand out and flip the switch, consciously do it. Feel the switch, feel it moving, hear and feel the click, then see the lamp illuminate.

I do this every now and then, and it filtered through into a dream. I stuck my hand out and reached for the light switch but there was just a flat square of plastic - no actual switch. Again this prompted me to question the reality of the situation and slip into a lucid dream.

On this night, it worked.

In this post I mentioned that I'd been on a trip to Manchester, well whilst at the station waiting for a train home I read a great book about Sleep Paralysis by Ryan Hurd. When I arrived home I was exhausted from an early start and ended up by having a lucid dream.

HOWEVER... the intent was not the only factor (and I suspect that it is only a small part) because on that night my sleep was interupted by a noise outside my house which caused me to wake up and remain alert for a while before sleeping again. The lucid dream then followed.

Something similar happened on the night that I consciously wanted a lucid dream...

Now that I sleep well with CPAP I generally don't wear a host of monitors such as the Black Shadow Monitor when I sleep, so I wondered if I'd be able to pinpoint the lucid dream using CPAP data alone.

I could.

Take a look a screen capture from Resmed's ResScan software from the night that I mentioned above (click for a larger version)

Looking at the top line (a whole night overview of my breathing flow rate in Litres per minute), you can see that I got into bed slept for a few hours, and was woken twice by my son for around 30 minutes, then I slept 15 minutes before being woken again, then I slept.

Now take a look at the detailed graph of flow rate. This graph covers the period outlined by two light blue vertical marks on the top graph (3:25am to 3:54am) you can see that something caused a large spike in my breathing. This was a noise in the house that woke me and made me lay awake to see if it was something to be concerned about. In the end it turned out to be something falling inside a wardobe (I'd "tidied" them that evening).

At 3:46am I entered REM and the lucid dream occured.

I suspect that intent is a reflection of awareness. After all, those who are are aware that it is possible to be aware in their dreams are more likely to become aware that they are dreaming, and this is a big factor is whether a lucid dream will occur however it is not the only one - for a lucid dream to occur (for me) sleep must be disturbed (creating a REM rebound effect) and the sleeper must also be alert and awake for a portion of the night (heightening awareness and self consciousness prior to entering REM).

Looking at the ResScan output you can see that my breathing was consistent with the regular breathing that occurs occurs during non-REM sleep. Then a large spike occurs (a large breath caused by me waking briefly to assess the noise), then sleep continues until I enter REM (where the lucid dream occured) before I woke (note the change in breathing pattern) before turning the CPAP off briefly to act as a marker for me.

It's curious that REM seems to occur so soon after being disturbed. I've seen this happen before with my son, and it makes me wonder if REM could acutally be triggered by a disturbance. 

In the following Zeo hypnogram from a night where I was monitoring my son's transcutaneous CO2 during a BiPAP titration you can see that REM occurs immediately after both times that I had to move the adhesive sensor (which disturbed him enough to briefly speak to me before falling asleep again and immediately entering REM).

So my experience, coupled with that of my son got me wondering about whether it was possible to actually induce REM sleep after a brief arousal and hence lay the foundations of a lucid dream).

Then this happened...

I'd had a disturbed night as I had been woken 5 or 6 times to attend to my son and we'd also all been woken by something hitting the roof of our house (probably a clump of moss). Then it began to rain heavily, so heavily that the sound of it made its way into my dream.

In my dream I could hear rain, but not see it. Then I realised that it must have been raining in the real world and that's what I was hearing. From then on I was lucid, and probably for the longest time so far.

I suspect that I was lucid for around 5 minutes. I explored the dream world and ignored the boundaries: I walked through glass windows into people's houses, I floated onto their roofs (maybe looking for the cause of the noise that had woken us earlier?), I floated down the road, going from house to house melting my face through windows looking for something. Then I floated all the way to the top of a tall building and decided to back-flip and somersault down to the ground.

It was as I was falling to the ground that I got the feeling that I was waking up. I kicked myself for doing something so stupid as triggering a falling feeling because the rush caused me to wake. I then marked the CPAP data as described and went back to sleep.

It's times like these when I wish that I'd been recording more data. Had I have been wearing the Black Shadow and the Zeo then I could really explore the data but it isn't practical to sleep that way every night just in case something odd happens.

If I can learn to reliably induce lucid dreams then I would wear all the monitors on a night where I tried to induce lucidity; the rain invading my dream has made me consider another way of triggering a lucid dream...

I've found an excellent website that sells mp3 of natural sounds without any music or talking over the top of them.

I plan to use ZeoScope to begin playing a thunderstorm when I hit REM sleep.

I'll post about how it goes soon.


Wild Camping with CPAP


Wild Camping (also known as Dry Camping) is where you camp with a minimum of kit using what you can find around you: drinking stream water, eating plants, hunting, trapping and building shelters (think "Ray Mears" and you'll get the picture - living with nature), and it's something that I'm taking an interest in, so much so that I decided to spend a few nights "under the stars", of course my CPAP machine came with me...

Why did I decide to do to do this?

Well, after an overnight power cut at home I realised how dependent we were on technology and electricity for pretty much everything we do, and that made me feel pretty helpless, it's all very well having the kit to treat my sleep apnoea but it becomes useless without electricity. My computers became black mirrors, my freezer became a box full of water, the hot water wasn't hot... anyway you get the picture.

It's all well and good having spare masks and tubing for your CPAP, but it's another to not have any electricity!

Fortunately during the power cut we had a car jump-start battery pack to power my son's BiPAP, but at his prescribed pressures it only lasts little more than a night. I began wondering how we'd cope with more than a day without electricity.

Yes, I could charge the battery from the car and risk it flattening my car battery, or I could let him sleep in the car while I drove us to a relative's house that had electricity, but that didn't seem to be a complete solution.

Although it's unlikely that we'd be without power for more than a day, it's better to be safe than sorry. How much easier is it to change over to battery backup than to go on a midnight quest for electricity?

This made me wonder how I would cope with a minimum of kit in the wilderness. I'd camped before, even in a desert in the Middle East, but that was with a 4x4 crammed full of kit and I wasn't a CPAP user then, travelling light was the plan for this trip, and the CPAP and Jump-Start battery pack were going to be an awful lot of kit to drag along.

So I invested in a relatively lightweight dedicated battery and tested how long it would support my pressures at home.

The "Super CPAP Battery" sustained my Resmed S9 Autoset machine for at least 5 full nights, so I knew it would last for my short one night stay in a woodland in Wales.

The idea of Wild Camping is that you take a minimum of kit with you, and it felt like cheating to be taking something as high-tech as my CPAP along but to be honest, I really don't like being without it now, so I decided that it was coming along. It would be my Desert Island Discs Luxury Item.

To try to cure that cheating feeling I decided that if I could charge my battery before I left using Solar energy then I was still qualified to play the self-sufficiency game without cheating.













Charging either of the batteries using Solar Power was simple and relatively cheap. I used a 13W solar briefcase from Maplin Electronics.

Camping aside, being able to do this gave me a sense of security, especially considering that if we were without power for more than one night I'd need a way to charge my son's BiPAP battery pack at home.

Of course I had other options, rather than taking the CPAP along for me. I could have slept on my side, but I wasn't keen on that as I often wake up uncomfortable in the mornings after using a side-sleeping device and I wasn't sure how well that would work if I ended up sleeping in a hammock. I could have taken 5-HTP but to be honest, I liked the idea of making a campfire and sharing a couple of whiskies around it with my brother, so that would likely negate the positive effect of the 5-HTP, besides, I know that alcohol has a detrimental effect on nightly AHI and hence I'd need CPAP more than ever if I drank.

I also wasn't keen on taking my shiny S9 Autoset into the woods for a night. I did contemplate buying a cheaper APAP to travel with but unless I did so and used it at home for a while I wouldn't trust the machine to behave in the same way as the S9 Autoset. 

Maybe that is something that I'll do if camping becomes a regular thing for me.

After putting a few more bits of kit into my rucksack we headed for Wales with the "Super CPAP Battery" charged full of English sunshine (yes, we have some every now and then). The sunlight had travelled 96 million miles, I'm sure it wouldn't mind another couple of hundred.

This is probably the point to confess that I packed too much kit. In hindsight there is much that I would leave behind as I didn't use it, and some things that I should have taken that I didn't (a sleeping bag being the major thing that I was pining for in the night).

One of the items that I took but didn't use (although I would have done had our stay been longer) was a fantastic piece of kit called Powerfilm. This is a flexible solar panel.

The panels come in many sizes and power ratings depending on how much electricity you need. Mine was the R-15 1200 which has an output of 15.4V and is rated at 1.2A 20W. This is more than enough to recharge the CPAP battery pack even in fairly overcast conditions...








On arriving in Wales our first port of call was a shop where we were able to buy some, eggs, whisky and gloves as the weather was already worse than the forecast had indicated. Oddly this made me remember a lucid dream that I'd had about being in Wales and left me wondering what the next night would have in store for me. 



We set up our camp in drizzle, so I made a simple shelter with an inbuilt groundsheet that would keep me and my kit dry.

In hindsight I should have sheltered in it until the drizzle stopped and then built something that offered more protection from the cold.



We took the Sawyer Point Zero Two water purifier with us, this filters everything out of the water that is larger than 0.02 microns. That means that all bacteria and viruses were removed. I suppose that you could use this to provide water for a humidifier, but I am so used to boiling water at home for when I used a humidifier that I'd still boil it anyway, not least because it would help with preventing limescale buildup in the humidifier tray.

Once the filter was hung from a tree we built a fire and I unpacked my CPAP setup ready for the night.

Fortunately the CPAP battery was more reliable than our fire (which lasted about 3 hours into the nighttime rain). The CPAP battery lasted all night despite it being cold (which I feared would affect it).






After a cold night I woke to find that everything (including me, the battery pack and CPAP) was covered in a heavy layer of dew and a touch of frost but it was still working. 






The other thing that I noticed was that a great deal of my kit had been slimed by a slug or a snail!

This night proved to be a good test of the kit that I'd taken but it also showed me where I was going wrong. I can assure you that the massively lower than predicted 4ºC felt awful during the night without a sleeping bag! 

For the following night we headed a couple of hundred miles south-east to Stonehenge for a night of hotel survival.

On arrival at the hotel, after foraging for the room service menu and having a nice hot shower, I realised that I wasn't prepared for the night because I didn't have the mains power lead or an extension lead with me to power the CPAP but fortunately the battery pack had more than enough power to last the night, and it meant that it could sit on the bedside table under the S9 leaving the room cable-free. 

So while the power-pack discharged its battery I was able to recharge mine...



This just goes to show how important a good sleeping environment is!





Waking up in the night to turn the air-conditioning on for some cool air and white noise was a far cry from scavenging around for dry wood in the cold wet night although the white noise of the nearby river and stream at our camp the previous night was vastly more impressive than the hum of the hotel air-conditioning...

... and it is that sort of natural feature that made me want to do this again but this time be better prepared. It was all very well reading about this sort of thing but it's another to actually try it. I'd made the transition from "Armchair Wild Camper" to a real life Wild Camper and wasn't going to give up now. After making a reasonable attempt the first time I decided to give it another go and put in place some of the things that I'd learned the hard way from the first night. So re-energised I removed some kit that I didn't use and packed some other things that I thought would be useful (including a sleeping bag and Trangia stove) then on my own at a new location nearer home set up my shelter in a more enclosed way.

Remembering the slug / snail trail, it occurred to me that the CPAP and battery combination may need a sleeping bag / hammock of its own. If it did nothing more than keep them slime-free then it would be worth it but it may also help with the problem of them accumulating a layer of morning dew by keeping them off the cold groundsheet.

I was concerned that whatever method I used would still need to enable decent airflow to the CPAP so I put the battery, adapter and CPAP into a string "turtle" bag and suspended it from the ridge line using a caribina but this could also have been achieved using a decent knot (something that is a real test of how tight you are able to make the ridge line because although the S9 is light, the power brick and battery aren't). 

In this photo I've lowered the side of my shelter to make the bag easier to see...

The string bag worked well because it allowed a good airflow and I was able to feed the CPAP hose through one of the holes in the bag. The bag was able to be moved along the line so that it was in a good position for when I went to sleep (not directly above my head, and not too near the edge of the shelter).


The bag helped a fair bit with the dew problem, although to be fair the weather conditions and my shelter weren't the same.

It would also be possible to wrap the CPAP / Battery combo in a lightweight towel before putting it into the bag as long as you were careful not to obstruct the air-intake of the CPAP.

It's also worth mentioning that it would be prudent to leave the CPAP machine safely tucked away until the smoke from your fire has subsided, otherwise every breath you take will smell of campfire smoke! 

I'll definitely do this again. As far as my bushcraft skills go, I've got a lot to learn but as far as the CPAP is concerned I'm very happy with how things went and have proved to myself that being tethered to a machine at night shouldn't put a limitation on activities like this. 


Blood Pressure and Sleep Apnoea

In this post I mentioned that my parents also have sleep apnoea and that my mother was going to have a CPAP trial.

During her trial we noticed something interesting...

Normally she takes medication to reduce her blood pressure, which has improved in recent years but still remains above normal.

On the mornings that she'd been using CPAP for the majority of the night, her blood pressure was lower, in fact it had dropped to a level where medication wasn't necessary.

She took three readings every morning from which we calculated a mean daily morning value. She did this for four nights before using CPAP and for four nights using CPAP.

The results are clear...




I've marked the limits for Hypertension as horizontal lines on the graph. Prior to CPAP my mum had systolic hypertension and borderline diastolic hypertension. Using CPAP she had neither and her blood pressure remained normal even until bedtime.

I would like to explore futher to see if there were any other factors that may have caused this, but just as when I began getting used to CPAP I felt it best to keep things simple and stress free, daily diet and other factors such as bedtimes were not monitored or compared.

My mum quickly got used to CPAP, but due to the fact that she sleeps prone, wasn't able to find a position that didn't cause the mask to dig into the side of her face in the night. 

We tried a few different masks, including the CPAP pro. Which she preferred over the Resmed Swift FX pillows because she grinds her teeth in the night (bruxism) and found that the moulded mouthpiece of the CPAP Pro prevented this, but ultimately she decided not to carry on with CPAP for the time being, although she said that the door remains open for the future should she feel the need. She also noted that on a couple of the CPAP nights her bedtime was later than usual due to her not feeling as tired.

It's hard to imagine the pressure that poor sleep, oxygen deprevation, high CO2 and the strain of apnoeas puts on the system, especially when it seems so normal to sleep this way every night but it becomes clearer to see when you have ways of quantifying it such as AHI and blood pressure.

That said, I've read about many people who are hypertensive and CPAP does not reduce their blood pressure. It could be that their hypertension is caused by other factors or maybe even that years of strain on the body through sleep apnoea has caused irreversible damage; I am not qualified to say, I can only speculate.


Additional Reading

Treatment of Obstructive Sleep Apnea with CPAP May Lower Blood Pressure




Travelling With CPAP / BiPAP


It's all very well making sure that your xPAP machine is set up nicely at home, in a good place beside your bed with the wires and tubing just how you want them, but it's another thing to get it right when you travel.

Over the years of travelling with my son's BiPAP and now with my CPAP coming along for the ride too, we've picked up a few tips that have helped - some of which we've learnt the hard way.



These are self explanatory. If you have a spare breathing circuit then take it with you when you travel. Yes, they take up valuable space in your baggage but that's better than wishing you'd packed them. They don't have to be new, you could take along an old but still functioning set that you have. 

I take our old masks and tubing and sterilise them before we travel. I'll make a post about how I do this shortly.



We also take a spare BiPAP machine with us. That has the advantage of being able to operate in BiPAP and CPAP modes (although sadly not Auto CPAP / APAP) modes, so it could serve as a backup for either of us.

A small roll of Duct Tape is a good travelling companion as it can be used to make on the spot repairs to punctures.


Extension Lead

Don't leave home without it! 

For some unknown reason many hotels seem to only provide one power socket in the bedroom and it's located by a desk across the room. This is useless for plugging your PAP machine into as it's so far from the bed. So you'll need an extension lead in order to prevent a night of sleeping up the wrong end of the bed and balancing the CPAP machine on a suitcase, or dragging the bed across the room towards the power point.


I use a 10 metre coiled lead (with thermal cut out and an earth "trip"). I always fully uncoil it when using it. It has 4 sockets on it, which is great as usually we need to charge a phone or a laptop overnight too.



If you use a humidifier, make sure you have suitable water to put in it. 

Cooled boiled water is good as the boiling should have killed any bacteria or viruses that were living in the water. 

One trip we forgot and the tap water wasn't suitable plus there wasn't a kettle to boil it in. So we went without the humidifiers and were pleasantly surprised at how different it felt to breathe.

Now neither of us use a humidifier, but we may appreciate some warm air when winter comes.


Bottled water (or even some home distilled water) is good to take along for the trip too, even if you get a 2 litre bottle and leave it by the bedside solely for the humidifier and rinsing your mask in the morning.


Travel Adapters

Essential if you are travelling to a place that uses a different power socket configuration. We use a universal adapter and plug our extension lead into it, giving us 4 UK sockets.

It's a good idea to check the fuse rating too, and avoid those "Shavers Only" adapters as their electrical rating isn't suitable. 



Battery Backup

 Call me paranoid, but we also take a 12v power supply and the appropriate leads for our PAP machines if we are travelling to a place where the power supply is temperamental. The battery can be anything from one of those car "Jump Start" packs to a dedicated CPAP battery such as the "Super CPAP Battery". The Super CPAP battery can sustain my Resmed S9 Autoset for at least 5 nights using pressures of 7.5 - 14 cmH2O. 

It's well worth doing some research into the type of battery that you are buying and calculate a rough idea of how long it'll last. Be aware that using a humidifier will draw more power from the battery, hence it won't last as long.


I'm going to be "Wild Camping" in a week or so (tentless camping in the forest) and I'm planning on taking my CPAP with me. (More about that in a post when (if) I return). (Edit - Read about Wild Camping with CPAP here)

A backup battery is a good idea, even if you aren't travelling. One night at home we had a power cut. I only realised because it became harder to breathe, but my son's BiPAP alarmed due to power loss, and his battery backed up Oximeter also sounded an alert. 

I was grateful that I had a battery (albeit a car jump charger) and a 12v lead for his BiPAP as his need is far greater than mine, he was back up and running in minutes, whereas I had to resort to side-sleeping for the duration of the power cut. 

My uncle (also a BiPAP user due to Post-Polio Syndrome) uses a battery backup all the time when travelling. His system switches to battery backup automatically if there's a power cut. The power supply where he travels isn't only prone to blackouts but it also suffers from "Brown-Outs" where the voltage isn't constant and dips or surges a lot, so his system protects his BiPAP from poor supply at the same time.


Other items that we've needed on our travels have been:

  • Fuses (for the plug)
  • A power brick transformer specifically for your PAP machine (the Respironics one packed up one night, so we used the one from the spare BiPAP)
  • CPAP Wipes

 The above items are things that I consider essential, although some only apply in certain circumstances. Each person will find the things for them that they consider essential. Some people use clips to hold the CPAP hose while they sleep, some use a dedicated holder, some will need a humidifier (and a spare) and I dare say that there are other things that people use that I haven't even considered.


100 Nights of CPAP



I've now been using CPAP for 100 nights and am very happy with it.

There have been a couple of nights that for some reason I put it on when I went to sleep and took it off a couple of hours later in my sleep. I'm still puzzled as to why I did that, because other than a vague memory of thinking it was morning I don't remember much about those nights.


A few brief points:

I haven't taken any sleep supplements during this time

I've only had two lucid dreams (and a couple of pre-lucid moments but woke up)

I've not had any episodes of sleep paralysis

I've still had hypnagogia every night


I love to sleep in a cold room and usually have a fan pointing directly at me, so I am also considering buying one of those hose-socks that is designed to prevent "rain-out"(condensation) in the hose. Even though I don't use a humidifier I do find that if I sleep in the path of my bedroom fan that I get a lot of condensation early in the morning which is unpleasant. I suspect that insulating the hose from the cooling effect of the fan would prevent this.

My data for these 100 days is good. My residual AHI peaks at 1.1, but most of the time is below 0.5 - even on the nights where I've consumed alcohol. 

I did have two nights where I deliberately didn't use CPAP as I'd agreed to test a sleep monitor for a hospital and gather some sleep data using it. I have to say that half way through the first night I considered stopping the monitoring and putting the CPAP back on because I woke myself snoring a few times in the night and had a few of those "throat closing" episodes, however, I carried on. By the second day (when I delivered the machine back to the hospital) I was tired and managed to fall asleep just before 5pm for a short 20 minute nap before waking and staying awake until 8pm where I slept through on the ward until 8am the following morning.

On the mornings after not using CPAP I had a sore throat and felt a bit congested. This is something that I'd become used to in my pre-CPAP life. On the second morning I woke with a headache - this too is something that had become a regular occurance and my morning routine used to involve stopping off at a shop on the way to work to buy lunch, and a couple of times a week I'd buy paracetamol.

The irritating thing is that my own ignorance (and that of the doctors that I spoke with) meant that my symptoms (headache, sleep paralysis, hypnagogia etc) weren't considered together and instead I was given a CT scan and painkillers for the headaches along with antidepressants for the sleep issues - although to be fair this was 15 - 20 years ago and sleep apnoea was even less known about than it is today.

Although awareness, diagnosis and treatment of Sleep Apnoea is good in those groups of patients considered to be at higher risk, I do still wonder how many community doctors would consider sleep apnoea as a diagnosis for some conditions in the general population.

I know that I only have mild - moderate sleep apnoea and I know what a huge difference CPAP has made to me, I can only imagine what the change will feel like for people with more severe apnoea.

I'll definitely be staying with CPAP. It's travelled well with me from home to hotels, to hospitals, to foreign countries and soon wilderness camping!