CPAP - It's well worth taking the time to get it right

Previously I'd used CPAP for a few days to try to get an idea of how my son felt as he started to use it.

Initially I tried it in the hospital where it was prescribed. I used it whilst awake using a variety of masks and pressures to see what high pressures felt like and to see how it responded to me exhaling, holding my breath, trying to talk and opening my mouth etc. Then I used it for a few nights. I wanted to know what problems he could encounter because he isn't able to move to correct them for himself, so I thought that if I were familiar with some of the problems it'd at the very least give me a frame of reference for when he told me what issues he was having.

For practical reasons I purchased an additional CPAP (technically an APAP machine - Auto CPAP). I chose the Resmed S9 Autoset, which to its credit doesn't look like a piece of medical kit; it looks more like a modern bedside clock radio. Yes, the pressures should be set by a professional and you need a prescription to buy one but it looks like a piece of consumer electronics, which is a great thing because it doesn't make your bedroom look like a High Dependency Unit.

Resmed also make coloured "skins" for the device which would be helpful when trying to introduce it to children as part of their therapy.

The S9 has a coloured display screen which allows the user to adjust the comfort settings and climate control and to allow them to see an instant indication of whether the mask is fitted properly along with a morning readout of your AHI (Apnoea Hypopnea Index).

The S9 records overnight summary data and detailed data to an SD card, which via the ResScan software allows you to see the following data: 

• Respiratory Events via flags on the timeline (Central Apnoeas, Obstructive Apnoeas and Hypopneas)
• Pressures chosen by the machine at any given time
• An indication of snoring level
• Flow (allowing individual breathing waveforms to be seen)
• Leak
• Flow Limitation (an indicator of the degree of obstruction)
• Compliance data (how long I used it for)

An example of the data from one of the nights that my son used it is shown below.

All of this is very useful to have access to because it lets you see a record of the choices that the machine makes which helped me to trust that the machine wasn't going to deliver a high pressure unless there was a good reason to. This is all recorded automatically while you sleep at home (or in the sleep lab). Compared to a one-night study in a sleep lab (especially a split night study) the data may be a more realistic representation of your sleep because you'll be sleeping in a familiar place and adhering to your usual routine.

The output that we collected from the ResScan software was viewed by my son's doctors during his initial trials with CPAP before changing over to Bi Level ventilation (BiPAP / VPAP / BPAP)

I chose Resmed's Swift FX Nasal pillows as they left a lot of my face free, they didn't feel trapping and are easy to remove if I really felt like it in the night.

My son uses them with Bi-Level PAP and prefers them over a wide range of masks that he's experimented with, although he can't move below his shoulders he has learned to remove the Swift FX pillows by a head movement, so he feels comfortable using them as he knows that he can take it off if needed.

The S9 has an "AutoSet" mode where it can alter the delivery pressures as it deems necessary. The machine can be forced to work within a range of pressures. I decided to let the machine have a free reign and didn't force it to choose between limits. 

I managed to keep the CPAP on for most of the night, but I remember waking frequently and moving the tubing and to keep checking the machine because... well to be honest... I was nervous. The machine is very quiet which was another reason to check it every time I stirred in the night in case I'd managed to turn it off in the same way that I snooze the alarm clock. 

Over the few days I was tired because, as I said above, I'd been awake due to my own anxiety and the strangeness of it all, also I managed to get caught up in the tubing one night! The following evening I arrived home from work and dived face down into bed without CPAP. Due to my sleep debt over the previous few nights I experienced sleep paralysis and a lucid dream, so it wasn't all bad.

...and that's where my trial with CPAP ended.

However, recently I've fallen in love with CPAP and in particular Resmed's S9 Autoset (the photo above is my S9 beside my bed), and here's how it happened...

There's a lot to get used to with strange tubes and masks on you and your bed plus a new machine on the bedside table - and that's without getting used to the pressures that the machine delivers... considering this, my experience wasn't really a fair trial for CPAP, especially since it is considered to be the "Gold Standard" in treating obstrucitve sleep apnoea.

In hindsight, I suspect it would have been better to begin by choosing a low pressure and just wearing it to get used to the mask and tubing - almost a dress rehearsal before the therapeutic pressures are used.

My CPAP experience was well over a year ago and before the time that I started this blog and before the time that I realised that I had mild to moderate obstructive sleep apnoea. Now that I have a better understanding of my own sleep and have found various ways to reduce my AHI without CPAP I decided to give it another go and compare the results, after all we now had my son's "old" (barely used) S9 Autoset sitting in a cupboard doing nothing because he actually needed Bi-Level PAP.

This time I paid a lot more attention to my own AHI.

I also decided to eliminate the uncertainty of whether the machine was going to wake me with a high pressure during the night, so I did a gradual titration over several nights using the "Straight CPAP" setting of my son's backup Respironics BiPAP S/T.

I found myself making slow deliberate breaths while I tried to sleep. This wasn't particularly helpful, because (even if you aren't wearing CPAP) when you think about your breathing you find yourself consciously taking over, and to be honest this is something that our bodies do better if we don't let consciousness interfere with it.

However, I found myself calmly waking up every now then wondering why I wasn't breathing and finding that I had to consciously take a breath, I listened to machine respond, then dropped back off to sleep. This happened maybe 5 or 6 times that I remember during the night and wasn't anything like waking with a snort or a choke, in fact it felt quite strange. 

In the mornings I took a look at the data (the BiPAP S/T also records data to an SD Card that is readable via the Respironics Encore Viewer or Encore Pro software. 

I found an explanation for the breathless awakenings...

Whilst the obstructive apnoeas were few and far between, the machine had detected "Central Apnoeas". These are when the airway is open yet no air flows. This can be from a variety of causes, but from my own baseline sleep studies I know that my apnoeas are usually obstructive in nature, so I knew that these new Central Apnoeas were because my chosen pressure was too high.

If breathing is too effective at clearing CO2 from the bloodstream then central apnoeas can occur because during normal breathing the brain sends a signal to breathe when CO2 in the bloodstream reaches a certain trigger level. We then breathe causing gas exchange, (taking oxygen in and exhaling CO2), after which our bodies produce more CO2 which reaches the trigger level and the cycle begins again.

If the CO2 level is too low then the brain doesn't need to clear it, so doesn't send a signal to breathe. Our oxygen levels then drop which wakes us up and allows us to consciously take a breath.

I adjusted the pressure down by 1 cmH2O the following night, but I still wanted more data. Were these really "centrals"? A night wearing the Black Shadow Sleep Monitor whilst on CPAP confirmed that they were.

I switched machines back to the Resmed S9 Autoset because it allows you to see a lot more data as opposed to the trend data given by the Respironics BiPAP S/T. It actually allows you to look at the data at a much higher resolution (you can see every breath taken) so I could then verify any detected apnoeas for myself.

Along with the lower pressure setting, I set the S9's EPR (Expiratory Pressure Relief) to full (3) which drops the pressure down by 3cmH2O (or 1 or 2 cmH2O, depending on your chosen setting) when it detects that you are exhaling. This is very helpful, even for psychological reasons as not only does it help you to exhale, but it provides a form of tactile feedback letting you know that the machine is "listening" to you and not trying to force a gale into your nostrils whether you like it or not.

One interesting thing that the S9's additional data allowed me to see was the moment that I stopped doing those forced breaths I that I mentioned above. This is the moment that I fell asleep. 

I fell asleep fairly quickly, and woke once when I turned onto my side and found that I needed to adjust the nasal-pillows slightly.

The following morning I checked the data and found that the central apnoeas had cleared and my AHI was a very respectable 0.4 which varied over the next few nights but still remained under 1.0.

One night I found that the S9 data showed that I'd been quietly snoring, it was also on this night that my AHI was the highest that I've had so far whilst on CPAP (0.9), although this is still a fantastically low AHI.

So the next night I crept the pressures up by 0.4 cmH2O, only to find that the snoring cleared but some central apnoeas returned, so I dropped the pressures again. It became obvious that finding a pressure that was perfect for every night was going to be a challenge.

Of course I realise that there is going to be some "natural variation" from night to night due to factors such as body position and time spent in each sleep stage but wouldn't it be good to be able to pin down what the other less obvious variables are?

My main factors are related to body position (apnoeas are more likely and frequent when I sleep supine) and REM sleep (when muscle tone is decreased in the airway), but I suspect that other factors during the day play a part.

This is where the S9 Autoset excels: In AutoSet mode it adjusts the pressure it delivers based on your need at the time, so where "Straight CPAP" is limited because it can only give me one pressure throughout the night meaning that 8cmH20 may be too much for me at some parts of the night (causing Central Apnoeas), yet not adequate for other parts of the night) where 10 or 11 cmH2O is more appropriate.

I set my S9 to "Autoset" mode and adjusted the settings so that the machine would work within fairly restrictive limits just to get me comfortable with the idea. In the morning I could see from the ResScan software that the machine had delivered the maximum permitted pressure at some points in the night, so I gradually extended the pressure range over a few nights until the machine didn't reach my ceiling limit and was able to deliver the necessary pressures.

The following graph of the pressure that the S9 delivered over one of the later nights illustrates how my requirement varies through the night. 

On the night above I woke myself up snoring after several hours (just before the red vertical line), so I raised the lower limit and went back to sleep, this is why the graph above shows the delivery of pressure that is lower than permitted minimum pressure at the start of the night.

Had I been prescribed straight CPAP based on the pressures titrated on this night then I would have had to have a constant pressure of between 10 and 11 cmH2O to eliminate all my obstructive apnoeas. However, the chances are that I would have then had more central apnoeas occurring. A compromise pressure of 9 cmH2O would have removed the majority of apnoeas but would have been inadequate when my obstructions were at their most severe. There could also have been central apnoeas occuring at this pressure for some of the night.

The textbook, "Sleep Medicine Pearls" by Richard Berry MD describes this well with a case study of a patient unable to tolerate the high pressures needed to treat his obstructive apnoea. If you have access to the book you can find the details under Patient #43. In fact the whole book is packed with case studies that provide a unique insight into treating sleep issues.

If high pressures can't be tolerated it may be preferable to have a lower than optimal pressure setting just to ensure that some benefit is obtained, although it is likely that these patients would benefit more from Bi-Level PAP which allows a much lower expiratory pressure.

In Autoset mode, the S9 allows low pressures but can deliver the higher pressures when necessary, giving you the flexibility (and comfort) of both in one setting. 

Some good news: my nose isn't as big as I thought...

I found that I woke up several times in the night and had to adjust the nasal pillows but each pack of Swift FX nasal pillows come with three sizes of pillows. I found that when I decreased the size of the nasal pillows to the medium size (although the large were comfortable and the leak minimal) the medium pillows were more comfortable and needed a lot less adjusting when I first put them on and hardly any throughout the night.  

I slept really well and took a look at the display screen on the S9 when I woke.

I was greeted by an AHI of 0.0 and a green smiling face telling me that the nasal pillows were a good fit and weren't excessively leaking.

The ResScan software also confirmed the Zero AHI. 

Now that I use the Autoset mode, my AHI is always under 1.0 regardless of what position I sleep in or even if I've had a glass of wine.

It actually feels good to sleep on my back again, I'd been using the Rematee side-sleeping belt for a while and found that I missed sleeping on my back. With CPAP I didn't ache when I woke up. CPAP was surprisingly unrestrictive and I soon learned a manoeuvre to clutch the hose and move it with me if I wanted to turn in the night.

To be fair I could have just let the S9 go on full unrestricted auto from day one and it would have delivered the same pressures, but from mine and my son's previous experience with Non-invasive Ventilation, a large factor in whether it is successful is down to whether the sleeper (patient) feels comfortable with it, yes the numbers are important (after all that is the whole point of the therapy), but the patient experience is also key as that alone will probably be the biggest factor in whether they are "compliant" with it (ie use it for 4 hours or more a night), after all many PAP machines don't allow the user to see their AHI data so they can only judge based on how it feels.  

Another part of the experience is the mask that is used. There is a wide choice of masks available, and it's important to find one that is right. Also humidification can help people feel more comfortable with PAP therapy, this is something else that should be available to them along with all manner of accesories such as hose holders - really anything that will prevent someone giving up. That said, CPAP therapy isn't right for everyone as my son's situation shows, so good communication with a committed Sleep Consultant is vital in order that the right treatment be offered. 

I think looking into things in this detail was necessary for me, although it was a rather involved way of getting used to CPAP and trusting it, it has been well worth it. I feel a lot more awake in the mornings (generally only sleeping for 7.5 hours now) and my AHI has been consistency the lowest it has been in probably 20 years.

I think the graph below speaks for itself.

CPAP is a clear winner and one that is likely going to be impossible to beat but that's not going to stop me trying out other apnoea remedies to see if they can come close.

CPAP has also made a huge difference to my snoring, the results of which I'll post in a few days. 

For the future: 

• I'd like to see if the pressure requirement decreases if I take a dose of 5-HTP at bedtime.
• Although I don't intend to change my nasal pillows, I would like to see what difference other masks make to the experience.

Useful Links

Michael F. Fitzpatrick, Christi E. D. Alloway, Tracy M. Wakeford, Alistair W. MacLean, Peter W. Munt and Andrew G. Day
Can Patients with Obstructive Sleep Apnea Titrate Their Own Continuous Positive Airway Pressure? 
(full text PDF available to non-subscribers via the link)

Gao W, Jin Y, Wang Y, Sun M, Chen B, Zhou N, Deng Y. 
Is automatic CPAP titration as effective as manual CPAP titration in OSAHS patients? A meta-analysis.

Mandibular Advancement Devices: #1 Snoremate

If you've never seen one of these devices before, imagine it as a two gumshields stuck together, with the gumshield for the lower teeth fixed so that it forces the wearer to jut their jaw forward. The mandible is the jawbone, hence the term "Mandibular Advancement"

The idea behind this is that forcing the jaw forward creates more room in the airways by shifting muscles and fat forward slightly, reducing the likliehood and severity of airway obstruction.

Mandibular advancement (either by a specially made dental device, or by surgery) is a tried and tested concept of reducing snoring and sleep apnoea, so I'm not really putting that to the test, but rather I'm trying out the off the shelf concept, although my snoring is sleep-apnoea related, so unless the device can remedy the apnoea, I doubt that it will affect my snoring. 

SnoreMate

This is an off-the-shelf (but custom fit) mandibular advancement device (MAD).

The SnoreMate is made from a thermoplastic that you dip in hot water to make it soft, then bite into it to form a custom fit for your teeth. The SnoreMate can be adjusted by re-dipping it in hot water if you feel the need to advance your lower jaw more to increase the effectiveness of the mouthpiece, something that I did after a few nights of using it.

It was easy to mould, and is the most comfortable of the two mouthpieces that I've tried so far (the other device being the SomnoFit) which I found was too bulky to be comfortable for me). I was surprised that on the first night It stayed in place until around 2am, and on subsequent nights (to get used to it before I monitored it) it remained in place until the morning. It was actually quite easy to get used to. In fact it was surprisingly comfortable, so I purchased a second Snoremate and moulded that one slightly further forward rather than risk losing the comfortable positioning of the first one.

However, there are a couple of drawbacks to the mouthpiece, the main one is saliva build-up! I found myself waking at night just to swallow and clear my mouth. The other drawback is that my gums and a couple of teeth ached for a few of hours in the morning.

As far as snoring reduction went, using the method explained in this post, I was very surprised. I imagined that everything I used in addition to the Rematee would either improve on the Rematee's effect or make no change. I think that the graph shows why I was surprised...

The SnoreMate actually made my snoring louder! This would have been very annoying for anyone in the house as I managed to reach 98db (about the volume of a drill drilling!). This is an unacceptable volume when you consider that I was already sleeping on my side and wearing a mandibular advancement device. Although to be fair, it is an anti snoring device, and my snoring is more than snoring, it's related to sleep apnoea.

In the following clip it resembled a moose-call.

However, I had a lower AHI for the three nights (mean 2.05) with one of the nights using Snoremate with the Rematee giving me my lowest ever AHI of 0.77.

If I had to speculate as to why the snoring increased in volume (and sounded slightly different in tone) yet the AHI was lower, I'd have to say that it was probably due to the fact that, by design, it is impossible to breathe through your mouth with the SnoreMate, so the air has a to take a different path through the nasal passages, rather than through the open mouth of the snorer.

Even wilder speculation:  The SnoreMate was probably doing what it was intended to and tightening / stretching the muscles in the airways meaning that they were less prone to relaxing, hence less hypopneas. Again, further speculation, but it is possible that this also caused the snoring to be louder in the same way that in deflating a balloon a screech caused by keeping the neck taut is louder and higher pitched that if you were to let the neck relax causing a quieter lower-tone rapserry sound.

I was so intrigued by this hint that it was working, that I've made an appointment at my dentist to have a professional Mandibular Advancement Device constructed for me and I'm looking forward to being able to compare the results. My hope is that the professional device will allow me to further advance my jaw, keeping my airway muscles even tighter, elimating my apnoeas and maybe my hypopneas (and hopefully snoring too).

Snoring Remedies? Results for 5-HTP

Using the method detailed in this post I decided to see if 5-HTP had any effect on my snoring.

I was keen to try out 200mg of 5-HTP first, given that it had previously had such a positive effect on my AHI.

My thinking was that if 5-HTP had been able to reduce the gross movements of my airways that are responsible for obstructive sleep apnoea, then maybe it would also be able to reduce the smaller movements that are responsible for snoring. However, I suspected that as it hadn't been able to completely prevent airway restrictions that it wouldn't have an effect on the smaller movements. 

It seems that I was wrong. The results were promising to say the least. 

5-HTP was able to reduce my snoring further than that offered by just sleeping on my side.

Given that from my data alone there are two indications that 5-HTP is beneficial to sleep (AHI reduction and a reduction in snoring) I would love to see a larger scale experiment or trial take place, after all I am just "n=1".

Prior to taking 5-HTP I researched it in medical literature with regards to dosage and possible side-effects. After seeing my results I went back to the literature and started looking for a possible mechanism or explanation as to why 5-HTP might have this effect.

I'm working on a summary of what I've found and will post it in the near future.

For the future:

• I'm curious as to whether the 5-HTP would reduce my supine snoring index, given that my snoring is at its loudest and most frequent when on my back so I will record a three-night mean of 5-HTP sleep when I will be free to move and produce supine and free-to-move snoring indexes via the Visi-Download software.
• I'm also curious to see what different doses would achieve, so I'll carry out three night mean trials of side-sleep + 50mg, 100mg and 300mg of 5-HTP and measure the effect on my AHI, snoring profile and sleep stage data.

Snoring Remedies? Introduction and Positional Therapy Results

Snoring occurs when the tissues of the airways relax during sleep causing the air to vibrate as it passes over them, in a similar way that deflating a balloon causes the balloon's neck to vibrate and make that familiar raspberry sound.

This can be illustrated by the following airflow waveform taken from my snoring using Stowood's Black Shadow Sleep Monitor.

What should have been nice smooth breaths like these... 

...ended up becoming jagged saw-toothed breaths like these...

...resulting in a rasping snore.

To give you an idea of what the Visi-Download software allows me to see (and how the vibrations above actually sound) I've made a short video of a few snores that I recorded on one of my baseline nights:

Snoring can simply be just that - a noise, it can be a nuisance if it's too loud as it can wake others in the house, if it's loud enough it can actually wake the sleeper! However, it can also be much more than just a noise. Besides being the cause of much nocturnal anger and maybe even the cause of a relationship breakdown, it can also be a sign of a greater health issue such as sleep apnoea.

I snore. In fact my snoring is sometimes so loud that I hear it in my dreams.

If only that were as as serious as it got, but my snoring is actually due to sleep apnoea. As documented in many posts on this blog, I have mild sleep apnoea.

I've found some ways to bring the apnoea to acceptable levels with a typical AHI of between 1 and 3, (an AHI of under 5 is considered normal if it doesn't cause symptoms such as daytime tiredness etc). The way that I did this was to keep off my back when I slept by using a Rematee belt. This also had a knock-on effect of reducing my snoring, but not eliminating it.

On the nights that I've recorded while using the Rematee to keep me off my back, my AHI has been stable and my snoring has reduced (the residual respiratory events are mainly hypopneas, although the lowest that my oxygen saturations drop to has improved, it still drops to around 79%).

Besides looking for other ways to bring my AHI down even more, I want to go further and eliminate my snoring. I guess that my long term quest is to see if it's possible to have the much hyped perfect night's sleep.

Many snoring remedies (and there are many) say that they are not suitable for snoring that is caused by sleep apnoea, so with my new found side-sleeping "normal" AHI and some residual snoring I now find myself in a good position to put them to the test.

Quantifying Snoring 

The problem is that snoring is hard to quantify. Yes, you could ask a partner, but that answer would be fairly subjective. You could judge by how you felt in the morning, but again that is subjective. You could even place a Dictaphone beside the bed to record your snoring but besides but again, how do you score the recording?

One of the channels that Stowood's Black Shadow sleep monitor measures is snoring, and it does this via a calibrated microphone, allowing you to quantify how loud each snore actually is. It also derives a second channel from the sound to identify individual snores, thereby allowing you to actually have a snore-count. From there it calculates a snore-index (a number of snores per hour, grouped according to volume).

So, my method is this:

By keeping off my back I am essentially apnoea-free, leaving only the snoring to be addressed, so to ensure this and to eliminate the effects of a variable sleep position on my snoring (and to bring my AHI to normal), I'll be wearing the Rematee belt whilst putting a different snoring remedy to the test each night hoping to eliminate my remaining snoring.

I'll record sleep data for three nights per selected remedy and calculate the mean snoring profile for each by graphing each remedy according to:

• Hourly snores between 55db and 65db
• Hourly snores between 65db and 75db
• Hourly snores greater than 75db 

This "Snore Profile" will not only allow me to see if the total snores have been reduced, but it will allow me to see if the remaining snores are quieter.

This graph shows the mean snore profile for my Supine Baseline, Free-to-Move Baseline (calculated from the same nights), and my Rematee baseline. 

The majority of my snores are louder than 75db regardless of whether I sleep on my side, back or am free to move around! Not unexpectedly then, it follows that the next largest chunk of my snoring falls between 65 and 75 db with hardly any under 65db.

The "Remedies"

There are plenty of "remedies" available. Some of these are traditional remedies (using the term loosely), and some are more modern commercially available remedies.

• Positional Therapy - (Tennis Ball / Rematee) already shown above

It's clear to see the positive effect that side-sleeping has on reducing my snoring. It reduces my snoring by over 50%, so it is likely that this in itself will be a clear leader in the remedy league table. I suspect that for many snorers (where their snoring is not caused by apnoea) that the Rematee and side-sleeping could eliminate snoring completely.

• Mandibular Advancement Devices
• Nasal dilation
• Snore Spray
• Humidifier by the bedside
• Anti-Snore Ring (Acupressure)
• Anti Snore strip (on roof of mouth)
• Drinking a glass of water before bed
• A night time garlic gargle
• Toothpaste under the nose
• Electric snore-shocker devices
• Nasal irrigation

 I also want to explore the following to see if they have an effect on my snoring.

• 5-HTP
• Melatonin
• L-Tryptophan
• Blood sugar levels
• Large dose of vitamin B6

I'll pick from this list (avoiding some completely) and put them to the test for three nights to get a mean snoring value. To avoid creating a very long post I intend to create a separate post introducing each remedy (and how well it performed). When I've finished I'll then chart the results together. 

Besides bringing my AHI to an acceptable level to address the residual snoring, part of the reason for staying on my side for the entire night is that it will allow a fair comparison of snoring in all sleep stages (I typically spend around 2h10 minutes in REM and 45 minutes in Slow Wave Sleep). I'll also be keeping an eye on my Zeo stats to see if any of the methods have an effect on my sleep composition. I expect that the methods that rely on disturbing you during snoring episodes may have a negative effect on REM or Slow Wave Sleep.

Update on Saturday, May 19, 2012 at 1:08PM by Hypnagogia Blog

5-HTP Results

Using the method detailed in this post I decided to see if 5-HTP had any effect on my snoring.

I was keen to try out 200mg of 5-HTP first, given that it had previously had such a positive effect on my AHI.

My thinking was that if 5-HTP had been able to reduce the gross movements of my airways that are responsible for obstructive sleep apnoea, then maybe it would also be able to reduce the smaller movements that are responsible for snoring. However, I suspected that as it hadn't been able to completely prevent airway restrictions that it wouldn't have an effect on the smaller movements. 

It seems that I was wrong. The results were promising to say the least. 

5-HTP was able to reduce my snoring further than that offered by just sleeping on my side.

Given that from my data alone there are two indications that 5-HTP is beneficial to sleep (AHI reduction and a reduction in snoring) I would love to see a larger scale experiment or trial take place, after all I am just "n=1".

Prior to taking 5-HTP I researched it in medical literature with regards to dosage and possible side-effects. After seeing my results I went back to the literature and started looking for a possible mechanism or explanation as to why 5-HTP might have this effect.

I'm working on a summary of what I've found and will post it in the near future.

For the future:

• I'm curious as to whether the 5-HTP would reduce my supine snoring index, given that my snoring is at its loudest and most frequent when on my back so I will record a three-night mean of 5-HTP sleep when I will be free to move and produce supine and free-to-move snoring indexes via the Visi-Download software.
• I'm also curious to see what different doses would achieve, so I'll carry out three night mean trials of side-sleep + 50mg, 100mg and 300mg of 5-HTP and measure the effect on my AHI, snoring profile and sleep stage data.

Lucid Dreaming - Sending a Signal to the Waking World

Lucid Dreaming seems to be a bridge between the waking and dream worlds. You are dreaming, yet you are conscious of dreaming and capable of having rational thoughts during a jumbled dream.

Being lucid doesn't mean that you have full control over your dreams, despite being aware that I'm dreaming I still find that I am compelled to "play along" with the dream that I'm given. So, for example, if I find myself dreaming of a street scene, I can't magically transform it into countryside. In order to change the scenery I have to make the change fit into the story somehow, even if the scene-change is something as crude opening a shop door and "knowing" that it takes me to the countryside.

All this is wrapped in the fact that (for me at least) lucid dreaming is a constant struggle to remain lucid, it doesn't take much to lose lucidity and slip back into a normal dream. 

So when I suggested sending a signal from a dream in this blog-post, I thought it unlikely that I'd ever be able to remain lucid and have the presence of mind to consciously send a signal to the Zeo Raw Data (via ZeoScope) marking the lucid dream.

I'd been briefly practicing what sort of a signal to use before going to sleep every night, hoping that it'd stick inside my head if I was fortunate enough to have a lucid dream. Given that the signal has to be based on eye movements I was fairly limited in what I could do, but the practice sessions showed me that flicking my eyes from side to side just seemed to produce a very noisy signal and something that could be interpreted as EMG noise from my forehead, so I settled on eye movements to the right, then centre, which produced a nice peak on the raw EEG data (it is this type of peak that the Zeo filters to use for its EOG signal).

Because the eye movements were forced as far right as I could manage the amplitude of them rose above the normal eye movements of waking and REM. 

(Normal eye movements during a period of REM (right to centre first, followed by left to centre)

On Wednesday night I became lucid in a dream and managed to stop and send a signal using my eyes that was picked up by the Zeo.

The first thing that I remember about the dream was that I was late to get to a party and I still had to stop off and buy a bottle of something to take along. I lifted up and flew along the coast of the Thames Estuary not far from where I live. 

This was the thing that prompted me to become lucid. Flying is such a break from the everyday laws of physics that it jolted me into realising that I was dreaming.

So, I went along with the dream, flying to the party but stopping off at a small stone-clad Welsh off-licence (I have no idea why I ended up in Wales). As I landed and my feet touched the ground I remembered that I was wearing the Zeo headband and recording the raw data, so I darted my eyes sharply to the right and centred them again.

Then I thought, "That's just one, maybe it'll get lost in the other data", so I repeated it 5 more times, then bought my wine and Jaffa Cakes, lifted into the sky and headed for mainland Europe (where the party was apparently).

Shortly after arriving at the party (which turned out to be in a 1970s church hall), I woke up and glanced at the clock before falling asleep again.

In the morning I found it easy to see the signal that I'd recorded. The peaks were a lot larger than my typical eye movements. The first peak is my initial signal, then after a pause I gave 5 more right-eye movements.

So, not as significant as a signal picked up by SETI but still, this is a signal from the dream-world to the waking world. It actually reassures me because several people have asked me, "How do you know that you're not just dreaming that you know you're dreaming?" implying that lucid dreaming is itself a dream. This shows that it isn't. At the time of the signals, I remembered that I was actually asleep in bed and not outside an off-licence in Wales and although I was still standing on the cobbled street and not able to sense the waking world I was able to make an impact on it via this signal.

From the Zeo raw data it seems that a broken night played a part in triggering this dream, and I suspect that respiratory arousals were the cause again as I wasn't wearing the Rematee belt. A rough breakdown of the time surrounding lucidity is as follows...

• 04:34:45 Woke from a long stable period of N1/N2 (light) sleep
• 04:39:15 Entered REM (from wake)

Repeated awakenings and a mixture of N1/N2 and REM until... 

• 05:00:15 Entered stable REM
• 05:03:26 Began to signal lucidity
• 05:03:37 Gave last eye movement of lucidity
• 05:06:14 Woke and looked at the clock before going back into REM again
• 05:11:14 REM ended

So this places my lucid dream within REM, which was the subject of speculation for years until Stephen LaBerge confirmed that lucid dreams are actually REM dreams. 

Jeff Warren also has a good explanation of the technique in this exerpt from his book, "The Head Trip". 

Stephen LaBerge, William Dement, Lynn Nagel and Vincent Zarcone took things a lot further and even recorded morse code signals from a lucid dream via muscle-movements.

I'm still not any closer to seeing a trademark brainwave pattern of lucid dreaming, but I suspect that this is due to the single site EEG. 

I'd like to practice this further and if I'm fortunate enough to be able to do this again I'd like to try to repeat the signal every 60 seconds (as it appears to me in the dream), or at key points in the dream (such as taking off and landing, meeting a person etc etc) it would be interesting to see if these signals can be used as markers to chart the flow of time through a dream.