Wednesday, March 31, 2010

From Vent to Diaphragmatic Pacing System -- Part 1

I, Bill Miller, am paralyzed from the neck down and ventilator dependent due to a high-level spinal cord injury (SCI) that I incurred in August of 1997.  Though I learned of Synapse Biomedical's NeuRx Diaphragm Pacing System (DPS) several years ago, I didn't feel like it could do much to improve my quality of life.  I actually thought it would decrease my quality of life, primarily because the DPS doesn't allow the user to initiate breaths.  Why is that important?

My voice is my primary tool to the world, so the better my speech, the better my quality of life.  Using a Passy-Muir (Speaking) Valve (PMV), I have nearly continuous speech while receiving 13 breaths per minute (BPM) at a volume of 900 cc (just less than half of a two liter soda bottle).  However, sometimes I do "run out" of air to speak with, before I finish my thought.  Fortunately, there are a couple of ventilator settings that enable me to initiate another breath, with just a slight "shrug" of my shoulders (I use my neck muscles to pull my chin down and chest up a little; that’s also how I can breathe when disconnected from the ventilator).

Initiating a breath enables me to shorten the pause in between "scheduled" breaths and continue speaking.  The DPS doesn't allow users to initiate breaths, hence my initial thought that it would decrease my speaking ability and thus my quality of life.  But there's a simple fix: just increase the breath rate.

I'm told that my volume when stimulated to breathe by the DPS should be around 800 cc, so with 14 or maybe 15 BPM, my guess is I won't need to initiate any breaths.  That's what I suspect I'll want during the day when I'm speaking, and I can decrease the BPM for sleeping.

I was also leery about only having battery power for the DPS.  It's comforting to know I have unlimited vent time when plugged-in to a standard outlet, but to also know I have batteries for my vent that give me roughly 12-14 hours on a full charge, and charge simply by being plugged-in.  But I have a friend who has used the DPS essentially 24/7 for over five years, and he hasn't had any issues with the batteries.

With those issues "solved" in my mind, I began to think how I could benefit from the DPS. 

* * * * *

I've heard DPS users' senses of smell and taste both improve, though I cannot imagine certain foods tasting any better than they do now (I enjoy eating:).  And I can smell fairly well when I actively try to take air in through my nose (and selective smelling can be a good thing!:).  So those are minimal benefits for me personally, but here are several that are not.

The biggest benefit I hope to gain from the DPS is being comfortable enough with it to remove the ventilator and vent tray from my wheelchair.  Actually, I'm in need of a new chair (this is my original chair, which is over 12 years old) and I would like to get a chair that can stand me up, so that I can both view the world from my natural height, and bear my weight much more frequently than I do now.  Bearing weight is highly beneficial for one's bones and entire body, I'm told.  Plus, I do speaking engagements, and plan to teach at the community college level upon completing my master's degree -- and how cool would it be for a quadriplegic to be able to stand up when speaking?

Not having a ventilator on my chair would also enable me to maneuver in tight spaces more easily.  And I could drive my wheelchair while standing -- I'd love to roll upright across the stage when I graduate (I rolled seated across the stage for my bachelor's degree, which can be seen on my website HERE).

The DPS would definitely improve my speech quality in bed, because it would be like using a speaking valve all the time.  (The PMV is a fantastic little one-way valve that enables one to take in air easily through one's trach, but seals off in the exhale direction, thus enabling the user to have air around his/her vocal cords even when the vent isn't giving a breath, which allows for more continuous speech.)  I don't currently use a speaking valve in bed because the valve tends to dry out my airway, so in bed, I re-humidify my airway.

Another benefit would be that the DPS should allow me to either cap my trach or use a small speaking valve, either of which would make getting dressed a bit easier, and also would make wearing certain clothes MUCH easier.  Right now, with the vent circuit attached to my trach, it protrudes about 1.5 to 2 inches, which makes wearing some dress shirts or a tie quite difficult.

I could also potentially wear a turtleneck or mock-turtleneck, which I cannot currently do (because they put pressure on my trach and stoma), and they could hide my trach altogether.  I'm not self-conscious about my trach or general appearance, but that would obscure a sign of my disability, which would be good because I try to not let my disability define what I can do -- despite being paralyzed from my neck down, I still feel like I have the ability to accomplish quite a bit (I thank the Good Lord for blessing me with good support systems).

Some DPS users have even had their trachs removed entirely.  Even if I'm able to build up to 24/7 DPS use, it would take me a while to even consider having my trach removed.  That's a big step -- that maybe I'll get to consider in six months or a year.  That said, my on-vent quality of life is high (many thanks to a CoughAssist machine, which you can read about on my website HERE) so I won't be too disappointed if I'm not able to use the DPS.  No worries!

This is the first of (hopefully) five entries I've been asked to submit for the International Ventilator User's Network (IVUN).  If all goes well with my efforts to become a DPS user, then here are the proposed entries: Column 1 (April 2010) Why I'm seeking a DPS; Column 2 (June 2010) Candidate screening / pre-surgery requirements; Column 3 (August 2010) DPS surgery; Column 4 (October 2010) Post surgery use; Column 5 (in 2011) Extended use.  IVUN's website is

A PDF file of IVUN's newsletter is below; I'm on page 5 with a nicely edited version of what I wrote above:

Bill Miller :-)
C1-2 Quadriplegic with a 221 High Bowling Game
Co-founder of Manufacturing Genuine Thrills Inc. d/b/a MGT
My blog:
Business website:
Personal website:

1 comment:

Leslie Lim said...
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