Sunday, July 17, 2011
Some info about the testing - physio
Physiotherapy and Pulmonary Rehabilitation are very important to anyone with a chronic lung disease. It's essential to keep active and to learn how to focus on strengthening the correct muscles that are important for breathing, and the large muscles that use the most oxygen.
I've been attending pulmonary rehabilitation sessions since 2004. When I started I was still quite fit and active. I was still working full time and also travelling for work. The only time that I ever really encountered a problem was when the colleagues that I travelled with walked too fast for me at the airport!
As the years have progressed, things have become worse. At first, I just started using oxygen at my pulmonary rehab sessions on 2L/min. Then I got to the point where I needed oxygen for walking / shopping etc. outside of the house. Now I'm at the point where I need oxygen 24/7 on 2L/min and then I have to increase it to 4L/min for walking/exercising etc.
The way that the physiotherapists measure a patients exercise tolerance is with a 6 minute walk test. (6MWT). They set up a straight path of at least 25 metres, and the patients needs to walk back and forth from end to end as fast as they can for 6 minutes. You can only stop if you get too dizzy from lack of oxygen to the brain.
Predictive equation for females: 6MWD(m) = 525 – (2.86 age, yrs) + (2.71 height, cm) – (6.22 BMI).
For me the predicted outcome should be = 525 - (2.86*37) + (2.71*170) - (6.22*23.5) = 733.71 metres
On 4L/min, I actually achieved 325 metres with my SpO2 in the low 70's (should be 100%).
I'd love to know what the results were from my very first 6MWT in 2004. I really should ask my physio if she can dig out the records and check!
Which has got me to thinking.... I used to be a long distance runner when I was at primary and high school. Even in Year 12, I came 2nd in the school cross country. I could easily run 3 kilometres in 15 minutes.
325 metres - 6 minutes = 3.25 kms/hr
3000 metres - 15 minutes = 12 kms/hr
If you look at the top right of the photo - it has a results for ABG's which means Arterial Blood Gas. It's where they stick a really skinny needle directly into the artery in your wrist (and yes it's as gross as it sounds) to take a blood sample.
The normal range for PaCO2 is 35-45mm Hg - mine is 57
The normal range for HCO3 is 22-26mEq/L - mine is 33
This means that I have compensated respiratory acidosis or too much carbon dioxide in the blood.
I'd better watch out then, I might get slapped with a carbon tax!