Hey there, hi there, ho there!
So a few weeks back I returned to London for some autonomic tests. While I was fairly prepared, there are a few things I would do differently. Even though I had been briefed by the investigations unit, I feel that some people who are due to have these tests would benefit from a few extra tips.
These are the tests that I had:
Autonomic Function Screening tests, plasma Catecholamine blood samples, head up tilt test (Autonomic Protocol), liquid meal test with autonomic responses, modified exercise test with autonomic responses to gravitational changes, cardiovascular autonomic responses to arm movements and a 24hr blood pressure monitoring using the autonomic protocol & analysis.
How do you prep for these tests?
Food and water
You have to refrain from any food four hours prior to testing and you can not drink anything until the lead up to the tests. So, I would recommend buying a breathe freshener spray as my mouth gets really stinky when I don’t drink water for awhile. So if that happens to you, you might want to bring some with you.
Luckily, my appointment was at 11am so I did have time to get up and eat something before we left. For 48 hours prior to testing you must refrain from eating anything with caffeine (coffee, tea, coca cola etc) bananas, chocolate, cocoa, citrus fruits & vanilla.
You should wear loose fitting clothes for testing as the hospital informs, they suggested shorts in the documentation but London in spring is cold! I brought a few different things to wear and knew what would work for the second day of tests. What worked best was a loose t shirt (make sure the arms are loose or short too) and leggings. They only attach the vast array of wires and monitors on your upper body. The lowest they go is your hip area.
I wasn’t sure whether I should take my meds or not and it didn’t say what to do on the documentation so I refrained from taking my Midon but took my pain killers as the mornings are the worst time for me, pain wise. Luckily, I had booked a wheelchair to travel around London in so there was no chance that if I did faint, that I’d crack my head on the pavement. If you’re unsure yourself, give your investigation team a call or send an email to ask what to do in regards to your medications. It didn’t dawn on me until that morning on whether I should’ve taken my meds or not.
If you’re travelling abroad or far from where you live, make sure that you know which train/bus etc you need to get or what route you need to take if driving. I would advise for anyone having these tests in London, to check online whether there are any delays on the tube line you’re taking. I have a tube map app that was very useful for our trips around London. Give yourself plenty of time to travel. Be sure to get to the hospital in plenty of time so you can fill out any paperwork. Because we had the two kids with us, we did get delayed a bit so I was late for my tests but what we didn’t have time to do on the first day we did on the second.
How do these tests work?
Autonomic Function screening tests
This comprises of six tests. They are performed whilst you are lying flat, which will assess cardiovascular autonomic function.
The exercises vary in length, ranging from 15 seconds for the shortest and 3 minutes for the longest. The exercises examine blood pressure and heart changes in response to various stimuli: breathing exercises, cold, problem solving and isometric exercise. There
is a rest period between each test to ensure that your blood pressure and heart rate returns to baseline before commencing the next test. The autonomic function screening test also contains an active stand test. You will be asked to stand for a maximum of 5 minutes, whilst measuring your blood pressure and heart rate.
So, the breathing exercises were very straight forward. You are asked to breathe in deeply and then breathe out slowly for 15 seconds into a small tube. Then you’re asked to breathe quickly like you are hyperventilating.
The cold test was not pleasant at all. You’re asked to place your hand on an ice pack for 1.5 minutes. It doesn’t sound very long but trust me, it feels like forever. I won’t lie, it does hurt but as soon as that 1.5 minutes is up, you take your hand off and feel instant relief.
The problem solving test was tricky for me as I have a Dyspraxia diagnosis and people with this condition tend to perform very poorly when it comes to mathematics.
You’re asked to do fairly basic maths of adding and subtracting but when we got to the big numbers, I ran into trouble. Plus the pressure of having to perform and brain fog thrown in, the odds were stacked against me but, they’re not measuring your math skills or intelligence, they want to see how your autonomic system reacts to these particular exercises.
Finally we did the isometric exercise test and this was simply having to squeeze a ball. With my weak hands and the wrists that are susceptible to dislocation, it was difficult for me but I was assured I did just fine by the lovely woman, Kiran who looked after me so well.
Plasma Catecholamine blood samples
Blood samples were taken from my arm using a small butterfly needle. Catecholamines / Metanephrines are a group of hormones (adrenaline, noradrenaline and dopamine) which circulate in the blood and help regulate blood pressure and heart rate. The levels of catecholamines/ Metanephrines in the blood changes with posture (the levels increase from lying to standing). Blood samples were taken while I was lying, following the 10 minute rest period, and while I was on the tilt table in the standing position.
On some occasions, a spot catecholamine/ Metanephrines blood sample is taken during testing. This usually occurs if the clinical autonomic scientist observes a sudden marked increase in blood pressure and / or heart rate which correlates to certain symptoms. This test is performed to determine whether there are any sudden increases in the catecholamine levels, which could explain the symptoms.
Tilt table test
A tilt table test is a non-invasive diagnostic test to determine whether your symptoms: dizziness, light headedness or loss of consciousness; are due to changes in the blood pressure and / or heart rate. At the beginning of the test, you will be asked to lie flat on a table. Two straps are put around your body to hold you in
place. After about 10 – 15 minutes of lying flat, the table is then slowly tilted to raise your body to a head-up position – simulating a change in position from lying down to standing up. The table will then remain upright for
either a maximum of 9 or 45 minutes (maximum time depends on the test requested by the doctor), while your heart rate and blood pressure are monitored continuously. This allows doctors to evaluate your body’s cardiovascular response to the change in position.
Liquid meal test
This is a procedure that’s used to examine the effects of food on blood pressure (BP), heart rate (HR) and / or symptoms.
A liquid meal is used as the effects on BP and HR can be observed after a 45 minute period. Solid foods can take a lot longer to digest (up to 7 hours). There are two options for the liquid meal:
1) complan (original flavour) + glucose + milk
2) glucose + water
Most patients will have option 1 during the test. However, I had the glucose solution as I am lactose intolerant. It is so sweet, like sickly sweet. I would love my sweet treats but this was just gross. Both meal options are suitable for vegetarians and are gluten free.
So at during this test I was asked to lie flat on the examination couch for 10 minutes to get a baseline of my BP and HR. Then I had a tilt table test. Then I had to rest again until I was asked to drink the liquid meal. Then came by favourite bit, resting for 45 minutes. It was pure bliss, no noise, no lights, nobody crawling on me or calling for me every two minutes. It was every mother’s dream. I’m pretty sure I dosed off for awhile too.
During the 45 minute rest period, my BP and HR will be monitored continuously. During the 45 minutes however, my heart rate (HR) dropped very low. My usual HR is 80-90 BPM but mine dropped to 50 for awhile. The on call doctor was called to check my stats but no intervention was needed as my HR came up by itself. After 45 minutes, I had another tilt test to see if there have been any changes to BP and / or HR following the meal.
Modified exercise test
I was asked to lie flat on an examination couch for 10 minutes or until a baseline of
my BP and HR was established. I then stood for a about 2-3 minutes. I was then again asked to rest prior to performing the exercise. For the exercise, I cycled on a bike whilst lying flat. It was tough but I needed to cycle at a continuous set speed, with the
resistance of the bike gradually increased over a set period of time. I performed the exercise as long as I could which was just 3 minutes. My knee and hips were giving out.
Following the exercise, I had yet another period of rest before standing again for 5
minutes. I couldn’t last that long either. My BP plummeted making me feel dizzy.
Cardiovascular autonomic responses to arm movements
So I basically had to hold my arms out in front of me and then above my head for a few minutes. I think I only lasted a minute. My body has become so deconditioned that it physically hurt to hold my arms out in front of me. I could feel myself getting tachycardic during the tests.
24hr blood pressure monitoring using the autonomic protocol & analysis.
I had to wear a small portable blood pressure monitor, which is on a belt and a blood pressure cuff, which was fitted to my upper left arm. The monitor will takes your blood pressure and heart rate every 20 minutes during the day and every hour during the night.
You are advised to continue with your normal activities, which will help to show your investigations team a typical profile of your blood pressure and heart rate during a 24 hour period. The monitor can be removed for a bath or shower during this period. I was also given a diary. The diary contains a list of extra activities that my team wanted me
to perform whilst wearing the monitor (these activities including measuring your blood pressure & heart rate responses to mild exercise, food and postural changes). I couldn’t do all of these activities as we were either out of the hotel, I was tending to the children or having a bath.
During the monitoring, you can eat and drink as normal prior to your appointment. Your doctor will advise you whether you need to stop any medication prior to and during testing.
After the testing, I did feel exhausted and a bit sick. Booking my wheelchair was the smartest thing I did in preparation for my trip.
A couple of weeks later Prof Mathias spoke with me on the phone (this consult does cost extra on top of the couple of thousand pounds I paid for the tests) and I received a diagnosis of Postural Orthostatic Tachycardia Syndrome, Autonomic Mediated Syncope and my Orthostatic Intolerance/Hypotension was confirmed.
If you have any questions, you can comment below or message me on my Facebook page: The Zebra Mom
So until next week,