Urban Jungle

PUBLISHED : Friday, 15 February, 2008, 12:00am
UPDATED : Friday, 15 February, 2008, 12:00am

This week: Difficult diagnosis

Was that really a seizure or are you just happy to see me? A regular client of mine came running into my consultation room the other day with her little terrier crying: 'My dog just had a seizure. It yelped and then urinated uncontrollably and fell over. Is he going to die?' All the while her little terrier, named Jelly, was staring rather quizzically at me. He was probably wandering what all the fuss was about. She was so sure it was a seizure it was almost convincing. But I doubted her story.

Clients and their ill pets' symptoms are always out to trick me. I need to be on full alert when dealing with them. And seizures can be a very tricky symptom.

I didn't go out and insult the woman by saying she was wrong. I said: 'I think there is more going on than meets the eye.' A superficial examination failed to reveal anything obvious, so I asked the owner what Jelly was doing before the 'seizure'.

She answered: 'Nothing much. I just got home from work and she was happy to see me and while she was jumping up and down and barking, she just started seizuring.' I made a note that the dog would have a 'seizure' when excited. I listened carefully to the heart and lungs and noted nothing audibly abnormal. I went as far as to conduct an electrocardiogram, more commonly known as an ECG, on Jelly to see if there were any electrical conduction problems with the heart but again, there were no signs of anything out of the ordinary.

I further asked in detail about the actual seizure and Jelly's owner said: 'One moment she was bouncy and the next she just yelped and fell over. Her body was soft to the touch and there wasn't any struggling. It lasted a few seconds and then she was up again but was a little tired looking.' I noted from this that there was no involuntary muscle movement commonly associated with a seizure. It really didn't sound like a seizure to me. At this stage in the old days I would have asked the client if she could capture the seizure on film to help me differentiate between a seizure or something else, but nowadays I have a new trick up my sleeve.

Most tech-savvy people in Hong Kong would know about Bluetooth. It's a technology that allows wireless communication between two machines. What has that got to do with veterinary medicine? Some clever sod has invented a Bluetooth-enabled ECG. With the old-fashioned ECG, the dog had to be attached via various wires to the machine and that meant I could do an ECG only in the confines of a table. With the Bluetooth version I can have the dog running around the client with the ECG strapped safely on its back and allow me to monitor an exercising dog's electrocardiogram. This can reveal much about the heart's conductivity.

We kept Jelly in the clinic for most of the day but the ECG didn't reveal anything useful. I was beginning to think I was barking up the wrong tree.

But I have another technological trick up my sleeve. What if I could get an ECG of Jelly during a seizure? Surely that would give me all the clues I needed. It would be rather unethical to induce Jelly to have a 'seizure' in the clinic. So I had to send Jelly home and have it happen naturally.

Unfortunately, the Bluetooth range is only 20 metres and could not reach from Happy Valley to Tuen Mun, where the client lived. Fortunately, the ECG also has an SD card slot. For those less tech-savvy, an SD card is an electronic storage device much like a floppy disk, only smaller. The ECG is able to store a whole day's data on an SD card for later analysis.

So we sent Jelly home with the ECG attached and got the owner to return the results the next day. Fortunately, for us and unfortunately for Jelly, he had a seizure that night, probably because of the extra excitement of the visit to the clinic. And lo and behold my hunch was right - the seizure was really an episode of syncope, the medical term for fainting.

To put it simply, there was a blockage in electrical conduction in Jelly's heart that was made worse when he was excited. The heart has an upper storage chamber, called an atrium, where blood returning from circulation is stored. When this storage chamber is stimulated by an electrical current, it contracts and squeezes its contents into the lower chamber, called the ventricle. The muscle of the ventricle is much larger and when it contracts, it is able to force the blood out of the ventricle and around the whole body. The same electrical current that stimulates the atrium travels down conduction fibres and stimulates the ventricle. But in Jelly there was a blockage in those conduction fibres, hence Jelly's brain did not get enough oxygen during stress and Jelly would faint.

Luckily for Jelly there are drugs that help and since the successful diagnosis, Jelly hasn't fainted once.