SJA - John C. Kirk
Jul. 26th, 2006
02:08 pm - SJA
Summer time is something of a peak for St John Ambulance, with loads of duties going on.
On Saturday I was off to a fundraising fete. When we arrived, it was baking hot, and we were worried that everyone would get sunburnt/dehydrated, so we put out a couple of announcements nagging people to drink water and stay in the shade. A bit later, the wind picked up - more specifically, it picked up the gazebos in the car park and sent them flying around, so we lent a hand in dashing after them and tying them down/packing them away. On our ambulance, we have some metal circles in the floor that are specifically designed to clamp the trolleybed into - they can also be used to secure a wheelchair with straps. It does occur to me that it might be useful to have a standard shape for these, and then inset them in a car park, so that you can put up things like gazebos when necessary, and ignore them the rest of the time. Anyway, after the wind came the rain, to the extent that everyone moved inside, and the event finished early. Bit of an odd duty, that one...
Last night was our regular training session, and this one was all about blood pressure. It was very interesting, and one of the best sessions I've been to in ages, so I now understand a bit more about what the figures mean (e.g. why you can't just do division when someone says "X over Y"), and I had a bit of practice with the equipment. I'm fine with the completely automated cuff, but I'm not quite so good with the manual version - the cuff itself is fine, but I have trouble checking the pulse. As I understand it, there are two approaches to this:
a) Pump it up to to 200, then bring it down from there.
b) Pump it up gradually, while checking the pulse at the wrist, and see when the pulse disappears. Then add 20, and use that as the upper limit for the next check. In my case, that's about 130, so it's a bit more comfortable if I don't get my arm crushed unnecessarily.
I've never been very good at this, but generally it's not necessary in first aid, so I can get away with it, e.g. if you're doing CPR then you look for "signs of life" rather than specifically feeling for a pulse. Anyway, I was eventually able to find a pulse in various wrists, although I couldn't feel that at the same time as pumping the cuff - I think that's to do with my inability to focus on two things at once, rather than the increased pressure actually interrupting the pulse. I can probably get the hang of that, so I just need to practice a bit more, if I can persuade friends to lend me their wrists...
The more tricky part was using the stethoscope to listen to the pulse near the elbow. When I first put the stethoscope on, my initial reaction was "Wow, this thing really works - it makes noises louder!" Admittedly that's a bit of a stupid thing to say, but I think the last time I used one was the plastic thing that came with my toy doctor kit when I was 5 years old, and the metal version is certainly more effective. The idea is that you hear the pulse initially, then pump up the pressure to your previously determined level (e.g. 200), by which point the pulse will disappear. As you gradually decrease the pressure, the pulse will reappear, and this pressure is your first reading (systolic). As you decrease the pressure further, the pulse will disappear again, and this is your second reading (diastolic). After that, you drop the pressure down to zero, and the pulse will reappear again by the time you get there. So, this all hinges on being able to hear the pulse in the artery through the stethoscope, and I was completely unable to do this. I could sometimes hear something (with zero pressure through the cuff), but it was just a vague rustling, rather than a regular beat. Again, I think that I need to do some practice in my own time, so it probably makes sense to get myself a stethoscope - St John Supplies have a range for sale, although I'm not quite clear on the benefit you get from the £50 version rather than the £4 version, so any suggestions would be welcome.
Tonight I'm off on football duty - it's a friendly game, but I think the season restarts fairly soon. Then I'm off to an Anglo-Indian day at the weekend. Meanwhile, I'll try to do some more work on the website while I'm off work.