Friday, May 29, 2015

Nicaragua - Day 12

Hello again from Nicaragua! The weather has been getting steadily hotter and so our daily trips to the pool feel less like an indulgence and more like a necessity. On days that I teach, I typically spend my morning at home with my family. We spend the time playing Uno, reading, and going to the playground. In the afternoons while I go to class, they usually go to the pool or have some other type of adventure. On hospital days, my schedule is pretty different as I'm typically out of the house by 7 a.m. It's hard to believe that we are already halfway through the program. Two weeks down and two to go.

This week in class, we did lectures on a variety of equipment such as ventilators, oxygen concentrators, electrocardiograms, and defibrillators. We also did some pretty nice labs which get the students accustomed to dealing with hands-on electrical circuits. We did one lab where students had to construct a flashlight from a battery, a switch, and an LED.
a basic flashlight!
Not all of our students are electrical engineering majors, so this can actually be very helpful. We constructed a power supply using a transformer, a full wave rectifier, and a capacitor. We also got to blow a fuse with a battery, just to see what what happened. The students are asking lots of really good questions, and as always I'm probably learning more than they are in the process.

Yesterday I took 12 students back to the hospital in Nandaime. This is a small hospital in a village which doesn't have an engineering staff. This means that when things get broken or fall out of calibration, there is really no one to help them. Therefore, they had a huge inventory of things for us to look at. These ranged from the somewhat mundane, like a floor lamp, to tediously complicated, like an autoclave.
the control panel on the autoclave is simply a metal rod with some screws in it that open and close a series of switches when it is turned.
We successfully recalibrated about eight standard scales, and also repainted them because they were pretty grungy. We fixed 3 or 4 blood pressure cuffs which weren't working for various reasons. A couple just had some minor tubing problems that weren't too hard to fix. We were given a nebulizer which basically worked OK, except it was chock full of dust, which was taxing the motor. We clean it thoroughly, and returned it to the floor. We re-tackled the two autoclaves that we started working on last week. We took them all apart and washed out all of the copper tubing with vinegar, hoping to dissolve any mineral deposits inside. Even though these things are frighteningly complicated, we succeeded in putting them back together properly, which was a victory in and of itself! One of them appears to have been completely fixed! We still need to do a little testing, but it successfully pumped water into the chamber, heated it up, and then pumped it out afterwards. The biggest problem seems to have been that someone mis-wired the power supply switch. The other autoclave still doesn't work quite right, but it gets much further in its cycle than it used to, so I guess that its own little victory for now. Hopefully we will get another crack at both of those next week.

In one of the more bizarre things that I have ever seen, one of our students was taking apart a microscope that wouldn't turn on. She discovered that a lizard had crawled into the microscope and shorted out the power supply. The fuse had successfully blown to protect the electronics, but the lizard didn't fare so well and was found petrified on the circuit board!
a petrified lizard!
As if that wasn't enough, we found a clutch of lizard eggs in the microscope, and then we accidentally discovered that one of those eggs still contained a live baby.
a clutch of lizard eggs found deep inside the microscope
Unfortunately, we accidentally cracked that egg open, so the baby was born right in front of us, albeit somewhat prematurely. If you aren't squeamish, be sure to check out the video. Anyways, that was a first for me. Good luck seeing that in the university classroom!

In a more humbling moment, we were handed a handheld ultrasonic fetal heartbeat monitor. The doctor told us that it worked but gave noisy measurements and that the measured heart rates were definitely off. She told us to be careful since it was their only working one. The problem seemed pretty clear in that the connector between the ultrasonic wand and the base unit were hopelessly frayed and degraded.
the frayed ultrasound wand cable
We tried to re-shield the cable from the ultrasonic wand using some tin foil. Then I decided that we needed to replace the connector where the wand plugged into the base circuit board. After much effort, we were able to desolder and remove the connector.
The USB style connector was in pretty bad shape. At least two pins were probably not consistently making contact.
Unfortunately, after visiting about six or seven different shops, we were unable to buy a replacement connector. Finally I decided it was time to put the original connector back into the circuit board. However, no matter what I tried, the connector wouldn't go back in cleanly. After an incredibly aggravating couple of hours, it was time for us to leave, and I had to accept the fact that the connector wasn't going back into circuit board properly. We tried turning the device on, but it no longer recognized the wand. With my tail between my legs, we went to hand it back to the doctor. It's hard to tell whether she was really upset or not, but she thanked us for trying and sent us on our way. I feel pretty guilty that we ruined their sensor, and now I'm consumed with trying to get them new one, which will apparently involve a trip to Managua at some point. In hindsight, I should have taken a much more conservative approach with this instrument since it was their only working one. I think my hubris got the better of me, and I really only considered the best case scenario. I will try to communicate this lesson to my students today. I think it can be instructive when students see their instructor fail, and try to learn from that failure. Perhaps some good will come of this.

Anyways, despite that, it has been a fairly successful few days, and everyone seems to be learning and having fun. Hopefully next week we will get to visit a facility in Managua where they collect broken medical equipment from across the entire country. I am really looking forward to that!
Our hard work was rewarded with a nice pile of coconuts which we had to learn to open ourselves with the hospital's machete!

1 comment:

  1. Very cool! I wish more of our students could get exposed to this type of stuff as freshman.