Nicaragua - Day 27

We finally reached the end of the program. Well, at least the first month, which is where my contribution ends. The last week was filled with a handful of interesting labs. One of them involved us picking through a big box of old medical equipment that someone had left in the school supply closet for us to look at. We took apart a blood pressure cuff, a nebulizer, and a few other odds and ends. The nebulizer was fun because it seem to follow the same basic pattern that all other suction and pressure devices follow. We tried to strip it down to its barest minimum, but were foiled by a lousy screw that stripped itself into smithereens and would not budge. In another lab, the students programmed a PIC to interface with a thermal probe to measure temperature and to set an alarm in case the ambient temperature was too low or too high. The students had to attempt to calibrate the system by mapping the arbitrary units from the analog to digital converter into degrees Celsius. The thermal sensor wasn't exactly the most accurate gizmo ever, so it was a challenging lab, but still enlightening. One highlight was the various methods students took to raise the temperature of their probe in order to calibrate it. One team put their probe in a ziplock bag and dipped it in the coffee pot only to discover that their ziplock bag was not exactly waterproof!

A thermal probe unit in a very leaky ziplock bag.

Yesterday, Friday, I took three students back to Nandaime hospital where we attempted wh tie up some loose ends. First thing on the agenda was the fetal doppler unit which I screwed up a couple weeks ago. Thanks to some friends of ours who flew in Thursday night from the United States, I had brand new mini USB Type B connectors in hand, and we were able to desolder the old connector and put in the new one without too much fanfare. unfortunately, I think we must have damaged some of the traces on the board during our first attempt to fix it and we were unable to get it working. I tried to guess where the broken traces might be so that I could short them but no luck. Well, at least we gave it everything we had. We also started working on an electric heater. We added a power cord (which somebody had cut off) but that didn't seem to be the only problem. We didn't have time to get to the bottom of it, but I'm pretty sure the heating coil needed a massive scrub because it was completely rusted through. For comic relief, we were handed a floor lamp that looked pretty new but we were told it didn't work. In trying to diagnose the problem, I happened to pull on one wire and the whole lamp snapped into life. I guess we got lucky! As the director of the hospital wryly noted, well at least you fix the lamp today. A bit of a hollow victory, but a victory none the less.

My biggest "engineering" victory of the week was replacing a light switch at my old homestay. You take your victories where you can!

The students are officially sufficiently trained to spend a month working in hospitals. They are a great bunch, and I expect they will all learn something and find some way of being of service to their various hospitals. I'm looking forward to keeping up with their exploits once I'm back home. And naturally, I take credit for all their successes and none of their failures :)

I'm off to the beach for a few days before heading back to Philadelphia. See you all soon.