June 21, 2010
I haven’t been giving enough context in my posts I think. Just as a recap. I am working with Yiwen at St. Gabriels Hospital, which is in Namitete, a rural farming village, 45 minutes outside the capital city of Malawi. Jasper and Tiffany are also working here for BTB.
One of our devices that we brought with us was donated, a pediatric transilluminator called the “Veinlite Pedi”. Transilluminators are used to shine light, usually red through the skin to help visualize veins. The deoxygenated heamoglobin in veins absorbs light around the wavelength of red light, so when the light is shined on the skin, veins should appear dark. Finding veins helps reduce blind and unsuccessful sticking when starting a cannula to deliver IV fluids. Starting IVs successfully in infants can be particularly challenging due to their thin veins. The same can be said for adult patients suffering from severe diarrhea, since the dehydration shrinks the veins. Also, it is difficult to see veins in obese patients due to obstructing subcutaneous fat. These problems are compounded in our particular setting since it is even harder to see veins in dark skinned patients.
During this past semester I worked in a team developing a transilluminator which would be cheaper than the $100 it costs to buy a Veinlite. We were envisioning a handcrank device, so there would be no power requirement, to fuel red LEDs. In the end, the small LEDs didn’t turn out bright enough, so before the internships started I made several which have a large 1 Watt red LED (really bright for an LED) and are battery powered. Those transilluminators went to other sites and Yiwen and I got the Veinlites.
In the pediatric ward, the nurse tried out the Veinlite on three patients. He had only just be taught how to use it by the other nurse, whom we had demonstrated it to in the past week. On the first patient, he tried with the light shield, and saw a vein, but starting the cannula (the stick) wasn’t successful. Then he tried again after adding the neonatal adapter piece (to reduce the amount of light being used) and the stick using this mode was successful. Next he tried on an older child, 5 ½ years, and found the vein with the light shield in place and stuck successfully. On the final patient of the day, he used the Veinlite with the light shield, saw a good vein, but the stick did not work. When he tried again without using the light he was successful. One of the difficulties was deciding whether to try and hold the Veinlite in place while performing the stick, or to set it down once the vein has been spotted and try to remember the location. When my teammates and I were designing our prototypes, when had hoped to incorporate some sort of strap to help alleviate this problem.
It is hard to tell based just on this sample, how useful the transilluminator is. We don’t want the nurse to feel pressured to use the device, if he doesn’t feel comfortable using it, or if it doesn’t seem to help. I imagine there is a bit of a learning curve to using the device. Ultimately, starting an IV seems to be pretty hard, as well as a valuable skill. We decided that perhaps the Veinilite would best be used as a back up when veins are particularly difficult.
We also have an adult sized Veinlite, but it is not clear where it will be most useful yet.