Researchers and students at Massachusetts Institute of Technology, Cambridge, are trying to change how medical equipment is sterilized in remote clinics using sunlight, an abundant commodity. Their pilot project, conducted in Nicaragua has begun to show promising results.
To care for a nation of six million, there are 11 hospitals, dozens of health centers, and about 1,300 “health posts” that provide emergency care and obstetric services. Most of the posts, are staffed by nurse practitioners, and either lack equipment to sterilize surgical tools and bandages or have kerosene-powered autoclaves. Often, the nurses must boil tools or swab them with alcohol, or even travel long distances for proper sterilization at larger centers or hospitals.
An MIT team, called the Little Devices group, has developed a solar-powered autoclave, called the SolarClave, that can be built and repaired using locally available parts and materials. The device would cost less than existing kerosene or electric sterilizers and require no fuel or power.
Rather than have teams of engineers develop an invention, and then try to get developing countries to use it, the research group emphasizes an interactive approach in which end-users play an integral role in developing and refining a product.
In the more than three years the SolarClave has been under development, feedback from the users in Nicaragua has led to making the device simpler, easier to build, and less prone to failure by reducing the number of connections where hot steam might leak out, and increased the number of components available in Nicaragua.
The system uses an ordinary pressure cooker, suspended directly over a reflector, to contain the tools and materials being sterilized. The reflector is made up of an array of small pocket mirrors, readily available in Nicaragua and less prone to damage. The upgraded system is now in use at three test locations in Nicaragua; by this summer, the team plans to put several more units in use.
The system delivers heat and pressure that meet sterilization standards set by the U.S. Centers for Disease Control—standards widely adopted by health agencies around the world. Under a clear sky, the system takes about an hour to heat the pressure cooker to the required temperature of 121 C, and then 20 minutes to carry out the sterilization. Typically, at a village health post, the device would run through this cycle about three times a week.
