Tuesday, September 1, 2009
I960: Kiil dialyzer
• 70 pound flat plate. Their large surface areas were covered with by sheets of cellophane
• After each treatment, the membranes were cleaned and stored in a chemical bath (formaldehyde) or the plates were taken apart and the membranes replaced
• Rach comer of the dialyzer had to be uniform and "torqued down" - a lengthy task called "building a dialyzer". i Treatment took up to 14 hours, 3 times a week.
• Also developed by Dr. Willem Kolff.
• First to be mass produced
• Cut treatment time to 8-10 hours
• A membrane supported by a mesh screen coiled around a central core
• Primed with a large amount of blood, set in a holding container called a canister, and bathed with dialysate
• Sterile and disposable - very costly.
Mid 1960s - Cuprophane - Gambro flat plate
• Small, 30 inches long, with many layers of membranes in pair. Each pair of membranes formed an envelope.
• During a treatment, blood flowed between the pairs of membranes, and dialysate flowed around the outside.
Late 1960s- small, lightweight, hollow fiber dialyzer
• Blood flowed through the insides of the fibers - thousands of tiny hollow tubes the size of hairs.
• Dialysate flowed around the outside of the fibers
• Much improved over the years- is the only type on the market today.
Advances that made dialysis more safe and reliable:
• Better membranes that are more compatible with the tissues of the human body (biocompatible) -increase treatment comfort for the patients
• Machine alarms and automated functions in the machine help protect patients from harm