Pacemaker Speech

JOANNE: Welcome to CBC with your host Joanne. Today we have three special guests to talk about their breakthrough in medical technology, the pacemaker. Our guests are Dr. Wilfred Bigelow, Dr. John Callaghan and electrical engineer, John Hopps!
JOANNE: Thank you for joining us Dr. Bigelow, Dr. Callaghan and Mr Hopps!
BIGELOW: Thank you for having us!
JOANNE: So before we begin to talk about your pacemaker, I 'd love to hear more about you guys.
BIGELOW: Well I am a cardiovascular surgeon and I served as a surgeon in World War 2 in the casualty clearing stations. That 's actually where I became interested in hypothermia and its effects on the body and I can thank that interest for the development of the pacemaker.
CALLAGHAN: I am also a

My fascination with cardiovascular instruments began when I attended the National Research Convention in Ottawa. I know then that I wanted to devote my career to developing these instruments.
JOANNE: Thank you, that was all very interesting. So, let 's begin to talk about the pacemaker. Why don 't you guys explain what a pacemaker is for those who don 't know?
HOPPS: A pacemaker is a small device that 's inserted into someone 's chest and helps those with arrhythmia, which is a condition where someone has an irregular heartbeat.
JOANNE: Very fascinating. So how did you guys come up with the idea of the

Ten years after the first pacemaker, small silicon transistors replaced the vacuum tubes which made the pacemakers small enough to be inserted into the chest of the patients. The pacemakers also needed to be charged, so the device was altered so it would take mercury-zinc batteries to last longer. Eventually the mercury batteries were replaced with lithium ion batteries which is what the modern pacemakers use, but the lifespan of the pacemakers is still quite short. Modern pacemakers are also the size of a USB and are much more complex than they used to be. They are now programmable to it the specific needs of the