The Nonin 9500 pulse oxymeter was used to check the pulse and blood oxygen level of Jackson while he was under the powerful anesthetic propofol, according to CNN.
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The machine was designed "for spot checking on vital signs" said a Nonin executive. The witness also said that the machine was also "specifically labeled against continuous monitoring."
Testimony took a surprise turn to toward praising Murray. A former patient, Robert Russell, took the stand to testify that Murray came to his rescue and essentially saved his life after suffering a heart attack.
"He gave me advice on exercise, on eating, just how to live my life, doing away with pressure and stress that I believe I thrived on in the business world," he said, but went on to mention feelings of abandonment once Murray dropped him as a patient for Jackson.
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One of the first emergency responders, Richard Senneff, took the stand and said that Murray didn't indicate that propofol was given to Jackson.
All of today's testimony was all over the place -- some tried to pin Murray, while others praised his medical efforts.