Paramedic: Dr. Murray's Answers 'Didn't Add Up'

Day four of the Michael Jackson death trial, with Dr. Conrad Murray facing involuntary manslaughter charges: In the morning session, a paramedic dispatched to Jackson's Beverly Hills home on the day he died testified that Murray was "frantic" at the scene and was initially reluctant to answer questions when he arrived in the pop star's bedroom to assess the situation and begin treatment.

Paramedic Richard Senneff said he arrived at the home about five minutes
after his fire station received the medical call. He said he
immediately observed in Jackson's bedroom that the patient was
underweight, had an IV hooked up to his leg and an oxygen tank and
medicine vials were visible in the room.

Senneff said he asked Murray
several times about any underlying health conditions Jackson had or
whether or not medications had been  administered. He said Murray
initially did not answer his questions. "He said, 'nothing. He has
nothing,'" Senneff testified. That, the witness said, "did not add up to
me."

The paramedic testified that eventually Murray told him the patient was being treated for exhaustion and dehydration and that the only medication administered was the sedative Lorazepam. Senneff -- one of four paramedics who attempted to revive Jackson -- also testified that when he returned to Jackson's bedroom after Jackson had been removed, he saw Murray gathering items from the room and putting them in a bag.

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Earlier, a representative from the company that made a medical device used by Murray told jurors the equipment was not adequate for continuously monitoring patients. The witness -- Nonin Medical's Bob Johnson -- said the $275 device monitors the pulse and blood oxygen levels. But Johnson said the particular model Murray used did not have an audible alarm and was not intended for continuous monitoring of patients. "If you aren't looking at the screen when the machine is used, it's useless."

Also taking the stand Friday morning was Robert Russell, a man treated by Murray in Las Vegas after he suffered a heart attack. Johnson testified that he initially felt like he "was getting the best care in the world" and credited Murray with saving his life. But he said he later became frustrated when the doctor became increasingly hard to reach and he couldn't get answers about his own treatment.

Johnson said he called Murray's office on June 25, 2009 -- the day Jackson died -- and demanded to speak to the doctor. Records show Murray left him a voicemail at 11:49 a.m. and prosecutors are using that information to show that Murray was on the phone in the moments before he realized Jackson was unconscious.

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Murray is accused of involuntary manslaughter, with the prosecution arguing that he gave Jackson a lethal dose of the powerful sedative propofol. The defense will argue that Jackson was a drug addict who self-medicated himself.

Stay tuned to ET for continuing coverage of the Jackson death trial.