For nearly a decade, a respiratory therapist was entrusted with caring for some of the most vulnerable hospital patients, but at some point, he started playing judge and executioner. Dubbed the “Angel of Death,” authorities insist he was no angel.
Crime + investigation
A Serial Killer Hid in Plain Sight While Working at a Hospital
Efren Saldivar was a respiratory therapist convicted in 2002 of murdering six patients and attempting to murder a seventh. Some suspect he's killed hundreds.
Getty ImagesPublished: August 13, 2026Last Updated: August 13, 2026
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A Killer Within
Efren Saldivar once saw a friend donning hospital smocks and decided he wanted that “cool” look, so he obtained his high school equivalency certificate and enrolled in a one-year respiratory care program at the College of Medical and Dental Careers in 1988. The following year, he was hired by Glendale Adventist Medical Center—now called Adventist Health Glendale—in California as a respiratory therapist (RT) at age 19.
Saldivar preferred the night or “graveyard” shifts, which tended to be calmer and have less supervision. He possibly killed his first patient within months of arrival. According to Saldivar’s initial confession—which he quickly retracted—he manipulated a patient’s breathing tube to cause suffocation.
Like Dexter Morgan, the fictional serial killer who developed his own “code of ethics,” Saldivar claimed that a victim needed to meet his criteria: A do not resuscitate order, unconscious and looking like they were “ready to die.” On a printout of a lung test, he jokingly wrote the doctor’s name as Jack Kevorkian in reference to the pathologist who was a euthanasia advocate and participated in assisted suicide.
Saldivar did not seek consent. He moved on to administering lethal doses of Pavulon or succinylcholine, drugs that paralyze the body and suppress breathing.
A fellow RT told hospital employee Bob Baker that Saldivar had a “magic syringe.” In April 1997, Baker went to the head of the pulmonary department and shared what he heard. They kept an eye on Saldivar and reviewed deaths on his watch. The conclusion: “Nothing unusual.”
One night, Saldivar’s colleagues decided to play a prank on him. They jimmied open his locker and found drugs that RTs are not authorized to administer, including succinylcholine. Because they could get in trouble for breaking into the locker, nobody spoke up.
Around that time, Saldivar began a romantic relationship with co-worker Ursula Anderson. They were sometimes the only two RTs in the hospital, which allowed them to pursue amorous endeavors. On at least one occasion, she gave Saldivar succinylcholine she found in the ICU knowing “that he was killing patients with injections of succinylcholine.”
On February 16, 1998, the hospital received an anonymous call from somebody trying to extort money for information about an employee who was killing patients. (His identity was later revealed as Grant Brossus.) After a two-week delay, hospital staff asked Glendale police to investigate.
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2 Confessions, 1 Recantation
Saldivar was questioned on March 11, 1998. He gave a full confession, saying, “There were a lot of terminally ill patients who were suffering. People who were hooked up to machines with no chance of recovery. I started to think it was cruel to leave them like that.” Police released him two days later, as prosecutors needed independent corroborating evidence. Saldivar quickly recanted his statement, claiming that he lied because he was depressed and feeling self-destructive.
A task force, led by Sergeant John McKillop, was formed to look into Saldivar’s initial claims. McKillop tells A&E Crime + Investigation, “He offered nothing to identify who he killed. He couldn’t recall any specific patients, so we didn’t have a patient to exhume based on what he said.”
Investigators needed to find traces of Pavulon or succinylcholine in exhumed bodies. The task force started with more than 1,000 patients who died within an hour of Saldivar's shifts while he was on duty during his nine years of work. They then chose to concentrate on Saldivar’s last two years, whittling down the list to 171 people. Fifty-four were cremated, therefore they were excluded. That left 117 cases to review. Twenty were considered suspicious.
A forensic chemist at Lawrence Livermore National Laboratory told investigators that succinylcholine would likely not be present in the remains and suggested the focus be on Pavulon. Six patients had traces of the drug in lethal doses; investigators then worked to rule out legitimate medical reasons as explanations for the findings.
Brian Kelberg, the deputy district attorney assigned to the case, was methodical to a fault.
“The experts that we were talking to would say Pavulon wouldn’t stay in their tissue for years, especially when they're in the ground for one or two years decomposing,” McKillop says. “He insisted that we pull every medical record of every patient or every person that we suspected was murdered back to when they were infants to prove that there was no Pavulon administered ever in their lifetime.”
That alone took upwards of a year.
Steve Cooley, who was the newly elected L.A. County District Attorney at the time of the investigation, gave the go-ahead to try the case. One of his first acts was to replace Kelberg with another deputy DA.
Saldivar was arrested on January 9, 2001. He confessed again, this time without a recantation, and revealed his motive. “We had too much work,” he told McKillop. “Only when I was at my wits’ end on the staffing, I’d look on the [patient] board. ‘Who do we gotta get rid of?’”
“After the final confession, we suspected he killed hundreds of people,” McKillop says.
Saldivar was charged with six counts of murder and one attempted murder. He pleaded guilty on March 12, 2002, and was immediately sentenced to six consecutive life-without-parole sentences plus 15 years to life for attempted murder. Saldivar is incarcerated at California State Prison, Corcoran.
“He was called the Angel of Death,” Cooley tells A&E Crime + Investigation. “That may have been a misnomer because he was no angel. They weren't mercy killings. He felt empowered by doing this. They didn’t need his mercy, because they weren’t gonna die. Who the hell appointed Efren Saldivar as God? He doesn’t get to decide that stuff."
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About the author
Eric Mercado
Eric Mercado was a longtime editor at Los Angeles. He has contributed to The Hollywood Reporter, Capitol & Main, LA Weekly and numerous books. Mercado has written about crime, politics and history. He even travelled to Mexico to report on the Tijuana drug cartel and was a target of a hit on his life by a gang in L.A.
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Citation Information
- Article Title
- A Serial Killer Hid in Plain Sight While Working at a Hospital
- Author
- Eric Mercado
- Website Name
- A&E
- Date Accessed
- August 13, 2026
- Publisher
- A&E Television Networks
- Last Updated
- August 13, 2026
- Original Published Date
- August 13, 2026
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