Nurses and respiratory therapists on the night shift could go in and out of patients' rooms without anyone seeing them, since during those quiet hours from 11 p.m. to 7 a.m. the halls were usually empty.  Besides that, people doing their medical routines would hardly come to anyone's attention.  After a while, it all becomes a blur and each person takes for granted that everyone else is doing his job---and nothing more.

Yet some patients would be awake at night and needing attention—even demanding it.  A few were lonely and wanted some company, but some were chronic complainers and wanted a treatment any time, day or night.  It was like they were in a resort hotel with staff at their beck and call, and not all of the hospital staff appreciated that.  Especially when such patients showed up in the hospital time and time again.

One of these was a woman named Jean Coyle.  On February 26, 1997, she pressed her button to get some help and Saldivar responded---again.  He went in and as Coyle recalled the incident in the Los Angeles Times, she blacked out.  She did not know how it happened, but she came to and didn't give it another thought.  Not until she heard about what was going on in that hospital.  Then she viewed her experience in a different light.

In April that same year, one of the other respiratory therapists, Bob Baker, suggested to his boss that Saldivar was doing things to patients at night, injecting them with something.  It isn't unusual in hospitals that people spread rumors about others, especially when patients are dying in ways that seem inexplicable.  Yet there had to be proof.  Without that, no one would be suspended or fired. 

At that time, John Bechthold was head of the department and he did not like Saldivar.  Neither did the therapist who had squealed.  The easy thing would be to turn him in, but since their personality clashes were known, it might look like he was undermining a guy just because he didn't like him.  Bechthold needed more than innuendo, so he told another supervisor what he had heard and together they beefed up their vigilance.

Often when a health care worker is viewed as an "angel of death," or a medical professional who kills patients, a pattern begins to show up on that person's shift.  Genene Jones, working on the children's ICU in a Texas hospital, had a high incidence of respiratory arrests among children over whom she had watch and who had entered the hospital without heart problems.  It turned out that she had been injecting them with drugs like succinylcholine chloride, a muscle relaxant that suppressed breathing and could paralyze a person, because she enjoyed the excitement of an emergency.  She also acted strangely around dead babies, yet the hospital administration did only a lax investigation.  Then she moved on to a one-doctor clinic, and the constant cardiac arrests and seizures finally brought attention to the problem, but only after one child died.  She was convicted of murder and no one knows how many other babies she had killed.

In Saldivar's case, the records on his shift indicated nothing unusual.  If he was doing something to patients, he was being careful. 

However, to those who worked closely with him, his shifts appeared to be jinxed.  They would talk about patients who needed to die, and then that person died.  Sometimes several people died in one night.  Occasionally the other therapists joked that Efren had the magic touch.  What he had was the "magic syringe."  But eventually he got careless.