Nurse poisoned at least 20 ailing patients so they would die during someone else's watch

Ryan W. Miller | USA TODAY

A nurse in Japan told police that she sped up the deaths at least 20 patients to avoid having to tell families that their loved ones died while she was working, local media reported.

Ayumi Kuboki, 31, was arrested Saturday for the death of Sozo Nishikawa, 88, who was poisoned in 2016 with an antiseptic at Oguchi Hospital, The Asahi Shimbun and The Japan Times reported. According to the two Japanese news outlets, Kuboki told investigators that informing families of a patient's death was a burden, and a task reserved for the nurse on duty.

In order to avoid the responsibility, Kuboki said she targeted patients near death so that they would die at a time when another nurse would have to tell the family, The Asahi Shimbun and The Japan Times reported.

The Asahi Shimbun reported that police believe Kuboki may have targeted patients who were not near death, too.

Nishikawa died on Septemeber 18, 2016, from what doctors initially ruled as natural causes. Two days later, his hospital roommate Nobuo Yamaki, 88, also died.

According to The Asahi Shimbun, another nurse noticed bubbles in Yamaki's intravenous drip bag. An autopsy found high levels of an benzalkonium chloride, a disinfectant, in his body, the Japanese news outlet reported.

Police then began investigating Nishikawa's death, who they then determined died of poisoning from the same antiseptic. At least two other patients were found with benzalkonium chloride in their bodies around the time of their death, The Asahi Shimbun reported.

Kuboki has admitted to the two deaths,The Asahi Shimbun reported and told investigators she injected the antiseptic into intravenous drip bags that treated at least 20 patients, and at least 10 other bags were found with small puncture holds, The Japan Times reported.

At least 48 patients died at the Yokohama hospital in a three-month span ending in September 2016, when authorities began investigating Nishikawa's and Yamaki's deaths.

Kuboki initially denied the killings. Police initially suspected one of the nurses on the floor had information about the deaths, but Kuboki told The Asahi Shimbun, "I have worked hard to help patients die in peace, so I was shocked by the incidents."

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