An elderly female patient at a hospital in Yamanashi Prefecture died after a nurse erroneously administered a drug to her without diluting it in intravenous fluid, it was learned Monday.
Ko Ozawa, director of Yamanashi Red Cross Hospital in the town of Kawaguchiko, admitted that the nurse erred but said it is unclear whether the patient's death on Saturday was caused directly by the mistake.
Police are questioning the nurse and investigating the cause of death to determine whether to pursue charges of professional negligence.
The patient, a Yamanashi Prefecture resident in her 70s, was admitted to the hospital last Tuesday, suffering from congestive heart failure.
After blood tests Saturday morning showed her potassium level was low, her doctor told the nurse to dilute 20 ml of potassium chloride in an intravenous solution and slowly administer it.
But the nurse injected the undiluted drug directly into the patient's vein through an intravenous tube. The woman shortly suffered an irregular heartbeat and died about an hour later.