The woman, who suffered from chronic obstructive pulmonary disease (COPD), had undergone a bowel operation when she suddenly had trouble breathing.
Tests revealed she had low levels of oxygen in her blood, at which point she was administered oxygen.
Several days later, however, medical personnel realized she had been receiving too much oxygen considering her respiratory condition, and the dose was lowered.
The woman was then moved to intensive care and put on a respirator, with further tests revealing she now had elevated levels of carbon dioxide in her blood.
Her condition failed to improve and she died later that day.
The incident has since been reported to Sweden's National Board of Health and Welfare (Socialstyrelsen) in accordance with Sweden's Lex Maria laws, the informal name for regulations governing the reporting of injuries or incidents in the Swedish healthcare system.
According to the Sörmland County Council, which has overreaching responsibility for administering healthcare in the county, the incident has prompted a wider review of oxygen treatment for patients with COPD.
"The aim and goal of the analysis is to highlight and secure procedures for oxygen treatment of COPD patients and reduce the risk of similar incidents," the County Council wrote in a statement.
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