Final answer:
Tocilizumab would be an appropriate therapy for the 83-year-old woman with COVID-19 based on the recommendations of the Surviving Sepsis Campaign.
Step-by-step explanation:
Based on the recommendations of the Surviving Sepsis Campaign, the appropriate therapy for the 83-year-old woman with COVID-19 would be Tocilizumab. Tocilizumab is a medication that can be used to treat severe COVID-19 cases with rapid clinical decline and low oxygen levels, as it works by reducing inflammation in the body. Other options mentioned in the question, such as Hydroxychloroquine, Intravenous immunoglobulin, and Acetaminophen, are not currently recommended for COVID-19 treatment by the Surviving Sepsis Campaign.