Silvanna Moreno, a vibrant 9-year-old from San Diego, tragically passed away just hours after undergoing a dental procedure under general anesthesia at Dreamtime Dentistry in Vista, California.

The surgery took place on March 18 after Silvanna was referred due to tooth pain and dental anxiety. According to the autopsy, she had a mild fever and headache beforehand but was cleared by her mother on pre-op forms as “not sick.” After surgery, she was released home but fell asleep in the car and never woke up.

Her condition worsened at home, and she was rushed to Rady Children’s Hospital. Despite emergency efforts, Silvanna was pronounced dead at 5:44 p.m. Her cause of death was listed as methemoglobinemia, a rare blood disorder linked to nitrous oxide that affects oxygen delivery.

Dr. Ryan Watkins, who treated her, stated: “We are heartbroken and are reviewing every aspect of her care.” A GoFundMe page described Silvanna as “the sunshine in every room she entered.”

Her sudden passing has raised concerns about pediatric anesthesia safety and pre-procedure illness disclosure.