The cause of death was revealed for Girl, 9, which was placed during anesthesia at dentists

The cause of death has been revealed to a 9-year-old girl who underwent anesthesia for a dental procedure Earlier this year.

Silvanna Moreno, a third grade in southern California, died on March 18 hours after the operation at Dreamtime Dentistry in Vista, California, according to a new San Diego County Medical Examiner’s Office (SDCME) autopsy report obtained by People.

Silvanna’s cause of death was listed as metemoglobinemia in the setting of the latest nitric oxide administration.

Metemoglobinemia occurs when excessive amounts of nitric oxide enter someone’s hemoglobin (protein in red blood cells that deliver oxygen to the tissues) and cause hypoxia so that tissues do not get enough oxygen.

Nitric oxide was among the anesthetics of Silvanna was administered during her procedure, according to the autopsy report.

Silvanna’s autopsy says she had surgery after complaining about toothache in October 2024, she was referred to Dreamtime dentistry, which booked her for a Tuesday 18 March, procedure.

The day before, she had a fever but her symptoms were resolved after receiving children’s tylenol, according to the autopsy report.

The day for her surgery, she complained about headaches “without seeming worried,” according to the report. She was administered anesthesia at 10 for a three -hour procedure.

When she woke up, she was moved to a recovery room and then released, says the autopsy. On the way home, she was described as “out of it” and later snore heavy but could also initially open her eyes and stand.

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When Silvanna arrived home, she carried inside and remained asleep for about 90 minutes before her snoring became noticeably quieter and slower, according to the autopsy.

Her grandmother then administered two separate readings of her heart rate. After the second treatment, she did not remain responding and 911 was called at 16:46 local time – about six hours after she received anesthesia.

A sender instructed grandma to administer chest compressions while waiting for emergency personnel to arrive.

She was brought to the Rady Children’s Hospital Emergency Department, where she was in Asystol – a condition where the heart’s electrical system fails, which caused the heart to stop pumping, according to Cleveland Clinic.

Silvanna was administered several life -saving tactics but pronounced dead at 17:44

Dreamtime did not immediately respond to a call and e -post that sought comment on the autopsy.

In a previous statement, a representative of Dreamtime’s Dr. Ryan Watkins, partly “we are deeply saddened by the tragic passing of our young patient, who occurred several hours after her completed dental procedure.”

“Throughout the procedure, she was continuously monitored by our dentist anesthesiologist, who … has over 20 years of experience successful to administer general anesthesia on children, without complications observed,” continued the statement.

“After the procedure was released (silvan) in stable condition with stable vital signs and protective reflexes intact-Her mother’s care, following our standard particol after anesthesia,” according to Dreamtime’s previous statement.

“The safety and well -being of our patients has always been and remained our highest priority,” said Watkins, leaving, “our hearts break for the family during this unthinkable sadness, and we extend our deepest condolences when we maintain our focus on supporting the family and cooperate fully with the medical investigation.”