Cause of Death Revealed for 9-Year-Old Who Was Placed Under Anesthesia for Dental Procedure

The origin of decease has been revealed for a 9-year-old woman who underwent anesthesia for a dental procedure earlier this year.

Silvanna Moreno, a Southern California third-grader, died connected March 18 hours aft room astatine Dreamtime Dentistry successful Vista, Calif., according to a caller San Diego County Medical Examiner's Office (SDCME) autopsy study obtained by PEOPLE.

Silvanna's origin of decease was listed arsenic methemoglobinemia successful nan mounting of caller nitrous oxide administration.

Methemoglobinemia tin hap erstwhile excessive amounts of nitrous oxide get into someone's hemoglobin (the macromolecule contained successful reddish humor cells that delivers oxygen to nan tissues) and origin hypoxia, truthful tissues do not person capable oxygen.

Nitrous oxide was among nan anesthetics Silvanna was administered during her procedure, according to nan autopsy report.

Silvanna's autopsy states she had room aft she complained of bony symptom successful October 2024, She was referred to Dreamtime Dentistry, which booked her for a March procedure. 

The time before, she had a fever but her symptoms resolved aft being fixed children’s Tylenol, according to nan autopsy report.

The time of her surgery, she complained of a headache “without appearing distressed,” according to nan report. She was administered anesthesia astatine 10 a.m. for a three-hour procedure.

Once she woke up, she was moved to a betterment room and past discharged, nan autopsy states. On nan measurement home, she was described arsenic being “out of it” and later was snoring heavy but was besides initially capable to unfastened her eyes and stand.

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Once Silvanna arrived home, she was carried wrong and remained dormant for astir 90 minutes earlier her snoring sewage noticeably quieter and slower, according to nan autopsy.

Her grandma past administered 2 abstracted readings of her bosom rate. After nan 2nd reading, she remained unresponsive and 911 was called astatine 4:46 p.m. section clip — astir six hours aft her getting anesthesia.

A dispatcher instructed nan grandma to administer thorax compressions while they waited for emergency unit to arrive.

She was taken to Rady Children's Hospital Emergency Department, wherever she was successful asystole — a information successful which nan heart's electrical strategy fails, causing nan bosom to extremity pumping, according to nan Cleveland Clinic.

Silvanna was administered respective life-saving strategies but was pronounced dormant astatine 5:44 p.m.

In a caller statement, Dr. Ryan Watkins — a board-certified dental anesthesiologist astatine Dreamtime Dentistry pinch complete 20 years of acquisition successful pediatric anesthesia — said, successful part, that methemoglobinemia is an "extremely uncommon information that tin hap pinch nitrous oxide administration," and that typically, erstwhile patients acquisition this condition, their "pulse oximetry readings will show abnormally debased levels successful nan 80s."

Watkins insisted that Silvanna "never exhibited" immoderate informing signs passim nan process and that her oxygen saturation levels continued to stay normal passim her recovery.

Ahead of nan procedure, they took a "thorough reappraisal of her aesculapian and dental history" and Watkins said that during nan procedure, they "maintained our modular of attraction pinch continuous monitoring by me."

Watkins went connected to opportunity that while nan mode of Silvanna's decease was ruled accidental, Dreamtime Dentistry is conducting a thorough soul review.

"We are committed to learning from this tragic arena and will instrumentality immoderate further information measures that whitethorn thief forestall specified occurrences successful nan future," Watkins added. "We widen our deepest condolences to Silvanna's family and inquire for continued respect for their privateness during this clip of grief."