Desperate struggle to save Hayden Panettiere's life after drug overdose revealed in newly-released 911 call audio

The battle to save Hayden Panettiere's life after her overdose has been revealed in newly-released 911 audio.

Panettiere died aged 36 on August 16 at a residence in Greenville, South Carolina, from the 'toxic effects' of multiple drugs – including fentanyl. Her death was accidental.

Her boyfriend Brian Hickerson and his brother Zach were present at the scene when she was pronounced dead. 

The audio, obtained by CBS, begins with Zach exclaiming 'oh God, oh my God!' as he waits to speak with dispatchers.

Zach says, 'I walked in after church to my brother and his girlfriend's apartment and she's unconscious.' He adds that Brian woke up but Panettiere did not.

Zack says that Panettiere is not breathing. Dispatchers then ask Zack if he has a defibrillator and he questions whether an apartment complex would have the life-saving equipment.

He and Brian are instructed to 'start CPR' as someone exclaims in the background. 

One of the brother is instructed to put his phone on speaker - while the dispatcher gives instructions. He is told to breathe into Panettiere's mouth and give chest compressions. 

Tension is heard rising on the audio clip as the dispatcher instructs the brothers to lay Panettiere 'flat on her back and remove anything from under her head.'

As the dispatcher pauses, one of the brothers exclaims, 'what do we do!'' before instructions continue. 

'Oh my god! I know how to do this! How many times!', one of the brothers calls out during the CPR instructions, before a shout of 'come on!' is heard in the background.

Panettiere is survived by Kaya, whom she welcomed during her nine-year romance with ex-fiance Wladimir Klitschko, 50. 

In 2018, Panettiere signed full custody of her daughter, Kaya, to her ex amid her battle with postpartum depression and addiction and Wladimir moved the toddler to his native Ukraine.  

Panettiere began acting as a child, appearing in soap operas, then gained wider recognition for her role in the 2000 sports drama Remember the Titans with Denzel Washington, and as the voice of Dot in Pixar's 1998 film A Bug's Life. 

Panettiere later found fame playing cheerleader Claire Bennet in the superhero drama Heroes before starring as country singer Juliette Barnes for six seasons on Nashville.

She earned two Golden Globe nominations for best supporting actress on the show, while her singing produced 11 entries on the US Billboard Hot Country Songs charts.

Panettiere's film credits include 2006's Bring It On: All or Nothing, the comedy-drama film Raising Helen, and appearances in Scream 4 and Scream VI as Kirby Reed.

This is a developing story. More follows.