The actress died in a fiery car crash on Aug. 5 in Los Angeles.
The Los Angeles County Department of Medical Examiner-Coroner's Office has released Anne Heche's final autopsy, and the 12-page report makes it clear that while the actress did have cocaine in her system, it did not contribute to her death.
According to the autopsy report, obtained by ET, a toxicology test showed the presence of benzoylecgonine, an inactive metabolite of cocaine, meaning there was no evidence of impairment by illicit substances at the time of the crash.
The urine toxicology results also detected medications given to her after she was treated at the hospital, including the powerful synthetic opioid fentanyl. The fentanyl traces are "consistent with therapeutic use." The results also showed prior use of marijuana, but not at the time of her injuries.
The final autopsy report also confirmed her cause of death -- smoke inhalation and thermal injuries. The autopsy report showed a sternal fracture due to blunt trauma, which significantly contributed to her death. Per the report, the sternal fracture she sustained made it extremely painful for her to breathe while she was trapped in her vehicle following the fiery Aug. 5 car crash in the Los Angeles neighborhood of Mar Vista.
The sternal fracture further complicated oxygenation and therefore also significantly contributed to her death. A CT scan of her brain showed "diffuse hypoxic injury with evidence of herniation." She suffered an anoxic brain injury due to lack of oxygen.
The report also showed that 40 percent of Heche's total body surface had first-degree burns. It took nearly 60 firefighters to rescue Heche from the wreckage, and firefighters couldn't get to her for 45 minutes following the horrific car crash.
Heche was pronounced brain dead on Aug. 12 and was "peacefully" taken off life support two days later so that her organs could be donated.
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