How common is the use of papaverine in organ harvesting?

On May 23 a kid from a local high school died at a party. The coroner found that the blood-alcohol level was .03, and that there was an obscure drug called “papaverine” in the kid’s system. The coroner’s report said that the kid died from choking on his own vomit, and that the vomiting was caused by an interaction of alcohol and papaverine.

Now it turns out that kid donated his organs, and that papaverine was administered post-mortem when the organs were harvested. Here is a news story about it.

My questions are: How common is the use of papaverine in harvesting organs? Is this something a coroner should be expected to know?

Also, according to Wikipedia, papaverine can be used for crypreservation of blood vessels. Is that why it would be used when harvesting organs?