Interesting start. It hooked me enough that I'd like to know where it's going. I voted "In my opinion it needs..."
A few things that jumped out at me:
> "A man plays his guitar in a dusty diner, could be Mexico, Texas or anywhere in the Deep South of the dear old USA. Rock spews forth from a jukebox at the back, all Johnny Cash, Elvis Presley and all those other rockers no one remembers but is “Darn toot’n” all the same."
I would recommend rewriting this intro because there are a few things that didn't sit right with me.
First off, Mexico, Texas, and the Deep South are different places with their own flavor. Alabama has its own identity that's different than Georgia that's different than Texas. You might be better off describing it as a border town, somewhere near El Paso. That region of Texas is dry and dusty, whereas North Texas and the gulf region are very humid.
Whether you like their music or not I'd argue that Johnny Cash and Elvis Presley are icons in modern rock music, Elvis especially. I don't think it works to lump them in with other rockers that nobody remembers. I've never actually heard "darn toot'n" used in conversation outside of cartoons or spaghetti westerns and it feels a little bit forced to me.
> "Heart rate’s one twenty over eighty, beginning with a one sixty volt charge one…two…. Three Clear! No change, heart rates one eighty over sixty, upping to a two-hundred and ten charge! One… two... three… clear! No change. She’s crashing, upping to full 360 volt charge, one… two… three… clear! No change, she’s going into cardiac arrest! Beeeeeeeeeeeeeeeeeeeep! She’s gone, call it. Time of death Twelve PM."
Heart rate is measured in beats per minute. 120/80 would be the measurement for somebody’s blood pressure. (120/80 actually falls pretty much within normal limits.) They’re not going to administer the shocks until somebody’s gone into cardiac arrest, at which point heart rate should be zero and blood pressure should be negligible.
From the way it’s written it appears they’re trying to resuscitate her before her heart’s even stopped.
The other major thing that I’d recommend taking a look at is the way it’s written in present tense. Just a matter of opinion but I prefer to read in the past tense.
I do think you’ve got an interesting start and I’d like to see where it goes. Good luck!