Transcript for Could ammonia smelling salts be masking concussions?

??? Time for the "Weekend download." We have a good one. Chief medical correspondent Dr. Jen Ashton is here with fascinating new information. Including studies on surgery. Let's start with the phew report in "ESPN the magazine" that estimates as many as 80% of NFL players are using smelling salts after a hard hit. This is a problem? Not good. Have you smelled one of those? No. You have to remember. You can snap or break them. The sole use is to try to counteract the feeling op wanting to faint. You snap it. It emits a noxious smell. It produces a powerful reaction in our system causing swelling in the tissue. And necrosis, our medical ling goe for cell tissue death. It's probably causing significant damage here. Of course there are concerns. Sit masking the sips of symptoms of a concussion. Will it trickle down to the youth level. No Bueno in my mind. Safe for the rest of us. If you're about to INT, absolutely. Let's talk about the studies on surgery. One is a new study. It says it matters when you're getting heart surgery whether it's in the morning or afternoon. Right, small but interesting study. Comparing patients with elective cardiac surgery. Morning versus afternoon group. The afternoon group had lower complications. They're not sure why. Probably not about the surge call team. Maybe more intrinsic with the patient. Don't change your O.R. Time yet. But it's something we're looking into. Possibly in the future. Another study that looks at our fears around surgery as it pertains to pain. This study looked at people having general versus rege Yan anesthes anesthesia. They way overest matded their post-op pain. You have heard about placebo. The flip side is nocebo. If you expect a high instance of pain, it will happen. Talk to your anesthesiologist. The likelihood of pain is low with all the medications we have. The treatment of pain in the surgical time period is of utmost priority to us. That is reassuring. Always great to see you. Appreciate it. Coming up next, "Pop news" with Adrienne Bankert.

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