Since there are times when there is a rattle behind every bush, this is not a trivial question. I always carry a Sawyer Extractor as do others, but I can't find anyone who has actually needed to use it. It's effectiveness has been questioned, but I figure it's better than nothing. I carry a cell phone, too. There may or may not be a signal. If there is, call SAR and hope to be coptered out. The universal advice is get medical help FAST! I found this advice at
http://www.fda.gov/Fdac/features/995_snakes.html
Many health-care professionals embrace just a few basic first-aid techniques. According to the American Red Cross, these steps should be taken:
Wash the bite with soap and water.
Immobilize the bitten area and keep it lower than the heart.
Get medical help.
"The main thing is to get to a hospital and don't delay," says Hardy. "Most bites don't occur in real isolated situations, so it is feasible to get prompt [medical care]." He describes cases in Arizona where people have caught rattlesnakes for sport and gotten bitten. "They waited until they couldn't stand the pain anymore and finally went to the hospital after the venom had been in there a few hours. But by then, they'd lost an opportunity for [effective treatment]," which increased the odds of long-term complications. Some medical professionals, along with the American Red Cross, cautiously recommend two other measures:
If a victim is unable to reach medical care within 30 minutes, a bandage, wrapped two to four inches above the bite, may help slow venom. The bandage should not cut off blood flow from a vein or artery. A good rule of thumb is to make the band loose enough that a finger can slip under it.
A suction device may be placed over the bite to help draw venom out of the wound without making cuts. Suction instruments often are included in commercial snakebite kits.