|MadSci Network: Medicine|
Three drugs, each with a distinct and main purpose. After positioning the convicted individual on the gurney/bed, a doctor or nurse sets up iv (intravenous) line. This is the route of administration for the drugs, and provides direct access to the circulatory system. When a drug is injected iv, it travels with the venous blood through the veins directly to the heart and lungs. From here the blood is pumped throughout the body. It is a very fast way of delivering drugs - drugs injected iv will reach the brain in approximately 10 seconds. Here are the drugs and their purposes, in sequence: First, a barbiturate is administered to anesthetize the person (make them unconscious). Barbiturates were originally (and still remain) used for surgery. There are a couple of specific drugs that are probably the 'drug of choice': thiopental (sold as Pentothal) is easily dissolved in sterile water, as is methohexital (Brevital sodium). Following the iv administration of the barbiturate, the person loses consciousness in about 10-20 seconds. Under other circumstances, the anesthesia would probably last 20-40 minutes. It should be noted that barbiturates in general are often poor analgesics (pain relieving). Thus, although the individual may lose consciousness, pain perception may be unaffected. Typically in surgical procedures, at least two drugs are administered - an anesthetic and an analgesic (or one drug that can produce both). Second, a neuromuscular blocking agent is administered to paralyze the person. Often the drug administered is similar to curare. Curare has a long and colorful history. It was used by various South American cultures (around the Amazon and Orinoco Rivers) as a poison for arrow tips that were used to hunt and kill animals for food. Hunted animals died from paralysis of the skeletal muscles which are used throughout the body, but perhaps most importantly in breathing. Use of curare derivative in executions results in a rapid paralysis of most major muscle groups. Initially, effects are observed in small rapidly moving muscles (eyes, fingers) followed by larger ones. Eventually, the diaphragm is paralyzed, resulting in cessation of breathing. Finally, a lethal dose of potassium chloride is injected. Potassium is the main positively charged ion inside of all of our cells that is essential for our day-to-day living. Banana's are a very good source of potassium. However, like many things, too much of a good thing can be bad for you. If you consult a biology or physiology textbook you can learn about how important it is to maintain a balance in ions. The lethal dose of potassium chloride produces hyperkalemia (too much potassium; you ask why the word 'kalemia'? -- potassium's chemical symbol is K). One of the main effects of hyperkalemia is a change in the electrical activity of the heart. The lethal dose administered basically stops the heart. So, in summary, the drugs used knock them out, stop the breathing, and then stop the heart. Death. For additional information on: the processes involved, the specific drugs, or about lethal injections Consider consulting: a. Physiology or cardiology textbooks b. Pharmacology textbooks (Goodman and Gilman's The Pharmacological Basis of Therapeutics is the best out there) c. Amnesty International (http://www.amnesty.org/) has lots of information, albeit from a biased perspective Hope this helps you out.
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