Hi! I'm a CRNA and would be pleased to help you with your questions. For more information check out the following link:
http://aana.com/patients/having.asp
I suspect that you are writing fiction, rather than having questions regarding an upcoming anesthetic, etc. Anesthetics are given to effect, that is, there is no "usual dose" given, rather a range is stated in texts. We make decisions concerning dosage by considering the patient's physiology, disease process, length of surgery, etc. If we give other drugs, like a benzodiazepine (e,g, midazolam) or an opiod (eg fentanyl), it reduces our induction dose of propofol. Most nurse and physician anesthetists give a combination of drugs, rather than just propofol for induction. That said, theoretically, a healthy 120 pound teen, after being given 50 to 100 micrograms of fentanyl, would usually require between 120 and 200 mg of propofol for induction, prior to placing a tracheal tube. We would also add a muscle relaxant to facilitate the intubation process. Given an "easy" airway, my choice would probably be rocuronium, provided that the case would last about an hour. Any anesthesia text can give you dosage ranges for muscle relaxants, so I won't bore you.
Security of controlled substances is our responsibility. Each hospital pharmacy and anesthesia department has policies and protocols to prevent diversion of controlled substances. Most have a sign-out system of some sort...the CRNA signs out the drugs anticipated to be used in the case. (S)he notes the amount signed out, the patient's name, time, OR room, attending physician, etc. When the drugs are used, it is noted on the anesthesia record..a flow sheet of events as they occur in anesthesia. At the end of the case, any unopened controlled substances are returned to the pharmacy or place where they were signed out (some hospitals have a machine called a Pyxis, a computerized device that signs out the drug(s) to the CRNA, and allows them to be returned unopened). If a partial amount is not used, most hospitals require at least one witness, generally an RN or another anesthesia provider, to note on the narcotic record when, where and how much was wasted. Pharmacists audit the anesthesia records and compare the amount administered and wasted to the records. Any discrepency is immediately dealt with. When in doubt, the anesthesia provider may be asked to submit blood or urine samples to verify that (s)he did not administer it to themselves. Intraoperative monitoring includes B/P, EKG, pulse oximetry, and may include gas analysis (both anesthetic agent inhaled and exhaled, plus carbon dioxide) We infer anesthetic depth by stability of vital signs. There is a device called a BIS monitor that gives us a real number associated with depression of EEG (cortical) function. WE infer anesthetic depth from that as well. Giving anesthesia, however, is analagous to flying a plane without an altimeter. Only BIS gives us the info we need to make informed decisions about "awake/asleep".
Would like to write more, but got to go do another case. Contact AANA website for further info and links. Regards, Haldol
