Anesthesia definition

Russia remains secretive about this operation. Reporters learned that they drilled holes in the floor and used vents high on the wall to pump gas into the theater. Regrettably, however, they were unable to learn the precise nature of the gas, beyond the admission by a Russian scientist that it was a derivative of Fentanyl. Several highly potent drugs fit that definition, including carfentanil, sufentanil, alfentanil, remifentanil and etorphine. Any of these can produce anesthesia, lasting from minutes to hours. A Russian medical authority later added that they used 5x the effective dose in order to guarantee a rapid effect on the terrorists. It is not clear exactly what this means. 

In regional anesthesia (spinal anesthesia) with a local anesthetic (p. 204), nociception is eliminated, while consciousness is preserved. This procedure, therefore, does not fall under the definition of general anesthesia... 

In experimental animals the effect of ephedrine administered intravenously is similar to that of epinephrine. The arterial pressure — systolic, diastolic, and mean pressure — rises and vagal slowing occurs. Compared with epinephrine, the pressor response to ephedrine occurs somewhat more slowly and lasts about ten times longer. Furthermore, it requires more ephedrine than epinephrine to obtain an equivalent pressor response. How much more depends on the species tested, type and degree of anesthesia, dose level, and individual variability of the test animal. It is, therefore, almost impossible to give a definite figure for the relative potency of ephedrine and epinephrine. It is commonly accepted that it requires about 250 times more ephedrine than epinephrine to achieve equipressor responses. 

Several small clinical trials have suggested that total intravenous anesthesia with propofol reduces the incidence of postoperative nausea and vomiting and results in shorter emergence times. However, a systematic review (52) and a meta-analysis (53) have shown that most studies were small, did not have follow-up for more than 6 hours postoperatively, and were sponsored by industry. The results were difficult to combine, owing to heterogeneous definitions of postoperative nausea and vomiting. 

Systemic effects, such as dizziness, tachycardia, agitation, nausea, tremor, syncope, seizures, and bronchos-pasm, are a definite risk with local anesthesia in a vascular area. A wide range of patients present for dental surgery, and it is important that an adequate medical history be taken and accurate doses calculated on an individual basis. Low concentrations of adrenahne should be used. 

In a careful meta-analysis, 29 randomized, controlled studies of the incidence of transient radicular irritation were identified (243). Lidocaine and mepivacaine were identified as the two local anesthetics that most commonly cause transient radicular irritation, while prilo-caine, bupivacaine, and ropivacaine had the lowest incidences. Owing to insufficient data, definitive statements could not be made about the effects of the baricity of the local anesthetic, the concentration, and the effect of vasoconstrictors, although all these factors seemed not to be relevant. With regard to intrathecal ropivacaine, the incidence in the formal studies was zero. However, there has been one previous report after intrathecal administration, and one report of transient radicular irritation following epidural anesthesia with ropivacaine the symptoms resolved within 24 hours (244). 

Jaundice after general anesthesia in which nitrous oxide was the only anesthetic has been described (36). However, contamination with halothane was not definitely ruled out. 

Easton, J.D., et al., Definition and evaluation of transient ischemic attack a scientific statement for healthcare professionals from the American Heart Association/American Stroke Association Stroke Council Council on Cardiovascular Surgery and Anesthesia Councilon Cardiovascular Radiology and Intervention Council on Cardiovascular Nursing and the Interdisciplinary Council on Peripheral Vascular Disease. The American Academy of Neurology affirms the value of this statement as an educational tool for neurologists. Stroke, 2009.40(6) p. 2276-93. 

Wandelt, M.A. Definitions of words germane to evaluation of healthcare. NLNPub 1976(15-1611) 57-58,1976. Warner, M.A. (eds.). Positioning in Anesthesia and Surgery. Philadelphia, PA WB. 

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