[Limits of pure analgesic anesthesia].

Before dealing with this subject, the author believes that it is useful to give a definition of this technique and justify it. He then recalls the results which he obtained with various analgesic drugs, few products permit this technique, either because of too low analgesic power, or because of the appearance in high dosage, of troublesome or dangerous side-effects. At present, in this type of anesthetic, one may use either morphine or fentanyl or fentathienyl. Analgesic anesthesia with morphine. This technique presents advantages and disadvantages. The author has no personal experience of high doses of morphine and can only report that of other authors who have studied this problem. Anesthesia analgesia with fentanyl and fentathienyl. The author believes that this technique presents advantages over the previous technique, he has personally studied the clinical pharmacology of high doses of fentanyl and he believes that this drug used by the intravenous route, at a dose of 0.05 mg/kg associated with a curare derivative, possesses favourable cardiovascular and respiratory metabolic effects during the surgical operation, but one must recognize that +/-20 p. 100 of cases, fentanyl associated only with curare is not sufficient to give a stable anesthetic. At present, the author has replaced, in his technique, fentanyl by fentathienyl which is a morphine derivative 6 to 7 times more powerful. He found with this drug most of the properties of high doses of fentanyl but the analgesia obtained is deeper, one does not find more than 20 p. 100 of resistant cases. However, the author noted the fairly frequent appearance of tachycardia for which there was no valid explanation. In conclusion. The author believes that in the reproaches which are made to analgesic anesthesia, some are justified, others are less so. It requires prolonged post-operative supervision, but the latter would be advisable for any other type of anesthesia. It dose not always permit one, in its pure form, to obtain stable anesthesia, but this is less and less true with the appearance of more and more powerful derivatives. The use of analgesic anesthesia as a routine technique is only possible in the form of sequential analgesic anesthesia, a technique which uses an antimorphine drug to awaken the patient. In this field, various new products are presented are discussed.