Articles: general-anesthesia.
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Major traumatic injury frequently causes hemodynamic instability that necessitates reducing the usual dose of anesthetic given for surgery. Nevertheless, a lower dose may be sufficient to provide anesthesia because of conditions present in trauma victims that are known to reduce anesthetic requirement (hypotension, hypothermia, and acute alcohol intoxication). To determine the incidence and patient perception of recall of surgery, 51 patients were interviewed after surgery for major trauma. ⋯ Of the six patients in this group who recalled surgery (43%), two considered this awareness their worst hospital experience. No condition known to reduce anesthetic requirement did so reliably enough that recall of surgery did not occur when the anesthetic dose had to be reduced because of major trauma. The authors conclude that the incidence of recall of surgery in victims of major trauma is considerable, and that reducing the dose of anesthetic increases this incidence, despite the presence of conditions known to reduce anesthetic requirement.
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The requirements of anesthesia for laryngoscopy and microlaryngeal surgery must be compatible with maximum safety and minimum patient discomfort. Some techniques require the use of an endotracheal tube while some do not. ⋯ In general, for pediatric endoscopy we prefer spontaneous respiration with inhalational anesthesia supplemented by topical lignocaine (lidocaine), and in adults, a relaxant technique with controlled jet ventilation supplemented by topical lignocaine. A new pediatric microlaryngoscope and a new tube for jet ventilation in older children and adults are described.
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In order to evaluate the possible physiologic significance of intra- and postoperative hypotension, we monitored arterial blood pressure and heart rate continuously for 36 hr starting the night before and ending the morning after operation in 34 gynecologic patients. The lowest pressures that occurred during physiologic sleep were compared with the lowest arterial pressures that occurred during anesthesia without deliberate hypotension. ⋯ These physiologic nadirs in blood pressure are assumed to be tolerated well by the patient. Intraoperative pressures in elderly patients frequently drifted below sleep-associated levels of blood pressure and may, therefore, constitute physiologically significant hypotension.
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Comparative Study
Factors influencing the cholinesterases of cerebrospinal fluid in the anaesthetized cat.
Both acetylcholinesterase and non-specific cholinesterase are found in cerebrospinal fluid and blood plasma of the cat; the ratio of activities acetylcholinesterase/non-specific cholinesterase is about 1.5 in cerebrospinal fluid and 0.15 in plasma. A search was made for factors capable of influencing the concentration of the two cholinesterases in cerebrospinal fluid. Either the ventricular system was perfused with artificial cerebrospinal fluid from a lateral ventricle to the aqueduct, or the atlanto-occipital membrane was punctured and cerebrospinal fluid was collected continuously from the cisterna magna. ⋯ A rise in acetylcholinesterase concentration was obtained upon stimulation of the central ends of the sciatic nerves; this was inhibited by atropine but not by N-methylatropine, indicating that the rise was due to increased nervous activity and not to the circulatory effects of the stimulation, since the changes in blood pressure caused by the stimulation remained the same after atropine administration. Amphetamine or leptazol raised the levels of acetylcholinesterase but it was not possible to determine whether this was due only to increased central nervous activity, since there was invariably leakage through the blood-brain barrier which by itself would be sufficient to produce the effect. A rise in the level of acetylcholinesterase was seen after administration of pyrogen; this was apparently not a simple effect of warming the body, but due to the action of the pyrogen on centers concerned with temperature control, since warming the animal by external heat failed to produce a similar change.(ABSTRACT TRUNCATED AT 400 WORDS)
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A pregnant patient at 38 weeks gestation presented for a combined procedure of Caesarean section, tubal ligation and cerebral aneurysm clipping. Anaesthesia was induced with thiopental, succinylcholine was administered to facilitate tracheal intubation, and intravenous lidocaine and sodium nitroprusside were used to reduce the hypertensive response to tracheal intubation. ⋯ Following completion of the surgical procedures, the patient promptly emerged from anaesthesia and was neurologically normal in the operating room. It is concluded that general anaesthesia can be used satisfactorily for a combined procedure of Caesarean section and cerebral aneurysm clipping.