Reappraisal of Ether-Air Anesthesia / 대한마취과학회지

ABSTRACT

Air can be used as a carrier for volatile agent, ether, with a clear airway, normal pulmonary function and normal oxygenation. In 1858 John Snow, the Father of British Anesthesia stated in his book on Chloroform and Other Anesthetics that he believed it to be almost impossible for death to occur from ether administered with ordinary intelligence and attention. Today ether is probably still the safest anesthetic drug we possess. Ether is cheap and easily obtained; with controlled respiration 3% is adequate. Recovery smooth and rapid. Vomiting may be no different from other agents. Most machines depend upon cylinders of oxygen and other gases, and there are difficulties of refilling cylinders and the cost of transporting them. In such circumstances the E.M.O. Inhaler, allowing ether to be vaporized in known concentrations in air, has many advantages as an alternative to the open method administration. From all types of patients chosen at random 22 patients were studied for ether-air anesthesia. Anesthesia was induced with intravenous thiopental and subsequent endotracheal intubation was performed within 30 seconds with the aid of intravenous succinylcholine. SatO2, PaO2, pH, and Base E. were measured 3 times during pre-anesthesia, immediately after the intubation, and post-operatively by Radiometer, using the oxy-hemoglobin dissociation curve and the Siggard-Anderson alignment nomogram. Vital signs were recorded every 5 minutes. It is the purpose of this paper to present this series of 22 anesthetics by the use of the E.M.O. Inhaler with air and to discuss the possibility of hypoxia, advantages and limitations that became apparent. The results obtained may be summarized as follows. 1. It is essential that endotracheal intubation by carried out rapidly and that everything necessary be ready and immediately at hand before starting the anesthetic. 2. In all patients ventilated room air during anesthetic induction, no significant decreases of PaO2 and SatO2 were observed immediately after the endotracheal intubation. 3. The duration of any period of complete apnea inflicted on the patient must be carefully controlled. 4. 100% oxygen prevented the possibility of hypoxia on extubation after all the reflexes had returned. 5. Ether-air anesthesia is recommended without hesitation for use where economy and portability of anesthetic machine are needed.