SUMMARYRats were anesthetized with ether, Pentothal, or cyclopropane and then given irreversible traumatic shock. The same 3 anesthetics were administered after the shock to furnish adequate surgical anesthesia. Comparison of survival times indicated that the animals receiving Pentothal or cyclopropane lived longer than those that had received ether.Additional rats were anesthetized with ether or cyclopropane and then cooled to produce hypothermic anesthesia for traumatization. During cooling, the volatile agent was eliminated. After the trauma, ether, Pentothal, or cyclopropane was administered so that the animals had adequate surgical anesthesia. Comparison of survival times showed that the animals receiving ether did not live as long as those who had received cyclopropane or Pentothal after the trauma. In this series, the animals receiving ether had a significantly shorter survival time than did the controls that received no agent following trauma.