London SUMMARY

Twenty-five patients were anaesthetized with chloroform. In 2 instances a partial rebreathing method using nitrous oxide and oxygen as the carrier gases was used. In 6 patients a non-rebreathing technique with oxygen alone as the carrier gas was substituted; the inspired concentration varied between 1.5 and 2.5 per cent. In the remainder a closed circle system was used giving inspired concentrations of up to 4 per cent. Cardiac irregularities were seen in 7 patients before recovery of consciousness. Hypotension below 90 mm Hg occurred in 3 patients. Of 26 cardiac output determina-tions in 8 patients 18 fell within the range 5 to 7 l./min. A four- to tenfold increase in finger blood flow was observed as well as a less marked increase in forearm blood:flow. In 87 determinations of arterial carbon dioxide tension in 18 patients 38 per cent were less than 40 mm Hg and only 20 per cent were above 60 mm Hg. Metabolic acidosis was observed in only 3 of 18 patients investigated. In the closed circle system oxygen consumption in 9 patients ranged from 159 to 261 ml/min. Blood chloroform levels derived from 29 samples from 7 patients gave a mean value of 17.9±4.7 mg per cent. The observation that there was no significan