With refinement, the ECB technology is positioned to become an important therapeutic platform in restorative neurosurgery and, in combination with other therapeutic factors, may be relevant for the treatment of a variety of neurological disorders. Clinical trial registration no.: NCT01163825.

1. Intravenous infusion of amino acids stimulates energy expenditure and heat accumulation in normal man. To find out whether such stimulation also occurs during general anaesthesia, thermogenesis was measured in 21 patients before, during and after anaesthesia and surgery. 2. Ten patients received a mixture of 19 amino acids (240 kJ/h) infused intravenously throughout the anaesthesia. The other 11 patients, serving as controls, received saline. Using catheters previously inserted into the pulmonary and a systemic artery, cardiac output, arteriovenous oxygen difference, pulmonary oxygen uptake and mixed blood temperature were measured. 3. During anaesthesia and surgery, the blood temperature fell by 0.67 +/- 0.09 degrees C/h in the control patients and by 0.38 +/- 0.06 degrees C/h in the amino acid-treated patients. Anaesthesia during 34 +/- 4 min before surgery reduced the pulmonary oxygen uptake by 145 +/- 9 ml/min in the control patients and by 81 +/- 10 ml/min in the amino acid-treated patients, corresponding to reductions in total energy expenditure of 47 W in the control group and 26 W in the amino acid-treated group. The difference, 21 W, illustrates the thermogenic action of the amino acids. This value may be compared with that of 4 W, observed in unanaesthetized individuals subjected to 30 min of identical amino acid infusions. 4. At awakening after the anaesthesia, the oxygen consumption rose to 71 +/- 21% above the pre-anaesthesia level in the amino acid-treated patients, who, without shivering, rapidly returned to normothermia, whereas in the control patients the oxygen uptake remained slightly below the pre-anaesthesia level, despite sustained hypothermia and vigorous shivering.(ABSTRACT TRUNCATED AT 250 WORDS)

Intraoperative infusion of amino acids has been found to stimulate energy expenditure and thereby prevent anaesthesia-induced hypothermia. Rectal temperature and respiratory gas exchange were measured in 24 female patients before and after isoflurane anaesthesia. Sixteen patients had an amino acid mixture of 240 kJ h-1, infused over 1-2 h before anaesthesia and eight control patients received saline. We compared the results with data from six female volunteers treated with amino acids; they were not premedicated or anaesthetized. In lorazepam premedicated patients, amino acids increased the pre-anaesthesia temperature by 0.3 degrees C h-1, twice that observed in the volunteers. At awakening after anaesthesia, energy expenditure increased to 50-60% above baseline in the amino acid treated patients, while in the control patients, receiving saline, no increase occurred, despite vigorous shivering. Amino acid infusion prevented hypothermia by increasing heat accumulation and causing delayed stimulation of heat production. The heat accumulation response to amino acid infusion was increased after premedication with lorazepam.

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