Augmented thermic effect of amino acids under general anaesthesia: a mechanism useful for prevention of anaesthesia-induced hypothermia.
Augmented thermic effect of amino acids under general anaesthesia: a mechanism useful for prevention of anaesthesia-induced hypothermia.
复制标题
全身麻醉下氨基酸的增强热效应：一种用于预防麻醉引起的体温过低的机制。
作者：
E. Selldén;T. Brundin;J. Wahren
1.静脉输注氨基酸刺激正常人的能量消耗和热量积累。为了找出这种刺激是否也发生在全身麻醉期间，对21名患者在麻醉前、麻醉中和手术后进行了产热测量。2.在整个麻醉过程中，10例患者接受了19种氨基酸(240kJ/h)的混合静脉输注。另11例患者作为对照组，接受生理盐水治疗。使用预先插入肺动脉和体动脉的导管，测量心输出量、动静脉氧分压差、肺摄氧量和混合血温。3.在麻醉和手术期间，对照组的血压下降了0.67+/-0.09℃/h，氨基酸治疗组下降了0.38+/-0.06℃/h。术前34+/-4min麻醉使对照组和氨基酸组的肺摄氧量分别降低145+/-9ml/min和81+/-10ml/min，总能量消耗分别减少47W和26W。差异为21W，说明了氨基酸的生热作用。这个值可以与未麻醉的人在相同的氨基酸输注30分钟后观察到的4W的值进行比较。4.麻醉后苏醒时，氨基酸组患者的氧耗量较麻醉前升高71+/-21%，且无颤抖，迅速恢复常温，而对照组患者尽管持续低温和剧烈颤抖，但氧耗量仍略低于麻醉前水平。(摘要截断250字)
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)