Thermogenic effect of amino acids not demonstrated in heart surgery with cardiopulmonary bypass

Abstract

The lack of a thermal effect of the amino acids in the heart surgery was most probably due to the temperature gradients between the different body compartments, and also may have been due to the use of beta-blockers.

Activation of a Neutrophil-Derived Inflammatory Response in the Airways During Cardiopulmonary Bypass

“…This observation is consistent with previous studies showing that amino acids promote normothermia during general surgery (9), although not during cardiopulmonary bypass (12). This observation is consistent with previous studies showing that amino acids promote normothermia during general surgery (9), although not during cardiopulmonary bypass (12).…”

“…In the present study we prospectively determined the effect of amino acid infusion on esophageal core temperature and postoperative outcomes during off-pump coronary artery bypass grafting (CABG). Furthermore, intensive care unit stay [20 (19.5-38.4) vs 44 h; P ϭ 0.001] and days until fit for discharge from hospital [10 (9 -11) vs 12 (11)(12)(13) days; P ϭ 0.004] were significantly shorter in patients given amino acid. The esophageal core temperature at the end of surgery was 35.6 (35.3-35.8)°C [mean (95% confidence interval)] in the saline infusion group and 36.1°C (35.9 -36.3)°C in the amino acid infusion group (P ϭ 0.01).…”

“…We (10) reported that the core temperature increase in response to amino acid infusion in volunteers results from the combined effect of thermogenesis and an increase in the vasoconstriction threshold. Consequently, core temperatures in patients undergoing noncardiac surgery given amino acids are generally ϳ0.5°C more than those in patients given control fluids (9,11), although not during cardiopulmonary bypass (12). Sellden et al (13) also reported that amino acid infusions shorten the duration of postoperative hospitalization after abdominal surgery.…”

The effect of amino-acid infusion during off-pump coronary arterial bypass surgery on thermogenic and hormonal regulation

“…The temperature of pulmonary arterial blood, measured with a thermistor equipped with a pulmonary artery catheter (OptiQ; Hospira, Donegal, Ireland), was considered to be the core body temperature [14]. Cardiac output was measured using a thermodilution technique, and oxygen uptake was calculated as the product of the measured arterio-venous oxygen difference.…”