Comparison of the effects of phenylephrine and norepinephrine on tissue oxygen metabolism in elderly patients undergoing fluid restriction / 中国医师进修杂志

ABSTRACT

Objective To investigate the effects of phenylephrine and norepinephrine on tissue oxygen metabolism in elderly patients undergoing fluid restriction. Methods Eighty elderly patients who had underwent elective colorectal surgery were selected, with ASA of Ⅰ-Ⅱ grade. The patients were divided into restricted fluid administration combined with phenylephrine group (group Ⅰ) and restricted fluid administration combined with norepinephrine group (groupⅡ) by random digits table with 40 cases each. The compound recipe sodium lactate was given at a rate of 5 ml/(kg · h). Small dose of phenylephrine was infused intravenously at 0.1-0.3μg/(kg · min) simultaneously during the surgery in group Ⅰ, or norepinephrine 0.01-0.03 μg/(kg · min) in group Ⅱ. Mean arterial pressure (MAP) was maintained ≥ 65 mmHg (1 mmHg = 0.133 kPa). The intraoperative blood loss was replaced with the equal volume of 6% hydroxyethyl starch 130/0.4. The blood gas analysis, hemoglobin and so on were determined before the surgery (T0), 1 h after beginning of surgery (T1), 2 h after beginning of surgery (T2) and at the time of leaving operation room (T3). The complications were recorded. Results There were no statistical differences in MAP, central venous pressure (CVP), heart rate, lactic acid, arterial partial pressure of oxygen, central venous oxygen pressure, central venous blood oxygen saturation, oxygen uptake rate, hemoglobin, albumin, blood urea nitrogen, creatinine and incidence of complication between 2 groups (P>0.05). The T1-3 hemoglobin and arterial oxygen content (CaO2), T1 and T3 venous oxygen content (CcvO2) and T2 atrerial venous oxygen content differences (Da-cvO2) in groupⅠwere significantly higher than those in groupⅡ, hemoglobin(103.8 ± 7.9) g/L vs. (110.8 ± 8.6) g/L, (101.7 ± 7.7) g/L vs. (107.3 ± 7.8) g/L and (101.6 ± 6.9) g/L vs. (106.8 ± 5.6) g/L; CaO2 (140.6 ± 9.7) mmol/L vs. (149.6 ± 10.5) mmol/L, (137.5 ± 9.3) mmol/L vs. (144.9 ± 10.2) mmol/L and (137.2 ± 9.2) mmol/L vs. (143.1 ± 8.9) mmol/L;CcvO2(119.8 ± 10.2) mmol/L vs. (126.4 ± 10.8) mmol/L and (102.3 ± 8.6) mmol/L vs. (108.5 ± 8.9) mmol/L;Da-cvO2(19.6 ± 3.9) mmol/L vs. (23.0 ± 4.5) mmol/L, and there were statistical differences (P<0.05). Conclusions Phenylephrine has more effect on tissue oxygen metabolism in the elderly patients undergoing fluid-restricted abdominal surgery.