Malagon I, Hogenbirk K, van Pelt J, Hazekamp M G, Bovill J G
Department of Anaesthesia, Leiden University Medical Centre, Albinusdreef 2, PO Box 9600, 2300 RC Leiden, The Netherlands.
Br J Anaesth. 2005 Jun;94(6):805-9. doi: 10.1093/bja/aei142. Epub 2005 Apr 15.
Paediatric cardiac surgery is associated with some degree of myocardial injury. Ischaemic preconditioning (IP) has been investigated widely in the adult population. Volatile agents have been shown to simulate IP providing extra protection to the myocardium during adult cardiopulmonary bypass (CPB) while propofol seems to act through different mechanisms. IP has not been investigated in the paediatric population to the same extent. Cardiac troponin T (cTnT) is a reliable marker of myocardial injury in neonates and children. We have investigated the relationship between three anaesthetic agents, midazolam, propofol, and sevoflurane, and postoperative production of cTnT.
Ninety patients undergoing repair of congenital heart defect with CPB were investigated in a prospective randomized study. cTnT was measured four times during the first 24 h following admission to the paediatric intensive care unit. Other variables measured included arterial blood gases, lactate, fluid balance, use of inotropic drugs, PaO2/FiO2 ratio and ventilator hours.
cTnT was elevated in all three groups throughout the study period. The differences between the three groups were not statistically significant. Eight hours after admission to the intensive care unit cTnT concentrations tended to be higher in the midazolam group [mean (95% confidence intervals)]; 2.7 (1.9-3.5) ng ml(-1). Patients receiving a propofol-based anaesthesia had similar concentrations 2.6 (1.7-3.5) ng ml(-1) while those receiving sevoflurane tended to have a lower cTnT production 1.7 (1.3-2.2) ng ml(-1).
Midazolam, propofol, and sevoflurane appear to provide equal myocardial protection in paediatric cardiac surgery when using cTnT as a marker of myocardial damage.
小儿心脏手术会伴有一定程度的心肌损伤。缺血预处理（IP）已在成年人群中得到广泛研究。挥发性麻醉剂已被证明可模拟缺血预处理，在成人心脏体外循环（CPB）期间为心肌提供额外保护，而丙泊酚似乎通过不同机制发挥作用。缺血预处理在小儿人群中的研究程度尚不及成人。心肌肌钙蛋白T（cTnT）是新生儿和儿童心肌损伤的可靠标志物。我们研究了三种麻醉剂咪达唑仑、丙泊酚和七氟醚与术后cTnT产生之间的关系。
在一项前瞻性随机研究中，对90例接受CPB下先天性心脏病修复术的患者进行了调查。在入住小儿重症监护病房后的头24小时内，对cTnT进行了4次测量。测量的其他变量包括动脉血气、乳酸、液体平衡、血管活性药物的使用、PaO2/FiO2比值和机械通气时间。
在整个研究期间，三组患者的cTnT均升高。三组之间的差异无统计学意义。入住重症监护病房8小时后，咪达唑仑组的cTnT浓度往往较高[平均值（95%置信区间）]；为2.7（1.9 - 3.5）ng/ml。接受丙泊酚麻醉的患者浓度相似，为2.6（1.7 - 3.5）ng/ml，而接受七氟醚麻醉的患者cTnT产生量往往较低，为1.7（1.3 - 2.2）ng/ml。
当使用cTnT作为心肌损伤标志物时，咪达唑仑、丙泊酚和七氟醚在小儿心脏手术中似乎能提供同等的心肌保护。
