Igari T, Hoshino S, Iwaya F, Ando S
Department of Cardiovascular Surgery, Fukushima Medical College, Fukushima City, Japan.
Cardiovasc Surg. 1999 Jan;7(1):106-11. doi: 10.1016/s0967-2109(98)00092-1.
Cerebral blood flow was measured using transcranial doppler during cardiopulmonary bypass in nine patients with selective cerebral perfusion for surgery of arch aorta (group S). For comparison, 11 adult open heart patients (group C) were also measured. The authors' selective cerebral perfusion at 28 degrees C resulted in moderate hypothermia and antegrade perfusion using independent pumps for three branches. Total flow in the three branches was 500 ml/min. A Labodop DP-100 doppler ultrasound velocimeter was used to measure middle cerebral arterial blood flow velocity. Hemoglobin concentration and oxygen saturation were also measured in arterial and jugular venous blood. The arteriovenous oxygen content difference (Ca-vO2) was calculated and multiplied by the middle cerebral arterial blood flow velocity value, which resulted in the cerebral metabolic rate for oxygen (CMRO2). The cerebral perfusion pressure of group S was lower than in group C, and the arterial carbon-dioxide tension (PaCO2) of group S was higher than in group C during cardiopulmonary bypass. Middle cerebral arterial blood flow velocity values of both groups remained constant before, during and after cardiopulmonary bypass. The CMRO2 decreased during cardiopulmonary bypass and showed no difference between the two groups. The changes in PaCO2 might be significant factors in the increase in cerebral blood flow during selective cerebral perfusion. This study supports the conclusion that, compared with our routine open heart surgery procedures, our selective cerebral perfusion procedures had the same cerebral blood flow and oxygen metabolism during cardiopulmonary bypass.
在9例接受主动脉弓手术并采用选择性脑灌注的患者（S组）体外循环期间，使用经颅多普勒测量脑血流量。为作比较，还对11例成人心脏直视手术患者（C组）进行了测量。作者在28℃下进行的选择性脑灌注导致中度低温，并使用独立泵对三个分支进行顺行灌注。三个分支的总流量为500毫升/分钟。使用Labodop DP - 100多普勒超声测速仪测量大脑中动脉血流速度。还测量了动脉血和颈静脉血中的血红蛋白浓度和血氧饱和度。计算动静脉氧含量差（Ca - vO2），并将其乘以大脑中动脉血流速度值，得出脑氧代谢率（CMRO2）。S组的脑灌注压低于C组，体外循环期间S组的动脉二氧化碳分压（PaCO2）高于C组。两组的大脑中动脉血流速度值在体外循环前、期间和之后均保持恒定。体外循环期间CMRO2降低，两组之间无差异。PaCO2的变化可能是选择性脑灌注期间脑血流量增加的重要因素。本研究支持以下结论：与我们常规的心脏直视手术程序相比，我们的选择性脑灌注程序在体外循环期间具有相同的脑血流量和氧代谢。
