Pilato M A, Bissonnette B, Lerman J
Department of Anaesthesia, Hospital for Sick Children, University of Toronto, Ontario, Canada.
Can J Anaesth. 1991 Jan;38(1):37-42. doi: 10.1007/BF03009161.
To determine the effect of carbon dioxide on the cerebral circulation in anaesthetized infants and children, 13 healthy children, ASA physical status I or II, between three months and seven years of age and scheduled for urologic surgery, were studied. Anaesthesia was induced with thiopentone and vecuronium. After tracheal intubation, anaesthesia was maintained with 70 per cent nitrous oxide in oxygen, fentanyl 2 micrograms.kg-1, vecuronium 0.05 mg.kg-1 and 0.8-1.0 per cent end-tidal isoflurane. A caudal block was performed before surgery. Systolic arterial pressure, heart rate, oxygen saturation, temperature, and end-tidal isoflurane were maintained constant. Ventilation was adjusted to achieve an end-tidal PCO2 (PETCO2) of 20 mmHg. The PETCO2 was then randomly adjusted between 20 and 80 mmHg by the addition of carbon dioxide from an exogenous source. Cerebral blood flow velocity increased logarithmically and directly with the PETCO2 (r2 = 0.56). There were no complications associated with the use of transcranial Doppler sonography. These data indicate that CO2 has a direct effect on the velocity of blood in the middle cerebral artery in infants and children anaesthetized with isoflurane.
为了确定二氧化碳对麻醉状态下婴幼儿脑循环的影响，我们对13名健康儿童进行了研究，这些儿童年龄在3个月至7岁之间，ASA身体状况为I或II级，计划接受泌尿外科手术。采用硫喷妥钠和维库溴铵诱导麻醉。气管插管后，用70%氧化亚氮-氧气、2微克/千克芬太尼、0.05毫克/千克维库溴铵和0.8 - 1.0%的呼气末异氟烷维持麻醉。手术前进行骶管阻滞。维持收缩压、心率、血氧饱和度、体温和呼气末异氟烷浓度恒定。调整通气使呼气末二氧化碳分压（PETCO2）达到20 mmHg。然后通过从外源添加二氧化碳将PETCO2随机调整在20至80 mmHg之间。脑血流速度随PETCO2呈对数关系且直接增加（r2 = 0.56）。使用经颅多普勒超声检查未出现并发症。这些数据表明，二氧化碳对异氟烷麻醉的婴幼儿大脑中动脉的血流速度有直接影响。
