Chan K H, Dearden N M, Miller J D, Andrews P J, Midgley S
Department of Clinical Neurosciences, University of Edinburgh, Western General Hospital, Scotland, United Kingdom.
Neurosurgery. 1993 Apr;32(4):547-52; discussion 552-3. doi: 10.1227/00006123-199304000-00009.
Transcranial doppler measurements of blood flow velocity in the middle cerebral artery were made during treatment of raised intracranial pressure (ICP) in 22 patients with severe brain injury. Twenty patients also had continuous measurement of arterial and jugular bulb venous oxygen saturation (SJO2). The transcranial Doppler parameters studied included both mean flow velocity and pulsatility index (PI). Successful treatment was defined as a reduction of ICP to less than 20 mm Hg with improvement or preservation of cerebral perfusion pressure (CPP) above 60 mm Hg. Successful therapy was associated with a significant rise in SJO2 and reduction of cerebral arteriovenous oxygen content difference (AVDO2) and PI only when the pretreatment CPP was less than 60 mm Hg. An increase in CPP beyond 70 mm Hg did not further improve cerebral oxygen delivery and PI, suggesting that autoregulation became a factor above this CPP threshold. Treatment failure during administration of hypnotic drugs resulted in a reduction in arterial pressure, CPP, SJO2, and mean velocity and in an increase in PI and AVDO2, despite a decrease in ICP. CPP is the most important parameter to monitor during ICP therapy. It should be maintained above 70 mm Hg in patients with severe brain injury.
在22例重型脑损伤患者颅内压（ICP）升高的治疗过程中，对大脑中动脉的血流速度进行了经颅多普勒测量。20例患者还连续测量了动脉血氧饱和度（SJO2）和颈静脉球部静脉血氧饱和度。所研究的经颅多普勒参数包括平均血流速度和搏动指数（PI）。成功治疗的定义为ICP降至20 mmHg以下，且脑灌注压（CPP）改善或维持在60 mmHg以上。仅当治疗前CPP小于60 mmHg时，成功治疗才与SJO2显著升高、脑动静脉氧含量差（AVDO2）和PI降低相关。CPP超过70 mmHg时，脑氧输送和PI并未进一步改善，这表明在此CPP阈值以上，自动调节成为一个影响因素。尽管ICP降低，但在给予催眠药物治疗期间治疗失败导致动脉压、CPP、SJO2和平均速度降低，PI和AVDO2升高。CPP是ICP治疗期间要监测的最重要参数。对于重型脑损伤患者，应将其维持在70 mmHg以上。
