Rogers A T, Prough D S, Stump D A, Gravlee G P, Angert K C, Roy R C, Mills S A, Hinshelwood L
Department of Anesthesia, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27103.
Anesth Analg. 1989 Feb;68(2):122-6. doi: 10.1213/00000539-198902000-00010.
Changes in cerebral blood flow (CBF) associated with decreases in mean arterial pressure (MAP) produced by sodium nitroprusside (SNP) infusion were measured by intra-aortic injection of 133Xe in 17 patients during hypothermic cardiopulmonary bypass (CPB). In each patient, CBF was determined at baseline and then again following SNP-induced reduction of MAP. Two groups were studied. In Group I (n = 9), PaCO2 was maintained near 42 mm Hg uncorrected for nasopharyngeal temperature (NPT). In Group II (n = 8), PaCO2 was maintained near 60 mm Hg, uncorrected for NPT. Nasopharyngeal temperature, MAP, pump oxygenator flow, PaO2, and hematocrit were maintained within a narrow range in each patient during both studies. Since the baseline CBF determinations were conducted at the higher MAP in all subjects, we corrected post-SNP CBF data for the spontaneous decline that occurs over time during CPB. In Group I, a reduction in MAP from 76 +/- 9 mm Hg (mean +/- SD) to 50 +/- 6 mm Hg was associated with a reduction in CBF from 17 +/- 5 to 13 +/- 3 ml.100 g.min-1 (P less than 0.01), a decrease that became statistically insignificant once the time correction factor had been applied (16 +/- 4 ml.100 g-1.min-1). In Group II, MAP declined from 75 +/- 5 mm Hg to 54 +/- 5 mm Hg, and CBF declined from 25 +/- 10 to 17 +/- 7 ml.100 g.min-1 (P less than 0.01), but, again, after time correction, the CBF decline was statistically insignificant (22 +/- 8 ml.100 g-1.min-1).(ABSTRACT TRUNCATED AT 250 WORDS)
在17例低温体外循环（CPB）患者中，通过主动脉内注射133Xe测量硝普钠（SNP）输注导致平均动脉压（MAP）降低时脑血流量（CBF）的变化。在每位患者中，先在基线时测定CBF，然后在SNP诱导MAP降低后再次测定。研究分为两组。第一组（n = 9），未根据鼻咽温度（NPT）校正时，将动脉血二氧化碳分压（PaCO2）维持在42 mmHg左右。第二组（n = 8），未根据NPT校正时，将PaCO2维持在60 mmHg左右。在两项研究中，每位患者的鼻咽温度、MAP、血泵氧合器流量、动脉血氧分压（PaO2）和血细胞比容均维持在狭窄范围内。由于所有受试者的基线CBF测定均在较高的MAP下进行，因此我们对CPB期间随时间自然下降的SNP注射后CBF数据进行了校正。在第一组中，MAP从76±9 mmHg（平均值±标准差）降至50±6 mmHg，同时CBF从17±5降至13±3 ml·100 g-1·min-1（P<0.01），应用时间校正因子后，这种降低变得无统计学意义（16±4 ml·100 g-1·min-1）。在第二组中，MAP从75±5 mmHg降至54±5 mmHg，CBF从25±10降至17±7 ml·100 g-1·min-1（P<0.01），但同样，时间校正后，CBF的下降无统计学意义（22±8 ml·100 g-1·min-1）。（摘要截短于250字）
