目的　探讨内源性一氧化碳 (CO)在新生儿缺氧缺血性脑病 (HIE)中的作用。方法　 32例HIE新生儿 (轻度 10例 ,中度 16例 ,重度 6例 )于急性期 (3d内 )及恢复期 (生后第 10天 )检测血浆CO水平 ,生后 5～ 7d进行颅脑CT扫描检查确定脑损害程度。观察血浆CO在急性期、恢复期的动态变化及与病情、脑损害程度的关系。 30例正常新生儿为对照组。结果　HIE新生儿轻、中、重度组急性期血浆CO水平分别为 (1.34± 0 .88)mg/L ,(1.6 8± 1.2 5 )mg/L ,(2 .79± 0 .96 )mg/L ,对照组为 (1.16± 0 .82 )mg/L。除轻度组外 ,中、重度组明显高于对照组 (P <0 .0 5或 0 .0 1) ,重度组明显高于轻、中度组 (P <0 .0 1或 0 .0 5 ) ,CO水平随脑损害程度加重而增高 ;恢复期轻、中、重度组血浆CO水平均降至正常 ,与对照组比较 ,差异无显著意义 (P >0 .0 5 )。结论　血浆CO水平与HIE病情及脑损害严重程度密切相关 ,CO可能在新生儿HIE的发病过程中具有重要意义。 Objective To investigate the role of endogenous carbon monoxide (CO) in neonatal hypoxic-ischemic encephalopathy (HIE). Methods Thirty-two HIE neonates (mild 10, moderate 16, severe 6) were enrolled in this study. Plasma CO levels were measured in the acute phase (3d) and convalescence (10 days after birth) Brain CT scan to determine the extent of brain damage. To observe the dynamic change of plasma CO in acute phase and convalescent phase and its relationship with the severity of disease and brain damage. 30 cases of normal newborn as control group. Results The levels of plasma CO in acute, moderate and severe neonatal HIE groups were (1.34 ± 0.88) mg / L, (1.6 8 ± 1.2 5) mg / L and (2.79 ± 0.96) mg / L, the control group was (1.16 ± 0.82) mg / L. Except the mild group, the moderate and severe groups were significantly higher than the control group (P <0.05 or 0.01), the severe group was significantly higher than the mild and moderate groups (P <0. 01 or 0 .0 5). The levels of CO increased with the severity of brain damage. The levels of plasma CO in the mild, moderate and severe recovery groups were all lower than those in the control group. There was no significant difference between the two groups (P> 0.05). Conclusions Plasma CO levels are closely related to the severity of HIE and brain damage. CO may play an important role in the pathogenesis of neonatal HIE.