[Pathogenic factors of convulsion in neonates with hypoxic-ischemic encephalopathy].

OBJECTIVE

To explore the pathogenic factors of convulsion in neonates with mild to severe hypoxic-ischemic encephalopathy.

METHODS

Altogether 70 neonates with mild to severe hypoxic-ischemic encephalopathy (HIE) were admitted into our hospital between Jan. 1988 and Jan. 2001. Serum calcium was dynamically monitored in all the patients, with cerebral ultrasonography performed.

RESULTS

Convulsions occurred within the first and second days after birth in the neonates of convulsion group, whose serum calcium levels were significantly decreased during the third to sixth days in comparison with those of non-convulsion group (P<0.01). Cerebral ultrasonography showed that 1 to 3 d after birth, cerebral edema occurred in all the neonates of convulsion group (n=39), with 30 of them having diffuse edema. Cerebral edema was gradually alleviated in the fourth to seventh day after birth. In non-convulsion group (n=31), 14 patients suffered diffuse cerebral edema within 2 d after birth, an incidence significantly lower than that in convulsion group. Intracranial hemorrhage took place in 23 neonates in convulsion group (58.97 %), and the incidence in non-convulsion group was only 38.7 %.

CONCLUSION

The principal causes of convulsions in neonates include hypoxia and cerebral edema, along with secondary causes such as birth trauma and hypocalcemia.