Clinical significance of transcranial Doppler and end-tidal carbon dioxide partial pressure on cerebrovascular reserve capacity in cerebral vessels stenosis patients / 中国医师进修杂志

ABSTRACT

Objective To study the clinical significance of cerebrovascular reserve (CVR) capacity in cerebral vessels stenosis (CVS) patients with transcranial Doppler (TCD) and end-tidal carbon dioxide partial pressure (PETCO2).Methods Fifty-two CVS patients were divided into two groupsone blood vessel stenosis group (22 cases) and multi blood vessels stenosis group (30 cases).Forty-five normal persons were selected as control group.All the groups were routinely examined with TCD and PETCO2.Hypercapnia was induced by inhaling the carbon dioxide who breathed himself,and hypocapnia was induced by voluntary hyperventilation to investigate the CVR capacity.Results (1)The vasodilator reserve of affected side of one blood vessel stenosis group [(3.16 ± 2.73)％/mm Hg,1 mm Hg =0.133 kPa],the heavier side of multi blood vessels stenosis group [(2.41 ± 1.25)％/mm Hg],and control group [(3.75 ± 1.77)％/mm Hg] had significant difference (F =3.866,P ＜ 0.05).The vasodilator reserve of heavier side of multi blood vessels stenosis group was significantly lower than that of control group (t =-2.657,P ＜ 0.05).The overall reserve of affected side of one blood vessel stenosis group [(3.13 ± 1.38)％/mm Hg],the heavier side of multi blood vessels stenosis group [(2.01 ± 1.89)％/mm Hg],and control group [(3.51 ±0.92)％/mm Hg] had significant difference (F =5.905,P ＜ 0.05).The overall reserve of heavier side of multi blood vesse stenosis group was significantly lower than that of control group and affected side of one blood vessels stenosis group (t =-3.468,2.582,P ＜ 0.05).(2) There was no significant difference among the 3 groups in PETCO2 when eupnea,hypocapnia and hypercapnia.(3) The extent of vascular disease correlated negatively with the vasodilator reserve and overall reserve (r =-0.433 and-0.475,P＜0.05).Conclusions TCD and PETCO2 are simple,economic and effective methods for assessing CVR capacity.The CVR capacity is reduced in patients with cerebral vessels changes.