Alteration of skin laser-Doppler flux response to local cooling in gestational hypertension

Abstract

Purpose: The pathophysiology of the pregnancy-induced hypertension is still poorly understood, especially with regard to the central autonomic nervous system control and peripheral vascular factors.

Methods: Our study therefore aimed to investigate simultaneously the responses of blood pressure, heart rate, heart rate variability (HRV), and laser-Doppler (LD) flux to local cooling in healthy non-pregnant women (N = 12), in pregnant women with normal pregnancy (N = 16) and in women with gestational hypertension (N = 10).

Results: The direct and indirect LD flux responses to local cold exposure were diminished in normotensive pregnant females (Dunnett's test, p < 0.05) when compared to non-pregnant females with normal menstrual cycle, but not in females with pregnancy-induced hypertension. In addition, blood pressure increased and heart rate decreased during cold exposure only in normotensive pregnant females, but not in pregnant hypertensive females (paired t test, p < 0.05). Simultaneously calculated heart rate variability total power of HRV and LF power values typically increased during local cold provocation test in non-pregnant females and in normotensive pregnant females (paired t test, p < 0.05). In hypertensive pregnant females HRV indices remained unchanged.

Conclusion: Our results indicate that the cardiovascular reactivity adaptation seen in normal pregnancy is absent in gestational hypertension.