Enhancement of hepatic artery resistance to blood flow in preeclampsia in presence or absence of HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets)

OBJECTIVE Our purpose was to test the hypothesis that the HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome is the result of excessive vasoconstriction of the hepatic arterial circulation. STUDY DESIGN Doppler ultrasonography was used to measure the pulsatility index of the common hepatic artery in 14 women with preeclampsia, 15 with preeclampsia complicated by HELLP syndrome, and 8 with HELLP syndrome but without proteinuria. Gestational age ranged from 24 to 38 weeks. The study group was compared with a reference group (n = 42). RESULTS Both in preeclampsia and in the HELLP syndrome the hepatic artery pulsatility index values were significantly increased compared with the reference group. However, no significant differences were found between the preeclamptic group, the HELLP group with proteinuria, and those with HELLP without proteinuria. CONCLUSIONS These findings indicate that hepatic artery resistance to blood flow is increased in preeclampsia in the presence or absence of the HELLP syndrome. The results also demonstrate that vasoconstriction of the hepatic arteries is not more pronounced in the HELLP syndrome than in other manifestations of preeclampsia. Therefore factors other than vasoconstriction are likely to be responsible for the development of the HELLP syndrome.