EFFECTS OF VARIATION IN UMBILICAL ARTERY FLOW ON FOETAL MIDDLE CEREBRAL ARTERY FLOW IN HYPERTENSIVE PREGNANCIES
Introduction: Cerebral vasodilation occurs in conditions of hypovolemia and cerebral hypoxia in adults. This effect is also found in foetuses. In gestational hypertension, blood flow to the foetus is compromised creating a situation somewhat similar to hypovolemia and cerebral hypoxia. Doppler ultrasound indices namely Resistive Index (RI) Pulsatility Index (PI) and Systolic-Diastolic Ratio (S/D)are useful tools in picking these changes in blood flow. The aim of this study was to see the effects of alterations in umbilical artery flow on foetal middle cerebral arterial flow with Doppler ultrasound parameter. Material and Methods: Ninety pregnant women with pregnancy-induced hypertension were selected with gestational age >35 weeks. Doppler ultrasound examination were carried out to record Pulsatility Index (PI), Resistive Index (RI), and Systolic-Diastolic Ratio (S/D) of Umbilical artery (UA) and Foetal Middle Cerebral Artery (MCA). Pearsonâ€™s correlation was determined between UA and MCA PI, RI and SD. Results: A non-significant (p=0.067) negligible negative correlation (r= -0.194) was seen between UA PI and MCA PI. A significant (p=0.000) very strong negative correlation (r= -0.754) was present between the UA RI and MCA RI. A significant (p=0.002) moderate negative correlation (r= -0.328) was observed between UA SD and MCA SD. Conclusion: A significant negative correlation was observed between the resistive indices and SD ratios of umbilical and middle cerebral arteries. No significant correlation was found between the pulsatility indices of the two arteries.
Pak J Physiol 2013;9(2):15â€“8
2. Pearce WJ. Mechanisms of hypoxic cerebral vasodilatation. Pharmacol Ther 1995;65(1):75â€“91.
3. Sutterlin MW, Seelbach-Gobel B, Oehler MK, Heupel M, Dietl J. Doppler ultrasonographic evidence of intrapartum brain-sparing effect in fetuses with low oxygen saturation according to pulse oximetry. Am J Obstet Gynecol 1999;181(1):216â€“20.
4. Dekker GA, Sibai BM. Etiology and pathogenesis of preeclampsia: current concepts. Am J Obstet Gynecol 1998;179(5):1359â€“75.
5. Naicker T, Khedun SM, Moodley J, Pijnenborg R. Quantitative analysis of trophoblast invasion in preeclampsia. Acta Obstet Gynecol Scand 2003;82(8):722â€“9.
6. Kaufmann P, Black S, Huppertz B. Endovascular trophoblast invasion: implications for the pathogenesis of intrauterine growth retardation and preeclampsia. Biol Reprod 2003;69(1):1â€“7.
7. Goldman-Wohl D, Yagel S. Regulation of trophoblast invasion: from normal implantation to pre-eclampsia. Mol Cell Endocrinol 2002;187(1â€“2):233â€“8.
8. Pijnenborg R, Bland JM, Robertson WB, Brosens I. Uteroplacental arterial changes related to interstitial trophoblast migration in early human pregnancy. Placenta 1983;4(4):397â€“413.
9. Bhatt C, Arora J, Shah M. Role of color doppler in pregnancy induced hypertension (a study of 100 cases). Indian J Radiol Imaging 2003;13:417â€“20.
10. Bolz N, Kalache KD, Proquitte H, Slowinski T, Hartung JP, Henrich W, et al. Value of Doppler sonography near term: can umbilical and uterine artery indices in low-risk pregnancies predict perinatal outcome? J Perinat Med 2013;41(2):165â€“70.
11. Torres PJ, Gratacos E, Alonso PL. Umbilical artery Doppler ultrasound predicts low birth weight and fetal death in hypertensive pregnancies. Acta Obstet Gynecol Scand 1995;74(5):352â€“5.
12. Dicke JM, Huettner P, Yan S, Odibo A, Kraus FT. Umbilical artery Doppler indices in small for gestational age fetuses: correlation with adverse outcomes and placental abnormalities. J Ultrasound Med 2009;28(12):1603â€“10.
13. Khalid M, Wahab S, Kumar V, Khalid S, Haroon S, Sabzposh NA. Doppler indices in prediction of fetal outcome in hypertensive pregnant women. Nepal J Obstet Gynaecol 2011;6(1):28â€“34.
14. Keats TE, Sistrom C. Atlas de medidas radiolÃ³gicas. 7th ed. Madrid, Spain: Elsevier Science; 2002.
15. Mosbyâ€™s Dictionary of Medicine, Nursing & Health Professions. 8th ed. St. Louis, Missouri: Elsevier Science Health Science Division; 2009.
16. Shahinaj R, Manoku N, Kroi E, Tasha I. The value of the middle cerebral to umbilical artery Doppler ratio in the prediction of neonatal outcome in patient with preeclampsia and gestational hypertension. J Prenat Med 2010;4(2):17â€“21.
17. Nanthakomon T, Somprasit C. The value of middle cerebral artery-umbilical artery pulsatility index ratio in prediction of severe fetal growth restriction. Thammasat Med J 2010;10(3):264â€“70.
18. Ebrashy A, Azmy O, Ibrahim M, Waly M, Edris A. Middle cerebral/umbilical artery resistance index ratio as sensitive parameter for fetal well-being and neonatal outcome in patients with preeclampsia: case-control study. Croat Med J 2005;46(5):821â€“5.
19. Makhseed M, Jirous J, Ahmed MA, Viswanathan DL. Middle cerebral artery to umbilical artery resistance index ratio in the prediction of neonatal outcome. Int J Gynaecol Obstet 2000;71(2):119â€“25.
20. Yalti S, Oral O, Gurbuz B, Ozden S, Atar F. Ratio of middle cerebral to umbilical artery blood velocity in preeclamptic & hypertensive women in the prediction of poor perinatal outcome. Indian J Med Res 2004;120(1):44â€“50.
Pakistan Journal of Physiology, Pak J Physiol, PJP is FREE for research and academic purposes. It can be downloaded and stored, printed, cited and quoted with full reference of, and acknowledgement to the PJP.