Circadian rhythm of plasma atrial natriuretic peptide, aldosterone, and blood pressure during the third trimester in normal and preeclamptic pregnancies

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Citations from the Literature

Cost-effectiveness of prenatat screening and immunization for hepatitis B virus Arevalo JA; Washington AE Department of Family Practice, University of Cal~onaia at Davis, Medical Center, Sacramento, CA 95817, USA J. AM. MED. ASSOC.; 259/3 (36%369)/1988/ Perinatal transmission of hepatitis B virus is associated with substantial morbidity and mortality, yet controversy still exists regarding the value of routine screening of pregnant women in the United States and subsequent immunization of their at-risk neonates. To evaluate the cost-effectiveness of such a screening and immunixation program, we developed a decision analysis model and obtained data from published reports, chart review, and a Delphi survey to determine outcome probabilities and costs. When considering direct and indirect costs, routine screening and immunization would be cost-effective at a prevalence of 0.06%, significantly lower than the national prevalence of 0.2%. At an annual national birth rate of 3.5 million births, a national policy of routine screening of all pregnant women would result in an annual net savings of more than $105 million. In the high-risk groups, as many as 140 cases of acute neonatal hepatitis and as many as 1400 cases of chronic liver disease would be prevented yearly per 1tltlOOO pregnant women screened, at a net annual savings of as much as $765 million.

PERINATOLOGY The cootiouous measurement of traoscutaoeous carbon dioxide tension (TcPCOsub 2), an atraumatic tool to verify fetal addosis?

Schmidt SCH; Saling EZ Department of Obstetrics, Women’s Hospital, D-loo0 Berlin 44, FRG BR. J. OBSTET. GYNAECOL.; 94/10(963+X6)/1987/ TcPCO, monitoring of the fetus during labour was evaluated as an atraumatic tool to identify or exclude fetal acidosis in 224 high-risk deliveries. A heated electrochemical sensor with a measuring temperature of 39C (n = 105) or 44C (n = 119) was applied to the fetal scalp. There was a statistically significant correlation between the TcPCO, and the fetal blood pH at both temperatures. The sensitivity of the method was 0.90 and 0.61 at the two measuring temperatures of 44degr. or 39degr. respectively and the specificity was 0.93 and 0.79 respectively. The negative predictive value was high (0.99 and 0.95 respectively), but the respective positive predictive values were only 0.53 and 0.24. We conclude that the continuous measurement of the TcPCO, is a valid additional tool to exclude fetal acidosis in most cases where fetal distress is indicated by the heart rate pattern but a TcPCO, value above the cut-off point should be verified by an additional method to avoid unnecessary operative deliveries. Circadian rhythm of plasma atrial natriuretic peptide, aldosterone, nod blood pressure during the third trimester in normal and precdamptic pregnancies Miyamoto S; Shimokawa H; Sumioki H; et al Department of Gynecology and Obstetrics, Faculty of MediInt J Gynecot Obstet 27

tine, Kyushu University, Higashi-ku, Fukuoka 812, Japan AM. J. OBSTET. GYNECOL.; 158/2 (393-399)/1988/ The influence of pregnancy on circadian variations of plasma atrial natriuretic peptide and aldosterone was studied. In those women with normal pregnancies, the mean 24-hour values of atrial natriuretic peptide and aldosterone increased, compared with the levels in normal nonpregnant subjects. In cases of severe preeclampsia, levels of atrial natriuretic peptide was significantly higher than in the other subjects, but aldosterone levels decreased to nearly those seen in the nonpregnant subjects. Atria natriuretic peptide did not establish a rhythm in normal nonpregnant and pregnant subjects, but in the studies of aldosterone levels, a clear circadian rhythm was evident. In severe cases of preeclampsia, atrial natriuretic peptide established a circadian rhythm similar to that of blood pressure, and the circadian rhythm of aldosterone disappeared. The main characteristics of the rhythm in atrial natrluretic peptide and blood pressure in women showing preeclamptic signs is that the acrophase occurred at midnight. This evidence suggests that in women with symptoms of preeclampsia the load to the atria increases at midnight. Doppler waveforms in the fetal aorta and umbilkal artery in patients with hypertension in pregnancy Cameron AD; Nicholson SF; Nimrod CA; et al Department of Obstetrics and Gynaecologv, University of Calgary, Calgary, Alta., Canada AM. J. OBSTET. GYNECOL.; 158/2 (339-345)/1988/ Pulsed doppler ultrasound assessment of blood flow was performed in the feta 1 aorta and umbilical arteries of 41 patients with hypertension in pregnancy. Patients were groups according to severity of the hypertension and the presence or absence of chronic hypertension. Doppler abnormalities were seen in two patients with chronic hypertension, both of whom delivered small for gestational age infants. Only one patient with mild to moderate preeclampsia had abnormal aortic Doppler assessment and was also delivered of a small for gestational age infant. The highest number of abnormal Doppler waveforms in both fetal aorta and umbilical artery were found in patients with severe preeclampsia. Abnormalities were detected more frequently in the fetal aorta than in the umbilical artery. Doppler assessment was often abnormal before a nonstress test or biophysical profile. The number of abnormal Doppler values correlated with perinatal outcome in patients with severe preeclampsia. Ceorgraphlc variation in the inddeocc of hypertension in pregnancy Mashalasa NN; Modissanyane FM; Daw Hla Kyi; et al Maternal and Child Health, World Health Organization, Geneva, Switzerland AM. J. OBSTET. GYNECOL.; 158/l (80-83)/1988/ Prospectively collected information on blood pressure and proteinuria was available for geographically defined populations of primigravidas in Burma, China, Thailand and Viet Nam. Clinically recognized hypertension during pregnancy varied by factor or 25 between countries, and even a strict