The renin-angiotensin system in pregnancy and parturition.
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Angiotensinogen↗
Biomedical subjects
J Milliez
Publications and source records attributed to J Milliez.
[Tolerance to veralipride administered for an extended time].
The author has studied the effects of the long-term administration (mean: 8 months) of veralipride in 12 menopausal women (7 naturally, 5 surgically). Veralipride was administered in a dose of one capsule daily, 20 days per month. Results were excellent in 4 cases, good in 6 cases and average in 2. In 9 cases out of 12, menopausal flushing totally disappeared. The study demonstrates good clinical tolerance to the drug and no repercussion on biological parameters other than a significant rise in prolactin levels.
Drug Tolerance↗
[Doppler echographic study of placental circulation of the fetus of normal and hypertensive mothers].
Foetal blood velocity wave forms, as recorded in chorionic vessels by pulsed Doppler ultrasonography, reflect vascular resistance in foetal placental circulation. The minimal-to-maximal velocity ratio provides an index of vascular conductance; the higher the minimal velocity (positive forward diastolic blood flow), the lower the vascular resistance. In the present study, this index was the same in pregnant women with normal blood pressure (n = 19) and in those with pregnancy-induced hypertension (n = 12); however, it was significantly lowered (p less than 0.001) in pregnant women with essential hypertension (n = 9). In the population of women with normal blood pressure and pregnancy-induced hypertension, a positive correlation (r = 0.71), was found between index value and gestational age, indicating a progressive fall in placental vascular resistance. All placentas from these 31 women were histologically normal except two which showed one single marginal infarct less than 1 cm in diameter. In the group of women with essential hypertension, the 6 placentas examined were pathological, with multiple chronic infarcts, placental growth retardation and maceration. Thus, pulsed Doppler ultrasonography should be used for early detection of placental vascular damage and for improved surveillance of pregnancies complicated by maternal vascular diseases.
Blood Flow Velocity↗
Fetal tachycardia and meconium staining: a sign of fetal infection.
A retrospective study was carried out on 72 liveborn babies in whom perinatal infection was suspected. Twenty-nine of the 72 neonates were effectively infected. Analysis of intrapartum FHR recordings showed that tachycardia (base line FHR above 160 beats/min) during labor, occurred more often among infected babies (P less than 0.001). When fetal tachycardia is associated with meconium stained amniotic fluid (MSAF), the relative risk of fetal infection is 51 times as great as in babies without MSAF. Fetal tachycardia is not related to maternal fever nor to prematurity. It is not a sign of limited placental or amniotic fluid infection, but implies infection of the fetus itself. Since most infected babies displayed infectious diarrhea immediately at birth, it is suggested that MSAF may eventually be due to antenatal intestinal infection and intrauterine emission of infected stools. Although great caution is advocated for the management of labor in the presence of fetal tachycardia, MSAF should not be always regarded as a sign of acute fetal distress when antenatal infection of the fetus is suspected.
Bacterial Infections↗
[Experimental prevention of a hemolytic disease of the fetus with F (ab)'2 immunoglobulin fragments].
An experimental study was designed to tentatively protect fetal red blood cells (RBC) against hemolysis by covering fetal RBC antigenic sites with F (ab)'2 fragments of hemolysing antibodies. Sheep antibodies were raised against rabbit RBC. IgG were separated and part of the IgG pool subjected to pepsin digestion, in order to isolate F (ab)'2 fragments. Near term rabbit fetuses were injected through the uterine wall with either IgG, F (ab)'2 or successively F (ab)'2 then IgG. Fetuses were extracted by hysterotomy, one hour after the last injection. Neonatal blood was collected by cardiac puncture for hematocrit determination and detection of hemolysis. Among fetuses injected with IgG alone, nine were deal at hysterotomy and evidenced diffuse hemorrhagic syndrome. Six were born alive with hemolysis, including three with severe anemia. (Ht = 26%). Nine fetuses successively injected with F (ab)'2 and then IgG, were all born alive with normal hematocrits (Ht = 43%). The protective role of F (ab)'2 fragments and their potential therapeutic use are discussed.
Animals↗
[Kidneys; hypertension and pregnancy. III. The renal risk in pregnancy].
When a woman with chronic renal disease wishes to become pregnant, the risk to the mother and the foetus is often inaccurately evaluated or exaggerated. In patients with primary nephropathy the foetal risk is significantly increased by the arterial hypertension frequently associated with renal insufficiency. In systemic lupus erythematosus (SLE) with renal involvement, the risk represented by hypertension is compounded by a high incidence of spontaneous abortion, particularly when the disease is progressive. Pregnancy seems to have little influence on SLE itself, and the classical post-partum problems are controversial. Much more dangerous are acute complications, such as cortical necrosis or haemolytic and uraemic syndromes occurring in apparently healthy women during the last trimester of pregnancy and after delivery. Urinary infections are common during pregnancy. They are heralded by asymptomatic bacteriuria which should be systematically detected, since these infections increase the likelihood of pyelonephritis with in turn increases the severity of perinatal complications.
Acute Kidney Injury↗
[Kidneys, hypertension and pregnancy. II. Hypertension in pregnancy: significance, prognosis, and treatment (author's transl)].
A rise in arterial pressure above 140 mmHg systolic or 85 mmHg diastolic is pathological in pregnant women. Such changes may either reveal chronic hypertension or constitute a purely gestational complication. The persistence or regression of abnormally high BP values 3 months after delivery retrospectively indicates whether the hypertension was chronic or pregnancy-related. When BP values are very high (diastolic above 110 mmHg) the mother is exposed to vascular accidents and the most effective anti-hypertensive drugs are required. In the more common moderate hypertension, both the mother (eclampsia) and the foetus (intra-uterine or neonatal death, low birth-weight) are at risk. The risk is better predicted by proteinuria and hyperuricaemia than by the BP values themselves, and whether anti-hypertensive drugs are warranted is uncertain. Studied comparing patients with treated and untreated moderate hypertension have yielded two valuable results: (1) methyldopa administered to the mother is harmless to the foetus, and (2) abortion during the second trimester of pregnancy is probably prevented when methyldopa is prescribed against chronic hypertension. No study has yet afforded evidence that the use of anti-hypertensive drugs in gestational hypertension benefits the foetus. Further therapeutic trials and a better knowledge of the natural history and mechanisms of hypertension in pregnancy are required before adequate management of this condition can be determined.
Antihypertensive Agents↗
[Kidneys, hypertension and pregnancy. I. Renal function in normal pregnancy (author's transl)].
Pregnancy enhances renal functioning. As early as the first week of amenorrhoea, renal plasma flow (RPF) and glomerular filtration rate (GFR) increase by 30 to 50%, with parallel rise in creatinine and urea clearances. The water and salt balance becomes strongly positive. However, the normal mechanisms of NaCl retention (aldosterone, desoxycorticosterone, oestrogens) remain active, counterbalancing the natriuretic effects of progesterone and of increased filtered sodium load. Renal regulation of the acid/base equilibrium is preserved, albeit adjusted to a higher pH threshold. At the beginning of pregnancy uric acid clearance is increased and tubular reabsorption of glucose is decreased. Blood pressure falls by 20 mmHg during the first semester. Prostaglandins and progesterone oppose the vasopressive action of angiotensin in pregnant women, and changes in their metabolism may account for the development of pre-eclampsia.
Blood Pressure↗
Antepartum fetal heart rate monitoring. A semi-quantitative evaluation of the 'non-stressed' fetal heart rate.
1964 recordings (from 246 patients were analysed on the basis of a semi-quantitative evaluation of base-line heart rate variability. All the tracings were obtained in the antepartum period, between the 20th wk of pregnancy and prior to the onset of labour. None of the recordings were made during labour or after induction of uterine activity so that a 'non-stressed' fetal heart rate test was obtained in every case. The percentage of flat tracing in each recording and the presence of sinusoidal patterns were compared with the neonatal outcome. When the tracings included a more than 50% flat pattern, 81.8% of the babies were distressed at birth. When a less than 50% flat recording was present only 11.4% of the neonates were distressed. Sinusoidal patterns were more frequently associated with abnormal tracings including those with more than 50% flat recordings. The presence of sinusoidal features did not significantly influence the neonatal outcome for tracings with a less than 50% anomaly: conversely sinusoidal patterns superimposed on a more than 50% flat tracing were predictive of fetal compromise and neonatal distress in 100% of the cases. These results allow to advocate the use of 'non-stressed' antepartum fetal heart rate monitoring, as a reliable test in the management of high risk pregnancies.
Female↗
Antepartum fetal heart rate monitoring. II. Deceleration patterns.
Fetal heart rate was studied during the antepartum period in 246 patients, yielding a total of 1964 recordings. The following parameters were evaluated and correlated: --the semi-quantitative assessment of fetal heart rate instability (as expressed by the percentage of duration of flat traces); --the presence of decelerations and their relationship to the presence or absence of uterine contractions; --the neonatal condition. Overall, 50% of the patients exhibited uterine contractions while 30% contained decelerations patterns either occurring spontaneously or in association with uterine contractions. A definite relationship was observed between the presence of severe decelerations (irrespective of the time relationship with any uterine contraction) and poor neonatal outcome. A relationship does exist between the presence of severe decelerations and flattening in the recording, which, as demonstrated in the previous part of the paper also exhibited a strong positive relationship with the neonatal outcome. When one considers the different degrees of flattening, it appears that a further correlation between decelerations and neonatal state is demonstrable only in the case of a 10--50% flat recording. Here the probability of a distressed baby is 20% in the absence of decelerations, but 43.4% in the presence of decelerations. In other cases (i.e., less than a 10% or more than a 50% flat recording) the pronostic significance of the instability of the record is not significantly modified by he presence or absence of decelerations. These results indicate that consideration of decelerations is only advisable in these cases where instability is moderately affected (flattening in 10-50% of the record) and that the use of the oxytocin challenge test OCT may be reserved for such cases, when these are neither spontaneous contractions nor decelerations and not contraindications present.
Apgar Score↗
Antepartum fetal heart rate monitoring. III. Fetal movements and accelerations in fetal heart rate.
This third part of the paper deals with the study of the relationships between fetal movements, fetal heart rate accelerations associated with such movements, fetal heart rate instability and neonatal outcome. No correlations has been found between absence of fetal movements and neonatal distress. A correlation has been found between the lack of fetal heart rate accelerations, the flatness of the record and poor neonatal outcome. In extreme situations (i.e. flatness in less than 10% of the record or in more than 80%) the presence or absence of accelerations does not add further useful information. Such information, however, is gained in the intermediary situations (the 'combined' recordings) and particularly when the record is between 51 and 80% flat where there appears to be an 85.6% risk to the fetus. Consequently, when trying to analyse an antenatal record it seems advisable to take primarily into account the percentage of flat recordings (providing the records are numerous enough and of sufficient length). Then, in records between 10 and 50% flat, the presence or the lack of spontaneous decelerations requires consideration whereas, when the record is between 51 and 80% flat, it is the presence or absence of fetal heart rate accelerations which is important.
Apgar Score↗
Release of vasopressin by the fetal lamb during premature parturition induced with corticotropin.
These studies were implemented to assess the relationship between fetal vasopressin secretion and the progression of parturition as well as the contribution of specific stimuli to vasopressin release during labor. In chronically catheterized fetal lamb preparations, labor was induced by infusion of adrenocorticotropin (12.5 mg/kg/hr) to seven fetuses at 130 +/- 1 day of gestation. Before labor, fetal plasma vasopressin concentrations were 2.1 +/- 1.4 pg/ml and remained low (5.3 +/- 3.4 pg/ml) during prodromal and early phases of labor, but rose significantly in the active and expulsive phases (39.6 +/- 27.5 and 173.3 +/- 152.9 pg/ml) to reach peak values at delivery (584.2 +/- 433 pg/ml) and decrease by 30 min after birth (359.8 +/- 90.0 pg/ml). At delivery, fetal plasma vasopressin concentrations were strongly correlated (P less than 0.001) with hormone values obtained during the latter phases of labor. Fetal arterial pH and oxygen tension was inversely correlated with plasma vasopressin (P less than 0.01). No similar correlations were found with arterial PCO2, K, Na, Cl, osmolality, or packed cell volume. Unexpectedly, we observed a significant (P less than 0.001) and progressive decrease in fetal oxygen tension during the induction process. Other characteristics of adrenocorticotropin-induced parturition seemed to mimic those of spontaneous labor.
Adrenocorticotropic Hormone↗
A case report of maternal death associated with betamimetics and betamethasone administration in premature labor.
A fatal case of pulmonary edema is reported after prolonged treatment with beta-mimetics during pregnancy for threatened premature labor. The mother had received betamethasone in order to enhance fetal lung maturity. Myocardial failure occurred 5 days after discontinuation of betamimetics. The potential toxic effects of beta-adrenergic agents and their association with corticosteroids are discussed. Caution is recommended when high doses of betamimetics are to be delivered to prevent premature labor. No patient should be treated unless her cardiac condition is normal. Cardiovascular evaluation should be regularly performed during the course of treatment. No patient should be discharged after treatment without a normal cardiovascular check-up.
Adrenergic beta-Agonists↗
Renal response of fetal lamb to complete occlusion of umbilical cord.
The renal response of the fetal lamb to repeated complete occlusion of the umbilical cord was studied in nine chronically instrumented animals. Five episodes of occlusion of the umbilical cord, each lasting for two minutes, produced a twofold rise in fetal urine osmolality and sodium, chloride, and potassium concentrations. Output of urine and glomerular filtration rate remained essentially unchanged while free water clearance decreased from a control of +0.10 to -0.02 ml. per kilogram per minute at the end of the fifth episode. Electrolyte concentrations in urine remained elevated for at least two hours following the occlusions. In addition to changes in urine composition, there was a 50- to 200-fold increase in the fetal plasma concentration of vasopressin. These studies indicate that complete interruption of the umbilical circulation, even though of short duration, produces disturbances in fetal renal function that can lead to loss of electrolytes in the urine. They provide an explanation for the low sodium levels reported in asphyxiated newborn infants in renal failure.
Acid-Base Equilibrium↗
Usefulness of fluorescence in situ hybridization for the diagnosis of Turner mosaic fetuses with small ring X chromosomes.
OBJECTIVE: To emphasize the usefulness of fluorescence in situ hybridization (FISH) techniques on uncultured amniocytes for the diagnosis of abnormal mosaic karyotypes. METHODS: In the course of three prenatal diagnoses, specific fluorescent probes, coding, respectively, for chromosomes X, Y, 18, 13, and 21, were applied on amniocyte preparations directly after amniocentesis. At least 50 nuclei were counted in each case. Parallel to the FISH procedure, cell cultures were set up in order to obtain karyotypes. FISH and cytogenetic results were then compared. RESULTS: In each case, FISH showed an abnormal mosaic chromosomal constitution, 45,X/46,XX, which was related to the existence of tiny ring X chromosomes in karyotypes. CONCLUSION: Because very small ring X chromosomes can escape identification when standard cytogenetic techniques are used alone, we show that misdiagnosis can be avoided when FISH is performed beforehand.
Adult↗
Obstetrical advantages and perinatal risks of indomethacin: a report of 818 cases.
In a series of 818 patients treated with indomethacin during pregnancy, the rate of perinatal complications was 1.8%. The risk was increased to 13% if indomethacin was being taken at the time of delivery, and when treatment was prolonged. The serious nature of certain complications (persistence of fetal circulation and oligo/anuria) means that indomethacin should only be used in cases in which betamimetic drugs are formally contraindicated or if there is a risk of unacceptable prematurity. Even in such cases, indomethacin should only be given for short period (< 1 week).
Delivery, Obstetric↗
[The severe acute colitis syndrome. Prognosis evaluation. A report of one hundred cases (author's transl)].
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Acute Disease↗
[The treatment of hypertension in pregnancy (author's transl)].
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Adult↗