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M A Belfort

Publications and source records attributed to M A Belfort.

At least 19 recordsLinked to original sources
PubMed2001

The effect of 17beta-estradiol on isolated omental arteries from preeclamptic women.

OBJECTIVE: To study the effect of 17beta-estradiol on isolated omental arteries from preeclamptic women. STUDY DESIGN: Rings of omental artery with intact endothelium were mounted in organ chambers for isometric tension recording. We studied the effect of pharmacological concentrations of 17beta-estradiol on potassium chloride-induced tension and the concentration-contraction relationships for norepinephrine and calcium. RESULTS: Cumulative application of 17beta-estradiol, in a concentration-dependent manner, relaxed potassium chloride contracted rings. Sixty minutes of incubation with 17beta-estradiol (10(-5)mol/l) attenuated the tension developed in response to potassium chloride, norepinephrine and calcium. Tamoxifen (10(-6)mol/l) did not antagonize the inhibitory actions of 17beta-estradiol. CONCLUSIONS: Pharmacological concentrations of 17beta-estradiol retain the capability for relaxing omental artery rings from preeclamptic women. The loss of refractoriness to norepinephrine, increased responsiveness to calcium ions and decreased ability of 17beta-estradiol to inhibit calcium-induced tension may be responsible for increased vascular reactivity in preeclampsia.

Adult↗
PubMed2001

Obstetric uses of intravenous immunoglobulin: successes, failures, and promises.

Intravenous immune globulin (IVIG) is approved for use in a number of conditions that may occur in obstetrical patients, including autoimmune thrombocytopenia and immune deficiency syndromes. IVIG also is widely used in obstetrics for nonapproved indications, such as fetal-neonatal alloimmune thrombocytopenia, antiphospholipid syndrome, and recurrent miscarriage. This review critically analyzes the use of IVIG for these indications based on the best available information. The authors conclude IVIG is effective in the management of fetal-neonatal alloimmune thrombocytopenia. IVIG appears promising as a treatment for severe fetal-neonatal alloimmune hemolysis due to antierythrocyte antibodies. A prospective multicenter trial should be undertaken. IVIG is no more effective than heparin and low-dose aspirin in the treatment of pregnancies complicated by antiphospholipid syndrome but has not been adequately evaluated in refractory cases. Finally, pending convincing studies, IVIG is not effective and should not be used for the management of recurrent miscarriage.

Abortion, Habitual↗
PubMed2001

Inhibition of cyclooxygenase but not nitric oxide synthase influences effects on the human omental artery of the thromboxane A2 mimetic U46619 and 17beta-estradiol.

OBJECTIVE: These experiments were performed to study the influence of endothelial factors on the contractile effect of the thromboxane A(2) analog U46619 and on the relaxant action of 17beta-estradiol on isolated human omental arteries from nonpregnant women, women with normal pregnancies, and women with preeclampsia. STUDY DESIGN: Arterial rings (3 mm) with or without endothelium were suspended in organ chambers filled with Krebs buffer, 37 degrees C, aerated with 5% carbon dioxide in air, pH approximately 7.4, for isometric tension recording. Rings were incubated with indomethacin, N(omega)-nitro-L -arginine, or 17beta-estradiol, alone or in combination. The concentration that produced 50% of maximal effect, the area under the curve, and the maximal effect of U46619, normalized with respect to a reference contraction in response to potassium chloride, were compared. RESULTS: Neither indomethacin nor N(omega)-nitro-L -arginine changed the basal tone of omental artery rings. Neither N(omega)-nitro-L -arginine nor removal of the endothelium affected either the contractile action of U46619 or the relaxant action of 17beta-estradiol. In contrast, indomethacin potentiated the contractile effect of U46619 and abolished the inhibitory effect of 17beta-estradiol in rings from all three groups. The effects of U46619 and 17beta-estradiol were significantly less in rings from women with normal pregnancy than in those from women with preeclampsia. Tissues from women with preeclampsia demonstrated the highest contractile response to U46619. CONCLUSION: The inhibitory effect of 17beta-estradiol is not due to increased production of endothelial nitric oxide but rather involves inhibitory products of the cyclooxygenase pathway. The effect of indomethacin may result from inhibited production or release of eicosanoids or from sensitization of thromboxane A(2) receptors.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2001

Pregnant women with chronic hypertension and superimposed pre-eclampsia have high cerebral perfusion pressure.

OBJECTIVE: To determine any differences in cerebral perfusion pressure in patients with chronic hypertension compared with those with chronic hypertension and superimposed pre-eclampsia. DESIGN: A prospective observational study. SETTING: University hospital clinic and labour and delivery suite. PARTICIPANTS: Fifteen women with chronic hypertension and 15 with superimposed pre-eclampsia. METHODS: Transcranial Doppler ultrasound was used to measure blood velocity in the middle cerebral arteries of the patients. Systemic blood pressure in the brachial artery was measured simultaneously. Middle cerebral artery. resistance index, pulsatility index, and cerebral perfusion pressure were calculated and plotted on the same axes as data from normal pregnant women. Cerebral perfusion pressure values outside of the 5th and 95th centiles were regarded as abnormal. Cerebral perfusion pressure data from the chronic hypertension and superimposed pre-eclampsia groups were also expressed in terms of the number of normative standard deviations from the mean value for normal pregnancy (Multiples of the Standard Deviation: MOS). All studies were conducted before labour, under similar conditions, and before volume expansion or treatment. Statistical analysis was by Student's t test and Fisher's exact test as appropriate with significance set at a two-tailed P<0.05. RESULTS: Patient demographics and blood pressure were not significantly different between the two groups. The resistance index and pulsatility index were not significantly different (neither absolute nor multiples of the standard deviation values). The absolute cerebral perfusion pressure was significantly higher in the patients with superimposed pre-eclampsia. The group of women with superimposed pre-eclampsia had a significantly higher mean value of cerebral perfusion pressure measured as multiples of the standard deviation from the mean value for normal pregnancy, despite there being no blood pressure difference. CONCLUSIONS: Superimposed pre-eclampsia is associated with significantly higher cerebral perfusion pressure measurements compared with women with uncomplicated chronic hypertension. This is not directly related to a higher blood pressure. The difference in cerebral perfusion pressure may be used to speculate upon the pathophysiology of the increased risk for eclampsia seen in patients with superimposed pre-eclampsia.

Adult↗
PubMed2001

Changes in flow velocity, resistance indices, and cerebral perfusion pressure in the maternal middle cerebral artery distribution during normal pregnancy.

BACKGROUND: There are few longitudinal data currently available detailing the normal changes in maternal cerebral hemodynamics during human pregnancy. This lack of information limits the study of pregnancy-associated cerebrovascular adjustments and, in particular, preeclampsia, where the brain appears to be especially susceptible to ischemic and encephalopathic injury. Our objective was to define the hemodynamic changes, specifically velocity, resistance indices, and cerebral perfusion pressure, in the middle cerebral artery (MCA) distribution of the brain during normal pregnancy. METHODS AND MATERIALS: Transcranial Doppler ultrasound was used to determine the systolic, diastolic and mean blood velocities in the middle cerebral arteries in non-laboring women studied longitudinally during normal gestation. The resistance index (RI), pulsatility index (PI), and cerebral perfusion pressure (CPP) were calculated using the velocity and blood pressure data. Data were analyzed using a longitudinal statistical model incorporating random patient effects and a homoscedastic (compound symmetric) variance-covariance structure over time (gestational age). The predicted mean value (Least Squares Mean), and the 5th and 95th percentiles, were defined for normal pregnancy. RESULTS: MCA systolic velocity decreased (24%) as did the mean velocity (17%). The diastolic velocity did not change significantly. The MCA RI decreased by 19% and the PI decreased by 25%. The MCA CPP increased by 52% between 12 and 40 weeks of gestation. CONCLUSIONS: The normative ranges for MCA velocity, RI, and CPP have been defined in normal human pregnancy using longitudinally collected data. By having a defined normal range, identification of abnormalities in cerebral hemodynamics during pregnancy is now possible, and this may help researchers and clinicians to elucidate etiologies and treatments for pregnancy-related pathophysiologic states such as preeclampsia

Adult↗
PubMed2001

Cerebrovascular reactivity in normal pregnancy and preeclampsia.

OBJECTIVE: To compare cerebrovascular reactivity in normotensive and preeclamptic pregnant women. METHODS: Transcranial Doppler ultrasound was used to measure peak, end-diastolic, and mean velocities in the middle cerebral arteries of 45 normotensive and 36 preeclamptic women in the third trimester. All measurements were done in the left lateral position at baseline, during 5% carbon dioxide (CO2) inhalation, and during an isometric hand-grip test. Blood pressure (BP), heart rate, oxygen (O2) saturation, and end-tidal partial pressure of carbon dioxide (pCO2) were recorded with each Doppler measurement. The mean pulsatility index (PI), resistance index (RI), and cerebral perfusion pressure at each time was compared using two-way repeated measures analysis of variance. Cerebrovascular reactivity, calculated as the percentage change in response to each maneuver, was also compared using analysis of covariance. A post hoc power analysis was performed to evaluate the primary measures of the study (middle cerebral artery PI and RI). Using alpha error of 5%, the statistical power to identify a difference in PI and RI in women with preeclampsia compared with normotensive women was 90% and 67%, respectively. The statistical power to identify a difference in PI and RI in response to the two maneuvers was 69% and 53%, respectively. Statistical significance was set at P <.05. RESULTS: Preeclamptic women had higher baseline cerebral perfusion pressure (90.4 compared with 61.9 mmHg, P <.05) and lower PI (0.64 compared with 0.76, P <.05) and RI (0.46 compared with 0.51, P <.05) than normotensive pregnant women. In normotensive patients, both 5% CO2 inhalation and isometric hand-grip test caused a significant decrease in PI (-9.5% and -6.1%, respectively) and RI (-6.5% and -4.2%, respectively). In contrast, in preeclamptic patients there was no change in any of the middle cerebral artery parameters in response to either maneuver. CONCLUSION: Normotensive pregnant women had normal middle cerebral artery responses to both 5% CO2 inhalation and isometric hand-grip test. Preeclamptic patients had elevated baseline cerebral perfusion pressure and reduced vasodilatory responses to both tests. These findings are consistent with a state of vasoconstriction in preeclamptic women that is unresponsive to stimuli that under normal circumstances result in vasodilation.

Adult↗
PubMed2000

Evaluation of a noninvasive transcranial Doppler and blood pressure-based method for the assessment of cerebral perfusion pressure in pregnant women.

OBJECTIVE: We have developed a Doppler method for the estimation of cerebral perfusion pressure (CPP) using noninvasive techniques. Our objective was to evaluate our new method in pregnant women. METHODS AND MATERIALS: Laboring women with a lumbar epidural in situ had transcranial Doppler interrogation of the maternal middle cerebral artery (MCA) to measure systolic, diastolic, and mean velocities. A pressure transducer was connected to the epidural catheter and pressure was recorded. Systolic (SBP), diastolic (DBP), and mean (MAP) blood pressure were taken with a Dinamap monitor. Doppler estimated CPP (mm Hg) = [V(mean)/(V(mean) - V(diastolic)](MAP - DBP) and directly measured CPP = MAP - Epidural pressure data were plotted on a Bland-Altman graph with limits of agreement. The mean difference (the mean of the sum of both positive and negative differences) and absolute difference (the mean of the sum of the absolute differences) were calculated. In addition, linear and polynomial regression analyses were performed. RESULTS: Twenty laboring women were studied. All had normal pregnancies. The mean maternal age was 28 +/- 7 years and the mean gestational age was 39 +/- 2 weeks. The mean maternal MAP was 77 +/- 12 mm Hg. The Bland-Altman plot showed a mean difference of 2.2 mm Hg at a mean CPP of 65 +/- 12 mm Hg; with a standard deviation of 4.8 mm Hg, the absolute difference was 3.9 +/- 3.0 mm Hg at a mean CPP of 65 +/- 12 mm Hg. The regression analysis showed an r = 0.92, r(2) = 0.86, and p < 0.0001. CONCLUSIONS: Our formula allows the estimation of CPP using a simple calculation and noninvasively acquired data. This method may be of use for frequent, easy, and accurate CPP and intracranial pressure estimation and may, as such, have significant research and clinical applications.

Adult↗
PubMed1999

Effects of blood pressure on orbital and middle cerebral artery resistances in healthy pregnant women and women with preeclampsia.

OBJECTIVE: The object of the study was to test the hypothesis that preeclampsia leads to an abnormal vascular response to increasing blood pressure in cerebral vessels by analyzing the relationship between mean arterial pressure and resistance index in the central retinal, ophthalmic, and middle cerebral arteries in women with normal pregnancies and women with preeclampsia. STUDY DESIGN: Transcranial and color flow Doppler ultrasonographic studies were used to determine systolic, diastolic, and mean velocities and the resistance indexes in the central retinal, ophthalmic, and middle cerebral arteries in 24 women with normal pregnancies and 18 women with preeclampsia. In each group the relationship between the mean arterial pressure and the resistance index was determined for each artery by means of linear regression analysis. The Pearson correlation coefficients for each mean arterial pressure versus resistance index relationship were compared between the groups. In a separate analysis middle cerebral artery data obtained from 79 women with preeclampsia (with and without headache) were compared with data from the normal pregnancy group and analyzed in terms of the relationship between mean arterial pressure and resistance index. RESULTS: The resistance index in women with normal pregnancies decreased with increasing mean arterial pressure in all 3 vessels studied (ophthalmic artery r = -0.33, central retinal artery r = -0. 43, middle cerebral artery r = -0.30). In the women with preeclampsia, however, as mean arterial pressure increased the resistance index increased in the orbital vessels and decreased in the middle cerebral artery (ophthalmic artery r = 0.54, central retinal artery r = 0.65, middle cerebral artery r = -0.25). The correlation coefficients in the women with preeclampsia were significantly different from those in the women with normal pregnancies for the ophthalmic and central retinal arteries (P =. 001) but not for the middle cerebral artery (P =.8). Within-group analysis in the patients with normal pregnancies showed no differences between the correlation coefficients of the studied vessels. In the women with preeclampsia the ophthalmic artery (P =. 02) and the central retinal artery (P =.005) were significantly different from the middle cerebral artery but not from each other. Women with preeclampsia who had headache had a different correlation coefficient for the middle cerebral artery than did those without headache (r = -0.34 versus r = 0.23; P <.001). The correlation coefficient for the middle cerebral artery for women with preeclampsia without headache was not significantly different from the central retinal artery and ophthalmic artery correlation coefficients in the general preeclampsia group. CONCLUSIONS: Women with preeclampsia demonstrate a different relationship between blood pressure and resistance index in the ophthalmic and central retinal arteries than do women with normal pregnancies. In the middle cerebral artery, however, preeclampsia does not appear to affect the resistance index response to increasing mean arterial pressure in women with headache. In women with preeclampsia without headache the relationship seen in the ophthalmic artery and central retinal artery is preserved in the middle cerebral artery. This may indicate a failure in the autoregulatory capacity of the middle cerebral artery in the presence of headache. Alternatively, the resistance index response in the ophthalmic artery and central retinal artery may represent small-caliber vessel vasospasm that is not present in the middle cerebral artery in women with preeclampsia who have headache.

Adult↗
PubMed1999

Change in estimated cerebral perfusion pressure after treatment with nimodipine or magnesium sulfate in patients with preeclampsia.

OBJECTIVE: Data are accumulating to suggest that cerebral perfusion pressure may be either abnormally high or low in preeclampsia and eclampsia. Little is known of the cerebral perfusion pressure effects of magnesium sulfate or nimodipine. Our objective in this study was to compare the change in cerebral perfusion pressure in patients with severe preeclampsia randomly selected to receive nimodipine or magnesium sulfate. STUDY DESIGN: Patients with severe preeclampsia were randomly selected to receive magnesium sulfate (6 g bolus and 2 g/hr intravenous infusion) or nimodipine (60 mg taken orally every 4 hours). Transcranial Doppler ultrasonography was used to measure flow velocities in the right and left middle cerebral arteries, and the results were averaged. Measurements were obtained before treatment (baseline) and 30 minutes after the magnesium sulfate bolus was completely infused or 30 minutes after the nimodipine was ingested. Studies were performed before any other intervention. The person performing the ultrasonography was unaware of the patient's group assignment. Estimated cerebral perfusion pressure was calculated with the following formula: Estimated cerebral perfusion pressure = Velocity(mean) x [(Blood pressure(mean ) - Blood pressure(diastolic ))/(Velocity(mean) - Velocity(diastolic ))]. The difference between estimated cerebral perfusion pressure at baseline and after treatment was compared between the 2 groups by means of the Mann-Whitney rank sum test. RESULTS: Nine patients were randomly selected to receive nimodipine and 12 to receive magnesium sulfate. Patient demographics and severity of condition were not significantly different between the 2 groups. The change in estimated cerebral perfusion pressure was significantly different between the groups. Estimated cerebral perfusion pressure increased after nimodipine use and decreased after magnesium sulfate use. CONCLUSION: Shortly after administration to patients with severe preeclampsia, nimodipine resulted in increased cerebral perfusion pressure in comparison with magnesium sulfate.

Adult↗
PubMed1999

Prevention of eclampsia.

Eclampsia continues to be a major cause of maternal morbidity and mortality rates, especially in underdeveloped nations. Our data indicate that eclampsia may represent the end stage of at least two very different pathophysiological pathways: one in which cerebral perfusion is low because of vasospasm and another in which cerebral perfusion is increased because of abnormal autoregulation and a failure of the normal protective mechanisms. Magnesium sulfate has been extensively used in the management and prevention of eclamptic seizures in the United States and has been recently shown to be superior to both diphenylhydantoin and diazepam. We have shown that magnesium sulfate is a potent vasorelaxant and that its action may depend on improving cerebral perfusion. Nimodipine, a calcium channel blocker with selective cerebrovascular effect, is currently under investigation in severe preeclampsia. The data show that it is as effective as magnesium sulfate in preventing eclampsia, with less maternal and fetal side effects. Magnesium sulfate and nimodipine have opposite effects on the estimated cerebral perfusion pressure as determined with the Doppler ultrasound. We speculate that the estimated cerebral perfusion pressure may be used to determine the type of cerebrovascular abnormality and the most appropriate treatment in each individual patient with preeclampsia.

Antihypertensive Agents↗
PubMed1999

Forceps-assisted vaginal delivery.

Operative vaginal delivery using forceps has been an important part of obstetric practice for nearly 400 years. Countless women and their children have benefited from timely and expertly performed procedures. Physicians must, therefore, make every effort to retain these skills, to modify and improve them in every possible way, and to pass them on. In this way, women and children of future generations will benefit from the many years of experience that have gone before them.

Equipment Design↗
PubMed1999

Association of cerebral perfusion pressure with headache in women with pre-eclampsia.

OBJECTIVE: To study estimated cerebral perfusion pressure and its relation to headache and scotomata in women with pre-eclampsia. DESIGN: Prospective, observational study. SETTING: University teaching hospitals. POPULATION: Seventy-nine pre-eclamptic women with (n = 42) and without (n = 37) headache. Patients with scotomata were also studied separately. METHODS: Transcranial Doppler ultrasound was used to estimate the resistance index, pulsatility index, and estimated cerebral perfusion pressure in the middle cerebral artery. eCPP data were plotted on the same axes as the mean (and 5th and 95th% prediction limits) eCPP data from 63 normal pregnant women followed longitudinally through pregnancy. Data outside of the 95% prediction limits were regarded as abnormal. Data from the pre-eclamptic women were also expressed in terms of the number of standard deviations from the mean value established for normal pregnancy (multiples of the standard deviation: MOS). All studies were prior to labour, under similar conditions, and before volume expansion or treatment. Analysis of data was performed using Student's t test, Mann-Whitney U test, ANOVA, and Fisher's exact test with two-tailed P < 0.05, and receiver operating characteristic curve analysis with a one-tailed P < 0.05. MAIN OUTCOME MEASURES: Resistance index, pulsatility index, and eCPP. RESULTS: Pre-eclamptic women with headache were much more likely to have abnormal eCPP (34/42; 88%) than those without headache (18/37; 49%), P = 0.004, OR 4.5 (95% CI 1.5 to 13.9). There were no differences in terms of MOS in the resistance index or pulsatility index between the two groups, but estimated perfusion pressure, expressed as multiples of the standard deviation in the group with headache, was significantly higher than in the women without. Headache was noted in both over-perfusion and under-perfusion states. Only women with headache had scotomata, and their presence was not related to the severity of the headache or any difference in resistance indices or eCPP. CONCLUSIONS: Headache in women with pre-eclampsia is strongly associated with the presence of abnormal cerebral perfusion pressure. This information may be of use in clinical management.

Adult↗
PubMed1999

Preeclampsia may cause both overperfusion and underperfusion of the brain: a cerebral perfusion based model.

BACKGROUND: The hypothesis was that low cerebral perfusion pressure is more common in women with mild preeclampsia as compared to those with severe preeclampsia, while high cerebral perfusion pressure is more common in women with severe preeclampsia than in women with mild preeclampsia. DESIGN: Prospective, observational study. SETTING: University teaching hospitals. METHODS: Transcranial Doppler ultrasound was used to measure the blood velocity in the middle cerebral arteries of 54 patients with mild preeclampsia and 44 patients with severe preeclampsia. Blood pressure was measured simultaneously. Cerebral perfusion pressure was calculated and plotted on the same axes as data from 63 normal pregnant women. Data outside of the 95% prediction limits were regarded as abnormal. All studies were prior to labor, and before volume expansion or treatment. ANALYSIS: Student's t-test, Mann Whitney U test, and Fisher's exact test as appropriate with two-tailed p<0.05. MAIN OUTCOME MEASURE: The number of patients in each group with cerebral perfusion pressure values outside the normal 95% prediction limits. RESULTS: Almost the same number of women with mild (21/54=39%) and severe (15/44=34%) preeclampsia had measurements within the normal range (p=0.78). Mild preeclamptic women were more likely to have low (28/54=52%) rather than high cerebral perfusion pressure (p<0.001), while severe preeclamptics were more likely to have high cerebral perfusion pressure (26/44=59%) than low (p<0.001). CONCLUSIONS: In preeclampsia the brain can be normally perfused, underperfused and over-perfused. Although many women with mild preeclampsia will have underperfusion (52%), and a significant number of women with severe preeclampsia will have overperfusion (59%), many preeclamptic women have cerebral perfusion within the normal range.

Adult↗
PubMed1998

Ultrasonographic measurement of crown-rump length in high-order multifetal pregnancies.

The objective of the study was to evaluate the crown-rump length (CRL) in high-order multifetal pregnancies (three or more fetuses). The records of patients who underwent multifetal pregnancy reduction were reviewed. The following parameters were defined: the mean CRL (CRLMEAN) and the difference between the largest and smallest CRL (CRLRANGE) for each pregnancy. CRLMEAN was plotted versus gestational age (GA) and the line of best fit was derived. The residual for each CRL (CRLRES) was calculated by subtracting the value predicted by the regression line from the individual CRL (CRLIND). Regression lines for single-tons with confirmed GA from four previously reported studies were used for comparison. A total of 82 patients were included (29 triplets, 38 quadruplets and 15 quintuplets; mean GA 10.7 +/- 0.78 weeks). CRLMEAN correlated with GA (CRLMEAN = 38.88 - 8.78(GA) + 0.82(GA)2; R = 0.83; R2 = 0.70). This second-degree polynomial remained within the range for singletons. No significant differences in maternal age, GA and CRLMEAN were noted between the patients with different numbers of fetuses. The median CRLRANGE was largest in quintuplets, followed by quadruplets and triplets. The CRLRANGE correlated poorly with GA. The mean CRL in multifetal pregnancies increases with GA similarly to that in singletons. The variability of individual measurements increases with the number of fetuses and CRLs are lower in quintuplets.

Adult↗
PubMed1998

Diagnosis and management of placenta percreta: a review.

A review of the clinical decisions, diagnostic, and surgical methods in managing patients with placenta percreta was done by conducting a MEDLINE computerized search from January 1991 to January 1997 using the key words "placenta percreta," "placenta previa," "acute normovolemic hemodilution," and "erythropoietin use." Additional sources were identified through cross-referencing. We reviewed all published reports and articles regarding the clinical and surgical management of placenta percreta and nontraditional ways to treat or prevent anemia in these cases (including acute normovolemic hemodilution and erythropoietin use). The diagnosis of placenta percreta using different ultrasonographic criteria is reliable. Clinical and surgical methods of managing placenta previa with a high risk of percreta are all based on prevention of uncontrolled hemorrhage. Ninety percent of these patients will lose more than 3000 ml intraoperatively and will require blood transfusion. To avoid serious maternal morbidity secondary to hypovolemia, several options are available: erythropoietin use, acute normovolemic hemodilution, selective arterial embolization, prophylactic uterine, or hypogastric artery ligation. With the increasing incidence of placenta percreta, the clinician must use all available methods to accurately diagnose this condition. Adequate preparation and good surgical technique will help reduce maternal mortality and morbidity related to this condition.

Erythropoietin↗
PubMed1997

Persistent cerebrovascular changes in postpartum preeclamptic women: a Doppler evaluation.

OBJECTIVE: Our goal was to evaluate the cerebral vasculature in postpartum normotensive and preeclamptic women. STUDY DESIGN: Nineteen previously preeclamptic women and 19 matched normotensive controls were studied at 6 weeks, and 8 preeclamptic women and 28 normotensive controls were studied at 12 weeks post partum. Systolic, diastolic, and mean velocities, as well as resistance and pulsatility indexes, of the middle cerebral, ophthalmic, and central retinal arteries were recorded. Data are presented as median and range. Statistical significance was set at p < 0.05. RESULTS: There were no differences in maternal age, parity, heart rate, mean arterial pressure, and proteinuria between the two groups at 6 and 12 weeks post partum. At 6 weeks post partum the preeclamptic group had higher ophthalmic artery diastolic velocity (9.0 cm/sec, 3.1 to 22.3, vs 5.4 cm/sec, 3.0 to 20.1; p = 0.008), ophthalmic artery mean velocity (6.0 cm/sec, 8.8 to 34.8, vs 12.5 cm/sec, 6.8 to 35.4; p = 0.03), and central retinal artery systolic velocity (10.0 cm/sec, 7.6 to 28.0, vs 8.4 cm/sec, 5.2 to 18.3; p = 0.02). The ophthalmic artery resistance index (0.72, 0.43 to 0.88, vs 0.79, 0.66 to 0.90; p = 0.03) and ophthalmic artery pulsatility index (1.56, 0.94 to 2.82, vs 2.03, vs 1.13 to 3.10; p = 0.04) were lower in the preeclamptic group. At 12 weeks post partum the preeclamptic group had elevated ophthalmic artery mean velocity (14.5 cm/sec, 7.9 to 20.2, vs 10.9 cm/sec, 5.5 to 15.4 p = 0.01), central retinal artery systolic velocity (11.1 cm/sec, 6.8 to 15.9, vs 8.5, 5.1 to 15.3; p = 0.02), and central retinal artery diastolic velocity (3.9 cm/sec, 1.2 to 5.2, vs 3.0, 1.4 to 5.8; p < 0.05). CONCLUSION: In the postpartum period preeclamptic women show persistently elevated central retinal artery systolic velocity, which suggests distal vasoconstriction.

Adolescent↗