Decreased amniotic fluid index in low-risk pregnancy.

OBJECTIVE: To evaluate the perinatal outcomes of pregnancies complicated by isolated decreased amniotic fluid volume (AFI) after 30 weeks' gestation (AFI < or = 5 or > 5 cm but < 2.5th percentile). STUDY DESIGN: We retrospectively studied 150 low-risk singleton pregnancies > 30 weeks' gestation with decreased AFI. We also compared the outcomes of 57 pregnancies with AFI < or = 5 cm to those of 93 pregnancies with AFI > 5 cm but < 2.5th percentile (borderline AFI). Pregnancy outcome was assessed with respect to antepartum, intrapartum and neonatal measures. Statistical significance (P < .05) between groups was determined by means of the Student t test and chi 2 analysis. RESULTS: There were no statistically significant differences between pregnancies with AFI < or = 5 cm and those with AFI > 5 cm but < 2.5th percentile with respect to labor induction for an abnormal nonstress test (7.0% vs. 7.5%, overall 7.3%), cesarean sections for fetal heart rate abnormalities (7.0% vs. 7.5%, overall 7.3%), presence of meconium (16.1% vs. 15.7%, overall 16%) and Apgar score < 7 at five minutes (0 vs. 1.1%, overall 0.66%). There were no perinatal deaths in either group. Antepartum variable decelerations were more common in pregnancies with AFI < or = 5 cm as compared to those with AFI > 5 cm but < 2.5th percentile (63.1% vs. 45.1%, P = .007; overall 53.3%). CONCLUSION: With antepartum monitoring, perinatal outcome in low-risk pregnancies with an isolated decreased AFI after 30 weeks' gestation (< or = 5 or > 5 cm but < 2.5th percentile) appears to be good.

Determination of fetal occiput position by ultrasound during the second stage of labor.

OBJECTIVE: To investigate whether ultrasonography is superior to vaginal examination for determination of fetal occiput position during the second stage of labor. METHODS: We conducted a prospective cohort study of 44 parturients. During the second stage of labor, an attending obstetrician performed a vaginal examination to detect fetal occiput position. This was followed by combined abdominal and perineal ultrasound examination. The two methods were compared to the true position. Results were analyzed using Student's t test for quantitative parameters. McNemar's and Fisher's exact tests were applied in order to examine differences between the study groups. RESULTS: The error rate in detecting fetal occiput position was significantly lower using the ultrasound technique (6.8%) compared to vaginal examination (29.6%, p = 0.011). Parity, maternal body mass index or fetal weight had no influence on the error rate. CONCLUSIONS: Ultrasonographic determination of the fetal position is an accurate technique and is superior to vaginal examination.

Axial growth of the fetal eye and evaluation of the hyaloid artery: in utero ultrasonographic study.

The aims of this prospective, cross-sectional study were to report axial ocular growth during human gestation, to determine the presence of the hyaloid artery (HA) and its blood flow, and to provide a timetable for HA regression. The study group comprised 231 low-risk singleton pregnancies between 14 and 38 weeks' gestation. Ocular axial length (OAL), anterior chamber depth (ACD) and posterior chamber depth (PCD) were measured using high-resolution ultrasound. The growth of these eye segments in correlation with gestational age (GA) was established. The presence of the HA and its regression were determined. By using power Doppler, ultrasound blood flow within the HA was estimated. HA regression is a gradual process that is not evident before 18 weeks' gestation. In all fetuses beyond 29 weeks' gestation, no HA could be detected (P<0.001). Blood flow within the HA was documented only until the 16th week of gestation. The correlation coefficients, r=0.924, 0.784 and 0.929, for OAL, ACD and PCD, respectively, were found to be highly statistically significant (P<0.0001). The present data offer normative measurements of the fetal axial eye lengths, timetable for HA regression and flow cessation.

End-tidal carbon monoxide measurements in women with pregnancy-induced hypertension and preeclampsia.

OBJECTIVE: We sought to compare the end-tidal carbon monoxide breath levels in pregnant women with and without pregnancy-induced hypertension and preeclampsia. STUDY DESIGN: We prospectively performed end-tidal carbon monoxide measurements corrected for ambient carbon monoxide in nonsmoking women during late gestation (>31 weeks). The study group included 22 women with pregnancy-induced hypertension or symptoms of preeclampsia and a control group of 20 normotensive pregnant women. RESULTS: The carbon monoxide measurements corrected for ambient carbon monoxide (mean +/- SD) were significantly lower (P <.01) in the hypertensive group than in the control group (1.17 +/- 0.35 vs 1.70 +/- 0.54 ppm). The study group had a significantly higher number of low (<1.2 ppm) end-tidal carbon monoxide measurements corrected for ambient carbon monoxide (13 [59.1%] vs 1 [5.0%]; P <.001). The end-tidal carbon monoxide measurements corrected for ambient carbon monoxide remained significantly lower in comparison with those found in the control group when the study group was divided into women with pregnancy-induced hypertension only (n = 11) and those with preeclampsia (n = 11) (1.19 +/- 0.37 ppm; P <.01; and 1.15 +/- 0.41 ppm; P <.01; respectively). CONCLUSIONS: Our findings suggest that carbon monoxide formation may be significantly lower in women with pregnancy-induced hypertension and preeclampsia. These data suggest that carbon monoxide could have a contributory role in the apparent paradox of the seemingly protective effect of smoking to decrease the risk of preeclampsia.

Pharmacokinetics of intrapericardial administration of 5-fluorouracil.

UNLABELLED: A 30-year-old patient with metastatic breast adenocarcinoma was diagnosed as having a malignant pericardial effusion. METHODS: The patient was treated with two courses of 200 mg 5-fluorouracil (5-FU) followed by 20 mg cisplatin 5 h later directly infused into the pericardial space through a catheter. The drug levels of the 5-FU were monitored during the second treatment. The half-life of 5-FU in the pericardial space was 168.6 min with a concentration of 0.113 mg/ml still detected at 5 h. The area under the curve (AUC) was estimated to be 4.739 mg h/ml. The plasma concentrations of 5-FU ranged from 0.022 to 0.04 mg/ml throughout the infusion. RESULTS: There was no significant change in the patient's blood counts or chemistry profile. She did not experience any side effects during the treatment. A pericardial window was performed 2 days later when balloon pericardiectomy was unsuccessful. The patient eventually succumbed to her disease 4 months later, but without evidence of pericardial effusion. CONCLUSIONS: We conclude that pericardial infusion of 5-FU allowed a high concentration of 5-FU to be achieved within the pericardial sac with a greatly increased half-life over that of systemic 5-FU treatment (168 min vs 6-20 min), and with little systemic toxicity.

Induction of transformation by six classes of chemical carcinogens in adult rat liver epithelial cells.

A transformation assay system using two clonal strains of adult rat liver epithelial cells is described. The carcinogens N-methyl-N'-nitro-N-nitrosoguanidine, methylmethanesulfonate, N-2-fluorenylacetamide, aflatoxin B1, benzo(a)pyrene, dimethylnitrosamine, nitrosopyrrolidine, and dimethyl-4-aminoazobenzene induced anchorage independency in one or both clonal strains, whereas noncarcinogenic analogues were inactive. In the absence of carcinogen exposure, the cell strains exhibited no spontaneous transformation to anchorage independency. These results demonstrate the reliability of anchorage independency as an in vitro end point and the specific responsiveness of adult rat liver epithelial cells to a wide range of carcinogens. Thus, the assay of transformation in adult rat liver epithelial cells is potentially useful for detection of chemical carcinogens and the study of their mechanisms of action.

The hepatocyte primary culture/DNA repair assay using mouse or hamster hepatocytes.

The hepatocyte primary culture (HPC)/DNA repair assay using rat hepatocytes was developed to identify genotoxic chemicals. Since there are species differences in susceptibility to chemical carcinogens, it was desirable to extend the assay to other species. Carcinogens and noncarcinogens from six structural classes were tested with hepatocytes from B6C3F1 mice or Syrian hamsters. In hepatocytes from both species, DNA repair was elicited by the carcinogens methyl methanesulfonate, aflatoxin B1, 2-acetylaminofluorene, benzo(a)pyrene, dimethylnitrosamine, nitrosopyrrolidine, 3'-methyl-4-dimethylaminoazobenzene, and p-dimethylaminoazobenzene. With aflatoxin B1, mouse hepatocytes required a dose of 10(-4) M for a maximum response while only 10(-6) was needed for hamster hepatocytes. All the presumed noncarcinogens, except 4-dimethylaminoazobenzene-4'-sulfonyl chloride, were negative in mouse hepatocytes. This chemical, as well as aflatoxin G2 and pyrene, which have not been tested for carcinogenicity in the hamster, were positive in hamster hepatocytes. These findings demonstrate that genotoxic chemicals can be identified by the HPC/DNA repair assay using hamster or mouse hepatocytes. Furthermore, in vivo differences in susceptibility to chemical carcinogens such as aflatoxin B1 are reflected in the in vitro assay.