Biomedical subjects

G R Markenson

Publications and source records attributed to G R Markenson.

10 recordsLinked to original sources

PubMed2001

Pregnancy complicated by chronic spinal cord injury and history of autonomic hyperreflexia.

BACKGROUND: Women with spinal cord injuries are at risk for autonomic hyperreflexia during labor. CASE: A 36-year-old woman, gravida 4, para 2, abortus 1, with a spinal cord injury and a positive antibody screen result had had a previous pregnancy complicated by autonomic hyperreflexia during labor. Autonomic hyperreflexia did not occur during serial amniocenteses and fetal transfusions for isoimmunization or intrapartum. CONCLUSION: Intrauterine procedures and vaginal delivery were accomplished without autonomic hyperreflexia in this pregnancy. Intrauterine procedures and vaginal delivery might be done safely in women with histories of autonomic hyperreflexia.

Adult↗

PubMed2001

Anesthetic management of the exit (ex utero intrapartum treatment) procedure.

The EXIT (ex utero intrapartum treatment) procedure is used to maintain fetal-placental circulation during partial delivery of a fetus with a potentially life-threatening upper airway obstruction. We performed the EXIT procedure on a fetus with a large intra-oral cyst. Sevoflurane was used as the anesthetic because of its rapid titratability. Sevoflurane provided excellent maternal and fetal anesthesia. Modifications to previously described monitoring techniques for the EXIT procedure were also used.

Adult↗

PubMed2000

Epidural analgesia for cephalic version: a randomized trial.

OBJECTIVE: To determine if epidural analgesia improves the success rate of external cephalic version. METHODS: Women with singleton fetuses in breech or transverse presentation of at least 37 weeks' gestation were offered enrollment in a randomized trial. Inclusion criteria included maternal age of 18 years or older, nonvertex presentation confirmed by ultrasound, intact membranes, reactive fetal nonstress test, and estimated fetal weight (EFW) between 2000 and 4000 g. Women in the epidural group had lumbar epidural catheters inserted, through which 2% lidocaine and 100 microg of fentanyl were infused. External cephalic version attempts were done with ultrasound guidance in a standard fashion for both groups. The primary outcome variable was the successful version of the fetus to a cephalic presentation. RESULTS: There were no statistically significant differences between groups in gestation at time of procedure, placental location, fetal lie, gravity, parity, EFW, or amniotic fluid index. External cephalic version was successful in 32 of 54 women (59%) with epidural anesthesia compared with 18 of 54 (33%) with no anesthesia (relative risk [RR] 1.8, 95% confidence interval [CI] 1.2, 2.8, P <.05). Vaginal delivery occurred in 29 of 54 women (54%) in the epidural group and 16 of 54 women (30%) in the control group (RR 1.9, 95% CI 1.2, 2.9, P <.05). CONCLUSION: Epidural analgesia increased the success rate of external cephalic version and the likelihood of subsequent vaginal delivery.

Adult↗

PubMed2000

Myomectomy during early pregnancy.

Abdominal pain during early pregnancy may be caused by leiomyoma of the uterus. Inconsistency of uterine size and gestational dates in a pregnant patient with acute abdominal pain may be the first sign of leiomyoma. This 31-year-old primigravida presented with progressively worsening lower abdominal pain at 12 weeks gestational age. Ultrasonography and magnetic resonance imaging demonstrated a large fundal heterogeneous mass and an intrauterine gestation compatible with her menstrual dates. Exploratory surgery and myomectomy confirmed a large leiomyoma showing benign degenerative changes. The operative procedure was successful, and the pregnancy progressed normally. An elective cesarean section was performed at 37 weeks gestation after confirming fetal maturity by amniocentesis and serial ultrasonography. Abdominal pain in a pregnant patient with leiomyoma uteri may be attributable to degenerative changes in the myoma. Surgical intervention during pregnancy is occasionally necessary in uncommon cases of intractable pain.

Abdominal Pain↗

PubMed1998

Parvovirus B19 infections in pregnancy.

Parvovirus B19 is the viral agent that causes the childhood exanthum erythema infectiosum, or fifth disease. Approximately 50% of pregnant women are seropositive for this agent and thus immune to primary infection. However, acute infection may develop in seronegative pregnant women exposed to B19. Acute B19 infections during pregnancy have been associated with miscarriage and hydrops fetalis. This latter condition is amenable to fetal therapy via intrauterine transfusion.

Anemia↗

PubMed1997

The fetoplacental pressor effects of low-dose acetylsalicylic acid and angiotensin II in the ex vivo cotyledon model.

OBJECTIVE: Our purpose was to investigate perfusion pressure changes ex vivo induced by angiotensin II on fetoplacental vasculature pretreated with low-dose acetylsalicylic acid. STUDY DESIGN: Two cotyledons from each of 12 placentas were perfused. The intervillous space of one cotyledon was infused with acetylsalicylic acid (5 x 10(-5) mol/L) similar to the serum concentration of women receiving daily low-dose aspirin therapy (60 to 81 mg). The control cotyledon was infused with an equivalent amount of normal saline solution. Two doses of angiotensin II, 1 x 10(-11.5) and 1 x 10(-10) moles, were injected as boluses into the chorionic arteries of each cotyledon. A 3 x 10(-7) mole dose of angiotensin II was also injected into the intervillous space. Statistical analysis was performed with analysis of variance, and results are expressed as mean pressure change in millimeters of mercury +/- SEM. RESULTS: Perfusion pressure response did not vary between cotyledons pretreated with acetylsalicylic acid and control cotyledons when 3 x 10(-7) moles of angiotensin II was injected into the intervillous space (8.0 +/- 1.9 mm Hg vs 9.8 +/- 1.6 mm Hg, p = 0.59). There were no differences between cotyledons in pressure response to 1 x 10(-11.5) moles of angiotensin II injected into the fetal circuit (5.9 +/- 0.8 mm Hg vs 6.7 +/- 0.9 mm Hg, p = 0.51). However, in the cotyledons pretreated with acetylsalicylic acid there was a decrease in the pressor response to 1 x 10(-10) moles of angiotensin II (14.1 +/- 1.4 mm Hg vs 21.5 +/- 3.3 mm Hg, p = 0.05). CONCLUSIONS: Low-dose aspirin infused into the intervillous space decreases vasoconstriction elicited by angiotensin II in the fetoplacental compartment. This suggests that maternal low-dose aspirin therapy has effects in the fetoplacental circulation in addition to its effects in the maternal circulation.

Angiotensin II↗

PubMed1997

The use of the polymerase chain reaction to detect bacteria in amniotic fluid in pregnancies complicated by preterm labor.

OBJECTIVES: The purpose of this investigation was to determine the feasibility of using the polymerase chain reaction to detect bacteria in amniotic fluid and to compare pregnancy outcomes in subsets of women categorized by amniotic fluid culture, polymerase chain reaction, and interleukin-6 findings. STUDY DESIGN: Amniotic fluid from 54 pregnancies with preterm labor and no clinical evidence of intraamniotic infection was evaluated with use of the polymerase chain reaction, interleukin-6, and bacterial culture. Gestational age, newborn weight, and time between amniocentesis and delivery were compared between subsets of women categorized by these tests. RESULTS: With use of the polymerase chain reaction <100 bacteria per milliliter could be detected in amniotic fluid. A total of 55.5% of the amniotic fluid samples were polymerase chain reaction positive, whereas 9.2% of culture results were positive. Birth weights and gestational age at delivery were less and time from amniocentesis to delivery was shorter in the polymerase chain reaction-positive group (p < 0.05). Nine samples (15%) had elevated interleukin-6 concentrations; of these, six were polymerase chain reaction positive. CONCLUSIONS: The polymerase chain reaction is a sensitive means of detecting bacteria in amniotic fluid. These results provide further evidence of an association between preterm delivery and intraamniotic infection. Not all amniotic fluid samples with elevated interleukin-6 levels have bacteria detectable by the polymerase chain reaction. We anticipate that the polymerase chain reaction will provide another avenue for the detection of bacteria in amniotic fluid.

Adult↗

PubMed1996

The accuracy of late antenatal screening cultures in predicting genital group B streptococcal colonization at delivery.

OBJECTIVE: To determine the accuracy of late antenatal anogenital cultures in predicting group B streptococcal colonization at delivery. METHODS: Swabs of the vagina and rectum were obtained from 826 women during routine prenatal visits at approximately 35-36 weeks' estimated gestation. The same women were recultured at admission for delivery. Swabs were cultured in broth media. Test performance indices were calculated using culture status at the time of delivery as the reference. Based on the sensitivity and specificity of antenatal cultures derived from analysis of this study population, we estimated predictive values of late antenatal cultures for a range of group B streptococcal carriage rates. RESULTS: Group B streptococci were identified in specimens from 219 of 826 women (26.5%). The sensitivity of late antenatal cultures for identifying colonization status at delivery was 87% (95% confidence interval [95% CI] 83-92). Specificity was 96% (95% CI 95-98). Positive predictive value was 87% (95% CI 83-92), and negative predictive value was 96% (95% CI 95-98). Test performance was similar from 1-5 weeks before delivery, but declined when 6 or more weeks had elapsed between the antenatal culture and delivery. Among patients cultured 6 or more weeks before delivery, sensitivity was only 43%, specificity 85%, and positive and negative predictive values were 50 and 81%, respectively. We estimated positive and negative predictive values of 85 and 97% for a colonization rate of 20%, and 79 and 98% for a colonization rate of 15%. CONCLUSION: Anogenital cultures in broth media obtained during the late antenatal period are accurate in predicting group B streptococcal colonization status at delivery in term parturients, and they perform significantly (P < .01) better than cultures collected 6 or more weeks before delivery.

Adult↗

PubMed1995

The effects of atrial natriuretic factor and angiotensin II on fetal-placental perfusion pressure in the ex vivo cotyledon model.

OBJECTIVE: Our purpose was to investigate pressure changes induced by angiotensin II on placental vasculature pretreated with atrial natriuretic factor. STUDY DESIGN: A dual-perfused cotyledon model was used. Two cotyledons from each placenta were perfused. One cotyledon was infused with atrial natriuretic factor for 30 minutes while the other received an equal volume of saline solution. Three atrial natriuretic factor concentrations were studied: 50 pg/ml, 150 pg/ml, and 15 ng/ml. Both cotyledons received injections of angiotensin II, at the following doses: 1 x 10(-11.5), 1 x 10(-11), 1 x 10(-10.5), and 1 x 10(-10) mol. RESULTS: Cotyledons subjected to 50 pg/ml and 150 pg/ml concentrations of atrial natriuretic factor did not differ in pressure responses to angiotensin II, compared with the saline-infused cotyledons (p > 0.05). The 15 ng/ml concentration of atrial natriuretic factor, however, decreased the pressor response of angiotensin II (p < 0.034). CONCLUSIONS: Atrial natriuretic factor decreases vasoconstriction caused by angiotensin II. However, this was seen only at a supraphysiologic concentration. No effect was noted at normal fetal concentrations of atrial natriuretic factor.

Angiotensin II↗

PubMed1993

Discharge against medical advice in an obstetric unit.

Obstetricians have increasingly petitioned courts for orders sanctioning treatment refused by pregnant patients. To speculate on the potential role of forced detention, we reviewed the clinical records of 39 obstetric patients who were discharged against medical advice (AMA) with several diagnoses: preterm labor (27), medical complications of pregnancy (9) and trauma (3). These patients were matched for chronologic age, gestational age and clinical examination at the time of admission and compared to a group of compliant patients who accepted and followed the treatment plan for hospitalization. No perinatal morbidity and/or mortality or other adverse outcome could be documented in the AMA group despite their refusal to continue undergoing admission and therapy. No difference could be demonstrated between the AMA group and the compliant group for obstetric complications, gestational age at delivery, newborn weight and percentage of appropriate-weight-for-gestational-age infants. These data suggest that failure to comply with major obstetric recommendations and hospitalization in these clinical settings might not adversely influence perinatal outcome.

Female↗