More or less CHAOS: case report and literature review suggesting the existence of a distinct subtype of congenital high airway obstruction syndrome.

Congenital obstruction of the upper airway (CHAOS) is a rare, usually lethal abnormality. A literature review of 36 prenatally diagnosed cases of CHAOS and the analysis of our own case suggest the existence of a distinct subtype of CHAOS, raising important implications for diagnosis and management. Serial fetal ultrasound examinations at 17-23 weeks' gestation showed hyperechoic and enlarged lungs, mediastinal shift, flattened diaphragm, polyhydramnios and apparently fluid-filled esophagus, findings interpreted as bilateral cystic adenomatoid malformation Type III. Ultrasound findings normalized around 32 weeks. The diagnosis of CHAOS was made after birth at term by direct laryngoscopy prompted by ventilatory difficulties and failed attempts at intubation. A pinhole opening posterior to the cricoid cartilage allowed the passage of an endotracheal tube. Based on observations in our case and those of five similar cases in the literature, we describe for the first time a subtype of CHAOS that is characterized by minor pharyngotracheal or laryngotracheal communications and associated with a less severe natural history and even resolution of ultrasound findings. In spite of this, a high index of awareness should be maintained because resolution of ultrasound findings does not necessarily indicate resolution of underlying pathology.

Teaching the Laufe-Piper forceps technique at cesarean delivery.

OBJECTIVE: To present a method of teaching forceps technique during cesarean delivery of breech-presenting infants using Laufe-Piper forceps and to evaluate its usefulness. STUDY DESIGN: For several years, residents at the University of Texas Medical Branch, Galveston, have learned and practiced Piper forceps technique during cesarean delivery. To assess their experience with this method, we mailed questionnaires to third- and fourth-year residents and recent graduates of the Galveston program. The same surveys were mailed to a control group of residents and recent graduates of two other programs where this teaching exercise is not practiced routinely. RESULTS: Responses were received from 32 (74%) study subjects and 63 (71%) controls. Demographic characteristics and experience with vaginal breech delivery were similar between the two groups. Respondents from the Galveston program noted greater annual use of forceps for vaginal delivery of cephalic-presenting infants (P = .012). They also rated themselves as more comfortable (P = .023) and more skilled (P = .006) with Piper forceps than controls. Of 53 respondents who had had previous experience with this teaching method, 47 noted that it provided a great or moderate educational benefit, and 36 strongly or moderately believed it gave them more confidence in using Piper forceps during vaginal breech delivery. Using multiple regression analysis, sex, overall level of experience, Piper forceps experience during vaginal delivery and overall forceps use were stronger determinants of self-rated comfort and skill than was experience with Laufe-Piper forceps during cesarean. CONCLUSION: Laufe-Piper forceps can be used for cesarean delivery of breech-presenting infants. This practice promotes confidence and skill for their use at vaginal delivery.

Uterine prolapse associated with bladder exstrophy: surgical management and subsequent pregnancy.

Congenital bladder exstrophy affects 1 in 125,000 to 250,000 females. Consisting of absence of the anterior abdominal wall with exposure of the ureteral orifices, failure of pubic symphysis fusion, and deficient anterior pelvic diaphragm musculature, bladder exstrophy is frequently associated with genital prolapse. Pregnancy may be complicated by recurrent urinary tract infections, preterm labor, mild procidentia, and malpresentation. Due to the rarity of the condition, there is a corresponding scarcity of obstetric literature regarding management during pregnancy. We report the case of a young woman with surgically repaired bladder exstrophy who developed genital prolapse. The uterus was suspended using a sacral colpopexy utilizing a Gore-Tex graft. Subsequently, the patient became pregnant and delivered a healthy male infant at 35 weeks' gestation via cesarean section (without recurrence of the genital prolapse postpartum). Sacral colpopexy to correct genital prolapse associated with bladder exstrophy may preserve fertility in young patients.

Pregnancy in bone marrow failure syndromes: Diamond-Blackfan anaemia and Shwachman-Diamond syndrome.

Pregnancy in bone marrow failure syndromes has risk to mother and fetus. There are fewer than 30 reports of cases with Diamond-Blackfan anaemia (DBA), and none with Shwachman-Diamond syndrome (SD). We report two DBA and one SD cases. One DBA mother received transfusions intra-partum, and the other only post-partum. Both required caesarean sections (C-sections) for failure of labour to progress and severe pre-eclampsia respectively. Both subsequently resumed pre-pregnancy steroid-induced control of anaemia. approximately 40% of DBA pregnancies required maternal transfusions; 25% delivered by C-section. The SD patient also had Ehlers-Danlos (ED) syndrome and urticaria pigmentosa (UP). Her blood counts were adequate until week 38, when the platelet count dropped and a C-section was performed. Pregnancy management in marrow failure disorders requires obstetricians with expertise in high-risk pregnancies, and haematologists with experience with marrow failure syndromes.

Pregnancy and renal tubular acidosis.

Renal tubular acidosis (RTA) is uncommonly encountered in pregnancy. The risk for these women to develop pregnancy-induced hypertension has not been previously described. The renal defect noted in these women, aggravated by the normal hypervolemia of pregnancy, may predispose to hypertension. Three pregnancies in two women with RTA type 1 developed persistent diastolic hypertension in the third trimester. Mild renal insufficiency was noted in each woman as defined by serum creatinine of 0.9-1.1 and 1.4-1.6 mg/dL, respectively. Vaginal delivery was achieved in each without complications. Blood pressures returned to normal following each pregnancy. Pregnancy-induced hypertension developed in each of three pregnancies in two patients with RTA type 1. The risk for these women to develop pregnancy-induced hypertension may be associated with the higher reported risk in women with underlying renal disease.

Forceps and vacuum delivery: expectations of residency and fellowship training program directors.

The objective of this study is to compare current forceps training practices in North American obstetrical residency training programs with that in maternal-fetal medicine fellowship programs. We sent a survey to all obstetrics and gynecology residency training programs and to all maternal-fetal medicine fellowship programs in North America. After sending out 354 questionnaires, 219 were returned for a response rate of 62%. The response rate for fellowship programs (52 of 59; 88%) was significantly greater than that of residency training programs (167 of 295; 56.6%) (p < 0.05). All fellowship training programs were using the 1988 ACOG forceps classification system, as were 98% of the residency training programs. Eighty-five percent of fellowship directors and 80% of residency directors felt the same system should be used for vacuum deliveries. All residency and fellowship directors expected proficiency with both instruments for outlet deliveries. For low deliveries requiring < or =45 degrees of rotation, at least 92% expected proficiency with both instruments. For low-forceps deliveries with >45 degrees of rotation, 82% of fellowship directors and 80% of residency directors expected proficiency. For low-vacuum deliveries with >45 degrees of rotation, 80% of fellowship directors and 76% of residency directors expected proficiency. Significantly more fellowship directors expected midforceps proficiency (47%) than did residency program directors (38%) (p < 0.05). Midvacuum proficiency was expected by 73% of fellowship directors and 69% of residency directors. The ACOG 1988 forceps classification system has now achieved wide acceptance and is taught by both residency and fellowship program directors. Most program directors favor using the same classification system for vacuum extraction deliveries. In general, the expectations of the residency program directors mirror those of maternal-fetal medicine fellowship directors. While outlet and low operations with < or =45 degrees of rotation are taught and proficiency is expected, most programs no longer expect proficiency in midforceps delivery, but do expect proficiency in midvacuum delivery. Proficiency in low operations with rotations < or =45 degrees is still expected.

Electronic fetal monitoring. Are we meeting documentation standards?

OBJECTIVE: To test whether fetal heart rate documentation requirements for high-risk pregnancies are too stringent to achieve compliance, especially during the second stage of labor. STUDY DESIGN: Random retrospective chart and monitor strip review of deliveries occurring one year earlier were reviewed. Thirty-four low-risk and 34 high-risk pregnancies were selected and assessed for compliance with nationally accepted documentation guidelines. RESULTS: All monitor strips and charts were successfully retrieved from medical records. Charted documentation of the strips met national requirements in the active phase of the first stage of labor in 97% of cases, as did documentation during the second stage. For high-risk pregnancies, compliance during the active phase of the first stage of labor was 65% as compared to 35% in the second stage. All infants had normal five-minute Apgar scores, and none had umbilical arterial acidemia. CONCLUSION: Given current resources, we cannot reliably meet established documentation standards for high-risk pregnancies. Such overly stringent documentation standards pose a significant risk in cases going to litigation. A standard should be developed that is based on outcome data.

Acute gastric aspiration: prevention and treatment.

Pulmonary aspiration of gastric contents is a leading cause of maternal morbidity and mortality for patients during labor. The risk is increased in those women who require obstetric surgery and general anesthesia. Furthermore, gastric aspiration is believed to be largely preventable. Care providers can reduce the risk by limiting oral intake during labor and assuming that all parturients have a full stomach. Conduction anesthesia should be encouraged over general anesthesia. Having a skilled anesthesiologist available is optimal. Prophylactic use of antacids, H2 receptor antagonists, and/or the use of dopamine antagonists should be administered before obstetric surgery to raise the pH and decrease the volume of gastric contents. Should aspiration occur, prompt recognition, treatment, and monitoring will improve outcome.

Inadequate weight gain among pregnant adolescents: risk factors and relationship to infant birth weight.

OBJECTIVE: Our purpose was to identify behavioral markers for inadequate weight gain (< 20 pounds) during pregnancy among adolescents < 18 years old. STUDY DESIGN: A total of 337 adolescents who were delivered of a term infant at our institution between March 10, 1992, and November 28, 1994 participated in this study. A comprehensive structured interview conducted at the first prenatal visit elicited demographic information and behavioral risk factors. Maternal weights, reproductive history, evidence of sexually transmitted disease, and infant birth weight were extracted from medical records. Logistic regression and chi 2 analyses compared characteristics and infant birth weights between those who gained < 20 pounds with those who gained > or = 20 pounds. RESULTS: A total of 11.6% (39/337) of the total sample gained < 20 pounds during the pregnancy. Adolescents who gained < 20 pounds compared with > or = 20 pounds were delivered of significantly lighter (2942 gm vs 3392 gm) infants and were more likely to be delivered of infants weighing < 2500 gm (13% vs < 1%). Stepwise logistic regression revealed that adolescents who were battered (odds ratio 5.3) or had a sexually transmitted disease (odds ratio 2.3) or an unplanned pregnancy (odds ratio 8.1) were at increased risk for insufficient weight gain during pregnancy. CONCLUSION: Our data suggest that behavioral risk factors are important in the identification of adolescents at greatest risk for inadequate weight gain. Early identification during pregnancy is essential to modify nutritional practices and thus minimize poor obstetric outcomes.

PIP: Among adolescents, maternal weight gain is considered the most important determinant of infant birth weight. To assist obstetricians in identifying adolescents at highest risk of inadequate weight gain early in the pregnancy, a study was conducted of 337 US adolescents under 18 years of age who delivered a full-term infant at the University of Texas Medical Branch (Galveston) in 1992-94. 39 (11.6%) of these adolescents gained under 20 pounds during pregnancy. Infants of these adolescents weighed significantly less at birth (average, 2942 g) than those of adolescents who gained 20 or more pounds (average, 3392 g). Moreover, the low-birth-weight (2500 g) rate was 13% in the former group compared with less than 1% in the adequate weight gain group. Gravidity, parity, school enrollment, marital status, employment status, or poverty level were not associated with maternal weight gain. Stepwise logistic regression identified the following risk factors for insufficient weight gain during pregnancy: physical assault/battering during pregnancy (odds ratio (OR), 5.3), a sexually transmitted disease during pregnancy (OR, 2.3), and an unplanned pregnancy (OR, 8.1). History taking during adolescent pregnancy should be expanded to include assessment of these factors.

Tissue inhibitor of metalloproteinase-1 and tissue inhibitor of metalloproteinase-2 expression in human amnion mesenchymal and epithelial cells.

OBJECTIVE: This study was conducted to define the cellular site of expression of tissue inhibitor of metalloproteinase-1 and tissue inhibitor of metalloproteinase-2 in human amnion by an evaluation of the levels of messenger ribonucleic acids in separated amnion epithelial and mesenchymal cells and to ascertain whether amnion epithelial and mesenchymal cells maintained in culture continue to express tissue inhibitor of metalloproteinase messenger ribonucleic acids. STUDY DESIGN: Human placentas and fetal membranes were obtained immediately after delivery. Amnion tissue was separated from chorion laeve and either frozen immediately (-80 degrees C) or processed by differential enzymatic treatment to separate the epithelial and mesenchymal cells, which were frozen (-80 degrees C) or else plated and maintained in monolayer culture. The levels of tissue inhibitor of metalloproteinase types 1 and 2 messenger ribonucleic acid were evaluated by Northern analyses of total ribonucleic acid extracted from amnion tissue, freshly separated epithelial and mesenchymal cells, and epithelial and mesenchymal cells in monolayer culture. RESULTS: Tissue inhibitor of metalloproteinase types 1 and 2 messenger ribonucleic acids were detected by Northern analysis in freshly isolated amnion tissues from midtrimester and term pregnancies. The major species of tissue inhibitor of metalloproteinase-1 messenger ribonucleic acid was 0.9 kb in length; a minor species of approximately 3.5 kb also was present. Tissue inhibitor of metalloproteinase-2 messenger ribonucleic acids of 3.5 and 1.0 kb and of similar intensity were also detected. The levels of type 1 messenger ribonucleic acid were not different in amnion tissues obtained at term or during the midtrimester of pregnancy. The levels of tissue inhibitor of metalloproteinase type 2 messenger ribonucleic acids in amnion tissue most commonly were greater at term than in tissues obtained during the midtrimester. The level of type 1 messenger ribonucleic acid in mesenchymal cells was appreciably greater than that in epithelial cells, and this difference was maintained during culture of these cells. The level of type 2 messenger ribonucleic acid was similar in both cell types and was maintained during culture. The levels of type 1 or 2 messenger ribonucleic acids were not affected by treatment of amnion epithelial or mesenchymal cells in culture with a variety of test agents, including steroid hormones, cytokines, and growth factors. CONCLUSION: The amnion mesenchymal cells are the primary source of tissue inhibitor of metalloproteinase-1 in human amnion, whereas both cell types have the potential to produce tissue inhibitor of metalloproteinase-2.

Operative vaginal delivery--year 2000.

Literature review was performed to analyze and define the current state of operative vaginal delivery. On the basis of published data, it is concluded that outlet and low forceps deliveries with < or = 45 degrees of rotation are effective and safe for both mother and baby. The greatest risk to mother or fetus occurs with operations performed at the 0 or +1 station or those involving rotations > 45 degrees. It is likely that operative deliveries involving > 45 degrees of rotation will be abandoned in the future. It is further recommended that The American College of Obstetricians and Gynecologists 1988 forceps classification system be adopted for deliveries by vacuum extractors.

Asthma treatment in pregnancy: a randomized controlled study.

OBJECTIVE: Our purpose was to study the effect of inhaled corticosteroids on asthma exacerbations in pregnancy. STUDY DESIGN: We prospectively studied 84 pregnant women with 105 asthma exacerbations. Women were hospitalized if the forced expiratory volume in 1 second was < 70% after sequential bronchodilator therapy. They were randomly assigned to receive either intravenous aminophylline and inhaled beta 2-adrenergic receptor agonist or intravenous methylprednisolone and a beta 2-adrenergic receptor agonist. At discharge women were randomly assigned to receive either inhaled beclomethasone, beta 2-adrenergic receptor agonist, and an oral corticosteroid taper or a beta 2-adrenergic receptor agonist and a corticosteroid taper. RESULTS: Sixty-five (62%) of 105 women with exacerbation required hospitalization. Aminophylline did not shorten response time or decrease hospital stay. Readmission rate was decreased by 55% in women given inhaled beclomethasone (33% vs 12%, p < 0.05, odds ratio 3.63, 95% confidence interval 1.01 to 13.08). Pregnancy-induced hypertension and cesarean delivery were increased over those of the general population. CONCLUSIONS: Intravenous aminophylline offers no therapeutic advantages. Continuous inhaled corticosteroids reduced the need for subsequent admissions.

An unusual fetal complication of traumatic uterine rupture.

Rupture of the gravid uterus is reported in less than one percent of women involved in motor vehicle accidents. A 22-year-old nulliparous woman at 22 weeks gestation was involved in a motor vehicle accident. Evaluation revealed a uterine rupture with complete expulsion of placenta and decapitated fetus. Prompt surgical intervention and control of hemorrhage allowed preservation of fertility.