Ventilatory long-term facilitation in non-snoring subjects during NREM sleep.

We hypothesized that very brief episodes of hypoxia (<1 min) would evoke long-term facilitation (LTF) in individuals free of inspiratory flow limitation (IFL). We studied 12 healthy participants who were self-reported non-snorers and confirmed the absence of IFL. We induced 15 brief episodes of hypoxia during non-REM sleep, reducing arterial oxygen saturation to 84-85%, followed by 1 min of room air. Ventilatory variables and resistance were measured during the control period, hypoxic trials, room air controls, and for 20 min following the last hypoxic episode. There was a significant increase in minute ventilation (108+/-1.3% of control, P < 0.05) and tidal volume (105+/-1.7% of control, P < 0.05) and a significant decrease in upper airway resistance (88+/-9.8% control, P < 0.05) during the recovery period. However, there were no significant changes in any variable during sham studies. We have shown for the first time that LTF can be elicited in sleeping humans free of IFL.

Misoprostol is more efficacious for labor induction than prostaglandin E2, but is it associated with more risk?

OBJECTIVE: Our purpose was to compare the efficacy and safety of misoprostol with dinoprostone (Prepidil) for labor induction. STUDY DESIGN: In a randomized, controlled trial of labor induction, patients were randomly assigned to receive either 50 microgram of intravaginal misoprostol every 4 hours or 0.5 mg of intracervical prostaglandin E2 every 6 hours. Eligibility criteria included gestation of >/=31 weeks, Bishop score <6, and fewer than 12 contractions per hour. Primary outcomes were cesarean section, induction to delivery time, oxytocin use, and fetal distress requiring delivery. RESULTS: One hundred fifty-nine women were randomly assigned to receive misoprostol (n = 81) or Prepidil (n = 78). There were no differences in the indication for induction, preinduction Bishop score, epidural use, or cesarean section rate. Mean time to delivery was significantly shorter in the misoprostol group (19 hours 50 minutes) than in the Prepidil group (28 hours 52 minutes) (P =.005). Only 58% of women in the misoprostol group required oxytocin augmentation, in comparison with 88% of women receiving Prepidil (P =.00002). However, 41% of women receiving misoprostol and 17% receiving Prepidil had late decelerations or bradycardias (P =.001), and 20% of the misoprostol group and 5% of the Prepidil group had deliveries for fetal distress (P =.05). CONCLUSIONS: Misoprostol is more efficacious than Prepidil for labor induction. However, the significantly increased incidence of abnormal fetal heart rate tracings and the trend in increased deliveries for fetal distress with misoprostol dosing of 50 microgram every 4 hours are of concern. These data suggest that either a lower dose of misoprostol or less frequent dosing of misoprostol should be considered.

The safety of early postpartum discharge: a review and critique.

OBJECTIVE: To determine the effect of early postpartum discharge (less than 48 hours after vaginal birth or 96 hours after cesarean delivery) on maternal and neonatal complications, maternal concerns, patient satisfaction, and cost savings. DATA SOURCES: We performed a MEDLINE search of English-language journals for pertinent articles published from 1966 through January 1997. We also reviewed reference lists in all the articles retrieved in the search as well as those of major obstetric texts. METHODS OF STUDY SELECTION: We included all studies describing early postpartum discharge. TABULATION, INTEGRATION, AND RESULTS: Studies included five randomized controlled trials, ten cohort studies, one case-control study, and 12 case-series reports. We classified the data using the rating system of the U.S. Preventive Services Task Force. We calculated relative risks and 95% confidence intervals for maternal and neonatal readmission and outpatient treatment after early postpartum discharge. Most studies did not show an increase in maternal or neonatal morbidity after early discharge. The five randomized controlled studies did not meet criteria for properly designed trials. Most evidence consists of cohort studies and case-series (class II-2 and III evidence) of highly selected patients with extensive supplemental antepartum and postpartum care and education. CONCLUSION: The current data do not support or condemn widespread use of early postpartum discharge in the general population (class C recommendation). Early postpartum discharge appears safe for carefully selected, consenting patients. Whether these data can be extrapolated to the general population of pregnant women remains unknown.

Does vaginal cuff closure decrease the infectious morbidity associated with abdominal hysterectomy?

BACKGROUND: Infectious morbidity after total abdominal hysterectomy includes fever (31%) and antibiotic administration (45%). Whether vaginal cuff closure reduces postoperative infectious morbidity remains unresolved. STUDY DESIGN: We reviewed the records of 172 consecutive abdominal hysterectomies for nonmalignant disease performed at an inner-city hospital. We identified potential risk factors for infectious morbidity by univariate analysis and determined adjusted odds ratios by multiple logistic regression analysis. RESULTS: The open vaginal cuff technique was associated with an increased risk of wound infection. Use of prophylactic antibiotics was associated with a decreased risk of febrile morbidity and a decreased risk of prolonged hospitalization. Body weight in the heaviest quartile was associated with increased risk of wound infection, increased risk of prolonged hospitalization, and decreased risk of postoperative vaginal cuff granulation tissue. Older age was associated with an increased risk of prolonged hospitalization. CONCLUSIONS: Closure of the vaginal cuff and use of prophylactic antibiotics at total abdominal hysterectomy were associated with decreased infectious morbidity in a high-risk population.

Elevated maternal serum alpha-fetoprotein associated with an asymptomatic tubal pregnancy at 20 weeks' gestation.

BACKGROUND: Most tubal ectopic pregnancies become symptomatic in the first trimester and rarely progress to the second trimester. Elevated maternal serum alpha-fetoprotein (MSAFP) has rarely been associated with second-trimester tubal pregnancy. We present a case of a 20-week asymptomatic tubal pregnancy identified by elevated MSAFP. CASE: An asymptomatic 22-year-old woman at 20 weeks' gestation was evaluated with a targeted fetal survey for an abnormally elevated MSAFP. The ultrasound examination revealed an extrauterine gestation. The patient was taken to exploratory laparotomy, and a total salpingectomy was performed. CONCLUSION: Although rare, a second-trimester ectopic pregnancy must be considered in the differential diagnosis of elevated MSAFP. A careful ultrasound scan should rule out an extrauterine pregnancy.

Beta-adrenergic regulation of cyclic AMP synthesis in cultured human syncytiotrophoblast.

Isolated elements of the beta-adrenergic/adenyl cyclase signal transduction system have been studied previously using purified membranes. We used cultured syncytiotrophoblast cells to identify components of this signalling system and the interactions which regulate syncytial adenyl cyclase. Generation of cyclic AMP (cAMP) was stimulated in these cells by both forskolin and isoproterenol but not by dopamine, adenosine, carbachol or prostaglandin E1. Synthesis was also stimulated by treatment with cholera toxin, indicating the involvement of the G-protein, Gs. Somatostatin inhibited isoproterenol- or forskolin-stimulated cAMP generation, an effect which could be blocked by pretreatment of the cells with pertussis toxin, demonstrating the mediation of somatostatin action by Gi. Furthermore, secretion of human chorionic gonadotrophin (hCG) was increased significantly by isoproterenol while somatostatin blocked the isoproterenol-stimulated release of hCG. These results clearly demonstrate that adenyl cyclase in syncytiotrophoblast is controlled by a stimulatory pathway operating through Gs and inhibitory pathway acting through Gi.