Nurse Staffing in Neonatal Intensive Care Units in the United States.

The neonatal intensive care unit (NICU) is a setting with high nurse-to-patient ratios. Little is known about the factors that determine nurse workload and assignment. The goals of this study were to (1) develop a measure of NICU infant acuity; (2) describe the acuity distribution of NICU infants; (3) describe the nurse/infant ratio at each acuity level, and examine the factors other than acuity, including nurse qualifications and the availability of physicians and other providers, that determined staffing ratios; and (4) explore whether nurse qualifications were related to the acuity of assigned infants. In a two-stage cohort study, data were collected in 104 NICUs in 2008 by nurse survey (6,038 nurses and 15,191 infants assigned to them) and administrators reported on unit-level staffing of non-nurse providers; in a subset of 70 NICUs in 2009-2010, census data were collected on four selected shifts (3,871 nurses and 9,276 infants assigned to them). Most NICU infants (62%) were low-acuity (Levels 1 and 2); 12% of infants were high-acuity (Levels 4 and 5). The nurse-to-infant ratio ranged from 0.33 for the lowest-acuity infants to 0.95 for the highest-acuity infants. The staffing ratio was significantly related to the acuity of assigned infants but not to nurse education, experience, certification, or availability of other providers. There was a significant but small difference in the percentage of high-acuity (Levels 4 and 5) infants assigned to nurses with specialty certification (15% vs. 12% for nurses without certification). These staffing patterns may not optimize patient outcomes in this highly intensive pediatric care setting.

Effect of perceived stress on cytokine production in healthy college students.

Chronic psychological stress impairs antibody synthesis following influenza vaccination. Chronic stress also increases circulating levels of proinflammatory cytokines and glucocorticoids in elders and caregivers, which can impair antibody synthesis. The purpose of this study was to determine whether psychological stress increases ex vivo cytokine production or decreases glucocorticoid sensitivity (GCS) of peripheral blood leukocytes from healthy college students. A convenience sample of Reserve Officer Training Corps (ROTC) students completed the Perceived Stress Scale (PSS). Whole blood was incubated in the presence of influenza vaccine and dexamethasone to evaluate production of interleukin-6 (IL-6), interleukin-1-beta (IL-1ß), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ). Multiple regression models controlling for age, gender, and grade point average revealed a negative relationship between PSS and GCS for vaccine-stimulated production of IL-1ß, IL-6, and TNF-α. These data increase our understanding of the complex relationship between chronic stress and immune function.

Birth outcomes following self-inflicted poisoning during pregnancy, California, 2000 to 2004.

OBJECTIVE: To describe birth outcomes following intentional acute poisoning during pregnancy. SETTING: California Linked Vital Statistics-Patient Discharge Database, 2000 to 2004. PARTICIPANTS: Pregnant women age 15 to 44, who had a singleton live birth or fetal death that occurred between gestational ages 20 and 42 weeks who were discharged from the hospital for an intentional poisoning were compared to pregnant women discharged from the hospital for any nonpoisoning diagnosis. Intentional acute poisoning hospital discharges were identifed by the presence of an ICD-9-CM E-Codes E950-E952 (suicide, attempted suicide and self-inflicted injuries specified as intentional.) METHODS: Through a retrospective cohort design, birth outcomes including low birth weight; preterm birth; fetal, neonatal, and infant death; and congenital anomalies were identified by the presence of ICD-9-CM diagnosis codes or by notation in the dataset. RESULTS: There were 430 hospital discharges for an intentional poisoning during pregnancy documented in the dataset (rate=25.87/100,000 person years). The rate of intentional poisoning was greatest in the first weeks of gestation and declined with increasing gestational age. Analgesics, antipyretics, and antirheumatics were most commonly implicated. Adverse birth outcomes associated with intentional poisoning included preterm birth (odds ratio [OR]=1.34; 95% Confidence Interval [CI] [1.01, 1.77]), low birth weight (OR=1.49; 95% CI [1.04, 2.12]), and circulatory system congenital anomalies (OR=2.17; 95% CI [1.02, 4.59]). CONCLUSION: Intentional acute poisoning during pregnancy was associated with several adverse birth outcomes; however, these relationships may be confounded by concomitant maternal substance abuse.

The Role of Obesity in Preeclampsia.

The incidence of obesity is increasing at an alarming rate. There is compelling evidence that obesity increases the risk of preeclampsia about 3-fold, and in developed countries is the leading attributable risk for the disorder. In this presentation we explore this relationship and propose targets for future studies guided by the much more extensively studied relationship of obesity to cardiovascular disease. We further address the hypothesis that asymmetric dimethyl arginine (ADMA), an endogenous inhibitor of nitric oxide synthase, may be one convergence point for the mechanism by which obesity increases the risk of preeclampsia. We conclude with consideration of the clinical implications of this information.

The epidemiology of acute poisonings in women of reproductive age and during pregnancy, California, 2000-2004.

The aims of this study were to describe and compare the epidemiology of acute poisoning hospital discharges in women of reproductive age and during pregnancy (aged between 15 and 44) to include the incidence rate, risk factors, substances involved, rates of intentional versus unintentional poisonings, and in pregnant women, distribution over trimesters. Through a cohort study design, the California patient discharge dataset and linked vital statistics-patient discharge database were used to identify cases of acute poisoning hospital discharges from 2000 to 2004 among women of reproductive age and among pregnant women. Odds ratios (OR) were calculated to identify risk factors using logistic regression. Of 4,436,019 hospital discharges in women of reproductive age, 1% were for an acute poisoning (115.3/100,000 person-years). There were 2,285,540 deliveries and 833 hospital discharges for an acute poisoning during pregnancy (48.6/100,000 person-years). Pregnancy was associated with a lower risk of acute poisoning (OR = 0.89, P = 0.0007). Poisonings were greatest among young black women regardless of pregnancy status and among those with substance abuse or mental health problems. Analgesic and psychiatric medications were most commonly implicated. The majority of poisonings among women of reproductive age (69.6%) and among pregnant women (61.6%) were self-inflicted. Efforts to reduce acute poisonings among women of reproductive age should include education regarding the use of over-the-counter medications and interventions to reduce self-inflicted harm.

"Active labor" duration and dilation rates among low-risk, nulliparous women with spontaneous labor onset: a systematic review.

INTRODUCTION: Laboring women are often admitted to labor units under criteria that are commonly associated with the onset of active-phase labor (i.e., cervical dilatation of 3-5 cm in the presence of regular contractions). Beginning with these criteria through complete dilatation, this systematic review describes labor duration and cervical dilation rates among low-risk, nulliparous women with spontaneous labor onset. METHODS: Studies published in English (between 1990 and 2008) were identified via MEDLINE and CINAHL searches. Data were abstracted and weighted "active labor" durations (i.e., from 3-5 cm through complete dilatation) and linear dilation rates were calculated. RESULTS: Eighteen studies (n = 7009) reported mean "active labor" duration. The weighted mean duration was 6.0 hours, and the calculated dilation rate was 1.2 cm per hour. These findings closely parallel those found at the median. At the statistical limits, the weighted "active labor" duration was 13.4 hours (mean + 2 standard deviations) and the dilation rate was 0.6 cm per hour (mean - 2 standard deviations). DISCUSSION: These findings indicate that nulliparous women with spontaneous labor onset have longer "active" labors and therefore slower dilation rates than are traditionally associated with active labor when commonly used criteria are applied as the starting point. Revision of existing active labor expectations and/or criteria used to prospectively identify active phase onset is warranted.

What is the slowest-yet-normal cervical dilation rate among nulliparous women with spontaneous labor onset?

OBJECTIVE: To integrate research literature that has provided insights into the cervical dilation rate that may best describe the slowest-yet-normal dilation rate among nulliparous women when beginning with criteria commonly associated with active labor onset. DATA SOURCES: A literature search from 1950 through 2008 was conducted using the Medline electronic database, reference lists from identified articles, and other key references. STUDY SELECTION: Research reports written in English with a focus on the cervical dilation and/or labor duration of low-risk, nulliparous women with spontaneous labor onset. DATA EXTRACTION: Classic and contemporary research literature was reviewed and organized under the following subheadings: Friedman Studies, Partograph Studies, Active Management of Labor Studies, Additional Studies. DATA SYNTHESIS: An integrative review of the literature approximated the slowest-yet-normal cervical dilation rate for nulliparous women when beginning with criteria commonly associated with active labor. CONCLUSIONS: The slowest-yet-normal linear dilation rate approximates 0.5 cm/hour for low-risk, nulliparous women with spontaneous labor onset when starting at dilatations traditionally associated with active labor onset. However, this linear rate must be evaluated judiciously in light of the physiological acceleration of dilation that occurs during typical labor. Given this, cervical dilation for this population is likely slower than 0.5 cm/hour in earlier active labor and faster in more advanced active labor. Faster dilation expectations (e.g., 1 cm/hour) likely contribute to an overdiagnosis of dystocia ("slow, abnormal progression of labor") in contemporary practice and, subsequently, to an overuse of interventions aimed at accelerating labor progress.

Is difficult childbirth related to postpartum maternal outcomes in the early postpartum period?

Unplanned, adverse events during labor or delivery may generate a negative response during the early postpartum period, resulting in disruption of usual functioning and mood. High levels of maternal depressive symptoms are associated with parenting, infant attachment, behavioral problems and cognition (Beck 2002). The purpose of this study was to examine the relationship of adverse events in labor or delivery and depressive symptoms, functional status and infant care at 2-weeks postpartum. The secondary aim was to explore the role of social support as a possible moderator in the relationship between adverse birth events and maternal outcomes. A secondary analysis of data (n = 123) was performed using data collected in a prospective, observational study examining the effects of antidepressant use during pregnancy. Adverse events did not significantly predict depressive symptoms (odds ratio = 1.34, p = .536), functional status (R(2) change = .001, p = .66), or infant care (R(2) change = .004, p = .48) at 2-weeks postpartum when controlling for depression during pregnancy, antidepressant use at delivery, education level, age, and parity. Social support had significant effects on depressive symptoms (p = .02), functional status (p = .014), and infant care (p < .001) but did not moderate the effect of adverse events when predicting depressive symptoms (odds ratio = 1.01, p = .045), functional status (R(2) change = .009, p = .056) and infant care (R(2) change < .001, p = .92). Adverse events did not predict maternal outcomes at 2-weeks postpartum. Social support was related to depressive symptoms, functional status and infant care, but did not moderate the effects of adverse events.

A history of infant feeding.

The historical evolution of infant feeding includes wet nursing, the feeding bottle, and formula use. Before the invention of bottles and formula, wet nursing was the safest and most common alternative to the natural mother's breastmilk. Society's negative view of wet nursing, combined with improvements of the feeding bottle, the availability of animal's milk, and advances in formula development, gradually led to the substitution of artificial feeding for wet nursing. In addition, the advertising and safety of formula products increased their popularity and use among society. Currently, infant formula-feeding is widely practiced in the United States and appears to contribute to the development of several common childhood illnesses, including atopy, diabetes mellitus, and childhood obesity.

A comparison of circulating TNF-alpha in obese and lean women with and without preeclampsia.

OBJECTIVES: We hypothesized that TNF-alpha would be higher in obese versus lean women with preeclampsia. METHODS: Total plasma TNF-alpha was measured in a nested case-control study of 123 nulliparous lean and obese control women and women with preeclampsia. RESULTS: Adjusted mean TNF-alpha concentrations were 0.97 +/- 0.11 (pg/mL +/- SEM) in lean controls, 1.01 +/- 0.10 in obese controls, 1.43 +/- 0.11 in lean women with preeclampsia and 1.16 +/- 0.11 in obese women with preeclampsia. Pregnancy outcome was the single predictor of TNF-alpha concentration in the general linear regression model (p = 0.04). CONCLUSION: TNF-alpha concentration was higher in preeclampsia compared with control subjects. Obesity was not associated with higher TNF-alpha concentrations in either preeclampsia or control subjects.

Predictors of intention to practice safer sex among Korean college students.

This study examined the efficacy of the Theory of Planned Behavior (TpB) among Korean college students on intentions of condom use. A cross-sectional, correlational design was conducted with an exploratory survey method. Young men and women aged 18-25 were recruited from a university in Seoul, Korea using a flyer and self-referral. Students completed a background and sexual behavior questionnaire, a parent-adolescent communication scale, and instruments derived from the TpB. Age, parent-adolescent communication, and perceived risk of sexual behavior were added to the model as potential determinants of intention of condom use. All the TpB components significantly predicted intention of condom use for young men, but only condom attitude and condom efficacy significantly predicted intention of condom use for young women. Age and quality of parent-adolescent communication indirectly affected the intention of condom use; however, perceived risk of sexual behavior did not predict intention of condom use, nor was it affected by age. Older students had a higher condom efficacy and a higher perceived peer norm of condom use. The quality of parent-adolescent communication significantly predicted a higher condom efficacy for young men, but not women.

Maternal leptin across pregnancy in women with small-for-gestational-age infants.

OBJECTIVE: We hypothesized that women with small-for-gestational-age (SGA) neonates would have lower concentrations of leptin compared to women with appropriately grown infants (AGA). STUDY DESIGN: This is a nested case-control study of normotensive nulliparous women. Cases (n = 28) delivered SGA < 10 percentile and controls (n = 77) delivered AGA. Maternal plasma leptin concentrations were compared at 18, 28, and 40 weeks' gestation via repeated measures. RESULTS: Maternal leptin concentrations at 18 weeks were correlated with prepregnancy BMI (r = 0.69, P < .0001) and early pregnancy waist circumference (r = 0.59, P < .0001). After adjustment for maternal body composition, leptin was lower across pregnancy in women with SGA compared to AGA neonates (13.6 vs 15.2 ng/mL at 18 weeks; 13.6 vs 17.3 ng/mL at 28 weeks; 16.6 vs 20.7 ng/mL at 40 weeks; P = .04). CONCLUSION: Maternal leptin was correlated with maternal adiposity; however, after adjustment for body composition, leptin was lower across pregnancy in women with SGA.

Evaluating the Theory of Planned Behavior to explain intention to engage in premarital sex amongst Korean college students: a questionnaire survey.

BACKGROUND: To reduce risky adolescent sexual behavior, education programs must be tailored to specific cultures and stage of adolescence. OBJECTIVES: This study describes the self-reported sexual behavior of Korean college students and examines the efficiency of the Theory of Planned Behavior (TpB) in explaining intention of engaging in premarital sex in order to provide insights for a potential sex education program designed to reduce risky sexual behavior. DESIGN: A cross-sectional, correlational design using an exploratory survey method was used. PARTICIPANTS: Participants were recruited from a university in Korea with a flyer posted at the entrance of the student health service center, and self-referral in 2004. Male and female unmarried college students aged 18 to 25 were included. Foreign students and students with visible physical problems were excluded. Three hundred and twenty of 550 students returned the questionnaire packets. Final data analysis included 298 students after deleting incomplete data. METHODS: Participants completed six questionnaires: (1) Background and Sexual Behavior Questionnaire, including items related to perceived risk of sexual behavior, (2) Parent-Adolescent Communication Scale, and four scales related to TpB construct: (3) modified Premarital Sexual Attitude Scale, (4) Referent group Approval of Sex Behavior Scale, (5) Sexual Abstinence Efficacy Scale and (6) modified version of Doswell's Intention of Sexual Behavior Scale. RESULTS: Premarital sexual attitude, abstinence self-efficacy and referent group norms were significant predictors of intention of premarital sex for male students with a large effect, but only attitude and norms predicted intention of premarital sex for female students. CONCLUSION: The TpB may be an effective theory to guide the development of theory-driven sexual abstinence interventions to reduce risky sexual behavior for Korean males, while the Theory of Reasoned Action may be an effective theory for Korean females.

Environmental exposures, toxicologic mechanisms, and adverse pregnancy outcomes.

Environmental risk factors (defined as those agents and stresses that are generally the responsibility of environmental agencies) are often tangible indicators of economic and social disparity in the United States. Many site-specific analyses have reported that communities of color and poverty are exposed more often and more intensively to such environmental hazards as lead, air pollution, agrochemicals, incinerator emissions, and releases from hazardous waste sites. Thus, exposures to these toxicants may explain part of the socioeconomic disparity that is observed in terms of risks of adverse pregnancy outcomes. The purpose of this study was to describe the associations between certain environmental exposures and reproductive outcomes through a discussion of both epidemiologic and animal model studies. In addition, we list potential sources of exposure data and describe physiologic changes in pregnancy that may increase the likelihood of both external exposures and increased internal dose. Several models for further study of environmental risk factors are suggested to increase our understanding of gene-environment interactions toward the goal of indentifying preventable risk factors to improve reproductive outcomes of particular concern to disadvantaged populations.

Research strategies for optimizing pregnancy outcomes in minority populations.

The elimination of disparities in pregnancy outcomes is a common goal of clinicians and scientists and requires the collaboration of many disciplines to address the complexities of this still-increasing perinatal health concern. This commentary synthesizes the presentations and dialogue from a multidisciplinary workgroup meeting that was sponsored by the National Institute of Nursing Research in 2003. Concepts that are central to our understanding of the development and expression of such disparities are summarized, and approaches that are recognized as important in multiple disciplines that include basic, clinical, and social sciences are presented. Research strategies to foster a multidisciplinary research agenda are presented as a basis for future endeavors to improve pregnancy outcomes.

Evidence of increased oxidative stress, unexplained by lipid changes, is present in nulliparous black women from early gestation.

OBJECTIVE: We tested the hypothesis that race-specific lipid changes in pregnancy could predispose to oxidative stress and might increase the risk of preeclampsia for black women. STUDY DESIGN: Blood samples were obtained at five time points in pregnancy and postpartum for 15 black and 15 white women with normal pregnancy. Serum or plasma samples were analyzed for cholesterol, triglycerides, LDL cholesterol, HDL total and subfractions, free fatty acids, uric acid, and malondialdehyde (MDA). RESULTS: Cholesterol and LDL-cholesterol values were higher in white women than in black women (RMANOVA, p = 0.04) while MDA values were higher in blacks throughout pregnancy (RMANOVA, p = 0.03). Although not significantly different, black women had lower mean triglycerides, while mean total HDL and subfractions HDL2 and HDL3 were higher for black women. Both races evidenced smaller, denser LDL particle size with advancing gestation and a return to early pregnancy LDL particle size by 6 weeks' gestation. CONCLUSION: These data do not support quantitative lipid change as the explanation for the increased incidence of preeclampsia in black women. Despite this, black women manifest increased evidence of oxidative stress, postulated to be an important contributor to the pathogenesis of preeclampsia from early gestation.

Homocysteine and folic acid are inversely related in black women with preeclampsia.

Black women have an increased risk of preeclampsia compared with white women. Plasma homocysteine is increased in preeclampsia. Homocysteine concentrations are affected by nutritional deficiencies, particularly decreased folic acid and B12, leading to increased homocysteine. Previous studies have reported racial differences in nutritional intake including folic acid. Therefore, we investigated whether there were racial differences in plasma homocysteine, folic acid, and vitamin B12 among women with preeclampsia. We tested for an association between homocysteine and folic acid and B12, and we hypothesized an inverse relationship of homocysteine and folic acid in preeclampsia, more so in black women in whom preeclampsia developed. Black women with preeclampsia (n=26) had elevated homocysteine concentrations (8.7+/-1.4 micromol/L) compared with black women with normal pregnancy (n=52, 7.6+/-0.5 micromol/L), white women with preeclampsia (n=34, 7.5+/-0.6 micromol/L), and white women with normal pregnancy (n=48, 5.5+/-0.3 micromol/L). Folic acid concentrations were lower in black women (14.1+/-0.8 ng/mL) compared with white women (18.5+/-0.9 ng/mL, P<0.01). However, plasma homocysteine was inversely related to folic acid only among black women with preeclampsia (r=-0.23, P=0.01). These racial differences may have implications for the higher rates of preeclampsia in this group and may have long-term implications for future cardiovascular risk. Racial differences in diet, adherence to folic acid supplementation, or interactions of nutritional and maternal factors warrant further study by race and pregnancy status.