Compound gravity receptor polarization vectors evidenced by linear vestibular evoked potentials.

The utricle and saccule are gravity receptor organs of the vestibular system. These receptors rely on a high-density otoconial membrane to detect linear acceleration and the position of the cranium relative to Earth's gravitational vector. The linear vestibular evoked potential (VsEP) has been shown to be an effective non-invasive functional test specifically for otoconial gravity receptors (Jones et al., 1999). Moreover, there is some evidence that the VsEP can be used to independently test utricular and saccular function (Taylor et al., 1997; Jones et al., 1998). Here we characterize compound macular polarization vectors for the utricle and saccule in hatchling chickens. Pulsed linear acceleration stimuli were presented in two axes, the dorsoventral (DV, +/- Z axis) to isolate the saccule, and the interaural (IA, +/- Y axis) to isolate the utricle. Traditional signal averaging was used to resolve responses recorded from the surface of the skull. Latency and amplitude of eighth nerve components of the linear VsEP were measured. Gravity receptor responses exhibited clear preferences for one stimulus direction in each axis. With respect to each utricular macula, lateral translation in the IA axis produced maximum ipsilateral response amplitudes with substantially greater amplitude intensity (AI) slopes than medially directed movement. Downward caudal motions in the DV axis produced substantially larger response amplitudes and AI slopes. The results show that the macula lagena does not contribute to the VsEP compound polarization vectors of the sacculus and utricle. The findings suggest further that preferred compound vectors for the utricle depend on the pars externa (i.e. lateral hair cell field) whereas for the saccule they depend on pars interna (i.e. superior hair cell fields). These data provide evidence that maculae saccule and utricle can be selectively evaluated using the linear VsEP.

Balancing recruitment and protection: children as research subjects.

Since 1994, federal guidelines for research in the United States have called for the inclusion of special populations, among them, children, in clinical research (National Institutes of Health, 1998). While the guidelines are intended to assure the fair distribution of research benefits to children, this federal mandate has created an ethical dilemma for researchers. Health professionals involved in research with children are called on to balance improving access and recruitment of children for clinical trials with the need to protect this very vulnerable population. Given this balancing act, it is important for nurse-researchers to be familiar with the issues of informed consent and assent with children. Our article reviews instances of exploitation of children in research, laws and federal regulations on informed consent and assent designed to protect children, and research on factors that affect children's capacity to consent/assent. We conclude with recommendations to assure a proper balance between the need to recruit children into clinical trials and the need to protect their rights as human subjects.

Pilot study to evaluate the efficacy of hyperbaric oxygen therapy in improving the survival of reattached auricular composite grafts in the New Zealand White rabbit.

OBJECTIVE: This investigation is a prospective, randomized, blinded study seeking to evaluate the efficacy of hyperbaric oxygen (HBO) therapy in improving the survival of the reattached auricular composite graft. STUDY DESIGN: Twenty New Zealand White rabbits were randomly assigned to control (10) and treatment (10) groups in a prospective fashion. After amputation and reattachment of measured segments of each ear, the treatment group received 14 HBO treatments for 10 days. The control group received only standard postoperative care. On postoperative day 18, the surviving composite grafts were measured, recorded, and statistically analyzed. RESULTS: The mean percentage of graft survival for the control group was 0.31% (range 0%-2.5%), and the mean for the group receiving HBO was 15.94% (range 0%-38%). A median test was used to evaluate this difference, which was found to be statistically significant (P = 0057). CONCLUSION: Our study appears to indicate a possible survival benefit for the composite grafts in those rabbits that received HBO treatments. We believe that there are several significant difficulties with the rabbit as a model for this study, but we are encouraged at this point that a limited measurable benefit was observed. Further investigations with HBO appear to be warranted at this time.

Nurse managed prenatal programs affect outcomes for corporations.

Faced with higher medical costs and increased insurance premiums, corporations are focusing on health promotion and wellness. With increasing numbers of women in the workforce, corporations have identified the need for prenatal programs. By developing, initiating, and evaluating outcome-based prenatal programs nurses can target the health care needs of this select population. One such program documented several outcomes including improved employee health and an 86% reduction in maternal/newborn costs.

Adolescent mothers' perceptions of the neonatal intensive care unit environment.

The neonatal intensive care unit (NICU) environment has been found to be a major source of distress for older parents, but what about adolescent mothers? A prospective, descriptive study was conducted to describe adolescent mothers' perceptions of the stressors found in the NICU environment. Data were collected using the NICU Parental Stress Scale and a demographic data form. These 46 mothers found that the most stressful aspects of the NICU were parental role alterations and the infant's appearance and behavior. Less stressful were the sights and sounds of the NICU and communication with staff. Nurses should continue to identify and alleviate stressors that can compromise the parenting experience of mothers of all age groups.

Neonatal case management: a challenge for advanced practice nurses.

With a presidential commitment to health care reform, advanced practice nurses (APNs) are challenged to rethink critical care for the growing number of premature infants born each year. Threats of shortened lengths of stay force APNs to case manage the long-term needs of compromised neonates in their homes and communities. Recent studies have shown that earlier discharge from neonatal intensive care units with proper home follow-up is not only cost saving, but is also safe and beneficial to the infant and family. Further documentation is required to ensure that quality outcomes are not compromised in health care reform.

Impaired cerebral vascular blood flow in the premature infant.

Approximately 40% to 60% of infants born prior to 32 weeks' gestation experience an IVH. The impact of unregulated CBF precipitating an IVH has ramifications far beyond the walls of the neonatal intensive care unit. Infants who survive alterations in CBF may experience impaired neurologic development. Cerebral ischemia can lead to poor articulation, dysphasia, attention deficit, low intelligence quotient, dyspraxia, dyssynergia, spasticity, and short-term memory dysfunction. The neurologic and intellectual development of these premature infants must continue to be a crucial factor in planning their nursing care.

Cost containment and quality of life. An experiment in compassion for physicians.

A review of emergency department visits during a 2-year period and before and after the liberation of physicians from a requirement of gatekeeping for some patients during the night showed no significant increases in the use or costs of services to our Medicaid enrollees for all but children under 6 years of age between 10 PM and midnight. We recommend that a more humane and practical view be taken of middle-of-the-night gatekeeping requirements for physicians functioning in managed-care environments. We also suggest, as many hospitals have already learned, that the costs of emergency department services for Medicaid patients can be reduced and that care may be enhanced by the offering of 24-hour urgent care services at or near the emergency department.