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Biomedical subjects

M C Mackey

Publications and source records attributed to M C Mackey.

At least 37 records · Page 2Linked to original sources
PubMed1998

The preterm labor experience: a balancing act.

The purpose of the study was to identify how women described, interpreted, and managed their preterm labor experience. Ten married, middle-class women participated in an in-depth, tape-recorded interview in the hospital after preterm labor was stabilized; periodically over the telephone after discharge from the hospital; and in the hospital, home, or via telephone after birth, for a total of 31 interviews. Using qualitative data analysis techniques, the findings were conceptualized as five recursive stages: becoming aware that something was wrong and feeling unbalanced, making sense of the experience as they sought to understand why preterm labor occurred, trying different strategies to re-create a balance in their lives, addressing other life stressors that threatened restoring balance, and emerging from the preterm labor experience with added growth. An increased understanding of the preterm labor experience from the women's perspective can be helpful to health care professionals and others who support women during pregnancy.

Adaptation, Psychological↗
PubMed1998

Women's evaluation of the labor and delivery experience.

The purpose of this study was to identify how women described and evaluated their labor and delivery experience and what factors were related to their responses. Sixty Lamaze-prepared, married multigravidae, aged 21 to 37 years, participated in this qualitative field study. Detailed, open-ended tape-recorded interviews were conducted on the postpartum unit of a community hospital or in the women's homes early during the postpartum period. Women evaluated their labor and delivery experience according to how well they perceived they had managed their own childbirth performance. Women who managed well viewed childbirth as positive, whereas women who had difficulty or managed poorly viewed it as both positive and negative. Women who managed well thought their own performance and the nature of labor and delivery (physical aspects) went well; women who had difficulty thought labor and delivery and the performance of others went well, but women who managed poorly had problems identifying anything that went well. There was overall agreement that the baby was the best part of the experience and that pain and pushing were the worst parts. Since women's evaluation of their labor and delivery experience may be related to the quality of their subsequent mothering, it is important to enhance their perceptions of their own performance, and thus their evaluation of the childbirth experience.

Adaptation, Psychological↗
PubMed1997

Staff evaluation of a high-risk pregnancy program.

A southeastern state implemented a multidisciplinary health care program for Medicaid eligible, medically high-risk pregnant women and their infants as part of a statewide effort to reduce perinatal morbidity and mortality. The purpose of this study was to obtain the staff's evaluation of this high-risk-pregnancy program. Clinical, supervisory, and clerical staff (N = 182) completed a questionnaire about the operation of the program and its perceived benefits. Staff identified program strengths: nurse case management, interdisciplinary structure, quality care, and positive health outcomes. Staff also identified program limitations including limited staff and time, inflexible protocols, administrative tasks, and narrow enrollment criteria. The majority of staff reported that the following barriers interfered with the effective operation of the program: paperwork, limited support, time, difficulty locating patients, and mandated time frames for patient contact. The majority of staff also reported that transportation most interfered with patient access to the program. The findings of this study support the need for ongoing staff evaluation of all perinatal health care programs.

Case Management↗
PubMed1994

Global stability in a delayed partial differential equation describing cellular replication.

Here we consider the dynamics of a population of cells that are capable of simultaneous proliferation and maturation. The equations describing the cellular population numbers are first order partial differential equations (transport equations) in which there is an explicit temporal retardation as well as a nonlocal dependence in the maturation variable due to cell replication. The behavior of this system may be considered along the characteristics, and a global stability condition is proved.

Animals↗
PubMed1994

Fluctuations in circulating cell numbers following chemotherapy or bone marrow transplant.

We study the effect of noise on the behaviour of a dynamic cell population model in which cell replication and maturation take place simultaneously. We assume that the maximum proliferative potential v fluctuates uniformly about a mean value of v, and show that a decrease in v and/or the input flux uin into the population can lead to an increase in the variance in the cellular efflux uf. We draw a qualitative correspondence between this behaviour and the commonly observed increase in the variance of circulating blood cell numbers following chemotherapy and radiotherapy, both of which lead to a decrease in v and uin, and bone marrow transplant which probably corresponds to a decrease in uin.

Blood Cells↗
PubMed1994

Women's evaluations of their labor and delivery nurses.

OBJECTIVE: To document women's evaluations of their labor and delivery nurses. DESIGN: An exploratory, qualitative study using open-ended, intensive, tape-recorded interviews. SETTING: Postpartum unit of a 400-bed midwestern hospital, except for two interviews in the women's homes. PARTICIPANTS: Sixty-one Lamaze-prepared, married, multigravidae, aged 21-37 years. RESULTS: Ninety percent of the women evaluated their nurses favorably, 10% unfavorably. Nurses were evaluated favorably because of their positive participation (80%), acceptance (78%), information giving (75%), encouragement (65%), presence (53%), and competence (7%). CONCLUSIONS: Although technical competence is important, manner, provision of supportive care, and acceptance of each woman as a unique human being may be a nurse's most important characteristics.

Adult↗
PubMed1992

Women's views of the preterm labor experience.

This study used a naturalistic approach to describe the childbearing woman's views of her preterm labor and delivery experience. Specifically, the aim was to identify how women describe, interpret, and manage preterm labor and subsequent preterm or term delivery. The views of 20 women who were hospitalized for preterm labor (before 37 weeks) were documented with semistructured, tape-recorded, in-depth interviews during their hospitalization for preterm labor and after delivery. Qualitative data analysis focused on the process of becoming a preterm labor patient and on living with a diagnosis of preterm labor. Women either waited for a period of time before seeking care or sought care immediately for the symptoms they were experiencing. Women interpreted the experience by identifying causes of preterm labor and by worrying about the outcome for the baby. Managing preterm labor required extensive, moderate, or limited changes in their lives. Women who delivered at term appeared to have more tangible help than those who delivered preterm. A better understanding of women's preterm labor experiences will provide clues to nurses on how to improve the care they provide.

Adolescent↗
PubMed1992

Women's views of postpartum sibling visitation.

The purpose of this study was to identify women's views of postpartum sibling visitation. Fifty-eight Lamaze-prepared, married multigravidae expressed their views on sibling visitation in a semistructured interview conducted during their postpartum hospitalization. The majority of women (84%) chose to have their children visit. Women identified positive and negative aspects of sibling visitation, explained reasons for not having siblings visit, and discussed reactions to separation from their children. The women believed both siblings and mothers benefitted emotionally from the visit. Negative aspects of sibling visitation included emotional reactions of mothers and siblings, lack of control between siblings and infants, and inconvenient location for the visit.

Adult↗
PubMed1991

Stability properties of proliferatively coupled cell replication models.

To address the possibility that proliferative disorders may originate from interactions between multiple populations of proliferating and maturing cells, we formulate a model for this process as a set of coupled nonlinear first order partial differential equations. Using recent results for the asymptotic behaviour of the solutions to this model, we demonstrate that there exists a region of coupling coefficients, maturation rates, and proliferation rates that will guarantee the stable coexistence of coupled cellular populations. The analysis shows that increases in the coupling between populations may ultimately lead to a loss of stability. Furthermore, the analysis indicates that increases (decreases) in the maturation and/or proliferation rates above (below) critical levels will lead either to instability in the populations or the destruction of one population and the persistence of the other.

Cell Division↗
PubMed1991

Strategies for change: nursing implementation of the birthing room.

Nurses were primary participants in introducing the birthing room for maternity care in their respective institutions. Based on tape-recorded interviews, this paper is a report on how the idea of a birthing room was initiated, the resistance it encountered, the eight strategies used to implement the idea, and appropriation of the idea by physicians. Although the examples are specific to the development of a birthing room, the strategies can be used by nurses to initiate other changes in perinatal health care delivery. In addition, increased collaboration between nurses and physicians may make some strategies obsolete.

Attitude of Health Personnel↗
PubMed1990

A deterministic approach to survival statistics.

Survival functions of the form p(t) = exp[-(lambda t) gamma], gamma greater than 0 can be generated by deterministic nonlinear, asymptotically stable (chaotic) dynamical systems. These systems thus provide an alternative to stochastic interpretations of failure time data. We use this approach to analyze cancer patient survival statistics. In this manner we are able to obtain fresh insights into the implications of negative and positive clinical trials.

Biometry↗
PubMed1990

Women's choice of childbirth setting.

As part of a larger study on women's views of the childbirth experience, this study was focused on women's choice of childbirth setting. Sixty-one Lamaze-prepared, married multigravidae between the ages of 21 and 37 and experiencing a normal pregnancy were interviewed twice: at 36-38 weeks gestation in their homes and during their postpartum stay in the hospital. Data were collected using (a) two semistructured interview guides consisting of open-ended questions about choosing a caregiver and the place of birth and about describing the actual childbirth experience, (b) a self-administered sociodemographic questionnaire, and (c) an obstetrical and infant data form. The tape-recorded interviews were transcribed verbatim. Qualitative data analysis was focused on reasons for choosing a hospital and a physician, reasons for choosing or not choosing a birthing room, and the outcomes of the decisions. An understanding of women's childbirth needs as reflected in their choices can suggest areas where flexibility might be built into maternity care programs.

Adult↗
PubMed1990

Complex dynamics and noise in simple neural networks with delayed mixed feedback.

This paper briefly reviews the role of mixed feedback, neural delays, and neural noise in the genesis of complex oscillations in neurological feedback systems. The results are concretely discussed within the context of recurrent inhibition in the mammalian hippocampus, and a hybrid version of the pupil light reflex with externally imposed electronic feedback.

Animals↗
PubMed1990

Women's preparation for the childbirth experience.

As part of a larger study on women's views of the childbirth experience, this study focused on women's preparation for childbirth. Sixty-one Lamaze-prepared, married multigravidae described their preparations for childbirth during intensive, tape-recorded interviews conducted at 36 to 38 weeks gestation. Qualitative data analysis indicated that women focused their descriptions of their past and expected childbirth experiences on the importance of the quality of their own performance in managing labor and delivery. Women described the ideal childbirth experience as a fast, short labor (84%) and one which they managed well (74%). They focused their review of past childbirth experiences on how well they had controlled their own behavior and evaluated their past performance as (a) managing well, 39%; (b) having difficulty, 31%, or (c) managing poorly, 30%. The majority of women (95%) reported that being informed about labor and delivery was generally helpful. They described information as valuable because it decreased fear which increased relaxation and decreased tension, which in turn increased their chances of managing labor well. Although women wanted to do a good job in managing labor, 59% were confident they would perform well and 41% were uncertain. The study results should help nurses recognize if women under their care also have the need to do a good job in managing labor and delivery and suggest ways for nurses to support women in their efforts, their successes, and their failures in meeting their labor management goals.

Adaptation, Psychological↗
PubMed1984

Globally asymptotic properties of proliferating cell populations.

This paper presents a general model for the cell division cycle in a population of cells. Three hypotheses are used: (1) There is a substance (mitogen) produced by cells which is necessary for mitosis; (2) The probability of mitosis is a function of mitogen levels; and (3) At mitosis each daughter cell receives exactly one-half of the mitogen present in the mother cell. With these hypotheses we derive expressions for the alpha and beta curves, the distributions of mitogen and cell cycle times, and the correlation coefficients between mother-daughter (rho md) and sister-sister (rho ss) cell cycle times. The distribution of mitogen levels is shown to be given by the solution to an integral equation, and under very mild assumptions we prove that this distribution is globally asymptotically stable. We further show that the limiting logarithmic slopes of alpha (t) and beta (t) are equal and constant, and that rho md less than or equal to while rho ss greater than or equal to 0. These results are in accord with the experimental results in many different cell lines. Further, the transition probability model of the cell cycle is shown to be a simple special case of the model presented here.

Animals↗