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Thomas C Hulsey

Publications and source records attributed to Thomas C Hulsey.

At least 19 recordsLinked to original sources
PubMed2006

Parameter selection for and implementation of a web-based decision-support tool to predict extubation outcome in premature infants.

BACKGROUND: Approximately 30% of intubated preterm infants with respiratory distress syndrome (RDS) will fail attempted extubation, requiring reintubation and mechanical ventilation. Although ventilator technology and monitoring of premature infants have improved over time, optimal extubation remains challenging. Furthermore, extubation decisions for premature infants require complex informational processing, techniques implicitly learned through clinical practice. Computer-aided decision-support tools would benefit inexperienced clinicians, especially during peak neonatal intensive care unit (NICU) census. METHODS: A five-step procedure was developed to identify predictive variables. Clinical expert (CE) thought processes comprised one model. Variables from that model were used to develop two mathematical models for the decision-support tool: an artificial neural network (ANN) and a multivariate logistic regression model (MLR). The ranking of the variables in the three models was compared using the Wilcoxon Signed Rank Test. The best performing model was used in a web-based decision-support tool with a user interface implemented in Hypertext Markup Language (HTML) and the mathematical model employing the ANN. RESULTS: CEs identified 51 potentially predictive variables for extubation decisions for an infant on mechanical ventilation. Comparisons of the three models showed a significant difference between the ANN and the CE (p = 0.0006). Of the original 51 potentially predictive variables, the 13 most predictive variables were used to develop an ANN as a web-based decision-tool. The ANN processes user-provided data and returns the prediction 0-1 score and a novelty index. The user then selects the most appropriate threshold for categorizing the prediction as a success or failure. Furthermore, the novelty index, indicating the similarity of the test case to the training case, allows the user to assess the confidence level of the prediction with regard to how much the new data differ from the data originally used for the development of the prediction tool. CONCLUSION: State-of-the-art, machine-learning methods can be employed for the development of sophisticated tools to aid clinicians' decisions. We identified numerous variables considered relevant for extubation decisions for mechanically ventilated premature infants with RDS. We then developed a web-based decision-support tool for clinicians which can be made widely available and potentially improve patient care world wide.

Birth Weight↗
PubMed2006

The role of personality and other factors in a mother's decision to initiate breastfeeding.

The objective of the study was to measure the impact of personality and other factors on the decision to initiate breastfeeding. Mothers were enrolled (24-96 hours postpartum) and were classified as fully breastfeeding, formula-feeding, or combination-feeding. A semi-structured interview about maternal sociodemographics and attitudes and a standardized personality inventory (NEO-PI-R) were conducted. Eighty-seven mothers completed the study: 50 breastfeeders, 6 combination feeders, and 31 formula feeders. Because of small numbers, combination-feeder mothers (n = 6) were excluded from analyses. Maternal age, marriage, ethnicity, and socioeconomic status were significantly associated with breastfeeding. Breastfeeding and formula-feeding groups differed on 3 personality domains: extraversion (53.3 breastfeeding vs 46.9 formula-feeding, P = .002), openness (51.6 vs 46.2, P = .008), and agreeableness (48.5 vs 41.5, P = .01). In a multiple variable logistic regression model, extraversion (P = .03) and openness (P = .003) remained significant. Sociodemographics, experiential factors, and specific personality characteristics of mother were independently associated with maternal feeding decision.

Adult↗
PubMed2005

An evaluation of Echinacea angustifolia in experimental rhinovirus infections.

BACKGROUND: Echinacea has been widely used as an herbal remedy for the common cold, but efficacy studies have produced conflicting results, and there are a variety of echinacea products on the market with different phytochemical compositions. We evaluated the effect of chemically defined extracts from Echinacea angustifolia roots on rhinovirus infection. METHODS: Three preparations of echinacea, with distinct phytochemical profiles, were produced by extraction from E. angustifolia roots with supercritical carbon dioxide, 60 percent ethanol, or 20 percent ethanol. A total of 437 volunteers were randomly assigned to receive either prophylaxis (beginning seven days before the virus challenge) or treatment (beginning at the time of the challenge) either with one of these preparations or with placebo. The results for 399 volunteers who were challenged with rhinovirus type 39 and observed in a sequestered setting for five days were included in the data analysis. RESULTS: There were no statistically significant effects of the three echinacea extracts on rates of infection or severity of symptoms. Similarly, there were no significant effects of treatment on the volume of nasal secretions, on polymorphonuclear leukocyte or interleukin-8 concentrations in nasal-lavage specimens, or on quantitative-virus titer. CONCLUSIONS: The results of this study indicate that extracts of E. angustifolia root, either alone or in combination, do not have clinically significant effects on infection with a rhinovirus or on the clinical illness that results from it.

Adult↗
PubMed2005

Moderate hypothermia in neonatal encephalopathy: efficacy outcomes.

Therapeutic hypothermia holds promise as a rescue neuroprotective strategy for hypoxic-ischemic injury, but the incidence of severe neurologic sequelae with hypothermia is unknown in encephalopathic neonates who present shortly after birth. This study reports a multicenter, randomized, controlled, pilot trial of moderate systemic hypothermia (33 degrees C) vs normothermia (37 degrees C) for 48 hours in neonates initiated within 6 hours of birth or hypoxic-ischemic event. The trial tested the ability to initiate systemic hypothermia in outlying hospitals and participating tertiary care centers, and determined the incidence of adverse neurologic outcomes of death and developmental scores at 12 months by Bayley II or Vineland tests between normothermic and hypothermic groups. Thirty-two hypothermic and 33 normothermic neonates were enrolled. The entry criteria selected a severely affected group of neonates, with 77% Sarnat stage III. Ten hypothermia (10/32, 31%) and 14 normothermia (14/33, 42%) patients expired. Controlling for treatment group, outborn infants were significantly more likely to die than hypoxic-ischemic infants born in participating tertiary care centers (odds ratio 10.7, 95% confidence interval 1.3-90). Severely abnormal motor scores (Psychomotor Development Index < 70) were recorded in 64% of normothermia patients and in 24% of hypothermia patients. The combined outcome of death or severe motor scores yielded fewer bad outcomes in the hypothermia group (52%) than the normothermia group (84%) (P = 0.019). Although these results need to be validated in a large clinical trial, this pilot trial provides important data for clinical trial design of hypothermia treatment in neonatal hypoxic-ischemic injury.

Child Development↗
PubMed2005

Moderate hypothermia in neonatal encephalopathy: safety outcomes.

Hypoxic-ischemic injury may cause multisystem organ damage with significant aberrations in clotting, renal, and cardiac functions. Systemic hypothermia may aggravate these medical conditions, such as bradycardia and increased clotting times, and very little safety data in neonatal hypoxic-ischemic injury is available. This study reports a multicenter, randomized, controlled pilot trial of moderate systemic hypothermia (33 degrees C) vs normothermia (37 degrees C) for 48 hours in infants with neonatal encephalopathy instituted within 6 hours of birth or hypoxic-ischemic event. The best outcome measures of safety were determined, comparing rates of adverse events between normothermia and hypothermia groups. A total of 32 hypothermia and 33 normothermia neonates were enrolled in seven centers. Adverse events and serious adverse effects were collected by the study team during the hospital admission, monitored by an independent study monitor, and reported to Institutional Review Boards and the Data and Safety Monitoring Committee. The following adverse events were observed significantly more commonly in the hypothermia group: more frequent bradycardia and lower heart rates during the period of hypothermia, longer dependence on pressors, higher prothrombin times, and lower platelet counts with more patients requiring plasma and platelet transfusions. Seizures as an adverse event were more common in the hypothermia group. These observed side effects of 48 hours of moderate systemic hypothermia were of mild to moderate severity and manageable with minor interventions.

Acidosis↗
PubMed2005

The influence of race on fetal outcome.

The purpose of this study was to examine racial differences in fetal death by gestational age among South Carolinians during 1999 to 2000 in an attempt to identify sociodemographic risk factors that may contribute to the refinement of care protocols. This historical cohort design appended the 1999 to 2000 South Carolina Vital Records fetal death file (N = 944) to the birth file (N = 99, 726) to perform secondary data analysis. Inclusion criteria were maternal South Carolina residency, delivery of a singleton in South Carolina, and racial identification as white or black. Independent associations between race (black or white), gestational age categories of deliveries (fetal death or live birth), and maternal sociodemographic characteristics (maternal age and prenatal care) were examined using chi2 analysis. Black and white fetal mortality rates (FMRs) were examined. Logistic regression was used to control for confounding variables. The study sample consisted of 63.4% white and 36.6% black for all deliveries; 40.89% white and 59.11% black for fetal deaths. There was a significant racial difference in gestational age categories, initiation of prenatal care, maternal age, and fetal death rates (p = 0.0001). The black FMR was nearly 2.5 times greater than the white rate (p < 0.0001; 95% confidence interval, 2.2 to 2.9). There was an independent association between race and gestational age at fetal death (p = 0.0001) as well as race and maternal age. Results did not remain statistically significant after controlling for confounding variables. In this study, we identified several factors associated with an increased risk of fetal death. However, after controlling for gestational age, the odds of fetal death among blacks were no longer significantly elevated in comparison to those of whites. Future studies that examine racial disparities should consider gestational age in analytic models. Identifying racial demographics and behavioral risks may contribute to refinements in care protocols for high-risk mothers in an effort to reduce fetal mortality.

Adolescent↗
PubMed2005

Maternal prepregnant body mass index and weight gain related to low birth weight in South Carolina.

OBJECTIVES: The primary purpose of this study was to describe the proportion of low birth weight that could be potentially prevented by programs focusing on maternal prepregnant body mass index (BMI) and/or weight gain during pregnancy. METHODS: In this historic cohort design, study data consisted of birth certificates linked to the Pregnancy Risk Assessment Monitoring System for South Carolina resident women delivering in South Carolina during 1998 and 1999. Statistical analysis was conducted with the use of chi2, population-attributable risk, and logistic regression. The analysis was performed using SUDAAN to accommodate the analysis weight and extrapolate the sample data to the South Carolina state population. RESULTS: Eight percent of the very low birth weight (VLBW) rate in South Carolina can be attributed to inadequate weight gain in pregnancy. Approximately 19% of the state's VLBW rate can be attributed to either underweight or overweight BMI at conception. Women with less than adequate weight gain were 1.4 times more likely to deliver a VLBW baby and 1.9 times more likely to deliver a moderately low birth weight baby as compared with women with adequate weight gain. CONCLUSIONS: Appropriate maternal BMI at conception followed by adequate weight gain during pregnancy may have a substantial influence on reducing the number of low birth weight deliveries.

Body Mass Index↗
PubMed2004

Predicting extubation outcome in preterm newborns: a comparison of neural networks with clinical expertise and statistical modeling.

Even though ventilator technology and monitoring of premature infants has improved immensely over the past decades, there are still no standards for weaning and determining optimal extubation time for those infants. Approximately 30% of intubated preterm infants will fail attempted extubation, requiring reintubation and resuming of mechanical ventilation. A machine-learning approach using artificial neural networks (ANNs) to aid in extubation decision making is hereby proposed. Using expert opinion, 51 variables were identified as being relevant for the decision of whether to extubate an infant who is on mechanical ventilation. The data on 183 premature infants, born between 1999 and 2002, were collected by review of medical charts. The ANN extubation model was compared with alternative statistical modeling using multivariate logistic regression and also with the clinician's own predictive insight using sensitivity analysis and receiver operating characteristic curves. The optimal ANN model used 13 parameters and achieved an area under the receiver operating characteristic curve of 0.87 (out-of-sample validation), comparing favorably with multivariate logistic regression. It also compared well with the clinician's expertise, which raises the possibility of being useful as an automated alert tool. Because an ANN learns directly from previous data obtained in the institution where it is to be used, this makes it particularly amenable for application to evidence-based medicine. Given the variety of practices and equipment being used in different hospitals, this may be particularly relevant in the context of caring for preterm newborns who are on mechanical ventilation.

Decision Making↗
PubMed2004

Obstetric and neonatal outcomes in grand multiparity.

OBJECTIVE: To compare the incidence of antenatal and intrapartum complications and neonatal outcomes among grand multiparas with age-matched multiparas. METHODS: Six hundred twenty-one grand multiparas (para more than 4) women were prospectively compared with 621 age-matched multiparous (para 2-4) controls. RESULTS: Grand multiparity was associated with low socioeconomic status and education (odds ratio [OR]6.4; 95% confidence interval [CI] 4.5, 9.0), poorer prenatal care (OR 3.1; 95% CI 1.5, 6.1), smoking (OR 2.2; 95% CI 1.5, 3.2), and alcohol consumption (OR 9.0; 95% CI 2.1, 39.3). Grand multiparas had a higher body mass index (OR 1.5; 95% CI 1.2, 1.9) and rate of insulin-dependent gestational diabetes (OR 1.7; 95% CI 1.02, 3.1). They had more previous intrauterine (OR 4.2; 95% CI 1.5, 11.3) and perinatal deaths (OR 3.2; 95% CI 2.0, 5.0). They had fewer intrapartum complications (arrests of cervical dilatation [OR 0.19; 95% CI 0.06, 0.66], instrumental deliveries [OR 0.31; 95% CI 0.16, 0.59], and fever during labor [OR 0.47; 95% CI 0.26, 0.86]). Conditional logistic regression models found that grand multiparity was the most closely correlated factor to a previous history of fetal death (OR 4.3; 95% CI 1.6, 11.6), but it was not an independent predictor of insulin-dependent gestational diabetes mellitus (OR 1.3; 95% CI 0.75, 2.2). CONCLUSION: Grand multiparas, when compared with same-age multiparous controls, appear to have fewer intrapartum complications. However, they present several prenatal risk factors that require special antenatal care. LEVEL OF EVIDENCE: II-3

Adult↗
PubMed2004

Pregnant adolescents' preferences for labor pain management.

OBJECTIVES: The purpose of this study was to examine the obstetric anesthesia method used, based on the patient's age. Confounding variables analyzed were the effect on labor pain management choices of parity, race, prenatal care participation, insurance status, and length of labor. METHODS: This was a case control study from the Medical University of South Carolina (MUSC). The primary outcome measured was regional anesthesia (RA) use in labor. The exposure groups were based on the patient's age. All women aged 11 years and older who delivered vaginally from 1996 to 2001 were included; 7,583 patients met inclusion criteria. Results were analyzed using chi2 statistic, univariate analysis, ANOVA, and logistic regression. RESULTS: We found that primiparous adolescents used RA less than primiparous women over age 20. This association is not found in multiparous teens. Patients with shorter labors, black women, those without prenatal care, and older patients lacking private insurance declined RA more often. CONCLUSIONS: RA is the most utilized form of obstetric pain management in the last decade. In primiparous adolescents, declining RA cannot be explained by length of labor, race, insurance status, or prenatal care participation.

Adolescent↗
PubMed2003

Preeclampsia and human reproduction. An essay of a long term reflection.

Hypertensive disorders of pregnancy (HDP: pregnancy-induced hypertension, preeclampsia, eclampsia) affect approximately 10% of human births. Women are at increased risk for HDP during their first conception; and/or when the conception is with a new partner (new paternity); when conception occurs very shortly after the beginning of their sexual relationship. A primary cause of preeclampsia is the defect of the normal human-specific deep endovascular invasion of trophoblast, which is a consequence of the nutritional demands of growth of the human fetal brain. The occurrence of preeclampsia represents a reproductive disadvantage unique to humans compared with other mammals. As such, it may have played a significant role in shaping human reproduction and, therefore, human sexuality. This deep implantation/preeclampsia phenomenon may explain many anthropological mysteries of human sexuality that do not exist in other mammalian species (and primates). These include: very low fertility rate, concealed ovulation, all year long 'apparent-waste-of-efficiency' sexuality, absence of sperm competition in human females at the time of conception, and the unexplained testicle size in human males compared with relevant primates. Further, this deep trophoblastic implantation (and its failure in preeclampsia) in humans might be a decisive condition of hominization between great apes and all the other Homo genuses. This frontier might even have occurred inside these Homo lineages: because of their relatively small brains, the first species of Homo might not have presented the deep trophoblastic invasion described in Homo sapiens.

Adaptation, Physiological↗
PubMed2003

Web-based prediction of extubation outcome in premature infants on mechanical ventilation using an artificial neural network.

The web-based implementation of a decision-support tool for the prediction of extubation outcome in mechanically ventilated premature infants enables the integration of advanced and computationally intensive modeling approaches with easy-usage, no maintenance requirements and wide availability. Accordingly, the artificial neural network predictive tool developed provides decision-support in determining whether to extubate a premature infant to clinicians in NICUs anywhere with access to the Internet.

Decision Making, Computer-Assisted↗
PubMed2003

Teen pregnancy in South Carolina: a local needs assessment of Charleston County.

Although there has been recent improvement, teen pregnancy continues to be a significant problem, especially in South Carolina where the birth rate to adolescents is higher than the national average. As this is a complex issue, many different interventions including both primary and secondary prevention as well as modification of programs to fit each individual community will be necessary. One initial approach to pregnancy prevention program implementation is a needs assessment of current interventions compared with teen birth rates in a community. This report of a needs assessment for Charleston County revealed a discrepancy between the location of most pregnancy prevention programs (urban areas of the county) and the higher teen birth rates (rural areas of the county,) establishing areas that will be targeted for additional services. Other counties throughout South Carolina may find this approach useful in coordination of community efforts to reduce teen pregnancy.

Adolescent↗
PubMed2002

Reduced emergency department utilization associated with school-based clinic enrollment.

PURPOSE: To evaluate the change in emergency department utilization before and after enrollment in a school-based clinic (SBC). METHODS: This study was a retrospective cohort study comparing emergency department visit rate before and after SBC enrollment based on chart review. An initial cohort of 10- to 15-year-olds who used a local emergency department was divided into two samples: those who had been enrolled in the SBC and those who had not. Emergency department charts were reviewed for visits that occurred during the initial year and two subsequent school years. The change in visit rate for each sample group was measured for each school year evaluated. RESULTS: The initial cohort consisted of 2852 youth, 344 of whom who lived in the high school attendance zone. Of these, the number of students enrolled in both the high school and the SBC was 43; the number enrolled in the high school but not in the clinic was 48. The emergency department visit rate decreased for both groups for each school year evaluated; however, this decrease was significant only for the SBC sample with a 41% to 57% decrease in emergency department utilization, 18% greater than the decrease in students who did not use the SBC. CONCLUSIONS: Accessible, prevention-oriented health care provided in a SBC can decrease the utilization of episodic health care in an emergency department.

Adolescent↗
PubMed2002

Evolutionary adaptations to pre-eclampsia/eclampsia in humans: low fecundability rate, loss of oestrus, prohibitions of incest and systematic polyandry.

Gestational-hypertension/pre-eclampsia occurs in approximately 10% of human pregnancies. This persistent complication of pregnancy has been reported to occur more frequently in couples conceiving very shortly after the beginning of their sexual relationship and/or after a change in paternity. Primipaternity may be the leading cause of pre-eclampsia in women under 30 years of age when genetic susceptibility to cardio-vascular disease has not yet been expressed, especially in women before their twenties, who for the last 40,000 years have perhaps comprised the age group when the majority of parturients classified as Homo sapiens sapiens initiated their reproductive life. In terms of evolution, the prevalence of pre-eclampsia represents a distinct reproductive disadvantage in humans as compared with other mammals. Indeed, pre-eclampsia is a consequence of the defect of the normal human-specific deep endovascular invasion of the trophoblast. The large size of the human fetal brain imposing this deep trophoblastic invasion induced the need for major immunogenetic compromises in terms of paternal-maternal tissue tolerance. The price that mankind has had to pay to adapt to the pre-eclampsia risk is a low fecundability rate and therefore loss of oestrus, possibly a step in the deviation between apes and hominids. Further, pre-eclampsia risk may be a contributing factor leading to the rejection of systematic polyandry in human societies and have influenced prohibition of incest.

Adaptation, Biological↗
PubMed2002

A statistical model to predict nonsurvival in congenital diaphragmatic hernia.

OBJECTIVE: To develop a predictive model using echocardiographic indices to identify nonsurvivors from survivors in preoperative patients with congenital diaphragmatic hernia (CDH). STUDY DESIGN: Eight cases of CDH, with a mortality rate of 38%, underwent echocardiographic study before surgical repair. Left ventricular mass (LVMASS) using the area-length method of Wyatt et al. and fractional shortening (FS) by M-mode measurements were determined. RESULTS: We identified a nonlinear nonoverlapping distribution that predicted nonsurvivors from survivors, p=0.04. Multiple regression analysis demonstrated the quantity (LVMASS x FS)(1/2) to be correlated with nonsurvival with a coefficient of determination r(2)=0.55. Comparison of the means of the quantity (LVMASS x FS)(1/2) for the two groups suggested two distinct populations, p=0.04. CONCLUSION: The mathematical quantity (LVMASS x FS)(1/2) calculated from echocardiographic measurements obtained preoperatively in babies with CDH may predict nonsurvival despite maximal intervention.

Female↗
PubMed2002

Success factors and hurdles in quality improvement in a children's hospital.

A set of nurse/respiratory therapist-driven algorithms developed by a multidisciplinary team with the goal of "liberating" mechanically ventilated pediatric patients more rapidly from the ventilator resulted in sustained improvement over a 47-month period. The difference between expected and observed billed ventilator hour totals was over 22,000 hours (475 hours per month), a 17.5% reduction, which was significant at the P =.03 level by multiple linear regression analysis. Length of stay and mortality rate were unchanged. This difference represents a measure of the unrecognized cost of a nonstandardized approach to the weaning process. This reports reviews this team's success factors and hurdles and offers practical suggestions for pediatric surgeons interested in leading quality improvement initiatives.

Adolescent↗