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D K Richardson

Publications and source records attributed to D K Richardson.

At least 19 recordsLinked to original sources

Epidural analgesia, intrapartum fever, and neonatal sepsis evaluation.

OBJECTIVE: Although several studies have documented an increase in maternal temperature associated with use of epidural analgesia during labor, none have investigated the impact of epidural use on the rate of intrapartum fever or the consequences for the fetus and newborn of this elevated maternal temperature. This study evaluates the impact of epidural analgesia use during labor on the rate of intrapartum fever and the performance of neonatal sepsis evaluations and treatment with antibiotics. METHODS: We studied 1657 nulliparous women with term pregnancies and singleton vertex fetuses who were afebrile at admission for delivery. The rates of maternal intrapartum fever >100.4 degrees F, neonatal sepsis evaluation, and neonatal antibiotic treatment according to use of epidural analgesia during labor were determined. Rate ratios and 95% confidence intervals (CI) were calculated. Multiple logistic regression was used to examine associations while controlling for confounding factors. RESULTS: Intrapartum fever >100.4 degrees F occurred in 14.5% of women receiving an epidural but only 1.0% of women not receiving an epidural (adjusted odds ratio (OR) = 14.5, 95% CI = 6.3, 33.2). Without epidural, the rate of fever remained low regardless of length of labor; with epidural, the rate of fever increased from 7% for labors < or = 6 hours to 36% for labors >18 hours. Neonates whose mothers received epidurals were more often evaluated for sepsis (34.0% vs 9.8%; adjusted OR = 4.3, 95% CI = 3.2, 5.9) and treated with antibiotics (15.4% vs 3.8%; adjusted OR = 3.9, 95% CI = 2.1, 6.1). Although 63% of women received epidurals, 96.2% of intrapartum fevers, 85.6% of neonatal sepsis evaluations, and 87.5% of neonatal antibiotic treatment occurred in the epidural group. CONCLUSIONS: Use of epidural analgesia during labor is strongly associated with the occurrence of maternal intrapartum fever, neonatal sepsis evaluations, and neonatal antibiotic treatment.

Analgesia, Epidural

Physician variations and the ancillary costs of neonatal intensive care.

OBJECTIVE: To determine to what degree attending physicians contribute to cost variations in the care of ventilator-dependent newborns. DATA SOURCES: Clinical data were merged with hospital financial data describing daily ancillary care costs during the first two weeks of life for 132 extremely low-birthweight newborns. In addition, each patient's chart was reviewed and illness severity graded using both SNAP and CRIB scores. STUDY DESIGN: This was a retrospective cohort of infants with birth weights of less than 1,001 grams and respiratory distress syndrome requiring mechanical ventilation in the first day of life. From birth up to two weeks of life, each received care directed by only one of 11 faculty neonatologists in a single university hospital. Data were analyzed stratified by these physicians. t-Test, ANOVA, and chi-square were used to assess bivariate data. For continuous data, log linear regressions were used. PRINCIPAL FINDINGS: After controlling for illness severity, when stratified by physicians, there were significant variances in the costs of ancillary resources for the study infants (p < .0001). Twenty-nine percent of the variance was attributable to whether or not the hospital day included the use of a ventilator. Physician identity explained only 5.6 percent (p < .0001). CONCLUSIONS: Physician identity was significant but explained less than 6 percent of the total variance in ancillary costs. Whether or not a ventilator was used during care was far more important. We conclude that for very sick babies during the first two weeks of care, reducing variations in ancillary services utilization among neonatologists will yield only modest savings.

Analysis of Variance

Outcomes of severely abnormal umbilical artery doppler velocimetry in structurally normal singleton fetuses.

OBJECTIVE: To construct a management guide for preterm pregnancies complicated by severely abnormal umbilical artery Doppler velocimetry. METHODS: A retrospective chart review was conducted on all cases of absent or reversed end-diastolic flow umbilical artery Doppler velocimetry identified through an ultrasound data base. Maternal and perinatal outcome variables were retrospectively reviewed and analyzed using both parametric and nonparametric statistical techniques. Seventy-one cases were identified over a 5-year period. After excluding multiple gestations, anomalous fetuses, and two cases that were terminated before 24 weeks' gestation, 56 singleton gestations remained for analysis. RESULTS: Among the 56 subjects, there were 45 survivors and 11 deaths (five fetal and six neonatal deaths). Nonsurvivors had a significantly lower gestational age at diagnosis and delivery. Nonsurviving live-born neonates had lower Apgar scores and were significantly smaller; however, there were no differences in proportion or severity of fetal growth restriction in survivors and nonsurvivors. There were no differences in last biophysical profile before delivery or interval from diagnosis of reversed end-diastolic flow to delivery. Predictors of nonsurvival were the presence of reversed end-diastolic flow and oligohydramnios. Perinatal mortality for reversed end-diastolic flow was 333/1000 and 94/1000 for absent end-diastolic flow. Risk for perinatal death was highly gestational age dependent. For delivery at less than 26 weeks, survival was one of four; at 26-27.9 weeks, survival was seven of 12; and at 28 weeks or greater, survival was 37 of 40. CONCLUSION: Whereas severely abnormal umbilical artery blood flow poses significant risk for pregnancy, perinatal mortality is dominated by gestational age at diagnosis and delivery. This may reflect the severity of the disease or the low survival of very immature gestations. Interventions on behalf of the fetus at very early gestational ages should be undertaken with caution.

Female

Prediction of respiratory distress syndrome by the novel dipalmitoyl phosphatidylcholine test.

OBJECTIVE: To determine the accuracy of a new test that measures the concentration in amniotic fluid (AF) of dipalmitoyl phosphatidylcholine (DPPC) in predicting respiratory distress syndrome (RDS). METHODS: The neonatal respiratory status of 176 newborns delivered within 72 hours of sampling was correlated with the concentration of DPPC, fluorescence polarization (TDx-FLM), lecithin-sphingomyelin ratio (L/S), and phosphatidyl-glycerol (Amniostat-FLM) in AF. RESULTS: Thirty infants developed RDS (17%), all correctly predicted with DPPC values less than 12 micrograms/mL (sensitivity 100%). Only six of the 146 cases with no RDS had DPPC values less than 12 micrograms/mL (specificity 96%). The overall accuracy of the DPPC test was 98% compared with 70% for TDx-FLM, 71% for the L/S, and 67% for Amniostat-FLM. Receiver operating characteristic analysis area was 0.98 +/- 0.01, indicating that the DPPC test is superior to both the TDx-FLM and L/S tests. CONCLUSION: The DPPC test is an accurate predictor of RDS and fetal lung maturity.

1,2-Dipalmitoylphosphatidylcholine

Racial differences in the predictive value of the TDx fetal lung maturity assay.

OBJECTIVE: Black newborns have lower rates of neonatal respiratory distress syndrome compared with nonblack newborns. This has been attributed to accelerated lung maturation. Previous studies have demonstrated a difference in the predictive value of the lecithin/sphingomyelin ratio, a test for lung maturity, between races. Our study examines the predictive value of the newer TDx Fetal Lung Maturity Surfactant-to-Albumin assay. STUDY DESIGN: We reviewed the records of 393 nonblack and 87 black infants delivered within 72 hours of the TDx FLM S/A assay testing. We compared the rates of neonatal respiratory distress syndrome by race, stratified by results. RESULTS: In our study population black newborns had less than one half the rate of respiratory distress syndrome compared with nonblack newborns (4.6% vs 10.4%). To adjust for possible differences in the timing of lung maturation, the results were stratified by the TDx FLM S/A assay result. Black race had a protective effect (Mantel-Haenszel weighted odds ratio 0.30, 95% confidence interval 0.06 to 0.93, p < 0.05). This significant racial difference remained when both TDx FLM S/A assay result and gestational age were controlled in a multiple logistic regression analysis. CONCLUSIONS: There are differences in the predictive value of the TDx FLM S/A assay among races. Black fetuses are less likely to have respiratory distress syndrome. The difference in rates of respiratory distress syndrome between races must be due to either a qualitative difference in the surfactant or to an anatomic difference in fetal lungs. Consideration should be given to a lower cutoff value for a mature test result in black women.

Black People

Prediction of fetal lung maturity in infants of diabetic mothers using the FLM S/A and disaturated phosphatidylcholine tests.

The authors evaluated the performance of the amniotic fluid surfactant to albumin ratio (FLM S/A), and disaturated phosphatidylcholine (DSPC) tests in assessing fetal lung maturity in infants of mothers with insulin-dependent diabetes mellitus antedating pregnancy. The distribution of the study population (n = 180) by class of diabetes was class B (27%); class C (28%); class D (29%); class F, FR and T (8%); and class R patients (8%). The diagnosis of respiratory distress syndrome (RDS) was the standard for evaluating the performance of FLM S/A and DSPC. The mean estimated gestational age was 37.4 weeks. Three infants (1.7%) were diagnosed with RDS. All three were delivered before 36 weeks. FLM S/A at the cut-off for "maturity" of > or = 70 mg/g, had a sensitivity of 66.6%, specificity of 94.9%, positive predictive value (PPV) of 18.2%, and negative predictive value (NPV) of 99.4%. DSPC at the cut-off for "maturity" of 1,000 micrograms/dL, had identical sensitivity and NPV, but lower specificity (89.2%) and PPV (9.5%) than FLM S/A. Both tests mispredicted maturity in the same case of RDS. The false "mature" rate of FLM S/A was 0.6% (95% confidence interval 0.0%-3.2%). The FLM S/A result of > or = 70 mg/g, obtained at or near-term, is a reliable predictor of the absence of RDS in infants of mothers with diabetes mellitus antedating pregnancy.

Albumins

Normal birth weight intensive care unit survivors: outcome assessment.

UNLABELLED: RATIONALE/OBJECTIVE: Although the short- and long-term outcome of low birth weight neonatal intensive care unit (NICU) survivors has been extensively studied, much less information is available for normal birth weight (NBW) infants (greater than or equal to 2500 g) who require NICU care. METHODS: To address this issue, we retrospectively examined the neonatal hospitalizations and 6-month health status of 521 consecutive NBW admissions to a single NICU. Information on the neonatal hospitalization was obtained from a review of medical records. Postdischarge health status was collected by using telephone survey techniques. RESULTS: NBW infants comprised 88.1% of births in this hospital and 35.4% of NICU admissions during the study period. The in-hospital mortality rate for this group was 2%. The median length of stay was 7.7 days (range 1 to 110 days) with median hospital charges of $5222 (range $565 to $317,820). Only 59% of infants required active intensive care therapy; the remainder received only intensive monitoring. The need for intensive therapy on admission day along with the presence of prematurity and congenital anomalies were significant predictors of hospital charges (R2 = 0.31, P < .01). After initial discharge, 10.1% of these infants required rehospitalization in the first 6 to 8 months of life. The rate of readmission among infants with congenital anomalies was over 30%. In addition to its association with neonatal resource consumption, the presence of congenital anomalies along with low 5-minute Apgar scores was associated with higher postdischarge resource use, as measured by frequency of physician visits, need for special medical items, and rate of rehospitalization (P < .05). CONCLUSIONS: NBW infants represent a significant percentage of NICU admissions, but for many of these patients NICU admission could be avoided if alternative care settings that provided intensive monitoring were available. In addition, these infants also incur higher rates of postdischarge use of medical care.

Birth Weight

Management of infection and occlusion associated with vascular access devices.

OBJECTIVE: To provide an overview of the etiology, assessment, diagnosis, and management of infections and occlusions that occur with venous access devices (VADs). CONCLUSIONS: The two major complications of VADs are infections and occlusions. Several strategies have been attempted to prevent and treat infections and occlusions; however, one specific method has yet to be determined. As a result, major controversies exist regarding the best method to manage these complications. Controlled randomized studies are needed to examine each type of VAD in relation to preventive and treatment strategies. IMPLICATIONS FOR NURSING PRACTICE: Preservation of VADs demands the development of and adherence to specific guidelines for maintenance care as well as an awareness of the incidence, presentation, and management of complications. Clearly, prevention is the key to effective management of infection and occlusion associated with VADs. Nurses must be familiar with institutional policies and procedures for the care of VADs.

Catheterization, Central Venous

Access to neonatal intensive care.

The birth of a high-risk infant is still a relatively rare, not totally predictable event; and the management of high-risk newborns requires highly skilled personnel and sophisticated technology. In the early days of neonatal intensive care, scarce resources led to regionalized systems of neonatal and, later, perinatal services, generally based on voluntary agreements but sometimes reinforced by planning legislation. At present, a vastly increased pool of skilled professionals and technical resources is available in the context of a rapidly changing medical care system characterized by intense competition, coalescence of services under large managed care plans, and substantial cost pressures. The evidence suggests that, in many areas, these forces have led to the dismantling of regional networks; however, the full potential for these changes to hinder or facilitate access to neonatal intensive care remains to be assessed.

Female

Perinatal regionalization versus hospital competition: the Hartford example.

OBJECTIVES: The increasingly competitive health care environment may undermine effective traditional regional organizations. It is urgent to document the benefits of perinatal regionalization for the emerging health care system. We present a case study that illustrates many of the challenges to and benefits of perinatal regionalization in the 1990s. BACKGROUND: The controversy in Hartford was sparked by a proposed merger of two major pediatric services into a full-service children's hospital. Community hospitals reacted with plans to upgrade their obstetrics/neonatal facilities toward level II (intermediate) or II+ (intensive) neonatal intensive care units (NICUs). The fear that unrestricted competition would drive up overall health care costs prompted the hospital association and Chamber of Commerce to retain consultants to evaluate the number and location of regional NICU beds. METHODS: The consultant team interviewed stake-holders in area hospitals, health maintenance organizations, insurance companies, businesses, state agencies, and community groups, and analyzed quantitative data on newborn discharges. RESULTS: The existing system worked remarkably well for clinical care, training, referrals, and provider and patient satisfaction. There was a high level of inter-hospital collaboration and regional leadership in obstetrics and pediatrics, but strong and growing competition between their hospitals. Hospital administrators enumerated the competitive threats that obligated them to compete and the financial disincentives to support the regional structures. Business leaders and insurance executives emphasized the need to control costs. Analysis of discharge data showed marginal adequacy of NICU beds but maldistribution between NICUs, particularly between level III and level II units. The consultants recommended no new beds based on population projections, declining lengths of stay nationally, and substantial gains available from aggressive back-transport of convalescing infants. The consultants emphasized the need for all stakeholders to support the regional infrastructure (referral, transport, education, evaluation, quality assurance) and to modify competition when it impaired effective regionalization. CONCLUSIONS: Regionalization permits better care at lower cost, yet competition may disrupt this effective system. Active cooperation by stakeholders is vital. Substantial new research is required to define optimal regional organization.

Bed Occupancy

Coagulase-negative staphylococcal bacteremia among very low birth weight infants: relation to admission illness severity, resource use, and outcome.

OBJECTIVE: To examine the impact of admission-day illness severity on nosocomial bacteremia risk after consideration of traditional risk determinants such as birth weight and length of stay. METHODS: The hospital courses for 302 consecutive very low birth weight (less than 1500 g) infants admitted to two neonatal intensive care units were examined for the occurrence of nosocomial coagulase-negative staphylococcal bacteremia. Using both cumulative incidence and incidence density as measures of bacteremia risk, we explored the relation between illness severity (as measured by the Score for Neonatal Acute Physiology [SNAP]) and bacteremia both before and after birth weight adjustment. In addition, the effect of bacteremia on hospital resource use was estimated. RESULTS: Coagulase-negative staphylococcus was the most common pathogen noted in blood cultures drawn at 48 hours after admission or later. It was isolated on at least one occasion in 53 patients (cumulative incidence of 17.5 first episodes per 100 patients). These episodes occurred during 7652 days at risk, giving an incidence density of 6.9 initial bacteremias per 1000 patient-days at risk. As expected, when compared with the nonbacteremic group, bacteremic patients were of lower birth weight (888 +/- 231 vs 1127 +/- 258 g; P < .01) and gestational age (26.4 +/- 2.1 vs 28.9 +/- 2.8 weeks; P < .01). In addition, these patients were more severely ill on admission (SNAP 17.3 +/- 6.5 vs 12.2 +/- 5.8; P < .01). Even after birth weight stratification, the risk of bacteremia by both measures increased with higher SNAP scores. For example, among infants with birth weights greater than 1 kg, 25% of the most severely ill patients (SNAP 20 and higher) experienced at least one bacteremic episode, whereas the rates seen in infants with intermediate (SNAP 10 to 19) and low illness severity (SNAP 0 to 9) were 8.6% and 3.0%, respectively (chi 2 for trend = 7.25; P < .01). Multivariate linear regression showed that bacteremia was associated with a prolongation of neonatal intensive care unit stay of 14.0 +/- 4.0 days (P < .01) and an increase in hospital charges of $25,090 +/- 12,051 (P < .05), even after adjustment for birth weight and admission-day SNAP. CONCLUSIONS: Nosocomial coagulase-negative bacteremia is an important complication among very low birth weight infants. Assessment of illness severity with SNAP provides information regarding nosocomial infection risk beyond that available from birth weight alone.

Bacteremia

CRIB and SNAP.

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Humans

Racial differences in predictive value of the lecithin/sphingomyelin ratio.

OBJECTIVE: Blacks are known to have lower rates of respiratory distress syndrome when rates are adjusted for gestational age and to be more responsive to antenatal glucocorticoid administration compared with nonblacks. These observations have been attributed to acceleration of the timing of lung maturation. An alternative hypothesis is that there are qualitative differences in the surfactants between races. STUDY DESIGN: We reviewed the medical records of a cohort of 702 nonblack and 135 black infants delivered within 72 hours of lecithin/sphingomyelin ratio testing from the presurfactant era and compared respiratory outcome stratified by lecithin/sphingomyelin ratio. RESULTS: Black newborns had less than one third the rate of respiratory distress syndrome (2.2% vs 8.0%, p < 0.01). To adjust for possible differences in maturational timing between races, the results were stratified by lecithin/sphingomyelin ratio. There were no cases of respiratory distress syndrome among black infants with a lecithin/sphingomyelin ratio > 1.2. The protective effect was evident across all strata of lecithin/sphingomyelin ratios (odds ratio 0.25, p = 0.04). Parallel, highly significant reductions in non-respiratory distress syndrome pulmonary morbidity were also noted across all strata of lecithin/sphingomyelin ratios (odds ratio 0.35, p = 0.02). CONCLUSIONS: These differences in the predictive value of the lecithin/sphingomyelin ratio suggest that protection from respiratory distress syndrome must depend on factors independent of the ratio and that these factors differ between races. They also suggest that clinical interpretation of test results may be different between races.

Adult

Estimating neonatal mortality risk: an analysis of clinicians' judgments.

BACKGROUND: Clinicians' estimates of mortality risk in the neonatal intensive care unit (NICU) have implications for patient triage, transfer, initiation and termination of life support, and allocation of medical resources. The accuracy of these judgments has not been studied, nor the differences between nurses and attending physicians. OBJECTIVES: 1) evaluate the accuracy of subjective judgments of NICU unit mortality risk, 2) identify the key components of clinician judgments, 3) compare accuracy between attending physicians and nurses, and 4) examine the utility of combining an objectively computed risk and clinician judgments to improve predictions. METHODS: We obtained estimates of mortality risk on 544 admissions to two NICUs on the day of admission from the attending physician and primary nurse. These were compared with an objective computed mortality risk based on birth weight and the Score for Neonatal Acute Physiology (SNAP) using a linear judgment analysis model, as well as with actual outcomes. RESULTS: Physicians and nurses had good discriminating power with actual mortality rates ranging from 0% among low risk patients to 67% among those with the highest mortality estimates. Physicians had a tendency to overestimate mortality risk. Clinicians base their estimates on the same factors and similar judgment weights as the empiric mortality risk model (22% birth weight, 62% illness severity (SNAP), 13% low Apgar, and 3% for intrauterine growth restriction). Clinicians place additional emphasis on therapeutic as well as physiologic factors. When the computed risk and physician judgment were combined, both made significant contributions in a logistic mortality risk model. CONCLUSIONS: Clinician judgments of mortality risk are fairly accurate and similar to an objective illness severity index. This simple method provides insight into clinical decision making and has important applications in improving direct patient care, appropriate allocation of medical resources, and medical training.

Clinical Competence

Score for Neonatal Acute Physiology: a physiologic severity index for neonatal intensive care.

The substantial variation in birth weight-adjusted mortality among neonatal intensive care units (NICUs) may reflect differences in population illness severity. Development of an illness severity measure is essential for comparisons of outcomes. The Score for Neonatal Acute Physiology (SNAP) was developed and validated prospectively on 1643 admissions (114 deaths) in three NICUs. SNAP scores the worst physiologic derangements in each organ system in the first 24 hours. SNAP showed little correlation with birth weight and was highly predictive of neonatal mortality even within narrow birth weight strata. It was capable of separating patients into groups with 2 to 20 times higher mortality risk. It also correlated highly with other indicators of severity including nursing workload (r = .59), therapeutic intensity (r = .78), physician estimates of mortality risk (r = .65), and length of stay (R2 = .59). SNAP is an important new tool for NICU research.

Birth Weight

Birth weight and illness severity: independent predictors of neonatal mortality.

BACKGROUND: Low birth weight is a major determinant of neonatal mortality. Yet birth weight, even in conjunction with other demographic markers, is inadequate to explain the large variations in neonatal mortality between intensive care units. This variation probably reflects differences in admission severity. The authors have recently developed the Score for Neonatal Acute Physiology (SNAP), an illness severity index specific for neonatal intensive care, and demonstrated illness severity to be a major determinant of neonatal mortality. OBJECTIVE: To define the relative contributions of birth weight and illness severity to the risk of neonatal mortality and to identify other significant independent risk factors. METHODS: Logistic regression was used to analyze data from a cohort of 1621 consecutive admissions to three neonatal intensive care units (92 deaths), to test six alternative predictive models. The best logistic model was then used to develop a simple additive clinical score, the SNAP Perinatal Extension (SNAP-PE). RESULTS: These analyses demonstrated that birth weight and illness severity are powerful independent predictors across a broad range of birth weights and that their effects are additive. Below 750 g, there is an interaction between birth weight and SNAP. Other factors that showed independent predictive power were low Apgar score at 5 minutes and small size for gestational age. Separate derivation and test samples were used to demonstrate that the SNAP-PE is comparable to the best logistic model and has a sensitivity and specificity superior to either birth weight or SNAP alone (receiver-operator characteristic area .92 +/- .02) as well as excellent goodness of fit. CONCLUSION: This simplified clinical score provides accurate mortality risk estimates for application in a broad array of clinical and research settings.

Birth Weight