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S B Korones

Publications and source records attributed to S B Korones.

At least 55 records · Page 3Linked to original sources
PubMed1992

Early and late intraventricular hemorrhage: the role of obstetric factors.

OBJECTIVE: To evaluate the influence of active phase labor and other obstetric factors on the development of periventricular-intraventricular hemorrhage in the neonate. METHODS: A total of 230 infants were studied. Antenatal enrollment was carried out when estimated fetal weight was 1750 g or less. Serial head ultrasound scans were performed to screen for periventricular-intraventricular hemorrhage, with the initial scan performed within minutes of birth. Scan findings and obstetric and neonatal variables collected prospectively at scheduled intervals were analyzed to determine the significant factors that predispose to intraventricular hemorrhage. RESULTS: In 47 infants (20%), intraventricular hemorrhage was detected within 1 hour of birth (early) and in another 49 (21%) at a later age (late). The overall incidence of hemorrhage was similar between vaginal and cesarean deliveries (41 and 44%, respectively). Early hemorrhage was more frequent in vaginal (28%) than cesarean deliveries (11%), whereas late hemorrhage was more frequent in cesarean deliveries. When the role of delivery mode and labor was analyzed by stepwise logistic regression, the odds ratios for development of early intraventricular hemorrhage increased in the following order: cesarean delivery with no labor, cesarean delivery with latent phase labor, vaginal delivery with forceps use, cesarean delivery with active phase labor, and vaginal delivery without forceps use. For late hemorrhage, the odds ratios increased in the following order: vaginal delivery with forceps, vaginal delivery without forceps, cesarean delivery with no labor, cesarean delivery with latent phase labor, and cesarean delivery with active phase labor. CONCLUSIONS: Active phase labor may predispose to early periventricular-intraventricular hemorrhage, but its influence may be attenuated by use of forceps or by abdominal delivery. The protective effect of forceps remains for late periventricular-intraventricular hemorrhage, but abdominal delivery does not seem to protect against late hemorrhage.

Cerebral Hemorrhage↗
PubMed1991

Necrotizing enterocolitis in very low birth weight infants: biodemographic and clinical correlates. National Institute of Child Health and Human Development Neonatal Research Network.

We studied the occurrence of necrotizing enterocolitis in 2681 very low birth weight infants during an 18-month period to characterize the biodemographic and clinical correlates. Proven necrotizing enterocolitis (Bell stage II and beyond) occurred in 10.1% of study infants; necrotizing enterocolitis was suspected in 17.2% of study infants. Positivity of blood cultures was related to necrotizing enterocolitis staging. The mortality rate increased only for stage III necrotizing enterocolitis (54% died). Logistic regression identified medical center of birth, race, gender, birth weight, maternal hemorrhage, duration of ruptured membranes, and cesarean section as significant risk factors. For one center the odds ratio was 3.7, whereas for another center it was only 0.3. For black boys, the odds ratio was 2.3 relative to nonblack boys; for girls, race did not affect prevalence of necrotizing enterocolitis. Age at onset was related to birth weight and gestational age. Intercenter differences in necrotizing enterocolitis prevalence were related to time required to regain birth weight and other indicators of fluid management. Gram-positive organisms predominated in positive blood cultures for stage I and II necrotizing enterocolitis; enteric bacteria were isolated more frequently in infants with stage III disease. We conclude that necrotizing enterocolitis prevalence varies greatly among centers; this may be related to early clinical practices of neonatal care.

Birth Weight↗
PubMed1991

Acute phase reactants in neonatal bacterial infection.

The C-reactive protein (CRP) level was evaluated in 142 infants requiring investigation for suspected infection. After excluding two neonates because of incomplete data, there remained 140 neonates, of whom 16 had septicemia. Fifteen of 16 had increased CRP levels. The CRP value was not elevated in any baby (n = 5) who had positive blood cultures for Staphylococcus epidermidis, all of whom had an uneventful clinical course. The CRP level was elevated in all six babies with meconium-aspiration syndrome, but was normal in five infants whose viral cultures were positive. Ninety-nine percent of uninfected babies had normal CRP values. Overall, CRP was a valuable test for diagnostic confirmation of bacterial infection. Elevated CRP level was always accompanied by at least one abnormality in the other tests performed. Although the study was not intended to predict clinical onset of bacterial disease, our results suggest that the CRP level, because of a high negative predictive value, may be useful in ruling out bacterial infection.

Acute-Phase Proteins↗
PubMed1990

Frequent handling in the neonatal intensive care unit and intraventricular hemorrhage.

The association between periventricular-intraventricular hemorrhage (PV-IVH) and frequent handling resulting from various neonatal intensive care procedures and routine interventions was evaluated in a prospective clinical study. Inborn premature babies with birth weight less than or equal to 1500 gm (n = 156) who did not have PV-IVH or who had grade 1 PV-IVH at less than or equal to 1 hour were randomly assigned to the reduced manipulation protocol (n = 62) or to standard care (n = 94). A bedside microcomputer-based data acquisition system was used to monitor the duration of rest or the number of interventions per day. Infants assigned to receive reduced manipulation spent a significantly higher percentage of time each day at rest than did those who received standard manipulation (p less than 0.006). However, the incidence of grades 2 to 4 PV-IVH did not differ significantly (30% in the study vs 37% in the standard manipulation group). When we analyzed the effect of manipulation in relation to risk of PV-IVH, while taking into account other perinatal variables, standard manipulation was not associated with increased risk of grades 2 to 4 PV-IVH. However, low birth weight, maternal smoking, general anesthesia, early grade 1 PV-IVH, low hematocrit, lowest arterial oxygen pressure within the first 6 hours of life, and large base deficit at 6 hours of age all increased the relative risk of grades 2 to 4 PV-IVH.

Cerebral Hemorrhage↗
PubMed1990

Mean arterial blood pressure changes in premature infants and those at risk for intraventricular hemorrhage.

Bedside microcomputer-derived, minute-to-minute mean arterial pressure (MAP) values during the first 48 hours of life were studied in 100 preterm babies with birth weight less than or equal to 1500 gm. In those babies (n = 72) with no periventricular-intraventricular hemorrhage (PV-IVH) or with grade 1 PV-IVH, the MAP values increased during the study period, with minute-to-minute variation and interval undulation. The MAP values in those with birth weight greater than 1000 gm were higher than in those of lower birth weight. Infants in whom grades 2 to 4 PV-IVH developed (n = 28) had consistently lower MAP values during the study period. Minute-to-minute variability, expressed as the average of the coefficients of variation at 15-minute intervals, did not differ between birth weight groups, nor did they differ between the PV-IVH group and their matched control subjects. However, those with PV-IVH spent a greater percentage of time, with a coefficient of variation greater than or equal to 13% or less than 3%, than their matched control subjects spent (p less than 0.005). This study provides reference data for MAP changes in premature babies. The observed MAP changes in those with PV-IVH lend support to a significant role for MAP alterations in the pathogenesis of PV-IVH.

Blood Pressure↗
PubMed1990

Blood pressure increases, birth weight-dependent stability boundary, and intraventricular hemorrhage.

The blood pressure (BP) and transcutaneous PO2 (TcPO2) changes associated with intensive care procedures were evaluated to determine whether responses differ between babies with and without periventricular-intraventricular hemorrhage (PV-IVH). Fifty-three inborn babies less than or equal to 1500 g were studied using a microcomputer-based monitoring system. With almost any procedure including a seemingly benign one such as a diaper change, peak systolic BP increased and TcPO2 decreased. However, responses to interventions did not differ between babies with PV-IVH and those without PV-IVH. Neither did these responses differ between those with birth weight less than or equal to 1000 g and greater than 1000 g. When each baby's record was scanned for the highest peak systolic BP before diagnosis of PV-IVH or within 48 hours in those with no PV-IVH and their BP points plotted against birth weight, a stable region was evident wherein PV-IVH occurred at a lower incidence (13%). When peak systolic BP was beyond this stable region, the incidence of PV-IVH was significantly higher, 70% (P less than .0001). The stability boundary for the maximum systolic BP is birth weight-dependent; the limit for the highest tolerable peak systolic BP is lower for the low-birth-weight infant. In over 70% of instances the highest peak systolic BP was associated with motor activities either induced by nursery procedures or spontaneous. We speculate that decreasing the frequency of intensive care interventions may decrease episodic BP increases to levels beyond the birth weight-dependent stability boundary where PV-IVH is likely to occur.

Birth Weight↗
PubMed1989

Indomethacin reduces the risks of severe intraventricular hemorrhage.

A prospective, random selection, double-blind clinical trial was carried out to determine the efficacy of indomethacin in preventing periventricular-intraventricular hemorrhage (PV-IVH). Babies who were born in our institution, had birth weights less than or equal to 1500 gm, and had no PV-IVH or grade 1 PV-IVH were given either placebo (n = 70) or indomethacin (n = 71), 0.2 mg/kg intravenously at 6 hours of age and 0.1 mg/kg at 18 and 30 hours. Two major outcomes were determined: the development of grades 2 to 4 PV-IVH and the development of severe PV-IVH (i.e., hemorrhages with blood filling greater than 50% of the ventricles and in some cases with associated parenchymal echodensities). Grades 2 to 4 PV-IVH occurred in 16 (23%) of the indomethacin group and 27 (39%) of the placebo group (p less than 0.03). The incidence of severe PV-IVH was 3% in the indomethacin-treated babies and 14% in the control group (p less than 0.02). The influence of other perinatal factors on the incidence of grades 2 to 4 or severe PV-IVH was determined by stepwise logistic regression. Placebo use, early grade 1 PV-IVH, lower birth weight, and higher fraction of inspired oxygen at 6 hours of life were associated with higher estimated odds of the development of grades 2 to 4 PV-IVH. Placebo use, male gender, lower 5-minute Apgar score, and a large base deficit were predictive of severe PV-IVH. Estimated odds ratios of severe PV-IVH with placebo use and male gender were 11.25:1 and 9:1, respectively. Thus indomethacin prophylaxis reduced the relative risk of grades 2 to 4 PV-IVH and severe PV-IVH, but other perinatal variables contributed significantly to the overall risk of PV-IVH.

Apgar Score↗
PubMed1989

Necrotizing enterocolitis: improving survival within a single facility.

Necrotizing enterocolitis (NEC), a disease associated with prematurity, carries a significant morbidity and mortality. This study was designed to evaluate our progress in dealing with NEC both medically and surgically in a single large neonatal intensive care unit (NICU). We also sought to confirm the relation of birth weight and particular indications for operation to outcome. Over 6 1/2 years, there were 7,807 admissions to a large NICU. Though there has been a steady increase in total admissions, especially of infants weighing less than 1,000 gm, survival has improved significantly in all groups (mean 89.1%). NEC occurred in 358 infants (4.6%), and 115 (32%) required surgical intervention. Infants weighing between 751 and 1,000 gm had the highest incidence of NEC. There has been a significant decrease in the mortality of both medically and surgically treated infants with NEC; in both cases, this decrease is weight-dependent. We found that using erythema and edema of the abdominal wall and a fixed-loop roentgenographic pattern as early indicators of necrotic bowel significantly improves survival in surgically treated infants.

Acute Disease↗
PubMed1988

The relationship between labor and route of delivery in the preterm infant.

The purpose of this prospective study was to evaluate the effects of the active phase of labor and route of delivery on the frequency of germinal layer/intraventricular hemorrhage in 89 infants with ultrasound-estimated fetal weights less than or equal to 1750 gm. Twenty-eight infants (31.5%) had germinal layer/intraventricular hemorrhage within 1 hour after birth and an additional 15 infants (17%) had germinal layer/intraventricular hemorrhage beyond 1 hour after birth. Infants with germinal layer/intraventricular hemorrhage had a significantly lower gestational age (p less than 0.003) and birth weight (p less than 0.007). Germinal layer/intraventricular hemorrhage within 1 hour after delivery was increased in the infants of women who experienced the active phase of labor regardless of the route of delivery. However, the incidence of germinal layer/intraventricular hemorrhage beyond 1 hour after delivery and the overall incidence were similar in the vaginal delivery and cesarean delivery groups. In addition, there was an increased incidence of progression to grades III and IV hemorrhage regardless of route of delivery in the infants whose mothers experienced the active phase of labor.

Apgar Score↗
PubMed1988

Effect of antenatal dexamethasone on neonatal leukocyte count.

The leukocyte count and differential white blood cell count during the first hour of life was determined in 164 neonates born of mothers receiving antenatal steroids and compared to 171 neonates of mothers randomly assigned to a placebo group. A leukemoid reaction (greater than 40,000 WBC/mm3) was seen only once each in the neonates born of placebo or steroid treated mothers. In addition, maternal steroid treatment had no general effect, except in a small subgroup of neonates born 3 to 7 days after the mother had been treated with 20 mg dexamethasone, where the total leukocyte and the absolute neutrophil counts were higher than the placebo group and other subgroups.

Analysis of Variance↗
PubMed1988

Uncommon virus infections of the mother, fetus, and newborn: influenza, mumps and measles.

The literature contains reports of epidemics of varying sizes, which in the aggregate suggest that congenital malformations are not attributable to maternal measles infection during pregnancy, that the incidence of prematurity may be somewhat higher among infected mothers, and that the incidence of abortion also may be somewhat higher. Before the introduction of measles vaccine in this country, the universality of childhood experience rendered adult infection a rare event. Gestational measles was thus uncommon. With the introduction of measles vaccine, these numbers can be expected to have decreased substantially.

Congenital Abnormalities↗
PubMed1988

Indwelling umbilical arterial catheter: a preferred sampling site for blood culture.

Indwelling umbilical arterial catheter was evaluated prospectively as an alternative site for blood culture sampling. In 282 infants, 318 paired blood cultures were obtained from the peripheral vein and from the indwelling umbilical arterial line. Duration of umbilical catheter placement ranged from 0.5 to 196 hours; in 17% of the infants, catheters were in place for between 24 and 196 hours. In 13 blood culture pairs the same pathogens were found and had been obtained from the peripheral vein and the umbilical arterial line. Two pairs were positive for discrepant organisms. A total of 11 pairs were positive in one site only, with five positive from peripheral vein only and the other six from the umbilical arterial catheter. However, most of these single-site positive blood cultures were apparently true positives based on supporting laboratory data for infection. Contamination rates were 1.3% and 0.9% for peripheral vein and umbilical arterial catheter blood cultures, respectively. Thus, in sick neonates, the indwelling umbilical arterial line was an alternative and perhaps a preferred site for blood culture sampling.

Blood↗
PubMed1986

Partial plasma exchange transfusion improves cerebral hemodynamics in symptomatic neonatal polycythemia.

Cerebral arterial pulsatile flow changes and the effect of partial plasma exchange transfusion on these pulsatile flow patterns were studied in neonatal polycythemia/hyperviscosity syndrome by transcutaneous Doppler technique. Twenty-two infants with cord blood hematocrit greater than 58% (greater than 2 SD above the mean) were studied from a total of 2,400 infants who were screened for cord hematocrit over a 6-month period. Each of 22 infants had the following initial studies: radial artery hematocrit, viscosity, intracranial pressure measurement, and anterior cerebral arterial Doppler study to determine pulsatility index, mean systolic, mean end diastolic, and mean flow velocities, and area underneath the curve of the velocity tracings/min. Twelve of 22 infants had radial artery hematocrit less than 63%, were normoviscous (less than 13.5 cps, 11.25 sec-1) and were designated as control infants. Ten (study infants) were polycythemic (hematocrit greater than or equal to 63%) and hyperviscous (greater than or equal to 13.5 cps, 11.25 sec-1). All study patients were treated by partial plasma exchange transfusion. Initial studies were repeated after exchange transfusion. Control infants were not treated. Prior to exchange procedure, the polycythemic hyperviscous infants had significantly higher hematocrit, viscosity, and pulsatility index; the other Doppler measurements and heart rate were lower than those of control babies. The exchange procedure resulted in significantly decreased hematocrit, viscosity, and pulsatility index and increase in the other Doppler measurements, heart rate, and intracranial pressure. All postexchange measurements of study infants were not statistically different from the control infants. These data suggest that neonatal polycythemia/hyperviscosity syndrome may be associated with abnormal cerebral hemodynamics that could improve with partial plasma exchange transfusion.

Blood Viscosity↗
PubMed1984

Obstetric factors and relative risk of neonatal germinal layer/intraventricular hemorrhage.

One hundred fifty-five inborn infants with a birth weight less than or equal to 1,500 gm were prospectively evaluated for germinal layer/intraventricular hemorrhage. Maternal characteristics, obstetric factors, and neonatal condition in the immediate newborn period were analyzed as possible risk factors for germinal layer/intraventricular hemorrhage. Early germinal layer/intraventricular hemorrhage or hemorrhages identified during the first 24 hours of life were observed in 85 (55%) of these infants. Another 37 (24%) had germinal layer/intraventricular hemorrhage after 24 hours of age (late germinal layer/intraventricular hemorrhage). None of the maternal and obstetric variables, including labor, mode of delivery, and presentation, appeared to increase the risk of germinal layer/intraventricular hemorrhage. The immediate neonatal condition, birth weight, gestational age, and intrauterine growth, all influenced the occurrence of germinal layer/intraventricular hemorrhage, especially early germinal layer/intraventricular hemorrhage. We suggest that future studies to investigate the role of maternal or obstetric factors in the pathogenesis of germinal layer/intraventricular hemorrhage should discriminate early from late germinal layer/intraventricular hemorrhage. Obstetric factors are more likely to influence the early onset of germinal layer/intraventricular hemorrhage; their effect, if any, becomes less discernible later.

Anesthesia, Obstetrical↗
PubMed1984

Heat shield reduces water loss.

A heat shield covered by polyvinyl chloride film greatly reduced insensible water loss and radiant energy requirements in 12 preterm infants on a radiant cradle. Measured transmittance of radiant energy emitted by the radiant heater was impeded minimally by various thin film plastics but was blocked significantly by Perspex.

Body Temperature↗
PubMed1984

A decreased incidence of necrotizing enterocolitis after prenatal glucocorticoid therapy.

In a large multicentered, collaborative randomized and blinded trial utilizing antenatal corticosteroids, the goals included determining the effectiveness of these agents in accelerating lung maturation, as well as monitoring any short-term or long-term adverse effects of this treatment on the parturient, fetus, and/or infant. More than 100 specific items, pertaining to diagnoses, complications, and outcomes were recorded for the 696 mothers enrolled in the study and their 745 infants. A significantly decreased incidence of necrotizing enterocolitis (P = .002) was found in the infants treated with steroids. The possibility of accelerated intestinal maturation induced by antenatal maternal steroid therapy exists. This treatment regimen is particularly attractive as adverse aspects of steroid therapy at the dosage utilized have not been demonstrated.

Clinical Trials as Topic↗