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B A Yoder

Publications and source records attributed to B A Yoder.

At least 19 recordsLinked to original sources
PubMed1998

Bombesin-like peptide mediates lung injury in a baboon model of bronchopulmonary dysplasia.

The etiology of bronchopulmonary dysplasia (BPD), a chronic lung disease of infants surviving respiratory distress syndrome, remains fundamentally enigmatic. BPD is decreasing in severity but continues to be a major problem in pediatric medicine, being especially prevalent among very premature infants. Increased numbers of pulmonary neuroendocrine cells containing bombesin-like peptide (BLP) have been reported to occur in human infants with BPD. We tested the hypothesis that BLP mediates BPD using the hyperoxic baboon model. Urine BLP levels increased soon after birth only in 100% O2-treated 140-d animals which developed BPD, correlating closely with severity of subsequent chronic lung disease. Similar elevations in urine BLP were observed in the 125-d baboon "interrupted gestation" model of BPD. Postnatal administration of anti-BLP antibody attenuated clinical and pathological evidence of chronic lung disease in the hyperoxic baboon model. Urine BLP could be a biological predictor of infants at risk for BPD, and blocking BLP postnatally could be useful for BPD prevention.

Animals↗
PubMed1998

Early high dose antioxidant vitamins do not prevent bronchopulmonary dysplasia in premature baboons exposed to prolonged hyperoxia: a pilot study.

The antioxidant vitamins ascorbic acid (AA) and alpha-tocopherol (alpha-TP) effectively inhibit oxygen free radical-induced lipid peroxidation. Using a premature baboon model of hyperoxia-induced bronchopulmonary dysplasia (BPD), we measured concentrations of AA, alpha-TP, and conjugated dienes (CD, marker of lipid peroxidation) in four animals (hyperoxic antioxidant group) receiving high dose antioxidant vitamin supplementation (AA, 100 mg x kg x(-1) x d(-1); alpha-TP; 20 mg x kg x(-1) x d(-1)) and one animal receiving standard dose antioxidant vitamin supplementation (AA, 10 mg x kg x(-1) x d(-1); alpha-TP, 1 mg x kg x(-1) x d(-1)). Respiratory and histopathologic data were compared with data from 10 historical animals exposed to hyperoxia (hyperoxic control group) and 11 historical animals treated as required with oxygen (normoxic control group) who had received standard dose antioxidant vitamin supplementation. Compared with standard dose antioxidant vitamin supplementation, high dose antioxidant vitamin supplementation effectively raised AA concentrations in plasma (37 +/- 22 micromol/L and 395 +/- 216 micromol/L, respectively) and tracheal aspirates (62 +/- 35 micromol/L and 286 +/- 205 micromol/L, respectively), and alpha-TP concentrations in plasma (10.1 +/- 2.5 micromol/L and 24.6 +/- 17.5 micromol/L, respectively). However, there was no apparent effect on tracheal aspirate CD concentrations (482 +/- 333 micromol/L and 1050 +/- 1111 micromol/L, respectively), and respiratory parameters in the hyperoxic antioxidant group were comparable to those of the hyperoxic control group but significantly worse than in the normoxic control group. Finally, no protective effect of high dose antioxidant vitamin supplementation was noted at the histopathologic level.

Animals↗
PubMed1997

Oxytocin labor stimulation of twin gestations: effective and efficient.

OBJECTIVE: To test the hypothesis that oxytocin labor stimulation of twin gestations is similar to that of singletons regarding dosage, time, complications, and ability to achieve vaginal delivery. METHODS: This retrospective investigation included 124 gravidas receiving oxytocin for augmentation or induction of labor. Sixty-two women with twin gestations were matched by parity, cervical dilation at initiation of oxytocin, gestational age, oxytocin dosage regimen, and indications for oxytocin to controls with singleton pregnancies. Outcome variables included maximum dosage of oxytocin, incidence of hyperstimulation and fetal heart rate (FHR) abnormalities, time from oxytocin to delivery, cesarean deliveries, and maternal and neonatal outcomes. Statistical analysis was done using McNemar test, paired t test, and Wilcoxon signed-rank test for paired samples. RESULTS: Women with twin pregnancies and those with singletons responded similarly regarding maximum oxytocin dosage (21 +/- 1.5 and 18 +/- 2.4 mU/minute, respectively, P = .1), time from oxytocin to delivery (7.0 +/- 0.8 and 6.7 +/- 0.6 hours, respectively, P = .88), and successful vaginal delivery (90% and 90%, respectively). Oxytocin stimulation of twins resulted in fewer interruptions of the infusion for FHR abnormalities (5% compared with 26%, odds ratio [OR] 0.27, 95% confidence interval [CI] 0.16, 0.47) and hyperstimulation (6% compared with 18%, OR 0.19, 95% CI 0.36, 0.99). CONCLUSION: Twin gestation has no adverse impact on the effectiveness or efficiency of oxytocin labor stimulation. Twin pregnancy seems to be associated with fewer side effects.

Adult↗
PubMed1997

Neonatal outcomes of teenage pregnancy in a military population.

OBJECTIVE: To compare the use of prenatal care, incidence of pregnancy complications, and neonatal outcomes among adolescent mothers with those among older mothers in a military population with equal access to a tertiary care center. METHODS: We reviewed the neonatal data base of a military tertiary care center for the period 1990-1996. All singleton births at least 20 weeks' estimated gestational age (EGA) or with birth weight at least 500 g were included. Maternal transfers were excluded. Mothers were divided into five age groups, with the ranges 13-17, 18-19, 20-24, 25-29, and 30 or more years. Prenatal care was assessed by the Kessner index. Data were analyzed by chi 2 test, t test, Mann-Whitney U test, and logistic regression techniques. RESULTS: Included in the study were 10,168 infants (344 aged 13-17, 893 aged 18-19, 3244 aged 20-24, 3095 aged 25-29, and 2592 aged 30 or more years). There was a greater percentage of Hispanic mothers among adolescents aged 13-17 years (48.3%); this percentage decreased as maternal age increased (32.7% to 14.6%). The percentage of white mothers was greatest for mothers over 30 years old (72.1%), and this percentage decreased as maternal age decreased (70.3% to 35.8%). The percentage of black mothers remained relatively constant in all age groups (12.2-16.0%). There were significant differences in sponsor's rank distribution among groups; mothers 25-29 years old and over 30 years old had higher-paying ranks whereas both teenage groups were of predominantly lower-paying ranks. Gestational age at the first prenatal visit and overall use of prenatal care were significantly improved as maternal age increased for each successive age group. Older mothers had significantly higher rates for diabetes and abnormal fetal sonograms than younger mothers; younger mothers had increased rates for sexually transmitted disease, fetal growth restriction, and tobacco use. Multivariate analysis demonstrated that fetal complications, adequate prenatal care, black maternal race, and lower rank were significant independent risk factors for high-risk outcomes. Young maternal age was not an independent risk factor for prematurity or low birth weight. CONCLUSION: Although adolescent mothers (13-17 years old) used prenatal care less than older mothers, there were no differences in the incidence of prematurity, low birth weight (LBW), or neonatal survival among this group of women cared for in a military tertiary health care setting. In this health care setting, risk for premature birth and LBW are related to complications of pregnancy, maternal race, and lower-paying rank.

Adolescent↗
PubMed1997

Effect of excessive GnRH-binding substance on circulating maternal hCG in human pregnancy.

Gonadotropin-releasing hormone (GnRH) can stimulate the release of placental human chorionic gonadotropin (hCG). Thus, at the onset of these studies it was the objective to define the relationship of hCG to GnRH in the maternal circulation throughout pregnancy, focusing on early pregnancy. Blood samples were collected at 8, 10, 12, 14, 16, 28 and 36 weeks of gestation during labor and the GnRH and hCG levels were determined by radioimmunoassay. Of 39 pregnancies, a GnRH-binding substance was found in the maternal circulation of three. This GnRH-binding substance resulted in erroneous GnRH levels, due to the very high non-specific binding. In the pregnant women without this GnRH-binding substance, GnRH attained highest concentrations at 12-14 weeks. The typical peak of hCG at 8-10 weeks of gestation was observed in this group, while the group of patients having the GnRH-binding substance had significantly lower hCG levels. Each of the patients with circulating GnRH-binding substance had prior pregnancy(s) and two of the three had a prior pregnancy loss. The nature of this GnRH-binding substance was investigated using gel chromatography. After incubation of [125I]GnRH with patient plasma for 3 days this substance was shown to be of high molecular weight which was ethanol precipitable. This binding substance may therefore be an antibody, since it appears to be a high molecular weight protein requiring a number of days to bind the [125I] GnRH. This GnRH-binding substance may be of physiological importance, since the circulating hCG level was significantly less in the group of patients with this substance than in those without.

Adolescent↗
PubMed1996

Circulating maternal corticotropin-releasing hormone and gonadotropin-releasing hormone in normal and abnormal pregnancies.

OBJECTIVE: Corticotropin-releasing hormone and gonadotropin-releasing hormone are produced by the human placenta and have been measured in the maternal circulation during pregnancy. Our objective was to determine concentrations of these substances in maternal plasma throughout normal pregnancies and in early pregnancy loss. STUDY DESIGN: Fifty-one pregnant women were followed up prospectively and plasma samples were drawn at 8, 10, 12, 14, 16, 28, and 36 weeks' gestation and during labor. Specific and sensitive radioimmunoassays were used to determine corticotropin-releasing hormone and gonadotropin-releasing hormone concentrations in these samples. RESULTS: Blood samples were drawn at all time points and outcome data were available from 33 women who completed their pregnancies at term without complications. In this normal group circulating corticotropin-releasing hormone concentrations increased from low or undetectable concentrations at 8 weeks (< or = 23.2 +/- 1.3 pg/ml, mean +/- SEM) to measurable values at 16 weeks (34.3 +/- 2.2 pg/ml). Thereafter there was a significant increase to 1294 +/- 113 pg/ml in labor. Gonadotropin-releasing hormone demonstrated a trimodal distribution, increasing significantly from 8 to 14 weeks, decreasing at 16 weeks, and increasing again by term. The ratio of corticotropin-releasing hormone to gonadotropin-releasing hormone in the normal group demonstrated a 30-fold increase from 8 weeks to term. In eight cases of early pregnancy loss corticotropin-releasing hormone and gonadotropin-releasing hormone concentrations were not significantly different from those of the normal group in early pregnancy. In two cases of premature delivery gonadotropin-releasing hormone concentrations and ratios were within the normal range; corticotropin-releasing hormone levels were normal in both cases of premature delivery. CONCLUSION: In this study we determined maternal concentrations of corticotropin-releasing hormone and gonadotropin-releasing hormone in normal pregnancies and in labor at term. Neither maternal concentrations of corticotropin-releasing hormone nor gonadotropin-releasing hormone were useful in identifying pregnant women at risk for early pregnancy loss.

Abortion, Spontaneous↗
PubMed1996

Volume of blood required to detect common neonatal pathogens.

OBJECTIVE: To determine the minimum volume of blood and the absolute number of organisms required for detection of bacteremia and fungemia by an automated colorimetric blood culture system (BacT/Alert, Organon Teknika). DESIGN: Common neonatal pathogens, Escherichia coli, Streptococcus agalactiae (group B streptococcus (GBS): one American Type Culture Collection (ATCC) strain and one clinical isolate), Staphylococcus epidermidis, and Candida albicans, were seeded into blood to produce bacteremia or fungemia with low colony counts (1 to 3 colony-forming units (CFU) per milliliter) and ultra-low colony counts (<1 CFU/ml). For each organism, 96 culture bottles were inoculated with either 0.25, 0.5, 1.0, or 4.0 ml of the two seeded blood concentrations. Blood culture bottles were incubated in the BacT/Alert device for 5 days, and time to positivity was noted when applicable. All bottles were subcultured on plated media. DATA ANALYSIS: The Poisson statistic was used to calculate the probability of finding at least one viable CFU per inoculated culture bottle. The fraction of culture bottles with positive findings per group was divided by the probability of one or more organisms present to give the positivity index. RESULTS: Plated subculture identified no growth of organisms not detected by the colorimetric detection system. The false-positive rate for the automated device was less than 1%. The positivity index for the GBS clinical isolate was 1.13, for the GBS ATCC isolate 0.96, for S. epidermidis 0.94, for C. albicans 0.97, and for E. coli 0.95. There was a statistically significant difference with time to positivity and inocula volume (p <0.01), but the difference was not clinically important. CONCLUSIONS: If one or two viable colony-forming units are in the blood inoculated into culture media, the BacT/Alert system will detect growth rapidly. Because there appears to be a sizable subset of neonates who are at risk of sepsis with a colony count less than 4 CFU/ml, then a 0.5 ml inoculum of blood into the culture media is inadequate for sensitive and timely detection of bacteremia. One to two milliliters of blood should increase microorganism recovery in the face of low-colony-count sepsis.

Bacteremia↗
PubMed1995

Differentiation of segmented and band neutrophils during the early newborn period.

This prospective study evaluated the degree of inter-reader variability in the identification of segmented and band neutrophils from blood smears of full-term, healthy neonates. Wide inter-reader differences of band neutrophil identification and the immature to total neutrophil ratio were observed. Because of poor correlation between evaluators of the same blood smear, the clinical utility of the manual differential leukocyte count in the evaluation of neonates is limited.

Blood Specimen Collection↗
PubMed1995

Sensitivity and specificity of rapid diagnostic tests for detection of group B streptococcal antigen in bacteremic neonates.

Latex particle agglutination (LPA) testing for antigen to group B streptococcus (GBS) has been useful in the diagnosis of GBS sepsis in newborns. However, recent reports have demonstrated that the sensitivity of LPA assays may be as low as 27 to 54%. The purposes of the present study were to directly compare the abilities of four urine antigen assays to detect GBS antigen with clinical urine samples from neonates with GBS bacteremia and to evaluate the effect of the urine concentration on the sensitivities and specificities of these assays. Urine samples were collected serially from neonates with blood cultures positive for GBS or on admission from healthy full-term infants. One milliliter of urine was removed, and the remainder was concentrated to a volume of 1 ml. Unconcentrated samples were serially diluted with normal saline and were assayed to determine the highest dilution which would produce a positive test result. The Wellcogen, Bactigen, and Directigen LPA tests and ICON immunoassay were directly compared by using concentrated and unconcentrated urine specimens and urine specimens with known titers. A total of 94 urine specimens, including 61 concentrated and 75 unconcentrated specimens, from bacteremic infants were available for sensitivity testing, and 220 urine specimens from uninfected infants were available for specificity testing. There were significant differences in sensitivity among the four assays when they were performed on concentrated urine specimens, as follows: Directigen, 98%; Bactigen, 92%; ICON, 89%; Wellcogen, 68%. When the assays were performed on unconcentrated urine specimens, the Directigen (84%) and Bactigen (76%) assays were each significantly more sensitive than the ICON (59%) or Wellcogen (43%) assay. All four assays were significantly more sensitive in detecting GBS antigen in concentrated than in unconcentrated urine. The Directigen assay detected antigen in higher dilutions (geometric mean titer, 1:5) than the ICON (1:3), Bactigen (1.2), or Wellcogen (1:1) assay. The specificity was 99.5% for all four assays when concentrated urine was used and for the Bactigen, Directigen, and ICON assays when unconcentrated urine was used; the Wellcogen assay was 100% specific when unconcentrated urine was used. We conclude that there are significant differences in sensitivity but not specificity among the commercially available assays for the detection of GBS antigenuria when concentrated and unconcentrated urine specimens are tested. These differences in sensitivity may affect the abilities of clinicians to accurately diagnose GBS sepsis before culture results are available.

Antigens, Bacterial↗
PubMed1995

Predictors of failure of high-frequency oscillatory ventilation in term infants with severe respiratory failure.

OBJECTIVE: To identify clinical factors in term neonates with severe respiratory failure that predict which neonates are unlikely to respond to high-frequency oscillatory ventilation (HFOV). DESIGN: This was a retrospective review of patient charts and medical records. PATIENTS: We studied 190 newborns treated with HFOV between July 1985 and December 1992. All patients were at least 35 weeks' estimated gestational age and had severe respiratory failure, defined as arterial to alveolar oxygen ratio (a/A ratio) of less than 0.2 or the need for peak inspiratory pressure greater than 35 cm H2O on conventional ventilation. RESULTS: Of the 190 patients, 111 (58%) responded to HFOV (HFOV responders), and 79 (42%) were placed on extracorporeal membrane oxygenation (ECMO) after HFOV failed to improve gas exchange (nonresponders). The two groups were similar in gender and birth weight. Factors associated with failure of HFOV to produce a sustained improvement in gas exchange were a diagnosis of congenital diaphragmatic hernia and more severe respiratory compromise as assessed by admission blood gas. Stepwise logistic regression analysis showed that a diagnosis of congenital diaphragmatic hernia/lung hypoplasia (CDH/LH) and the a/A ratio at initiation of and after 6 hours of HFOV were the only significant independent predictors of the need for ECMO. Among all the patients, the presence of CDH/LH or an initial a/A ratio of 0.05 or lower yielded a sensitivity of 74% and specificity of 77% in correctly identifying neonates in whom HFOV failed to produce a sustained improvement in oxygenation. When neonates with CDH/LH were excluded from analysis, the most significant predictor of failure of HFOV was the a/A ratio after 6 hours of HFOV. In neonates without CHD/LH, a 6-hour a/A ratio of 0.08 or lower discriminated responders from nonresponders (ie, treatment with ECMO) with a sensitivity of 77% and specificity of 92%. CONCLUSIONS: In our patients, the presence of CDH/LH, severe respiratory failure (a/A ratio 0.05 or lower) at initiation of HFOV, and lack of improvement in oxygenation (a/A ratio 0.08 or lower after 6 hours of HFOV) were associated with failure of HFOV and treatment with ECMO. This information should help other centers to identify neonates who are at the greatest risk for requiring ECMO support and thus allow prompt transfer to an ECMO center.

Acute Disease↗
PubMed1994

Peripheral leukocyte count and leukocyte indexes in healthy newborn term infants.

PURPOSE: This study was designed to determine normal values for the peripheral leukocyte count and leukocyte indexes in healthy term neonates at a specific time after birth. METHODS: We prospectively enrolled 193 healthy term-gestation neonates with no identifiable perinatal risk factors for sepsis. At 4 hours of age a blood sample was collected by warmed heel stick. An automated Coulter complete blood cell count and a 100-cell manual differential leukocyte count were performed on each sample. The differential count was performed by a single hematopathologist unaware of the clinical status of each infant. Perinatal factors were identified by review of the mothers' and infants' hospital records. RESULTS: The mean ratio of immature to total neutrophils was 0.16 (SD 0.10), and the 10% to 90% range was 0.05 to 0.27. The mean leukocyte count was 24.06 x 10(9)/L (24,060/mm3), and the 10% to 90% range was 16.2 to 31.5 x 10(9)/L (16,200 to 31,500/mm3). Neutropenia, < 1.5 x 10(9)/L (1500/mm3) segmented plus band form neutrophils, was not observed. Of all the perinatal factors studied, only the duration of stage 1 labor was found to be associated with significant elevations in the leukocyte and absolute neutrophil counts. CONCLUSIONS: Previously published normal ranges for leukocyte indexes in healthy newborn infants during the early neonatal period are too restrictive; reference standards should be broadened.

Blood Cell Count↗
PubMed1994

Prospective, randomized comparison of high-frequency oscillation and conventional ventilation in candidates for extracorporeal membrane oxygenation.

OBJECTIVE: To compare the safety and efficacy of high-frequency oscillation (HFO) with conventional ventilation in the treatment of neonates with respiratory failure. DESIGN: We conducted a multicenter, prospective, randomized trial. Patients were stratified according to pulmonary diagnosis and then were randomly selected for conventional ventilation or HFO. A balanced crossover design offered patients who met criteria of treatment failure a trial of the alternative mode of ventilation. SETTING: Four tertiary, level 3 neonatal intensive care units accepting regional referrals for extracorporeal membrane oxygenation. PATIENTS: Neonates were eligible for enrollment if their gestational age was > 34 weeks, their birth weight was > or = 2 kg, they were < 14 days of age, they required fractional inspired oxygen > 0.50 and a mean airway pressure > 0.98 kPa (10 cm H2O) to support adequate oxygenation, and they required a peak inspiratory pressure > 2.9 kPa (30 cm H2O) and a rate > 40 breaths per minute to support adequate ventilation. Exclusion criteria were lethal congenital anomalies, profound shock, need for cardiopulmonary resuscitation, and failure to obtain consent. MAIN RESULTS: Of 79 patients studied, 40 were assigned to conventional ventilation and 39 to HFO. Neonates randomly assigned to HFO required higher peak pressure (3.8 +/- 0.5 vs 3.3 +/- 0.8 kPa, 39 +/- 5 vs 34 +/- 8 cm H2O; p = 0.004) and more often met extracorporeal membrane oxygenation criteria (67% vs 40%; p = 0.03) at study entry than did those given conventional ventilation. Twenty-four patients (60%) assigned to conventional ventilation met treatment failure criteria compared with 17 (44%) of those assigned to HFO (not significant). Of the 24 patients in whom conventional ventilation failed, 15 (63%) responded to HFO; 4 (23%) of the 17 in whom HFO failed responded to conventional ventilation (p = 0.03). There were no differences between the two groups with respect to outcome, need for extracorporeal membrane oxygenation, or complications. CONCLUSIONS: We conclude that HFO is a safe and effective rescue technique in the treatment of neonates with respiratory failure in whom conventional ventilation fails.

Extracorporeal Membrane Oxygenation↗
PubMed1994

Meconium-stained amniotic fluid and respiratory complications: impact of selective tracheal suction.

OBJECTIVE: To determine prospectively the incidence of several pulmonary diagnoses among infants born through clear or meconium-stained amniotic fluid (AF) managed by a selective approach to tracheal intubation. METHODS: All live births greater than 36 weeks' gestation occurring between January 1990 and December 1992 were included. Diagnostic criteria for several respiratory disorders were determined prospectively and monitored. Infants with light meconium and vigorous infants with moderate to thick meconium were selectively not suctioned. A control group of infants with clear AF matched for gestational age and year of birth was randomly selected for comparison. The incidence and severity of respiratory disease were compared between the groups. RESULTS: Of 4938 live births, 799 (16%) had meconium-stained AF (light, 334; moderate to thick, 465). Compared to 211 infants with moderate to thick meconium selectively not suctioned, 196 suctioned infants had significantly greater rates of abnormal fetal heart rate (FHR) patterns, fetal acidosis, low Apgar scores at 5 minutes, need for resuscitation, and neonatal intensive care unit admission. Meconium aspiration syndrome was significantly more common in suctioned infants as compared to those selectively not suctioned, those with light meconium, and those with clear fluid (11 versus 3 versus 0 versus 0%; P < .01). The need for ventilator or oxygen support was similar between infants with clear fluid, lightly stained fluid, and moderate to thick fluid who were selectively not suctioned, but was significantly greater among suctioned infants (P < .01). CONCLUSIONS: We conclude that a selective approach to tracheal intubation and suction of infants with meconium-stained AF was not associated with increased pulmonary morbidity or mortality. Postnatal management of neonates at greatest risk of meconium aspiration syndrome does not necessarily prevent adverse pulmonary outcome.

Amniotic Fluid↗
PubMed1993

Effect of maternal race on outcome of preterm infants in the military.

Previous studies suggest that low birth weight black infants have less morbidity and birth-weight-specific mortality during the perinatal period than low birth weight white infants. We studied the effect of maternal race on outcome in preterm infants born at a military hospital that offers free access to obstetric and neonatal care. Between January 1, 1986, and December 31, 1991, data were prospectively collected on all 667 infants delivered at Wilford Hall USAF Medical Center with an estimated gestational age of less than 35 weeks. Three hundred ninety-two white infants and 165 black infants were included in the data analysis. The mean (+/- SD) birth weight was 1701 +/- 65 g for white infants and 1462 +/- 66 g for black infants. The mean estimated gestational age was 31.0 +/- 3.2 weeks for white infants and 29.9 +/- 3.8 weeks for black infants. Preeclampsia was more frequent in black mothers than in white mothers for the entire study population (21% vs 14%), but the birth weight differential between races remained after correction for preeclampsia. There were no significant differences between races in stillbirths, gender, maternal age, maternal transfer status, number of prenatal visits, or percentages of mothers with small-for-gestational-age infants, multiple-gestation infants, prolonged rupture of membranes, or initial prenatal visit during the first trimester. Intraventricular hemorrhage was more frequent in white infants at 27 through 29 weeks estimated gestational age (50% vs 13%). There were no significant differences between the two groups in survival or in the occurrence of severe intraventricular hemorrhage or bronchopulmonary dysplasia.(ABSTRACT TRUNCATED AT 250 WORDS)

Birth Weight↗
PubMed1992

Long distance perinatal transport.

Mortality, incidence of intraventricular hemorrhage (IVH), and complications were evaluated in a perinatal transport system involving patient movement over distances from 1500 to 3700 km over a 3-year period. Of 179 transports, 60% involved neonatal transport, and 58% of the transports involved infants delivering at 32 weeks' gestation or less. Mortality rates were similar between inborn, maternal, and neonatal transports with a trend toward improved survival in all inborn infants 1000 gm or less at birth. IVH occurred in 32% of infants 32 weeks or less gestation; a higher incidence of grades III/IV bleeding were seen in transported infants between 1001 and 2000 gm compared with maternal transports and all inborn infants. Complications occurred in 20% of transports. The frequency of complications were significantly lower when transport was accomplished by the Level III team. In utero transport of selected high-risk pregnancies is preferred despite the ability to provide safe, effective transport of ill neonates over extremely long distances.

Birth Weight↗
PubMed1992

Frequency of chronic lung disease in infants with severe respiratory failure treated with high-frequency ventilation and/or extracorporeal membrane oxygenation.

OBJECTIVE: To assess the frequency of chronic lung disease and factors associated with its development in term infants with severe respiratory failure who receive high-frequency oscillatory ventilation, or high-frequency oscillatory ventilation, and extracorporeal membrane oxygenation (ECMO). DESIGN: Retrospective review of pulmonary outcome of all ECMO candidates admitted to Wilford Hall USAF Medical Center between July 1985 and September 1989. SETTING: A tertiary, level III, neonatal ICU accepting regional referrals for high-frequency ventilation and ECMO. PATIENTS: Ninety-four patients who were candidates for ECMO were studied. High-frequency oscillatory ventilation alone was used in 48 infants. Forty-six infants were treated with high-frequency oscillatory ventilation and ECMO. MAIN RESULTS: Twenty (24%) of 84 survivors developed chronic lung disease. There were no differences in gestational age, birth weight, or gender between those infants who developed chronic lung disease and those infants who did not. Arterial blood gas and ventilatory settings at initiation of high-frequency oscillatory ventilation were similar between those infants who did and those who did not develop chronic disease. Patients who developed chronic lung disease more often had lung hypoplasia (40% vs. 5%) and more often required ECMO (75% vs. 39%) than those patients who did not. In patients without lung hypoplasia, those patients who developed chronic lung disease were older at initiation of high-frequency oscillatory ventilation rescue than those patients who did not develop chronic lung disease (median 91 vs. 46 hrs). CONCLUSIONS: The frequency of chronic lung disease in ECMO candidates is clinically important. Factors associated with chronic lung disease in ECMO candidates are: the presence of lung hypoplasia, delayed referral, and the need for ECMO to support gas exchange.

Birth Weight↗