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B A Yoder

Publications and source records attributed to B A Yoder.

31 records · Page 2Linked to original sources
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↗
PubMed1990

Changes in the differential white blood cell count in screening for group B streptococcal sepsis.

We compared several previously defined scoring systems using white blood cell indices as part of a retrospective evaluation of infants with early onset Group B streptococcal (GBS) sepsis. Nineteen newborns were diagnosed with GBS sepsis between January, 1988, and April, 1990. Case controls (n = 33) were selected from patients admitted to the Neonatal Intensive Care Unit for suspected sepsis. Complete blood counts obtained at admission and between 12 and 24 hours of age were reviewed. There was a significant change in the ratio of immature to total neutrophils in the GBS group over time. Scoring systems for neonatal sepsis by Manroe et al., Rodwell et al. and Spector et al. had poor sensitivity, specificity, positive predictive value and negative predictive value when initial white blood cell count criteria were used, but scoring systems by Manroe and Rodwell were 100% sensitive and had 100% negative predictive value when applied to the repeat white blood cell count. We conclude that a single early complete blood count may not be an adequate screening tool for early onset GBS sepsis and should not be used to rule out infection. Optimal screening for GBS sepsis requires a repeat complete blood count within the first 24 hours of age.

Female↗
PubMed1987

Patent ductus arteriosus during high-frequency ventilation for hyaline membrane disease.

The cardiovascular effects of a patent ductus arteriosus (PDA) in a premature baboon model of hyaline membrane disease treated with conventional positive-pressure ventilation (CPPV) or high-frequency ventilation (HFV) were studied. Twenty-seven (84%) of 32 infant baboons delivered at 75% gestation had positive retrograde aortograms at one hour of life. Eleven (34%) of these infant baboons had persisting evidence for retrograde flow over the first 24 h by Doppler examination. Significantly higher fluid requirements and bicarbonate requirements were present in the animals with a persisting PDA. Mean aortic BP values were significantly lower in these same animals. No significant differences were found between groups when mean airway pressure, heart rate, urine output, or form of ventilation were compared. The only significant differences found between the conventional and high-frequency ventilated animals with PDA were higher peak airway pressures and lower PEEP levels in the conventionally ventilated infants. The premature baboons can be a useful primate model to study the PDA. There appears to be no significant difference regarding the clinical effects of HFV and CPPV on PDA.

Acidosis↗
PubMed1986

Pulmonary interstitial emphysema treated by high-frequency oscillatory ventilation.

Twenty-seven low birth weight infants who developed pulmonary interstitial emphysema (PIE) and respiratory failure while on conventional ventilation were treated with high-frequency oscillatory ventilation (HFOV). The mean birth weight was 1.2 kg (range 0.55 to 2) with gestational age of 28 wk (range 25 to 34). Ten patients died, six of whom had documented sepsis with shock and were therefore excluded from analysis. All patients showed initial improvement on HFOV. Surviving patients showed continued improvement in oxygenation and ventilation at increasingly lower fraction of inspired oxygen and proximal airway pressure with resolution of PIE, while nonsurvivors progressively developed chronic respiratory insufficiency with continued PIE from which recovery was not possible. Overall survival in nonseptic patients was 80% (16 of 20). We found HFOV to be effective in the treatment of PIE and hypothesize that interstitial airleak is decreased during HFOV because adequate ventilation is provided at lower peak distal airway pressures.

Critical Care↗
PubMed1985

Survival and short-term morbidity of the premature neonate.

Obstetric decisions regarding premature (23 to 32 weeks' gestation) infants must be based on gestational age. However, most reports of the survival of premature infants are based on birth weight. The present report relates the perinatal survival and morbidity of 105 newborns to the obstetric gestational dating criteria between 23 and 32 weeks' gestation. Gestational age was determined from at least four obstetric criteria including the first day of the last menstrual period, early pelvic examination, the earliest auscultation of fetal heart tones with a fetoscope, fundal height measurements in centimeters between 20 and 30 weeks' gestation, and sonographic gestational age measurements. At 23 to 26 weeks' gestational age, nine (39%) of 23 neonates survived. Five of nine survivors had moderate to severe intracranial hemorrhage, three had moderate to severe bronchopulmonary dysplasia, and three had moderate to severe retrolental fibroplasia. At 27 to 29 weeks' gestational age, 25 (93%) of 27 neonates survived. Of the 25 survivors, three had moderate to severe intracranial hemorrhage, one had moderate to severe bronchopulmonary dysplasia, and one had severe retrolental fibroplasia. At 30 to 32 weeks' gestational age, 52 (95%) of 55 neonates survived. Three of the 52 (6%) survivors had serious neonatal morbidity consisting of moderate to severe intracranial hemorrhage (three neonates) and moderate to severe bronchopulmonary dysplasia (one neonate). Thus, ten of 34 (29%) survivors between gestational ages of 24 to 29 weeks had a serious morbidity versus only three of 52 (6%) survivors between 30 to 32 weeks' gestation (P less than .01).

Bronchopulmonary Dysplasia↗
PubMed1984

High-frequency ventilation compared to conventional positive-pressure ventilation in the treatment of hyaline membrane disease in primates.

High-frequency ventilation (HFV) has been suggested as an alternative to conventional positive-pressure ventilation (PPV) in the treatment of infants with hyaline membrane disease (HMD). Using a previously validated primate model of HMD, 15 baboon fetuses were delivered at 75% of gestation and randomly assigned to 1 of 3 ventilator treatment groups: PPV, HFV delivered by an oscillator (HFO), or HFV delivered by a flow interrupter (HFFI). All animals had clinical and radiographic evidence of HMD. At 96 h of life, all animals were sacrificed and clinical and pathologic findings were analyzed. During the first 10 h of the experiment, the HFO animals required higher mean proximal airway pressures than either the HFFI or PPV groups. However, both the HFFI and HFO animals had higher PaO2/PAO2 ratios than the PPV controls, suggesting earlier saccular recruitment. Thus, HFV is as effective as PPV in the treatment of HMD in baboons. Whether it will decrease the risk of bronchopulmonary dysplasia is not known.

Animals↗
PubMedDate not supplied

ECMO for left ventricular assist in a newborn with critical aortic stenosis.

Extracorporeal membrane oxygenation (ECMO) has been used in neonates for a variety of disease states including congenital diaphragmatic hernia, meconium aspiration syndrome, sepsis, and postoperative cardiac compromise. To our knowledge, ECMO has not been employed prior to cardiac catheterization in critical aortic stenosis (CAS). We report a neonatal case of CAS where ECMO was used early as a form of left ventricular assist to achieve adequate systemic perfusion and oxygenation and reduce myocardial ischemia. The patient was maintained on ECMO during subsequent attempts at cardiac catheterization, balloon valvuloplasty, and operative valvotomy.

Aortic Valve↗
PubMedDate not supplied

Failure of intrapartum antibiotics to prevent culture-proved neonatal group B streptococcal sepsis.

Early-onset group B streptococci (GBS-EOS) sepsis may be prevented by intrapartum antibiotics administered for GBS maternal colonization, premature labor, or prolonged rupture of membranes. We sought to identify cases of neonatal GBS sepsis after apparent failure of intrapartum chemotherapy and to determine the factors associated with failure of intrapartum antibiotics in these cases. We identified 96 GBS blood culture-positive infants at five military medical centers from 1987 to 1990. Eighteen (18.7%) of these infants had mothers who had received intrapartum antibiotics; 16 of 18 cases were early-onset disease, 15 of which initially had symptoms at less than 1 hour of age. Two infants had late-onset disease develop at 3 weeks of age. At least one perinatal risk factor (prematurity, prolonged rupture of membranes > 12 hours, maternal fever) was present in each of the 16 cases. Indications for intrapartum antibiotics were suspected chorioamnionitis (13 cases), GBS colonization and prolonged rupture of membranes or prematurity (3), and GBS colonization alone (2). Maternal antibiotics included ampicillin (14 cases), cephadyl (1), vancomycin (1), clindamycin (1), and gentamicin alone (1). The median number of doses of ampicillin before delivery was 1 (range, 1 to 21), which was administered at a median of 4 hours (range, 1 to 84) before birth. The mean dose of ampicillin was 1.8 gm/dose (range, 1 to 2 gm/dose). Two of 16 (12.5%) infants with GBS-EOS died as a result of GBS sepsis. In our population of neonates with GBS-EOS, 18.4% (16 of 87) of the infants had positive blood cultures despite intrapartum antibiotics. Intrapartum antibiotics may fail to prevent GBS sepsis in a number of infants born to mothers colonized with GBS or to those with acute chorioamnionitis.

Ampicillin↗