Increased cerebral blood flow velocity in infants of mothers who abuse cocaine.

The pharmacologic effects of cocaine are considered to be secondary to an enhancement of the effects of circulating catecholamines. The effect of intrauterine cocaine exposure on the cerebral blood flow velocity was studied in 20 full-term newborn infants whose urine screens were positive for cocaine and in 18 nonexposed healthy full-term newborn infants whose urine screens were negative for cocaine metabolites. On the first day of life, peak systolic, end diastolic, and mean flow velocities in the pericallosal, internal carotid, and basilar arteries and mean arterial blood pressures were significantly greater in infants who had been exposed to cocaine. On day 2, cerebral blood flow velocities and mean arterial blood pressures were similar in exposed and nonexposed infants. The increase in mean arterial blood pressure and in cerebral blood flow velocity on the first day of life indicates a hemodynamic effect of cocaine that may put the infant exposed to cocaine at a greater risk of intracranial hemorrhage.

Thyroid indices in arterial and venous cord blood: significantly greater levels of reverse triidothyronine in venous blood than in arterial blood.

Paired arterial and venous cord blood samples were obtained from 42 normal newborns (24 males and 18 females). T4 was determined in all paired samples. In addition, other indices were determined: T3 in 40, RT3 in 29, TBG in 29, thyroglobulin (Tg) in 14, and TSH in 11. Gender difference in any of the thyroid indices was not found. Arterial and venous cord serum thyroid indices correlated positively (T4, r = 0.743; T3, r = .907, rT3, r = .920; TBG, r = .752; Tg, r = .934, and TSH, r = .989; P less than 0.005). The difference between the means +/- SD of arterial and venous levels was significant (P less than 0.01) only for rT3 (191 +/- 43.2 v 224 +/- 55.8 ng/dL). Arterial (T4 v T3, r = .453, P less than .005; T4 v RT3, r = .660, P less than 0.005) and venous (T4 v T3, r = .620, P less than 0.005; T4 v rT3, r = .612, P less than 0.005); T3 and rT3 levels correlated positively with T4 levels. In contrast, T3 and rT3 levels for arterial (r = .216, P greater than 0.1) and venous (r = .216, P greater than 0.1) samples did not show a significant correlation. These data are in keeping with earlier reports for animal placental models studied in vitro, suggesting that placental inner ring deiodination of maternal thyroxine is a source of fetal RT3.

Care of very low birth weight infants by neonatal nurse clinicians.

In 1980, the medical facility at the authors' hospital developed a program to train neonatal critical care nurses for primary care provider roles in the intensive care nursery. The neonatal nurse clinician (NNC) program consists of a didactic portion that emphasizes physiology and pathophysiology of sick newborns, and an internship that focuses on the medical needs of very low birth weight (VLBW) neonates. At the completion of the internship, the NNC is assigned to be the primary care provider for infants with birth weights less than or equal to 1,250 g. This report discusses the NNC training program and the five-year experience with the NNC caring for VLBW infants.

Factors differentiating postponed neonatal death from survival in low birth weight infants.

Although survival of low birth weight infants during the neonatal period has improved, an increasing percentage of infants succumb after 28 days but before discharge from the nursery. In a retrospective study we compared 11 postponed neonatal deaths (PND) with survivors matched for birth weight, gestational age, gender, race, inborn or outborn status, and year of birth in an attempt to identify possible differentiating factors early in the clinical course. Evaluation of antenatal, intrauterine, and early nursery events could not differentiate the two groups. By day 14, however, significantly more PND required assisted ventilation because of poor respiratory effort and total parenteral nutrition because of poor gastrointestinal motility. Metabolic differences were noted at this time in the serum bilirubin, phosphorus, and chloride levels. At autopsy all infants had evidence of CNS injury, and moderate chronic lung disease, and in addition nine infants had bronchopneumonia. The major differences between the PNDs and survivors may primarily involve neurologic control of respiration and gastrointestinal motility. Early recognition of PND may have important medical, ethical, and financial implications for newborn intensive care.

Multidetector computed tomography of acute vascular injury in blunt abdominal/pelvic trauma: imaging predictors of treatment.

PURPOSE: The purpose of this study was to analyze the multidetector computed tomography (MDCT) morphologic characteristics of non-aortic acute vascular injuries (AVI) in patients with blunt abdominopelvic trauma that predict treatment. METHODS: CT scans of 65 trauma patients with non-aortic AVI were reviewed. AVI morphology was categorized as linear or round. The organ of involvement, location of hemorrhage, initial size of hematoma, and hemodynamic status were recorded. Expansion rates of the hematoma were calculated in 40 patients who had delayed imaging. Multivariate regression was used to analyze the morphologic features of AVI and treatment. RESULTS: Patients with linear AVI were four times more likely to require aggressive treatment (surgery or embolization) than those with a round morphology, independent of the hemodynamic status. There was no main effect of the organ involved, location of hemorrhage, initial bleed size, or expansion rate on the probability of aggressive treatment. CONCLUSION: The location, initial size, and expansion rate of AVI are not significant predictors of aggressive treatment with surgery or embolization. Linear morphology of AVI, however, is more likely to require aggressive treatment than round AVI, independent of the hemodynamic status. Linear AVI likely reflects a spurting jet of active extravasation, whereas round AVI likely represents a pseudoaneurysm or slow bleed.

Are small for gestational age infants at higher risk for intracranial lesions?

The association of small for gestational age (SGA) and central nervous system (CNS) abnormalities is controversial. Some reports suggest that SGA infants are at higher risk, whereas other data indicate that growth retardation may have a protective effect on the CNS. We compared the cranial ultrasound results of 197 SGA infants with 197 appropriate for gestational age (AGA) neonates, matched for gestation and gender, to determine if growth retardation is associated with a difference in ultrasound detectable CNS abnormalities. Infants with external dysmorphology or toxoplasmosis, rubella, cytomegalovirus, herpes simplex (TORCH) infections were excluded. We found 51 (26%) intracranial abnormalities in the SGA infants compared with 41 (21%) in the AGA controls (difference not significant). The most common lesions were hemorrhagic or ischemic, and the incidence was similar for both groups, 43 (22%) for SGA and 35 (18%) for AGA infants. The type and severity of hemorrhagic or ischemic lesions was also the same. Ventriculomegaly, not associated with hemorrhage, and structural lesions were also comparable, nine (5%) in the SGA and six (3%) in the AGA infants. We conclude that SGA infants without external dysmorphology or TORCH infections are not at increased risk for CNS abnormalities detectable by cranial ultrasound.

Cardiovascular effects of caffeine therapy in preterm infants.

Theophylline therapy increases left ventricular output in preterm infants by a combination of positive inotropic and chronotropic effects. The cardiovascular effects of caffeine were evaluated in 20 clinically stable preterm infants. Ten infants received intravenous caffeine citrate with a loading dose of 20 mg/kg and a maintenance dose of 5 mg/kg every 24 hours, and 10 infants were control subjects. Left ventricular output, stroke volume, and heart rate were measured by using a combination of two-dimensional and pulsed Doppler echocardiography and mean arterial blood pressure by oscillometry (Dinamap, Critikon, Division of McNeil Laboratories, Irvine, Calif) before the start and on days 1, 2, 3, and 7 of caffeine therapy and 7 days after discontinuation of therapy. Compared with controls, left ventricular output and stroke volume were significantly increased on days 1 to 7 of caffeine therapy. Caffeine led to an increase in the mean arterial blood pressure on the first 3 days of therapy, but the heart rate did not change. These data indicated that caffeine administration leads to a significant increase in left ventricular output in preterm infants and that this inotropic effect is accompanied by a pressor effect.

Postponed neonatal death in the premature infant.

Improved obstetrical and neonatal care has increased survival for many small premature infants. However, there remains a distinct group who die of complications later in infancy. The autopsy findings associated with these "postponed neonatal deaths" were the subject of our retrospective study of 18 premature infants (mean estimated gestational age, 28.6 +/- 0.6 weeks) who survived from 4 weeks to 4 months of age (mean, 70 +/- 11 days). All 18 infants required prolonged artificial ventilatory support and parenteral nutrition. The major findings at autopsy were similar in all cases and included bronchopulmonary dysplasia, hepatic cholestasis and fibrosis, abnormalities of endochondral ossification, and diffuse cerebral gliosis and infarction. Infection was the most common cause of death, and most of the infants died with acute bronchopneumonia. These postponed neonatal deaths, while they do not appear in standard neonatal mortality statistics, represent a problem of concern.

Prophylactic oral nystatin and fungal infections in very-low-birthweight infants.

Prevention of systemic fungal infection in the very-low-birthweight infant is important since it is associated with a high morbidity and mortality. To determine if oral nystatin administration could prevent fungal colonization and infection, we evaluated 67 preterm infants with birthweights less than 1250 gm. Thirty-three infants received 1 ml (100,000 units/ml) of nystatin inside the mouth every 8 hours until 1 week after extubation. Oropharyngeal, rectal, blood, and urine cultures were obtained on the 1st day of life and weekly. Endotracheal cultures were obtained three times a week from intubated infants. Four (12%) of the 33 nystatin-treated infants had positive cultures, two (6%) developed systemic infection. The control group consisted of 34 infants, 15 (44%) had positive fungal cultures and 11 (32%) developed systemic infection. Fungi isolated were Candida species and Torulopsis glabrata. Colonized infants were dependent on the respirator (P less than 0.001), had indwelling catheters (P less than 0.01), and received antibiotics (P less than 0.05) for a longer period than infants free from fungi and their mortality was significantly higher (P less than 0.05). We conclude that prophylactic administration of oral nystatin reduces fungal colonization and infection in very-low-birthweight infants.

Brain injury and intrauterine death.

Many of the stresses contributing to brain injury in the intrapartum or neonatal period may also exist prenatally. To define this problem, we reviewed the clinical features and neuropathologic findings in 433 consecutive stillbirth autopsies. Twenty-five had evidence of periventricular/intraventricular hemorrhage or gliosis. Twenty infants had died in utero before active labor and five during delivery. Nine stillbirths were infected. Ten cases had periventricular/intraventricular hemorrhage alone, five had the hemorrhage with parenchymal hemorrhage, five had parenchymal hemorrhage only, and five had gliosis. This group of 25 cases establishes that intrauterine brain injury is not rare. Separation of antepartum events occurring in utero from those imposed during labor, delivery, resuscitation, and the neonatal period is very important and has significant medical and legal implications.

Acceleration time in cerebral arteries of preterm and term infants.

We measured the acceleration times in the pericallosal, internal carotid, and basilar arteries with two-dimensional/pulsed Doppler ultrasonography in 145 nondistressed preterm and term infants between 24 and 48 hours after birth. In all three arteries we found a linear relationship between the acceleration time and menstrual age or birth weight. These findings were determined by changes in peak systolic flow velocity, but not by changes in mean arterial blood pressure or cardiac output. We speculate on an important role for cerebral autoregulation in the acceleration time variations between newborn infants of differing menstrual ages and birth weights.

Indications for routine cranial ultrasound scanning in the nursery.

Cranial ultrasonography provides important diagnostic information in neonates. The clinical indications for routine scanning in newborn infants, however, are not established. The purpose of this study is to determine the incidence of cranial pathology detectable by ultrasound in certain clinical states in the neonate. We reviewed the scans and clinical states of 1,031 neonates born between April 1981 and February 1985. We found term infants with dysmorphic features to have the highest incidence of neuropathology (46%), followed by term infants born with macrocephaly (33%), preterm infants (26%), term infants with seizures (26%), and term infants with 1- and 5-min Apgar scores less than 7 (13%). We found a lower incidence (less than 5%) of abnormal CNS findings in the nonasphyxiated term infants with split sutures, cephalohematoma, abnormal neurologic examination, and idiopathic jitteriness. Based on our findings we have concluded that it is important to scan routinely all premature infants, term infants with dysmorphic features, macrocephaly, or seizure disorder, and infants with 1- and 5-min Apgar scores less than 7; routine scanning of term infants with split sutures, cephalohematoma, abnormal neurological examination, or idiopathic jitteriness is not indicated.

Limitations of theophylline in the treatment of apnea of prematurity.

Theophylline is commonly used to treat apnea of prematurity. To determine the effectiveness of theophylline with respect to gestational and postnatal age, we conducted a controlled study in 43 premature infants with idiopathic apnea. Three of the 21 treated and eight of the 22 control infants developed respiratory failure. Eight of the 11 infants with respiratory failure had gestational ages of less than 31 weeks and had more than four apneic episodes during the first day of life. In the treated infants without respiratory failure, the number of apneic episodes by 24-hour intervals declined six days earlier than in the control infants. Apnea disappeared, however, at a similar time in both groups. Three treated infants and three control infants had apneic episodes persisting beyond the neonatal period. Patients treated with theophylline did not develop respiratory failure as often as control infants did. However, despite a reduction of apneic episodes, theophylline did not shorten the course of apnea of prematurity.

Cardiac output changes secondary to theophylline therapy in preterm infants.

The cardiovascular effects of theophylline were studied in 11 clinically stable preterm infants. Theophylline was given as aminophylline using a loading dose of 6.8 mg/kg and a maintenance dose of 2 mg/kg every 8 hours intravenously. Cardiac output, stroke volume, and heart rate were measured using a combination of pulsed Doppler ultrasound and M-mode echocardiography. Compared with day 0, an increase was found in both cardiac output (P less than 0.01) and stroke volume (P less than 0.02) on days 1, 2, and 3. By day 7, stroke volume was comparable to pretreatment values, whereas cardiac output was still increased. Heart rate was augmented significantly (P less than 0.01) throughout the treatment period. Mean arterial blood pressure did not change. All but one of the neonates had serum theophylline concentrations between 6 and 13 mg/L. We conclude that both inotropic and chronotropic effects are evident during the first days of theophylline therapy. The metabolic cost of the increased cardiac output in the preterm infant with theophylline therapy deserves further attention.

Comparative evaluation of caffeine and theophylline for weaning premature infants from the ventilator.

Expedient weaning of infants from the respirator minimizes the risk of complications associated with assisted ventilation. Since theophylline and caffeine decrease apnea and enhance respiratory effort, we conducted a blinded, randomized comparative evaluation of each drug to determine extubation time and incidence of reintubation. Forty-five clinically stable premature infants receiving mechanical ventilation on minimal settings randomly were assigned to receive either theophylline (n = 23) or caffeine (n = 22) at least 1 day before and 5 days after extubation. From study entry to extubation, the mean number of days was 2.7 for both theophylline- and caffeine-treated infants. Three theophylline- and three caffeine-treated infants developed respiratory failure necessitating reintubation (NS). These findings indicate that for premature infants on minimal respiratory settings, the duration of intubation and the incidence of reintubation after treatment with theophylline or caffeine were similar.

Effect of antepartum glucocorticoid administration upon neonatal respiratory distress syndrome and perinatal infection.

A double-blind, randomized study comparing the antepartum use of betamethasone (12 mg), methylprednisolone (125 mg), and hydrocortisone (250 mg) was performed to evaluate effect on neonatal respiratory distress syndrome and perinatal infection. Of 144 mothers and 149 infants entered, 92 mothers and 97 infants were available for analysis. The betamethasone-treated group had a significantly reduced incidence of severe respiratory distress syndrome (4%) compared with the control group (26%; p = 0.038); this effect was confined to patients who received at least two doses. No similar effect was found in the methylprednisolone or hydrocortisone groups. Neonatal infection and neonatal mortality rate were not affected by glucocorticoid use. Maternal infection was significantly increased in hydrocortisone-treated patients who were delivered vaginally compared with control patients (all patients: 50% versus 9.5%, p less than 0.05; with ruptured membranes: 63% versus 15%, p = 0.04). No similar increase in maternal infection was found with betamethasone or methylprednisolone use.