PubMed Health⌕ Search

Biomedical subjects

M Hiatt

Publications and source records attributed to M Hiatt.

35 records · Page 2Linked to original sources
PubMed1994

Blood pressure ranges in premature infants. I. The first hours of life.

We studied blood pressure in the first hours of life in a cohort of 1105 preterm infants weighing 501 to 2000 gm; these infants represented 83% of all births at these weights that resulted in admission to three intensive care nurseries during a 34-month period between 1984 and 1987. To assess the effects of specific risk factors, we identified 244 healthy infants, 164 infants who received mechanical ventilation but had no other conditions, 47 infants whose only risk factor was the presence of hypertension or preeclampsia in the mother, and 86 infants with depressed Apgar scores regardless of the presence of the other conditions. We documented each infant's minimum and maximum systolic (Smin, Smax) and diastolic (Dmin, Dmax) pressures during the first 3 to 6 hours of life. In the healthy group, Smin was 47 mmHg; Smax, 59 mmHg; Dmin, 24 mmHg; and Dmax, 35 mmHg. In the ventilation group, Smin was 41 mmHg; Smax, 57 mmHg; Dmin, 22 mmHg; and Dmax, 35 mmHg. The Smin and Dmin values were both significantly lower in infants who received mechanical ventilation than in healthy infants (p < 0.01). In the maternal hypertension group, Smin was 49 mmHg; Smax, 59 mmHg; Dmin, 25 mmHg; and Dmax, 34 mmHg. Only the Smin value was significantly higher than in healthy infants. In the group with low Apgar scores, Smin was 33 mmHg; Smax, 51 mmHg; Dmin, 19 Hg; and Dmax, 34 mmHg. Thus all these values were significantly lower than in all the other groups (p < 0.05). Of infants with low Apgar scores, 20% to 50% had values below the 5th percentile for healthy infants. Birth weight and gestational age correlated with blood pressure limits only in the infants with low Apgar scores. We conclude that in healthy premature infants the limits of systolic and diastolic blood pressure are independent of birth weight and gestational age. Infants with low Apgar scores tend to have lower pressures, and infants whose mothers have hypertension have higher pressures than infants in the healthy cohort.

Apgar Score↗
PubMed1993

The ventilatory response to carbon dioxide in high risk infants.

PURPOSE: To examine the ventilatory response to inspired carbon dioxide in infants considered to be at risk for sudden infant death syndrome or apnea. DESIGN: Clinical data measurement. SETTING: Infant apnea evaluation program of a university division of neonatology. PATIENTS: Fifty nine infants were full term characterized by the following diagnoses; siblings of infants who had died from sudden infant death syndrome (SIDS) (n = 7), apparent life threatening event (ALTE) (n = 24), apnea/cyanosis in the newborn nursery (n = 21), and controls. Sixty-nine infants were preterm and consisted of patients suffering from idiopathic apnea (n = 61), and bronchopulmonary dysplasia (n = 8). MEASUREMENTS: The ventilatory response to carbon dioxide was measured with a computerized waveform analyzer. MAIN RESULTS: Among full term infants no significant differences in the ventilatory slope in response to CO2 was seen. The range of mean slope was 19.4 +/- 7.6 in siblings of SIDS and 36 +/- 17 in control infants. Greater number of sibling of SIDS had slopes less than 20 ml/kg/min/mmHg in comparison to control infants. Sibling of SIDS had less increase in minute ventilation and inspiratory flow in response to CO2 administration in comparison to control infants. Preterm infants had similar slopes with a mean of 33 ml/kg/min/mmHg in infants with idiopathic apnea and 28 ml/kg/min/mmHg in infants with bronchopulmonary dysplasia. CONCLUSIONS: The large intragroup variability in the ventilatory response to inspired CO2, confirming previously reported data, comprises the benefit of this test. Thus, ventilatory response to CO2 administration is not useful in unselected patients at risk of SIDS or apnea.

Apnea↗
PubMed1993

Digital subtraction angiography--a new approach to brain death determination in the newborn.

The diagnosis of brain death in the newborn infants is elusive and often difficult. The lack of cerebral blood flow has become an identified criterion for loss of cerebral function. The diagnosis can be obtained by the technique of digital subtraction angiography, which is presented in two case reports demonstrating the utility of this technique.

Angiography, Digital Subtraction↗
PubMed1993

Neurodevelopmental outcome of infants with apnea of infancy.

The neurodevelopmental outcome of premature infants with persistent apnea of prematurity (AOP) is reported. Sixty premature infants (birthweight [BW], 1469 +/- 533 gm; gestational age [GA , 31 +/- 3 weeks) with AOP were compared to 47 control infants (BW, 1586 +/- 581 gm; GA, 31 +/- 3 weeks) matched for gestational age and degree of neonatal illness. The infants were enrolled in a multidisciplinary follow-up program, and outcome data between 12 and 24 months are reported. Assessments included the Bayley Scores of Infant Development, neurologic examinations, speech and hearing examinations. There were no significant differences in the cognitive outcome between the premature infants with AOP and the premature control group. In 50 of 60 infants the Bayley Mental Developmental Index was in the normal range (112 +/- 18) as was 39 of 47 of the control group (112 +/- 13). Delays in motor development were seen in both premature groups, although a greater percentage of premature infants with persistent apnea had mild motor delays than did control infants. There was a comparable incidence of cerebral palsy (8% vs 11%), speech delays (20% vs 23%), retinopathy (8% vs 13%), and esotropia (7% vs 4%) between the infants with AOP and the premature control infants. The presence of persistent neonatal apnea without additional adverse perinatal events did not appear to be associated with a higher incidence of significant developmental problems.

Apnea↗
PubMed1993

Cerebral blood flow measurements in the newborn dog.

Current methods of cerebral blood flow (CBF) determination provide only discrete, episodic data and are limited in assessing dynamic changes in cerebral circulation. We adapted a venous outflow technique employing cannulation of the superior sagittal sinus in newborn puppies to measure changes in CBF rapidly and sequentially during ventilatory maneuvers. CBF velocity (CBFV) was measured simultaneously with Doppler ultrasound of the anterior cerebral artery. Relationships between flow and velocity were determined during hypocarbia, hypercarbia, hypoxia and asphyxia. During hyperventilation, CBF decreased by a mean of 14%, and CBFV by 13%, whereas maximal CO2 inhalation increased CBF by 59% and CBFV by 110%. Although CBFV exhibited the same directional changes as shown by the area under the velocity curve, the magnitude of change was not proportional to flow. CBFV indicated trends in the direction of changes in flow in individual animals, but did not correlate with flow between animals. A fluctuating unstable pattern of CBFV, previously associated with neonatal intracranial hemorrhage, was demonstrated with hyperventilation and hypocarbia. During asphyxia, CBFV ceased 2-5 min prior to CBF, presumably reflecting continued brain perfusion from vessels other than anterior cerebral artery.

Animals↗
PubMed1993

Maternal grief after sudden infant death syndrome.

Six months after the death of their infants of Sudden Infant Death Syndrome (SIDS), the subjective impression of mothers anonymously rating their initial and present grief was that there had been a reduction in all symptoms (p < .001). However, an increase in the relative ranking of some cognitive symptoms over somatic ones, the association of certain lifestyles and situational variables with higher levels of grief, and the implication for future symptoms of family decisions made during bereavement underscore the importance of continuing active support for these families. In relative ranking, guilt rose from 10th to 5th most prominent symptom, particularly among the 34% of mothers whose infants manifested clinical symptoms (p < .05). Single mothers had higher grief scores both initially (p < .05) and at 6 months (p < .002), were almost three times more likely to become pregnant within 6 months of the death but only one-third as likely to attend a support group, and were also more likely to move after the death (44% vs 25%). Mothers whose infants had been discovered by another caregiver reached out more to a crisis intervention service of a support program available to SIDS families (p < .05). Mothers without surviving children had grief levels comparable with those with children but were less likely to rate their pediatrician's support as satisfactory, increasing the probability that they would change physicians with subsequent children, thereby losing continuity of care and support.

Adult↗
PubMed1987

Esophageal perforation in the neonate: an emerging problem in the newborn nursery.

We report 11 cases of esophageal perforation in the neonate, in whom no surgery was performed for repair of the perforation, nor was any cervical or mediastinal drainage carried out. The perforation was in the cervical esophagus in all cases where an esophagram was performed. Nine were in premature babies (580 to 1,350 g), and two were full-term babies. There were two deaths in small prematures (580 and 935 g), from extreme prematurity and intraventricular hemorrhage, with no morbidity or mortality related to the esophageal perforation. The babies presented as esophageal atresia, or pneumothorax with the feeding tube in the right chest, or an abnormal right upper extrapleural air collection with infiltrate. Barium esophagram showed a classic "double esophagus" configuration. Two babies were mistakenly operated on, one with a diagnosis of esophageal duplication, and one had a gastrostomy for a diagnosis of esophageal atresia. Esophageal perforation in the neonate is an iatrogenic disease that may mimic esophageal atresia, and may be managed without surgical intervention.

Diagnosis, Differential↗
PubMed1986

Effect of caffeine on pneumogram and apnoea of infancy.

We studied the efficacy of caffeine in improving pneumogram abnormalities and relieving clinically important apnoea of infancy in 23 infants. After obtaining a 12 hour pneumogram we administered caffeine citrate in a loading dose of 20 mg/kg followed by 5 mg/kg once daily. This dose achieved a trough caffeine blood concentration of 9.6 (SD 2.0) micrograms/ml. A repeat pneumogram performed seven to 10 days after the first pneumogram showed a significant reduction in the number of short and prolonged attacks of apnoea as well as in the per cent periodic breathing and apnoea density. Episodes of prolonged apnoea disappeared in all infants after administration of caffeine and in 11 infants all pneumogram abnormalities resolved. This improvement in the results of pneumograms was associated with resolution of clinically important apnoea requiring intervention. Caffeine was administered for 3.4 (SD 1.3) months and was well tolerated by all except two infants. We conclude that treatment with caffeine is helpful in preventing attacks of apnoea that require intervention, and improvement in the results of pneumograms after administration of caffeine predicts this favourable response.

Apnea↗
PubMedDate not supplied

Neonatal thrombosis with anticardiolipin antibody in baby and mother.

The anticardiolipin antibody is associated with increased risk of thrombosis, which is manifested with various clinical presentations, including vascular thrombosis, recurrent fetal wastage, and neurologic defects. We report a case of neonatal thrombosis occurring in the renal vein and inferior vena cava associated with moderate positive anticardiolipin antibody titer in the baby while the maternal serum showed even stronger anticardiolipin antibody of immunoglobulin G class. Subsequent follow-up over the 4 months postpartum period showed a disappearance of the antibody in the baby, whereas the mother's antibody persisted. This case illustrates the fact that the maternal anticardiolipin antibody can be transferred to the fetus and may be a risk factor for thrombosis in the neonates. Anticardiolipin antibody syndrome should be considered in the differential diagnosis of neonatal thrombosis.

Adult↗
PubMedDate not supplied

Nurses' assessments and management of pain in children having orthopedic surgery.

The specific aims of this research project were to (a) describe selected verbal, nonverbal, and physiological arousal indicators of the child's pain; (b) describe which pain indicators were most influential to nurses in decision-making about interventions for managing the child's pain; (c) describe pain interventions used by nurses; (d) compare postoperative analgesic orders to recommended dosages for the children; and (e) explore relationships between the child's self-report of pain and medication dosages administered. Subjects included 19 children aged 5-17 years who experienced 20 orthopedic surgical procedures (one child had two surgeries one week apart). Data were collected by staff nurses for the first five days after surgery. Pain levels were reported using the Oucher Scale. Postoperative pain was reported at moderate levels and showed only a gradual decrease throughout the hospital stay. Nonverbal pain indicators included crying and tense face. The child's complaint of pain and reported Oucher scores were most influential in influencing nurses to intervene in the child's pain. Nonpharmacological comfort measures included positioning and reassurance. All children received medications for pain; 49% of the orders were within the recommended therapeutic dosage range. A small but significant correlation was found between the child's reported pain level and the morphine equivalents of pain medication received. Recommendations included development of nursing flow charts that provide space to record pain levels and nursing interventions, in-service education for nurses on nonpharmacological interventions, and further research with a larger sample and a single pain rating scale.

Adolescent↗
PubMedDate not supplied

The protective role of bilirubin in oxygen-radical diseases of the preterm infant.

We hypothesized that because bilirubin is a potent free-radical quencher, infants without disorders that have oxygen-radical disease (ORD)-mediated mechanisms may have higher bilirubin levels than infants suffering from conditions possibly associated with ORD-mediated mechanisms (e.g., necrotizing enterocolitis, broncopulmonary dysplasia, intraventricular hemorrhage, and retinopathy of prematurity). We identified 25 infants (birth weight 912 +/- 208 gm, gestational age 27 +/- 3 weeks) who comprised the ORD group and compared them with 57 controls (birth weight 1242 +/- 248 gm, gestational age 31 +/- 3 weeks). Infants with ORD had lower peak serum bilirubin concentrations, later ages at peak, and lower incidence of peak bilirubin concentrations exceeding 10 or 15 mg/dl. In addition, these infants exhibited a slower rate of bilirubin rise and a smaller area under the bilirubin-time curve measure compared with controls. To control for different birth weights, we analyzed subgroups weighing < 1000 gm. Significant differences were again identified in peak bilirubin concentrations, age at peak, phototherapy duration, and area under the curve. In this population of preterm infants, higher bilirubin levels were associated with a lower incidence of oxygen radical-mediated injury.

Bilirubin↗