PubMed Health⌕ Search

Biomedical subjects

R J Ellingson

Publications and source records attributed to R J Ellingson.

At least 37 records · Page 2Linked to original sources
PubMed1982

Respiratory pauses and apnea during daytime sleep in normal infants during the first year of life: longitudinal observations.

Respiratory pauses (3-10 sec in duration), apnea (less than 10 sex in duration), and periodic respiration observed in thoracic respirograms were measured in 226 polysomnograms obtained on 17 normal infants during the first year of life. All subjects had one or more respiratory pauses in a majority of recordings; 35% had respiratory pauses in all recordings; 75% of respiratory pauses were associated with body movement. There is marked intersubject and even intrasubject variability in respiratory pause rates. The range of mean respiratory pause rates among subjects was 2.0 - 14.4/h, and for single recordings was 0.0 - 43.6/h. Their occurrence was directly related to the occurrence of periodic respiration. Rates were higher during REM and indeterminate sleep than during slow wave sleep. There was no significant trend toward increase or decrease in respiratory pause rate during the first year post term. Apnea occurred in only one of the 226 recordings (0.4%). Periodic respiration occurred in 8 of 17 subjects (47%), and in 25 of 226 recordings (11%). Its occurrence was unrelated to sleep stage. The following conclusions are considered valid on the basis of the data presented and reports in the literature: (1) Rates of respiratory interruption are higher before than after 40 weeks conceptional age. (2) There is considerable intersubject variability in rates of respiratory interruptions. (3) Respiratory pauses are common during sleep in normal human infants. (4) Respiratory pauses occur more frequently with movements than in their absence. (5) Respiratory pause rates are higher during REM sleep than during slow wave sleep. (6) Apneas of greater than 10-15 sec duration do occur in normal infants, but are rare. From the clinical viewpoint, respiratory pauses (less than 15 sec) of the central type, regardless of abundance, and periodic respiration cannot by themselves be used as evidence that a baby is at risk of anything. The occurrence of apneas (greater than 15 sec duration), especially if any are of the obstructive or mixed types (and perhaps respiratory pauses of the obstructive and mixed types), and/or if associated with bradycardia or decrease in oxygen saturation, indicate sleep apnea syndrome and suggest risk of sudden infant death.

Circadian Rhythm↗
PubMed1982

Development of sleep spindle bursts during the first year of life.

Sleep spindles, as defined in the international electroencephalography (EEG) glossary, are distinguished from spindle bursts seen in the EEGs of premature infants. Classical sleep spindles do not occur in prematures. They first appear clearly in the EEG during slow wave sleep from the 4th week postterm (44 weeks conceptional age) and are normally present in all infants' EEGs by 9 weeks postterm. During the first year of life they may be of high voltage relative to their appearance in older children and adults and are commonly characterized by variable degrees of interhemispheric asymmetry and asynchrony. Individual differences are great. Some features of clinical significance are discussed.

Cerebral Cortex↗
PubMed1981

Interhemispheric amplitude symmetry in the EEGs of normal full term, low risk premature, and trisomy-21 infants.

RMS measurements of amplitude symmetry were calculated for samples of typical active and quiet sleep periods in 12 normal full term, 5 premature and 7 Trisomy-21 infants from recordings obtained at 1, 4, 12 26 and 52 weeks post term. The frequency distributions of the symmetry data for each group did not deviate significantly from the expected normal distributions. The mean symmetry ratios were not significantly different among the 3 groups. It was concluded that the EEGs of the 3 groups are characterized by amplitude symmetry in the first year of life. The possibility that symmetry data may be used for classification of abnormal EEGs was discussed.

Down Syndrome↗
PubMed1980

Development of EEG and daytime sleep patterns in low risk premature infants during the first year of life: longitudinal observations.

Long daytime EEG-polygraph recordings were obtained at 36, 38, and 40 weeks conceptional age, weekly thereafter for 12 weeks, and at 26 and 52 weeks post term in 5 infants born at 30--33 weeks gestation. The babies have developed normally for 18--38 months. All 74 EEGs were normal for age. Derived data were compared with similar data from 17 normal full-term infants. The tracé alternant pattern disappeared earlier in the premature than in the control group (mean ages 21.4 vs. 33.4 days post appeared earlier in the premature group (mean ages 35.4 vs. 43.8 days; P < 0.05). There were no age differences between the groups with respect to (1) the shift from active sleep onset to quiet sleep onset, (2) active sleep and quiet sleep as percentages of total sleep time, or (3) disappearance of frontal sharp waves. Overall attainment of "infantile" EEG sleep patterns occurred at 35--60 days post term (mean 43.8) for the permature group and at 27--66 days (mean 46.4) for the full-term group (difference not significant). These findings indicate that no significant errors will be made in clinical practice by applying the same maturational criteria to the post-term EEGs of prematures as to the EEGs of full-term infants.

Age Factors↗
PubMed1980

Development of EEG and daytime sleep patterns in normal full-term infant during the first 3 months of life: longitudinal observations.

EEG polygraph recordings of 1 to over 4 h duration were obtained during daytime sleeps weekly from birth to 11-13 weeks of age in 17 normal full-term newborns. Analysis of the recordings permitted more precise specification of the time courses of early developmental changes in EEG patterns related to the sleep cycle. The tracé alternant pattern of quiet sleep was seen up to 2 weeks post term in all subjects, but in none beyond 6 weeks. Active sleep onset occurred in 80% of daytime sleeps at 1-3 weeks and decreased rapidly over the next 5 weeks, but at 8-13 weeks was still seen in 5-10% of the recordings. Rolandic sleep spindle bursts appeared in some subjects as early as 4 weeks post term and were present in all beyond 8 weeks. Based upon these 3 criterion variables, the transition from 'perinatal' to 'infantile' EEG sleep patterns started at a mean age of 30.3 days and was completed at a mean age of 46.6.days. The earliest and latest completions of the transition were at 27 and 66 days, respectively. On the average the transition took just over 2 weeks. Frontal sleep transients were seen until 3 weeks post term in all subjects, but in none beyond 7 weeks. Active sleep decreased from just over 50% of total sleep time at birth to about 20% beyond 8 weeks. Percent-time quiet sleep increased proportionately. Indeterminate sleep remained relatively constant at 5-10 percent-time. A tendency for percent-time indeterminate sleep to be elevated in the presences of minor illnesses was observed. The usefulness of these, and other, EEG data in defining mature and immature EEGs in the neonatal period and the clinical significance of EEG immaturity are discussed.

Age Factors↗
PubMed1978

Interhemispheric synchrony in the EEGs of full-term newborns.

Cross correlations between 4 homologous pairs of ear-reference derivations were calculated for 45-sec digitized samples of typical active and quiet sleep in 19 selected normal newborns at 21--70 h after term birth. Repeat recordings were obtained in 9 subjects 24 h after the original recordings and another set of cross correlations was calculated. For comparison, similar recordings were obtained from 4 asymptomatic young adults and cross correlations were calculated for 45-sec samples of typical stage 4 and stage REM sleep and for stage W both before and after sleep. Mean cross-correlation coefficients at zero time lag were generally higher for the adult sleep data than for the newborn data, but the differences were smaller than had been anticipated. The coefficients for active sleep data in the newborns were higher than for quiet sleep data, while in the adults the coefficients were higher for stage 4 than for stage REM. Coefficients were higher for convexity derivations than for temporal derivations in both newborns and adults. A review of the small available literature suggests that recording and analysis techniques may be significant variables determining the results obtained in such studies. The cross-correlation method of measuring interhemispheric synchrony may prove useful in identifying brain disorders in the postnatal period.

Age Factors↗