Cervical auscultation of suckle feeding in newborn infants

The authors recorded the sound signals during suckle feeding of six normal infants within the first two postnatal days. The sounds were recorded onto a cassette tape-recorder from a small microphone attached to the infant's neck, then displayed on an oscilloscope and analysed by digital signal processing techniques. These displays demonstrated acoustic patterns and temporal relationships which are not otherwise audible. The method and findings are described in detail, and the method should be useful in the clinical investigation of feeding and swallowing problems associated with more subtle neurological impairment and preterm birth.     

Deglutition apnoea as indicator of maturation of suckle feeding in bottle-fed preterm infants

The maturation of deglutition apnoea time was investigated in 42 bottle-fed preterm infants, 28 to 37 weeks gestation, and in 29 normal term infants as a comparison group. Deglutition apnoea times reduced as infants matured, as did the number and length of episodes of multiple-swallow deglutition apnoea. The maturation appears related to developmental age (gestation) rather than feeding experience (postnatal age). Prolonged (>4 seconds) episodes of deglutition apnoea remained significantly more frequent in preterm infants reaching term postconceptual age compared to term infants. However, multiple-swallow deglutition apnoeas also occurred in the term comparison group, showing that maturation of this aspect is not complete at term gestation. The establishment of normal data for maturation should be valuable in assessing infants with feeding difficulties as well as for evaluation of neurological maturity and functioning of ventilatory control during feeding.     

The influence of feeding patterns on head circumference among Turkish infants during the first 6 months of life

The influence of various feeding patterns on physical growth and mental development of the infant, particularly during the first 6 months of life, is an important subject. Head circumference values of 172 healthy new-born infants were included in the study; 62 were exclusively breast-fed (BF), 58 were mixed-fed (MF) and 52 were formula-fed (FF). No significant differences were found in head circumference values between the groups at birth (BF 35.2 ± 0.1, MF 35.1 ± 0.1, FF 35.0 ± 0.1 cm for boys and BF 35.0 ± 0.1, MF 34.9 ± 0.1, FF 34.8 ± 0.1 cm for girls). At the end of the first month, the infants in the BF group (38.3 ± 0.1 cm and 37.9 + 0.1 cm for boys and girls, respectively) had strikingly greater head circumference measurements than the others (MF 36.7 ± 0.1, FF 36.6 ± 0.1 cm for boys and MF 36.5 ± 0.1, FF 36.4 ± 0.1 cm for girls) (P < 0.05). However, in the subsequent 4-month period, the values detected in each group were almost the same. At the sixth month, head circumference-for-age values of infants in MF (42.6 ± 0.1 cm for boys, 41.4 ± 0.1 cm for girls) and FF (42.5 ± 0.1 cm for boys, 41.5 ± 0.1 cm for girls) were well below those of BF group (43.7 ± 0.1 cm and 42.9 ± 0.1 cm for boys and girls, respectively) and the standard curve (P < 0.05). These results suggest that exclusive breast feeding is sufficient during the first 6 months, the most important period of life.     

Modulations in breathing patterns during intermittent feeding in term infants and preterm infants with bronchopulmonary dysplasia

As infants with bronchopulmonary dysplasia (BPD) have difficulty maintaining adequate levels of oxygenation during rest, it was decided to investigate how the additional respiratory demands associated with nutritive feeding disrupt their breathing rates. The sucking and breathing patterns of six (three male, three female) preterm infants (between 23 and 29 weeks gestational age at birth), classified as having BPD were individually compared with the patterns observed in 12 (six male, six female) healthy term (control) infants (> or = 38 weeks gestational age at birth) with no known respiratory ailments. All infants were recruited from the neonatal unit at Simpson's Maternity Pavilion, Edinburgh, Scotland. In general, the breathing patterns recorded for the infants with BPD during the pause periods of intermittent feeding lacked the striking regularity observed in the term infants. It was found that the severity of the BPD affected breathing rates by significantly reducing the duration and the regularity of a breath (P<0.05) while sucking during the intermittent phase of feeding.     

Developmental patterns of rhythmic suck and swallow in preterm infants

Twenty healthy preterm infants (gestational age 26 to 33 weeks, postmenstrual age [PMA] 32.1 to 39.6 weeks, postnatal age [PNA] 2.0 to 11.6 weeks) were studied weekly from initiation of bottle feeding until discharge, with simultaneous digital recordings of pharyngeal and nipple (teat) pressure and nasal thermistor and thoracic strain gauge readings. The percentage of sucks aggregated into 'runs' (defined as > or = 3 sucks with < or = 2 seconds between suck peaks) increased over time and correlated significantly with PMA (r=0.601, p<0.001). The length of the sucking-runs also correlated significantly with PMA (r=0.613, p<0.001). The stability of sucking rhythm, defined as a function of the mean/SD of the suck interval, was also directly correlated with increasing PMA (r=0.503, p=0.002), as was increasing suck rate (r=0.379, p<0.03). None of these measures was correlated with PNA. Similarly, increasing PMA, but not PNA, correlated with a higher percentage of swallows in runs (r=0.364, p<0.03). Stability of swallow rhythm did not change significantly from 32 to 40 weeks' PMA. In low-risk preterm infants, increasing PMA is correlated with a faster and more stable sucking rhythm and with increasing organization into longer suck and swallow runs. Stable swallow rhythm appears to be established earlier than suck rhythm. The fact that PMA is a better predictor than PNA of these patterns lends support to the concept that these patterns are innate rather than learned behaviors. Quantitative assessment of the stability of suck and swallow rhythms in preterm infants may allow prediction of subsequent feeding dysfunction as well as more general underlying neurological impairment. Knowledge of the normal ontogeny of the rhythms of suck and swallow may also enable us to differentiate immature (but normal) feeding patterns in preterm infants from dysmature (abnormal) patterns, allowing more appropriate intervention measures.     

Behavior of full term infants small for gestational age in the first three months of life

The objective was to compare the behavior of full-term infants small-for-gestational age (SGA) with full-term appropriate-for-gestational age (AGA). The sample considered 20 infants in the 1st, 2nd and in the 3rd months of life. The Bayley Scales of Infant Development-II were used, with attention to items related to Behavior Rate Scale (BRS). It was found that SGA infants showed lower average values in the BRS in the 2nd month. The Motor Quality Factor displayed significantly lower average values in SGA group, in the items Gross-motor Movement Required by Tasks, Control of Movements and Hypertonicity. The Attention/Arousal Factor in the items Exploration of Objects/Surroundings and Orientation to Examiner displayed significantly lower average values in the SGA group.     

Ultrasound demonstration of tongue motions during suckle feeding

In this study the authors used ultrasound to demonstrate characteristic internal actions of the tongue during suckling. Its medial portion, into which the genioglossus is inserted, moves in relation to its lateral portions, into which the styloglossus and hyoglossus are inserted. A peristaltic wave of successive inferior and superior displacements moves posteriorly in the medial portion, compressing or 'milking' the nipple and propelling the expressed milk towards the pharynx. The lateral portions of the tongue enclose the nipple and the bolus and serve as reference for the displacements of the medial portion. These observations are related to anatomical studies of the tongue. The coordination pattern of suckle is compared with that of pharyngeal swallow. In instances where suckle and swallow are immediately sequential, the peristalsis which is common to both is continuous in the oral and pharyngeal portions of the food pathway.     

Neurodevelopment of full-term small-for-gestational age infants in the second month of life

The objective of the present study was to assess and to compare the neurodevelopment of full-term adequate (AGA) or small-for-gestational age (SGA) infants in the second month of life. Sixty-seven infants were evaluated: 43 AGA and 24 SGA, making use of the Bayley Scales of Infant Development. The SGA group Index Score (IS) was significantly lower in Mental and Motor Scales. Considering the body proportionality (Asymmetric, Symmetric-SGA and Control group) there was difference in Motor Scale (p=0.003) with lower scores in the Symmetric-SGA group. Comparing to the Control group IS percentiles, in Mental Scale there was difference between Asymmetric X Symmetric-SGA; in Motor Scale, there was difference between the Asymmetric X Control (p=0.039) and Symmetric-SGA X Control (p=0.007) groups; there was no difference between Asymmetric and Symmetric-SGA although both exhibited lower scores than the Control group.     

Respiratory patterns and strategies during feeding in preterm infants

Because patterns of integration of respiration into rhythmic suck-swallow efforts are highly variable, we examined the vagaries of respiratory efforts as they evolve from the first tentative attempts at integration through more complex rhythmic interactions, with a focus on several strategies in which breathing and suck-swallow are coordinated. Thirty-four preterm infants (18 males, 16 females) of 26 to 33 weeks gestational age, 32 to 40 weeks postmenstrual age (PMA), and 2 to 12 weeks postnatal age were studied weekly from initiation of bottle feeding (using breast milk or preterm formula, both fed from a bottle) until discharge, with simultaneous digital recordings of pharyngeal pressure, nasal thermistor airflow, and thoraco-abdominal strain-gauge readings. Exceptional patterns of feeding-adapted variations of respiration were noted, including breathing during swallow, alternating blocks of suck-swallow and respiration efforts, narial airflow without thoracic movement, modulation of respiratory phase relationship against swallow rhythm, and paired rhythms with swallow:breath ratios of more than 1:1. Some of these strategies were developmentally regulated. Alternating blocks of suck-swallow and respiratory efforts were only seen in the earliest (PMA 32-33 wks) studies. In contrast, coordination and phase relationships of suck-swallow and breathing stabilized over time, as did the percentage of synchronized narial and thoracic respiratory efforts, which increased significantly after 36 weeks PMA compared with synchronization at 32 to 33.9 and 34 to 35.9 weeks PMA (p<0.05). There was also a significant positive correlation between percentage synchronization and PMA (r=0.58; p<0.001). The strategies and patterns noted here further clarify the developmentally regulated coordination of suck, swallow, and respiration into mature infant feeding, and may be predictive of those infants with short- and long-term feeding or developmental difficulties.     

Spectral analysis of electroencephalogram during sleep-related apneas in pre-term and term born infants in the first weeks of life.

OBJECTIVES: A correlation between sudden infant death syndrome (SIDS) and apnea has been discussed in a variety of studies. We analyzed polysomnographic data in 51 infants and investigated correlations between the manifestation of apneas and changes in EEG pattern. METHODS: Measurements were performed by means of the commercial polysomnographic device 'ALICE III'. Spectral analysis of certain parts of the registered EEG was performed. RESULTS: During apnea a reduction of the EEG amplitude was seen. The extent of the decrease differed slightly between the frequency bands. CONCLUSIONS: According to the widespread agreement that a lower voltage of electrical brain activity is a fundamental sign of waking up, we hypothesize that the observed change might be an immature type of arousal reaction.     

Changes in gait patterns with rhythmic auditory stimulation in adults with cerebral palsy

The objective is to evaluate the changes in gait patterns with rhythmic auditory stimulation (RAS) in adults with cerebral palsy (CP). Fourteen CP with bilateral spasticity participated in this study. A repeated-measures analysis of gait was performed in the presence and absence of RAS. Thirty healthy controls were also recruited. Each subject walked 10 m at their comfortable walking speed. Temporospatial data and kinematic parameters of gait were analyzed without RAS and with RAS. RAS was provided using a combination of a metronome beat set to the individual's cadence and rhythmic cueing from a live keyboard playing. Kinematic parameters, gait deviation index (GDI) as a measure of overall gait pathology, and asymmetry of temporospatial data were assessed. Gait analysis revealed that anterior tilt of pelvis and hip flexion during a gait cycle was significantly changed with RAS (p < 0.05), whereas there were no statistical differences in knee, ankle, and foot kinematic parameters. Additionally, the GDI exhibited a modest, but a statistically significant, improvement with RAS (p < 0.05). Based on ambulatory status, household ambulators showed that side-to-side asymmetry of step length as well as the GDI was significantly attenuated with RAS (p < 0.05). Walking with RAS resulted in kinematic changes of the pelvic and hip movement in spastic CP. Especially, the application of RAS immediately ameliorated overall gait pathology as well as temporospatial asymmetry in household ambulators. Therefore, RAS may be one of the therapeutic tools for gait training in adults with CP.     

Changes in CSF neurotransmitters during the first year of life

Changes in cerebrospinal fluid neurotransmitter metabolites in 25 children younger than 1 year of age were analyzed to assess maturation of the central nervous system and were compared to cerebrospinal fluid from older children and adults. Significant inverse correlations (P < .05) with aging were observed for tryptophan, 5-hydroxytryptophan, 5-hydroxyindoleacetic acid, kynurenine, tyrosine, dopa, dopamine, dihydroxyphenylacetic acid, homovanillic acid, norepinephrine, and 3-methoxy-4-hydroxyphenylglycol concentrations. There were no significant differences observed with respect to age in the cerebrospinal fluid serotonin, 3-hydroxykynurenine, and 3-methoxytyramine concentrations. This study suggests that changes in the major cerebrospinal fluid neurotransmitters occur with increasing age during the neonatal period. Because these findings are preliminary, additional patients require study.     

Visual evoked potentials in preterm infants during the first hours of life

Flash evoked cortical potentials (VEPs) were studied in 33 preterm infants with gestational ages from 27 to 33 weeks. During the first 12 h after birth a visual response was evoked in all infants. Better estimates of the VEP latency and amplitude were obtained by using the values of 3 VEPs recorded at 30 sec intervals. The VEP latency decreased during the first hours of life, which was accounted for by an increase in core temperature; the latency decreased 6 msec/degrees C increase. Changes in amplitude were less influenced by changes in temperature. Both VEP latency and amplitude were inversely related to gestational age, but there was no association between head circumference and latency. The flash intensity could be reduced from 155 cd to 39 cd without any effect on VEP latency or amplitude. Similarly, a variation of background illumination below 200 lux did not cause VEP changes. The VEP was not affected by development of minor subependymal haemorrhages but it was severely attenuated during a short episode of hypoxia. It is suggested that when taking core temperature into account the VEP can be used to determine changes in the cerebral function in preterm infants.     

Plantar grasp reflex in high-risk infants during the first year of life

For most primitive reflexes, retention of the reflex beyond the period when it should no longer be elicited suggests a pathologic process within the central nervous system. However, for certain primitive reflexes, such as the plantar grasp reflex, a negative response within the first months of life is suggestive of a neurologic abnormality. From the results of one prospective and one retrospective study, it is clearly indicated that the absence of the plantar grasp reflex from 3 months of age and on correlates with the development of spastic cerebral palsy. The specific combination of presence or absence of specific primitive reflexes, postural reactions, or both may accurately predict a specific type of cerebral palsy or neurodevelopmental abnormality.     

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.