Effect of position on oxygen saturation and requirement in convalescent preterm infants

Aims: To document the effect of position on oxygen saturation and changes in oxygen requirement in convalescent preterm infants. Methods: Twelve infants born ≥24 and ≤32 weeks gestation, extubated and without congenital anomaly were studied using nap polysomnography in prone and supine, twice weekly until discharge. Mean oxygen saturation (SpO₂), minimum SpO₂, mean minimum SpO₂ and time with SpO₂ < 90% were measured in active sleep. Results: Eight male and four female infants [median gestation 28 (24–31) weeks and median birthweight 1059 (715–1840) g] had 39 studies. For 21 of 39 studies, the infant was on respiratory support. Four infants had chronic lung disease (CLD). SpO₂ varied with postmenstrual age (PMA) (p = 0.003) but not with position (p = 0.36), and PMA did not influence the effect of position on SpO₂ (p = 0.19). SpO₂ was lower for those with CLD (p < 0.0001) and those on respiratory support (p < 0.001), but there was no effect of position (p = 0.97 and p = 0.67, respectively). From 36 weeks PMA, a change to supine did not increase oxygen requirement. Conclusion: In preterm infants, PMA and residual respiratory disease have greater effects on oxygenation than position. A supine sleep position is not disadvantageous for preterm infants at discharge.     

Awake daytime oximetry measurements in the management of infants with chronic lung disease

OBJECTIVE: To assess the value of 1-h daytime awake oximetry as a means of weaning oxygen flows in infants with oxygen dependent chronic lung disease. METHODS: A cohort study of oxygen dependent infants enrolled in a 3-month period. One hour of awake oximetry data were compared with equal time periods defined within a polysomnographic study and at the same oxygen flow rate. Sensitivity results were derived from the decision to wean oxygen to a lower flow or air. RESULTS: Twenty-two infants were enrolled and 27 studies were performed. The infants that could be weaned had an awake median of mean oxygen saturations of 97% and spent 14% of the time < or = 95% but only 2% < or = 92%, while for those not weaned, the awake median of mean oxygen saturations was 94% with 43% of their time < or = 95% and 26.8% < or = 92% saturation. CONCLUSIONS: Daytime oximetry can predict the outcome of polysomnography with a sensitivity of 100% and a specificity of 65%, and could be used to wean oxygen or as a screening tool for polysomnographic studies in infants with chronic lung disease provided there are reasonably long periods of monitoring and mean oxygen saturations above 95%.     

Oxygen saturation during sleep in patients with bronchopulmonary dysplasia.

We hypothesized that significant sleep desaturation might occur in infants with bronchopulmonary dysplasia whose awake saturations were between 90 and 92%. Supplemental oxygen was continued until the awake saturation on room air was 90% or greater. Sleep saturations were monitored by oximetry sampling for a 3-min period every hour overnight. Significant desaturation was considered to be present if the saturation fell repeatedly below 88%. There were 39 studies performed in room air, and 14 studies in supplemental oxygen. We demonstrated that patients with acceptable awake saturation may desaturate while sleeping. However, only 1 of 25 patients whose saturation in room air was 92% or more repeatedly desaturated during sleep.     

The use of overnight oximetry in neonates: A literature review

There is much debate between neonatologists and paediatricians about appropriate oxygen saturation targets for babies with chronic neonatal lung disease (CNLD). Overnight oximetry is used to guide the fraction of inspired oxygen to use. We did this literature review to examine the current literature on the use of overnight oximetry in term infants, preterm infants and babies with CNLD (especially relevant to ex‐preterm babies with CNLD going home on oxygen). We reviewed the literature from January 1990 to October 2017 by searching the following databases: Cochrane Central Register of Controlled Trials, The Joanna Briggs Institute, CINAHL, MEDLINE, Scopus, EMBASE, ProQuest and Science Direct. Sixteen articles were included in the review. The literature available on overnight oximetry in neonates is limited, it is not contemporary, and it reports studies that did not use oximeters with modern software for data collection and analysis. It is imperative that reference ranges be defined for overnight oximetry parameters so that babies are not inadvertently administered inappropriate amounts of oxygen.     

Oxygen Saturation Immediately after Birth in Infants Delivered in Tertiary Care Hospital in India

Objective

To study the sequential changes in SpO₂ values in newborns delivered in a teaching hospital in India.

Methods

Full-term infants born by normal vaginal delivery to registered mothers at KLE University Hospital, Belgaum with birth weight more than 2,500 g, no congenital anomalies and who had received only routine care at birth were included in the study. After delivery, newborn infants were placed on a resuscitation trolley under a radiant warmer; the oxygen saturation sensor was attached (Nellcor DURA-Y multisite oxygen sensor) and then connected to the monitor (Planet 55 multiparameter recorder).

Results

The mean (SD) gestational age of infants included in the study was 38.8 (1.1) wk and birth weight was 2,800 (300) g. The median (IQR) oxygen saturation level (SpO₂) at 2 min of age was 69 % (68 %–79 %). The median level of SpO₂ at 90 % and 95 % saturation was attained at 6.5 min and at 11 min of life, respectively.

Conclusions

Infants delivered in resource poor facilities of developing countries take 11 min to reach 95 % saturations after birth but they are within the reference range values of Neonatal Resuscitation Program 2010 guidelines.     

Transcutaneous monitoring of oxygenation: what is normal?

We examined 55 infants on 119 occasions, from birth to 6 months, to obtain normal data and to establish guidelines for the management of oxygen-dependent infants with chronic lung disease. Transcutaneous oxygen tension (tcPo2) and saturation (tcSao2) were monitored during four states: awake, feeding, quiet sleep, and active sleep. Lowest values (mean +/- SD) for tcSao2 were recorded in all states during the first week of life: awake 96.2% +/- 2.6%, feeding 91.2% +/- 3.7%, quiet sleep 93.2% +/- 2.9%, and active sleep 92.1% +/- 2.9%. After the first week the results were affected by state rather than age, with differences observed between awake and feeding (P less than 0.0001), awake and asleep (P less than 0.00001), and quiet sleep and active sleep (P less than 0.001). The findings for tcPo2 were less consistent and probably affected by the characteristics of skin. In the first week, values were as follows: awake 83.5 +/- 10.1 mm Hg, feeding 73.4 +/- 10.1 mm Hg, quiet sleep 78.5 +/- 10.9 mm Hg, and active sleep 73.4 +/- 11.4 mm Hg. Subsequently, only the state effect remained, and significant differences existed between awake and feeding (P less than 0.0001) and awake and asleep (P less than 0.00001). We conclude that transcutaneous blood gas measurements are affected by state of the infant.     

Prone or supine for infants with chronic lung disease at neonatal discharge?

OBJECTIVE: To determine whether infants with chronic lung disease (CLD), ready for neonatal unit discharge, maintain cardiorespiratory stability while sleeping supine. METHODS: Subjects were 15 infants born < 32 weeks gestational age (GA) and ready for discharge from the regional tertiary neonatal intensive care unit. Polysomnography recordings of sleep state, heart rate, arterial oxygen saturation, respiratory effort and nasal/oral airflow were taken prone and supine for up to 3 h post feed with the first position randomly allocated. The main outcome measures were oxygen saturation and apnoea hypopnoea index (AHI). RESULTS: Seven infants (median GA 27 weeks, birthweight 945 g) had CLD and eight infants (median GA 29 weeks, birthweight 1160 g) did not. CLD infants were more mature at study than non-CLD infants (median 39 vs 36 weeks, P = 0.019). Neither oxygen saturation nor AHI were position dependent and no group differences were noted with respect to CLD status. There was a significant interaction of GA and sleep position with less-mature infants spending less time in quiet sleep (QS) in supine position (P = 0.006). These less-mature infants also had a higher AHI (P = 0.033). As expected, the AHI and arousal index (AI) were higher in active sleep (P < or = 0.001, P = 0.013, respectively) and mean oxygen saturation was lower (P = 0.001). CONCLUSIONS: The supine position appears appropriate for very preterm infants with CLD going home from the neonatal unit. Respiratory instability on neonatal discharge is more likely to be associated with immaturity than CLD.     

Nocturnal haemoglobin oxygen saturation variability is associated with vitamin C deficiency in Tanzanian children with sickle cell anaemia

Aim: To compare pulse oximetry in children with sickle cell anaemia (SCA) and controls and test the hypothesis that vitamin C deficiency (VCD; <11.4 μmol/L) is associated with nocturnal haemoglobin oxygen desaturation in SCA. Methods: We undertook nocturnal and daytime pulse oximetry in 23 children with SCA (median age 8 years) with known steady‐state plasma vitamin C concentrations and 18 siblings (median 7 years). Results: Median nocturnal delta 12 s index (delta12 s), a measure of haemoglobin oxygen saturation (SpO₂) variability, was 0.38 (interquartile range 0.28–0.51) in SCA and 0.35 (0.23–0.48) in controls, with 9/23 and 6/18, respectively, having a delta12 s >0.4, compatible with obstructive sleep apnoea (OSA). Eleven of twenty‐three with SCA had VCD; logged vitamin C concentrations showed a 66% decrease per 0.1 unit increase in delta12 s ([95% CI ?86%, ?15%]; p = 0.023) and delta12 s >0.4 was associated with VCD (odds ratio 8.75 [1.24–61.7], p = 0.029). Daytime and mean nocturnal SpO₂ were lower in SCA but there was no association with vitamin C. Conclusion: Obstructive sleep apnoea (OSA), detected from nocturnal haemoglobin oxygen saturation variability, is common in Tanzanian children and associated with vitamin C Deficiency in SCA. The direction of causality could be determined by comparing OSA treatment with vitamin C supplementation.     

Arterial oxygen saturation in healthy term neonates

Our objective was to determine arterial oxygen saturation as measured by pulse oximetry (SpO₂) in healthy term neonates during their first 4 weeks of life. Overnight recordings of SpO₂ (Nellcor N200), photoplethysmographic (pulse) wave-forms from the oximeter and breathing movements were performed in 60 term infants. They were studied initially during their 1st week of life (median age 4 days, range 1–7) and then again during their 2nd–4th week (median age 17 days, range 8–27). Median baseline SpO₂, measured during regular breathing, was 97.6% (range 92–100) during week 1 versus 98.0% (86.6–100) during week 2–4 (P>0.05). Episodes of desaturation, defined as a fall in SpO₂ to 80% for 4 s, were found in 35% of recordings obtained in week 1 compared to 60% of those obtained in week 2–4 (P<0.01). Their frequency increased from a median of 0 (0–41) per 12 h of recording at the initial recording to 1 (0–165) at follow up (P<0.01). Analysis of the data by week of life showed a peak in desaturation frequency in the 2nd week of life. The infants with extreme values at follow-up (e.g. a baseline SpO₂ of 86.6%, 5th percentile 91.9%, or a desaturation frequency of 165 per 12 h of recording, 95th percentile 32) had had values well within the normal range during their initial recording (a baseline SpO₂ of 94.4%, or a desaturation frequency of 4). Most of the desaturations in the infants with extreme values were associated with periodic apnoea. These results demonstrate only relatively minor developmental changes in oxygenation in term neonates during the first 4 weeks of life. The clinical significance of outlying values, i.e. a low baseline SpO₂ or a high number of episodic desaturations, remains to be determined.Conclusion These healthy term neonates had values for baseline oxygen saturation and desaturation frequency that were not substantially different from those observed in older infants.     

The effects of swaddling on oxygen saturation and respiratory rate of healthy infants in Mongolia

BACKGROUND: Infant swaddling is common practice in some developing countries where infant respiratory morbidity is also prevalent. Little is known about the effect of swaddling on respiratory variables in healthy infants. Such information could have important implications for respiratory diseases. AIMS: To compare respiratory rates (RR) and arterial oxygen saturations (SaO2) of healthy swaddled infants and non-swaddled infants during different conditions of sleep and arousal. SETTING: Community based, nested case control study in Ulaanbaatar, Mongolia. SUBJECTS AND METHODS: Habitually swaddled and non-swaddled infants aged 9-10 weeks taking part in a randomised controlled trial of swaddling. Respiratory rate and SaO2 were measured during quiet wakefulness, feeding, quiet and active sleep. Habitually swaddled infants were studied in swaddled and non-swaddled conditions. Habitually non-swaddled infants were studied only in the non-swaddled state. RESULTS: SaO2 was higher during awake states compared with sleep states in all groups of infants. Habitually swaddled infants had lower mean SaO2 in the swaddled compared with non-swaddled condition (96.5% vs. 96.9%, p < 0.01) but these were not significantly different from the mean SaO2 of non-swaddled infants (96.9%, minimum p = 0.22). Habitually swaddled infants in the swaddled and non-swaddled states had similar respiratory rates, but these were, in both cases, significantly lower than in habitually non-swaddled infants. CONCLUSION: Swaddling has little or no clinical effect on SaO2 or respiratory rates in healthy 9-10-week-old infants in Mongolia.     

Sleep organization and energy expenditure of breast-fed and formula-fed infants.

Sleep organization of infants may be influenced by differences in nutrient intakes from human milk and formula. Because sleep/awake and sleep stage patterns affect energy expenditure, we hypothesized that differences in sleep organization between breast-fed and formula-fed infants might account in part for differences in energy expenditure between feeding groups. Sleep stages and cycling of 4-mo-old breast-fed (n = 10) formula-fed (n = 10) infants were studied with simultaneous measurements of energy expenditure. EEG, electrooculogram, body movement by triaxial accelerometry, heart rate, and oxygen saturation were monitored during an overnight sleep session. Sleep stages, nonrapid eye movement (NREM), and rapid eye movement (REM) were determined. Behavioral observations were recorded by video tape and by a technologist. Oxygen consumption and carbon dioxide production were measured with an indirect calorimeter. Total number and duration of sleep cycles, REM latency, number of NREM and REM epochs, and duration of NREM epochs did not differ between feeding groups. Sleep latency was shorter (p < 0.05) and duration of REM epochs longer (p < 0.01) in the formula-fed group. Formula-fed infants spent a higher percentage of sleep time in REM compared with the breast-fed infants (42 versus 34%) (p < 0.003). Conversely, breast-fed infants spent a higher percentage of sleep time in NREM sleep and their heart rates during sleep were lower (114 versus 126 bpm; p < 0.01). Energy expenditure during REM sleep was 13.0 +/- 4.4% higher than during NREM sleep (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Oxygen metabolism and oxygenation of the newborn

The premature infant is to some extent protected from hypoxia, however defense against hyperoxia is poorly developed. The optimal assessment of oxygenation is to measure oxygen delivery and extraction. At the bedside PaO₂ and SpO₂ are approximations of oxygenation at the tissue level. After birth asphyxia it is crucial to know whether or not to give oxygen supplementation, when, how much, and for how long. Oxygen saturation targets in the delivery room have been studied, but the optimal targets might still be unknown because factors like gender and delayed cord clamping influence saturation levels. However, SpO₂ > 80% at 5 min of age is associated with favorable long term outcome in preterm babies.Immature infants most often need oxygen supplementation beyond the delivery room. Predefined saturation levels, and narrow alarm limits together with the total oxygen exposure may impact on development of oxygen related diseases like ROP and BPD. Hyperoxia is a strong trigger for genetic and epigenetic changes, contributing to the development of these conditions and perhaps lifelong changes.     

Oxygen saturation (SpO2) targeting for newborn infants at delivery: Are we reaching for an impossible unknown?

For more than 200 years, pure oxygen was given ad libitum to newborn infants requiring resuscitation. Due to oxidative stress and injury concerns, a paradigm shift towards using “less” oxygen, including air (21% oxygen) instead of pure (100%) oxygen, occurred about twenty years ago. A decade later, clinicians were advised to adjust fractional inspired oxygen (FiO₂) to target oxygen saturations (SpO₂) that were derived from spontaneously breathing, healthy, mature infants. Whether these recommendations are achievable, beneficial, harmful or redundant is uncertain. The underlying pathology leading to resuscitation varies between infants and may considerably alter an infant's response to supplemental oxygen. In this review, we summarize available evidence for the use of SpO₂ monitoring at delivery for newborn infants, elucidate existing knowledge and service gaps, and suggest future research recommendations that will lead to the safest clinical strategies for this standard and important practice.     

Sleeping through the night: a developmental perspective.

This study examines falling asleep and night waking in human infants during the first 8 months of life. All-night time-lapse video recordings were obtained at 3 weeks and 3 months of age; a Sleep Habits Interview was completed at these ages and repeated at 8 months of age by telephone interview. At the 3-week and 3-month ages, self-report measures of maternal psychologic distress, depression, and self-esteem were also obtained. The data are examined from both cross-sectional (age group) and longitudinal (individual) perspectives. Parent-infant interactions at bedtime and during the middle of the night changed significantly with increasing age. At 3 weeks of age, most infants were put into their cribs for the night already asleep. When they awakened in the middle of the night, they were removed from their cribs. By the time they returned to their cribs, they were again asleep. By 3 months of age, infants who were put into the crib awake at bedtime and allowed to fall asleep on their own were more likely to return to sleep on their own after awakenings later in the night. In contrast, infants who were put into the crib already asleep at the beginning of the night were significantly more likely to be removed from the crib following a subsequent nighttime awakening. Thus, the pattern of bedtime sleep onset was related to sleep onset following an awakening in the middle of the night. This association was present at 8 months as well.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection of sleep associated dysfunctional pharyngeal obstruction in infants

Six infants were referred with symptoms and clinical signs suggesting airway obstruction during sleep. In each case, overnight recordings of arterial oxygen saturation, respiratory movements and end tidal expired carbon dioxide (ETCO₂) showed the presence of abnormal episodes of hypoxaemia related to partial or complete airway obstruction and associated with a specific pattern of the inspiratory movement waveforms. These events and patterns were not found on recordings from 20 age-matched healthy infants and young children. ETCO₂ levels were also abnormally elevated in all six patients when asleep. Fiber-optic upper airway endoscopy excluded structural abnormalities, including significant tonsillar or adenoidal enlargement, but showed an intermittent dysfunctional inspiratory obstruction in the pharynx. Continuous positive airways pressure and tracheostomy were effective in treating this obstruction.Abbreviations CPAP continuous positive airways pressure - ETCO₂ end tidal carbon dioxide - SaO₂ arterial oxygen saturation     

Respiratory Water Loss in Relation to Activity in Fullterm Infants on Their First Day after Birth

ABSTRACT. Respiratory water loss (RWL), oxygen consumption and carbon dioxide production were measured in ten fullterm infants on their first day after birth, using an open flow-through system with a mass spectrometer, specially equipped with a water channel, for analysis of gas concentrations. Measurements were made both with the infant asleep and during different levels of motor activity. The ambient temperature was maintained at approximately 32.5°C and the ambient relative humidity at 50%. RWL increased from 4.2±0.7 (SD) mg/kg min when the infant was asleep to 6.3±1.0 mg/kg min when he or she was awake but calm; with increasing activity there was a further increase in RWL. The oxygen consumption increased from 5.4±0.9 (SD) ml/kg min during sleep to 6.9±0.8 (SD) ml/kg min when awake, and also increased further with increasing activity.     

Percentiles of oxygen saturations in healthy term newborns in the first minutes of life

The aim of this study was to establish the reference values of preductal oxygen saturation (SpO₂) in healthy infants immediately after birth. SpO₂ recordings of 200 term neonates (vaginal group;n=150 and cesarean group;n=50) with regular respiratory pattern were evaluated. The median SpO₂ values in the first, fifth and tenth minutes were 71, 92, and 98% in vaginal deliveries and 70, 79, and 96% in cesarean deliveries, respectively. SpO₂ was significantly lower in the cesarean group at any time after the first minute of life (p<0.0001). The time needed to reach a SpO₂>90% was three times longer in cesarean deliveries. Healthy neonates are poorly saturated immediately after birth. The duration to reach a SpO₂>90% was longer in infants born by cesarean deliveries. This study was supported by The Marmara University Scientific Research Committee (SAG-TUS-200906-0165). Presented as a poster in Hot Topics in Neonatology 2006, Washington, DC, 2–5 December 2006.     

Oxygen saturation by pulse oximetry in healthy infants at an altitude of 1610 m (5280 ft). What is normal?

Pulse oximetry is a valuable, noninvasive technique for assessing oxygen saturation that has gained wide clinical acceptance despite little available information concerning normal values in the newborn, especially at an altitude different than sea level. We performed serial pulse oximetry studies on 150 term, appropriate-weight-for-gestational-age, clinically healthy infants at an altitude of 1610 m (5280 ft) at 24 to 48 hours, 1 month, and 3 months of age to define a reference range for oxygen saturation as a guideline in clinical care. We found that mean oxygen saturation at 24 to 48 hours of age is 92% to 93% and varies little with infant activity. With increasing postnatal age, there is a tendency for increased oxygen saturation during the awake states to 93% to 94%, while oxygen saturation during sleep stays the same or even decreases slightly. The lower end of the reference range (2 SDs below the mean) is as low as 85% during feeding at 24 to 48 hours of age, and as low as 86% during quiet sleep at 1 and 3 months of age, with 88% to 89% the lower limit in other activities at all ages.     

Respiratory rate and severity of illness in babies under 6 months old.

This paper defines the normal range of respiratory rate in babies under 6 months of age. It was counted by two observers in 1007 babies of whom 709 were seen when presenting to hospital for assessment of an acute illness, and 298 on a random basis at home. Whether they were asleep, content, or crying was recorded and the severity of their illness graded. The diagnosis was also recorded. The mean (SD) for the respiratory rate in babies seen awake was 61 (18) breaths/minute at hospital and 61 (14) breaths/minute at home. The respiratory rate when awake did not correlate with the severity of a baby''s illness or the presence of serious lower respiratory tract infections. Sleeping babies had a significantly lower mean rate than awake babies at 42 (12) breaths/minute. Crying babies had a significantly lower mean rate than awake and content babies: 51 (14) breaths/minute compared with 61 (18) breaths/minute.