Age-related changes in oxygen saturation over the first year of life: A longitudinal study

Stability of oxygen saturation depends on maturation and function of individual components of the respiratory system. The aim of this study was to record and analyse comprehensive oxygen saturation data in a longitudinal study over the first year of life. Detailed sleep studies were performed on 15 normal infants eight times in the first year of life. The accrued oxygen saturation data were analysed on a computerized oximetry data analysis system. Results show the mean sleep saturation levels trending upwards and stabilizing by 185 days. There was an inverse curvilinear relationship between mean age and median desaturation time and the median number of desaturations at ≥95, ≥92 and ≥90% saturation. The mean cumulative desaturation time ≥90% in the first 4 months was 11.08 min (range 2.5–36.57 min). This study demonstrates monotonic patterns of increasing saturation and decreasing number and time of desaturations ≥95% and ≥90% but a random pattern of desaturations ≥85% occurs across the first 6 months of life. Cumulative desaturation times over the first 4 months of life were high and could be important to the development of maturity of the respiratory system. After 6 months, all indices of saturation and desaturation point to a stable and mature respiratory system.     

Low daytime pulse oximetry reading is associated with nocturnal desaturation and obstructive sleep apnea in children with sickle cell anemia

A retrospective medical record review was established to test the hypothesis that in children with sickle cell anemia (SCA), a daytime oxygen saturation (SpO(2)) 相似文献   

Obstructive sleep apnea in children with Down syndrome.

Children with Down syndrome have many predisposing factors for the obstructive sleep apnea syndrome (OSAS), yet the type and severity of OSAS in this population has not been characterized. Fifty-three subjects with Down syndrome (mean age 7.4 +/- 1.2 [SE] years; range 2 weeks to 51 years) were studied. Chest wall movement, heart rate, electroculogram, end-tidal PO2 and PCO2, transcutaneous PO2 and PCO2, and arterial oxygen saturation were measured during a daytime nap polysomnogram. Sixteen of these children also underwent overnight polysomnography. Nap polysomnograms were abnormal in 77% of children; 45% had obstructive sleep apnea (OSA), 4% had central apnea, and 6% had mixed apneas; 66% had hypoventilation (end-tidal PCO2 greater than 45 mm Hg) and 32% desaturation (arterial oxygen saturation less than 90%). Overnight studies were abnormal in 100% of children, with OSA in 63%, hypoventilation in 81%, and desaturation in 56%. Nap studies significantly underestimated the presence of abnormalities when compared to overnight polysomnograms. Seventeen (32%) of the children were referred for testing because OSAS was clinically suspected, but there was no clinical suspicion of OSAS in 36 (68%) children. Neither age, obesity, nor the presence of congenital heart disease affected the incidence of OSA, desaturation, or hypoventilation. Polysomnograms improved in all 8 children who underwent tonsillectomy and adenoidectomy, but they normalized in only 3. It is concluded that children with Down syndrome frequently in have OSAS, with OSA, hypoxemia, and hypoventilation. Obstructive sleep apnea syndrome is seen frequently in those children in whom it is not clinically suspected. It is speculated that OSAS may contribute to the unexplained pulmonary hypertension seen in children with Down syndrome.     

Nocturnal oximetry in infants with cystic fibrosis.

AIM: To investigate whether children with cystic fibrosis under 3 years of age have disordered breathing and episodes of oxygen desaturation during sleep. METHODS: We studied 19 infants (9 boys and 10 girls) with cystic fibrosis, mean age 13.1 months (range 3-36 months) and 20 age and sex matched healthy subjects. Patients and controls underwent an overnight polysomnographic study and respiratory function testing on the following morning. RESULTS: Seven patients with ongoing respiratory tract inflammation had disordered breathing and episodes of oxygen desaturation during sleep. Pulse oximetry showed a significantly lower mean oxygen saturation (SaO(2)) and a higher percentage of total sleep time spent with SaO(2) less than 93% in symptomatic children than in controls. CONCLUSION: Results suggest that infants and young children with cystic fibrosis and mild airways inflammation (rhinitis, cough, red throat) have episodes of oxygen desaturation during sleep.     

Changes in nocturnal oximetry after treatment of exacerbations in cystic fibrosis

Sleep related arterial oxygen desaturation has been described in clinically stable young adults with cystic fibrosis. The incidence and severity of nocturnal oxygen desaturation in children during infective exacerbations and the changes that occur with treatment were examined. Forty five children with proved cystic fibrosis, median age 8.9 years, admitted to the Regional Cystic Fibrosis Unit underwent clinical evaluation, spirometry, and measurement of peak flow and nocturnal oxygen saturation on admission and after 10 days' treatment. There was a significant improvement in all the above measurements, with the averaged overnight saturation changing from a mean (SD) 92.7 (2.7)% to 94.3 (2.0)%, mean (SE) difference 1.58 (0.37). The time spent with a saturation 4% or more below their clinic value showed a marked improvement from 122 (152) minutes on the first night to 21 (30.7) on the second, mean (SE) difference 101 (22.4). Eight young children could not perform pulmonary function tests, all desaturated on the admission night. Nocturnal hypoxaemia is a common finding in young cystic fibrosis patients during infective exacerbations but improves with treatment. Overnight oximetry is simple to perform, well tolerated, and identifies patients with marked nocturnal desaturation.     

Wheeze detection as a measure of bronchial challenge in young children with cough-variant asthma and with classic asthma

AIM: Tracheal and chest auscultation for wheeze and transcutaneous oximetry have both been suggested as outcome measures of bronchial provocation tests in young children. The aims of this study were to compare the sensitivity of these two techniques as endpoints for methacholine challenge in young children with cough-variant asthma (CVA) and with classic asthma (CA), and to investigate whether oxygen saturation levels at the presence of wheezing differ in these two groups. METHODS: We performed a retrospective analysis of methacholine challenge test data from 4- to 6-year-old children with CVA (n = 41) and from those with CA (n = 53). The challenges used a modified auscultation method that set wheeze detection and/or oxygen desaturation for determining the endpoint. RESULTS: The frequency of wheeze detection at the endpoint was significantly lower than that of oxygen desaturation (46.3% vs. 78.0%) in the CVA group, which contrasted with findings (75.5% vs. 50.9%) in the CA group. Oxygen saturation levels at the presence of wheezing were significantly lower in the CVA group than in the CA group (94.5 +/- 1.5% vs. 95.9 +/- 1.8%, p = 0.006). CONCLUSION: Wheeze detection is a less sensitive outcome measure than oxygen desaturation and is associated with a lower oxygen saturation level in young children with CVA, compared to those with CA.     

Changes in nocturnal oximetry after treatment of exacerbations in cystic fibrosis.

Sleep related arterial oxygen desaturation has been described in clinically stable young adults with cystic fibrosis. The incidence and severity of nocturnal oxygen desaturation in children during infective exacerbations and the changes that occur with treatment were examined. Forty five children with proved cystic fibrosis, median age 8.9 years, admitted to the Regional Cystic Fibrosis Unit underwent clinical evaluation, spirometry, and measurement of peak flow and nocturnal oxygen saturation on admission and after 10 days' treatment. There was a significant improvement in all the above measurements, with the averaged overnight saturation changing from a mean (SD) 92.7 (2.7)% to 94.3 (2.0)%, mean (SE) difference 1.58 (0.37). The time spent with a saturation 4% or more below their clinic value showed a marked improvement from 122 (152) minutes on the first night to 21 (30.7) on the second, mean (SE) difference 101 (22.4). Eight young children could not perform pulmonary function tests, all desaturated on the admission night. Nocturnal hypoxaemia is a common finding in young cystic fibrosis patients during infective exacerbations but improves with treatment. Overnight oximetry is simple to perform, well tolerated, and identifies patients with marked nocturnal desaturation.     

Pulse oximetry in very low birth weight infants with acute and chronic lung disease

With improved survival of very low birth weight infants, the incidence of bronchopulmonary dysplasia has significantly increased. Pulse oximetry appears to be an adequate alternative to transcutaneous PO2, for continuous arterial oxygen saturation (SaO2) monitoring in neonates; however, its usefulness has not been very well documented in very low birth weight infants. We studied 68 patients with birth weight less than 1,250 g; 44 neonates had respiratory distress syndrome and 24 had bronchopulmonary dysplasia. Using a Nellcor N-100 pulse oximeter, we compared transcutaneous oxygen saturation with simultaneous arterial samples analyzed for SaO2 (range 78% to 100%) using an IL 282 co-oximeter. Fetal hemoglobin was measured in 66 patients. We also evaluated the accuracy of transcutaneous PO2 in reflecting arterial PO2 in patients with bronchopulmonary dysplasia. Over a wide range of PO2, PCO2, pH, heart rate, BP, hematocrit, and fetal hemoglobin, linear regression analysis revealed a close correlation between pulse oximeter values and co-oximeter measured SaO2 in patients with acute (r = .88, Y = 19.41 + 0.79X) and chronic (r = .90, Y = 9.72 + 0.92X) disease. Regression analysis of transcutaneous v arterial PO2 in infants with bronchopulmonary dysplasia showed an r value of .78. In addition, in these patients with chronic disease, the mean difference between pulse oximeter SaO2 and co-oximeter measured SaO2 was 2.7 +/- 1.9% (SD); whereas the mean difference between transcutaneous and arterial PO2 was -14 +/- 10.7 mm Hg. Our findings indicate that pulse oximetry can be used reliably in very low birth weight infants with acute and chronic lung disease, for SaO2 values greater than 78%.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

Sleep quality in children with asthma treated with theophylline or cromolyn sodium

The effect of theophylline and cromolyn sodium on sleep was studied in 10 children with asthma who were 10 to 17 years of age (mean 13.5 +/- 2.4 years). Theophylline or cromolyn sodium was taken for 14 days in a double-blind, crossover, placebo-controlled trial. Theophylline blood levels before sleep were 10.2 +/- 4 micrograms/ml during the theophylline period. There was no difference in pulmonary function between the two periods. Theophylline did not disrupt sleep as measured by sleep latency, total sleep time, sleep efficiency, movement time, microarousals, and arousals. Apneic episodes (greater than or equal to 10 seconds) were of central origin and less frequent during the theophylline period (p less than 0.05). Arterial oxygen desaturation (greater than 5% decrease from baseline saturation when awake) was less frequent during the theophylline treatment (p less than 0.05). We conclude that theophylline treatment of the children's asthma did not disrupt sleep and appeared to have a protective effect in regard to apnea, hypopnea, and arterial oxygen saturation.     

Effects of child seats on the cardiorespiratory function of newborns

BACKGROUND: This study aims to determine the effect of differently positioned infant car seats on cardio-respiratory parameters in healthy full-term newborns. METHODS: We examined 15 healthy term newborns for respiratory compromise due to normal restraint in a recommended infant car seat. There are currently two types of car seats available in Japan: a chair-shaped car seat and a bed-shaped car seat. Using a sleep apnea recorder, we simultaneously monitored heart rate, percutaneous oxygen saturation, chest impedance and nasal airflow in infants placed in each of the car seats and also placed in the supine position on a nursery cot. Episodes of oxygen desaturation below 95% and longer than 10 s (mild desaturation) and below 90% longer and than 10 s (moderate desaturation) were evaluated over 30 min observation period. RESULTS: The amount of time infants spent in a sleep state was significantly longer in the car seats than it was on the cot (P = 0.0015 for bed-shaped, P = 0.0012 for chair-shaped) and there was no difference in this measure between the two types of car safety seats. Mean of oxygen saturation with the chair-shaped car seat (95.8%) was significantly lower than that with the bed-shaped car seat (98.8%) (P = 0.0008). Newborn infants laid on the cot showed no episodes of desaturation. Newborn infants placed in the chair-shaped car seat had significantly more episodes of mild desaturation (mean, 7.33 times in nine of 15 infants), whereas in the bed-shaped seat observed only once each in two infants (P = 0.008). Moderate desaturation was observed in four of 15 infants in the chair-shaped car seat, whereas not observed in the bed-shaped car seat (P = 0.068). CONCLUSION: The results suggest that prior to discharge the degree of oxygen desaturation that occurs when an infant is placed in a chair-style car seat should be checked.     

Transcutaneous oxygen saturation in sleeping infants: prone and supine.

Pulse oximetry was used to measure transcutaneous arterial oxygen saturation in infants aged 2 to 11 months prone and supine in quiet sleep. Groups of healthy infants (n = 34), infants with upper respiratory tract infections (n = 13), and infants with generalised moderately severe lower respiratory tract infections (n = 17) were studied. No clinically important differences were demonstrated in any of these groups, although there was a small advantage in the prone position in the group with lower respiratory tract infection. The effect of posture on infants with more severe lower respiratory tract infection and during active sleep has yet to be determined.     

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.     

肥胖儿童阻塞性睡眠呼吸暂停的临床特征

目的 研究肥胖儿童合并阻塞性睡眠呼吸暂停（obstructive sleep apnea，OSA）的临床特征。 方法 对在深圳市儿童医院呼吸科行多导睡眠监测的肥胖并诊断为OSA的33例7~15岁儿童的临床资料进行回顾性分析，并选取50例体重正常的、性别及年龄相匹配的OSA患儿作为对照组。 结果 33例合并肥胖的OSA儿童中，常见的日间症状前3位为：注意力不集中30例（91%），嗜睡22例（67%），晨起疲劳21例（64%）；夜间症状前3位为：打鼾27例（82%），张口呼吸20例（61%），出汗16例（48%）。与正常儿童参考值相比，肥胖OSA组和对照组两组患儿浅睡眠延长，深睡眠缩短，快速动眼期明显缩短，但两组之间这些指标的比较差异无统计学意义（P>0.05）。与对照组比较，肥胖OSA组呼吸暂停低通气指数和阻塞性呼吸暂停低通气指数均显著增加（P<0.05）；快速动眼期及非快速动眼期氧减指数均显著增加（P<0.05）；肥胖OSA组睡眠期间最低血氧饱和度显著低于对照组（P<0.05）。 结论 肥胖合并OSA儿童临床日间症状以注意力不集中、嗜睡、晨起疲劳为主，夜间症状以打鼾、张口呼吸、出汗为主。与体重正常OSA患儿相比，肥胖合并OSA儿童的睡眠结构无明显差别，但呼吸事件及血氧饱和度下降更严重。 引用格式:     

Neonatal pattern of breathing during active and quiet sleep after maternal administration of meperidine.

The aim of this study was to reappraise the effects of maternal meperidine administration on breathing pattern during the first hours of life taking into account the state of alertness. Because breathing instability is more pronounced during active sleep, we hypothesized that meperidine administration might create a greater risk for respiratory instability during active sleep, the prominent sleep state in newborns. We studied eight full-term, healthy newborns whose mothers had received a continuous i.v. infusion of meperidine (81 +/- 9 mg) that was terminated 5.5 +/- 2.1 h before delivery. These infants were compared with a control group of eight full-term newborns whose mothers did not receive any opioids. In both groups, all babies were delivered vaginally after a normal labor and had Apgar scores of 9 or 10 at 1 and 5 min. Neonatal gastric secretion and maternal venous and umbilical venous blood were sampled at delivery for determination of meperidine concentration. From 60 to 300 min after delivery, behavioral sleep states and thoracic and abdominal movement as well as transcutaneous arterial oxygen saturation (SaO2) were monitored continuously. The number of apneic spells lasting more than 3 s during 100 min of recording and the percentage of time with SaO2 below 90% in each sleep state were recorded. During quiet sleep, all respiratory variables were similar in both groups. During active sleep, there were significantly more apneic episodes (37.1 +/- 25.1 versus 11.2 +/- 13.9) and a higher percentage of time with SaO2 less than 90% (14.3 +/- 16.7% versus 1.3 +/- 1.5%) in the meperidine group than in the control group (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Nicotine delays arousal during hypoxemia in lambs

A decreased ability to arouse from sleep in response to arterial hypoxemia may lead to severe asphyxia and has been proposed as a mechanism of sudden infant death syndrome. Based on previous observations that nicotine exposure, a major environmental risk factor for sudden infant death syndrome, may impair hypoxic defense in neonates, we hypothesized that a short-term infusion of nicotine could impair hypoxic arousal through interference with oxygen-sensing mechanisms. Seven chronically instrumented unanesthetized lambs were studied at the age of 4.6 +/- 1.3 d during normoxia and acute hypoxia (0.1 fraction of inspired oxygen) for 5 min. Ventilation, transcutaneous Hb oxygen saturation, blood pressure, heart rate, and time to arousal were compared during a control saline infusion and during a 0.5 microg x kg(-1) x min(-1) nicotine infusion. Activity states, i.e. wakefulness and quiet sleep as well as arousal, were defined by EEG, nuchal electromyogram, and electrooculogram. Each lamb acted as its own control. Arousal from quiet sleep occurred significantly later during nicotine infusion compared with control (177 +/- 93 versus 57 +/- 41 s, p < 0.01) and at a lower transcutaneous Hb oxygen saturation (60 +/- 12 versus 79 +/- 12%, p < 0.01) (paired t test). The ventilatory response to hypoxia in wakefulness was similar during both conditions but was significantly attenuated in quiet sleep during nicotine infusion (p < 0.001, 2-way ANOVA repeated-measures design). Blood pressure and heart rate responses were similar during both conditions. These results suggest that a brief nicotine exposure blunts oxygen sensitivity in young lambs, a finding of potential relevance for sudden infant death syndrome.     

Oxygen saturation during the first 24 hours of life

AIM: To determine normative data for arterial oxygen saturation, measured by pulse oximetry (SpO2), in healthy full term infants throughout their first 24 hours of life. METHODS: Long term recordings of SpO2, pulse waveform, and breathing movements were made on 90 infants. Recordings were analysed for baseline SpO(2), episodes of desaturation (SpO2 /= four seconds, and periodic apnoea (>/= three apnoeic pauses, each separated by /= 20 seconds) were identified in six recordings. Four desaturations fell to 相似文献   

Association between gastroesophageal reflux and dips in the oxygen transcutaneous saturation of the hemoglobin in infants with chronic obstructive ventilatory disease

OBJECTIVE: To verify the association between oxygen desaturation episodes and the dips in pH in infants with chronic obstructive respiratory symptoms. METHOD: Cross-sectional study with children 24 months old or younger hospitalized for investigation of chronic obstructive respiratory symptoms from 1997 to 1999. The patients underwent esophageal pH monitoring associated with transcutaneous oxygen saturation during the night. The patients were included in the study according to their need to be hospitalized and availability of equipment. The indices used to measure this association were reflux index, total number of refluxes, number of refluxes longer than 5 minutes, Euler index, ZMD index, 24-hour mean pH, and mean pH of desaturation. RESULTS: We studied 44 children. The mean age was 7.5 months, and 20% had desaturation below 93% during pH monitoring. We used the t test to compare the occurrence of desaturation with the pH monitoring parameters. We found higher significance with the reflux index (RI), number of episodes longer than 5 minutes, ZMD index, 24-hour mean pH, and mean pH of desaturation. The bivariate analysis, taking into account possible confounding factors and RI, showed PR equal to 6.61 (IC 95% 1.67 - 26.12) for an RI higher than 4%. CONCLUSION: Oxygen saturation monitoring associated with pH monitoring may be a useful tool to establish an association between GER and respiratory problems in patients with chronic or recurrent wheeze.     

Noninvasive estimation of arterial oxygenation in newborn infants

Two noninvasive methods of estimating arterial oxygenation were compared in a group of 48 infants ranging in birth weight from 870 to 4,000 gm, with diagnoses including apnea of prematurity, hyaline membrane disease, meconium aspiration, and congenital heart disease. Both transcutaneous oxygen measurements and ear oximetry gave reasonably accurate estimations of arterial oxygen levels within commonly used clinical ranges (PO2 50 to 70 mm Hg, arterial saturation 90 to 98%). Infants with shock demonstrated a wide range of values for transcutaneous oxygen levels, suggesting that this method has limited usefulness in this situation. Ear oximetry had limited ability to distinguish high, but safe, levels of arterial oxygen from excessively elevated levels. While neither method can be recommended for replacement of arterial oxygen sampling, both methods may be useful in a clinical setting if care is exercised in interpretation of the results and if the values obtained are checked against those from arterial blood.     

Pulse oximetry in pediatric intensive care: comparison with measured saturations and transcutaneous oxygen tension

We evaluated a new pulse oximeter designed to monitor beat-to-beat arterial oxygen saturation (SaO2) and compared the monitored SaO2 with arterial samples measured by co-oximetry. In 40 critically ill children (112 data sets) with a mean age of 3.9 years (range 1 day to 19 years), SaO2 ranged from 57% to 100%, and PaO2 from 27 to 128 mm Hg, heart rates from 85 to 210 beats per minute, hematocrit from 20% to 67%, and fetal hemoglobin levels from 1.3% to 60%; peripheral temperatures varied between 26.5 degrees and 36.5 degrees C. Linear correlation analysis revealed a good agreement between simultaneous pulse oximeter values and both directly measured SaO2 (r = 0.95) and that calculated from measured arterial PaO2 (r = 0.95). The device detected several otherwise unrecognized drops in SaO2 but failed to function in four patients with poor peripheral perfusion secondary to low cardiac output. Simultaneous measurements with a tcPO2 electrode showed a similarly good correlation with PaO22 (r = 0.91), but the differences between the two measurements were much wider (mean 7.1 +/- 10.3 mm Hg, range -14 to +49 mm Hg) than the differences between pulse oximeter SaO2 and measured SaO2 (1.5% +/- 3.5%, range -7.5% to -9%) and were not predictable. We conclude that pulse oximetry is a reliable and accurate noninvasive device for measuring saturation, which because of its rapid response time may be an important advance in monitoring changes in oxygenation and guiding oxygen therapy.