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.     

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.     

Diffusing capacity for carbon monoxide (T(LCO)) and oxygen saturation during exercise in patients with cystic fibrosis]

OBJECTIVES:To estimate the value of diffusing capacity for carbon monoxide (T(LCO)) in patients with cystic fibrosis and to evaluate its ability to predict arterial desaturation during exercise. METHOD: Fourty-four patients (9-30 years) with cystic fibrosis performed pulmonary function tests with measure of T(LCO) and a bicycle incremental exercise test. They represent a wide variation in disease severity: mean Shwachman score: 77.8 (range: 40-100), mean FEV1%: 72.8 (range: 17-131). This study investigated the relationship between T(LCO), lung volumes and exercise data. RESULTS: T(LCO) remained normal for a long time in patients with cystic fibrosis: 82% of them show a normal T(LCO) (mean value: 91.3% of predicted). T(LCO) was significantly correlated with FEV(1), residual volume, maximal work load and maximum oxygen uptake. A fall in arterial oxygen saturation was uncommon in our study (five patients) and not significantly correlated with T(LCO). CONCLUSIONS: T(LCO) is a good criter of severity of cystic fibrosis but remains unreliable to predict values above which physical activity is safe, without arterial desaturation. Exercise tests should be proposed in order to evaluate exercise adaptation of each patient and determine which factor limits maximal performance.     

Two minute walking distance in cystic fibrosis.

We have evaluated the ''two minute walking distance'' in children with cystic fibrosis as an objective measurement of exercise tolerance. There was a strong correlation between walking distance and height in 89 normal children (r = 0.72). Fifty children with cystic fibrosis showed a similar correlation (r = 0.56) with a mean result of 94% of that expected for height compared with the normal children. There was a training effect in the normal children with the second walk being significantly better than the first, but this was not evident in children with cystic fibrosis. The test was reproducible with no significant change in 12 children retested after one to three months. Sixteen children with cystic fibrosis admitted for treatment of chest disease showed a significant improvement in walking distance with treatment. Children as young as 5 years old can perform a walking distance test. It seems to be an objective way of assessing exercise tolerance and can help in evaluating response to treatment.     

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.     

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.     

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   

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.     

Association of Epstein-Barr virus infection and pulmonary exacerbations in patients with cystic fibrosis.

We observed severe pulmonary exacerbations during primary Epstein-Barr virus (EBV) infection in adolescent patients with cystic fibrosis. Since EBV is not a known respiratory tract pathogen in cystic fibrosis, we studied retrospectively all EBV-susceptible patients ages 6 to 18 years with chronic Pseudomonas respiratory tract colonization hospitalized for a pulmonary exacerbation during an 18-month period. Patients with serologic evidence of primary EBV infection (n = 5) were compared to control patients without EBV (n = 7). Before admission the groups had similar pulmonary function tests, clinical scores and frequency of hospitalization. On admission patients with EBV had significant weight loss, lower pulmonary function tests and lower clinical scores compared with controls. All remained significantly different 6 months after admission. Frequency of exacerbations requiring hospitalization increased after EBV infection but remained unchanged in controls. Primary EBV infection can be associated with severe pulmonary exacerbations and subsequent deterioration in clinical course in cystic fibrosis patients.     

Role of respiratory syncytial virus in early hospitalizations for respiratory distress of young infants with cystic fibrosis

To determine the frequency of respiratory syncytial virus (RSV) as the cause of hospitalization for acute pulmonary exacerbations in young infants with cystic fibrosis (CF), and to assess the clinical effects of RSV infections, we prospectively followed 48 children with a diagnosis of CF after identification by newborn screening. At a mean follow-up age of 28.8 months (range 5 to 59), 18 infants (38%) had been hospitalized a total of 30 times for acute respiratory distress. At the time of admission, 18 infants (60%) were less than 12 months, 8 (27%) between 12 and 24 months, and 4 more than 2 years of age. The RSV was identified in seven hospitalized infants, as determined by fluorescent antibody, immunoassay, or culture. Before admission with RSV infection, one of the seven infants had chronic respiratory signs, none had Brasfield chest x-ray scores below 20, and a previous throat culture was positive for Staphylococcus aureus in one infant. Hospitalizations were prolonged (mean duration 22 days), and were characterized by significant morbidity, with three infants (43%) requiring mechanical ventilation and five infants (71%) requiring home oxygen therapy for persistent hypoxemia at discharge. At a mean follow-up age of 26 months, these infants more frequently have chronic respiratory signs (p less than 0.01) and lower chest radiograph scores (p less than 0.05) than other CF infants. These findings demonstrate that RSV is an important cause of early acute respiratory tract morbidity in young infants with CF, and suggest the need for studying new strategies to implement early and aggressive antiviral therapy in young infants with CF.     

Prospective controlled study of home and hospital therapy of cystic fibrosis pulmonary disease

A controlled prospective study was undertaken to compare the efficacy and benefits of home and hospital treatment for patients with exacerbations of pulmonary disease caused by cystic fibrosis. A total of 41 home and 41 hospital treatments were analyzed. Home and hospital patients were matched according to sex, age, pulmonary function tests, and arterial blood gas values. Both home and hospital treatments resulted in statistically significant improvement in pulmonary function. A comparison of these values did not show any statistically significant difference between groups at admission or discharge. Furthermore, the mean number of treatment days for both groups, individually determined by the primary physician, was equivalent (home 17.7 +/- 1.1 days, hospital 18.1 +/- 4.1). The mean charge for a home treatment was approximately $10,000, and for a hospital treatment $18,000. Sixty-five percent of home care patients and 68% of hospital patients required retreatment for pulmonary exacerbations within the study period; the interval between pulmonary exacerbations for the two groups was not significantly different. In addition, 85% of patients receiving treatment at home were able to maintain at least some of their school or work activities. These data indicate that home therapy for cystic fibrosis patients with pulmonary exacerbations is less costly and is as effective as in-hospital therapy.     

Hemoglobin desaturation during sleep and daytime in patients with cystic fibrosis and severe airway obstruction

Transcutaneous hemoglobin saturation by pulse oximetry was evaluated during sleep and for 2-3 h during the day in 31 patients with cystic fibrosis (median age 15.2 years; range 7.6-33.6 years) and severe airway obstruction. Pulse oximetry readings were analyzed as a cumulative percentage of time in which oxygen saturation was < 90% during both sleep and daytime. Each patient was also examined using clinical and radiological scores, spirometry and arterial blood-gas analysis. The agreement between arterial and transcutaneous saturation was evaluated in 29 patients. The difference between transcutaneous and arterial saturation was 2.4 +/- 2.0% and it increased as arterial saturation decreased. Clinical and radiological scores and spirometry parameters showed a poor correlation with both overnight and daytime desaturation. An arterial saturation < 94% may indicate a risk of consistent desaturation. This occurred for more than 50% of the time in 11 of 20 patients during sleep and in 5 of 20 patients during daytime hours.     

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.     

A two-year randomized, placebo-controlled trial of dornase alfa in young patients with cystic fibrosis with mild lung function abnormalities.

OBJECTIVE: Our objective was to determine whether long-term treatment of young patients with cystic fibrosis (CF) with dornase alfa maintains lung function and reduces respiratory tract exacerbations. STUDY DESIGN: This was a 96-week, randomized, double-blind, placebo-controlled trial involving 49 CF centers. Inclusion criteria were age 6 to 10 years and forced vital capacity > or = 85% predicted. Patients were excluded for hospitalization for complications of CF within 2 months and use of dornase alfa within 6 months. Patients were treated with dornase alfa 2.5 mg or placebo once daily with a jet nebulizer and a compressor. RESULTS: Patients were randomized, 239 to dornase alfa and 235 to placebo. At baseline the mean age was 8.4 years, the mean forced expiratory volume in 1 second 95% predicted, the mean forced expiratory flow, midexpiratory phase 85% predicted, and the mean forced vital capacity 102% predicted. At 96 weeks the treatment benefit for dornase alfa compared with placebo in percent predicted (mean +/- SE) was 3.2 +/- 1.2 for forced expiratory volume in 1 second (P =.006), 7.9 +/- 2.3 for forced expiratory flow between 25% and 75% of vital capacity (P =.0008), and 0.7 +/- 1.0 for forced vital capacity (P =.51). The risk of respiratory tract exacerbation was reduced by 34% in patients who received dornase alfa (relative risk 0.66, P =.048). There was no statistically significant difference between the groups in changes in weight-for-age percentile. Adverse event profiles for the treatment groups were similar. CONCLUSIONS: Treatment of young patients with CF with dornase alfa maintains lung function and reduces the risk of exacerbations over a 96-week period.     

Night-to-night variability of polysomnography in children with suspected obstructive sleep apnea

OBJECTIVES: To determine whether a single polysomnographic night was a valid measure of obstructive sleep apnea syndrome (OSAS) in children with symptoms of sleep-disordered breathing. STUDY DESIGN: The night-to-night variability of respiratory and sleep parameters was measured prospectively in 30 snoring children aged 1.6 to 11.3 years (mean +/- SD, 4.1 +/- 2) by using 2 nocturnal polysomnograms performed 7 to 27 days apart (14 +/- 5 days). RESULTS: The mean of the respiratory variables including apnea index, apnea/hypopnea index, arterial oxygen saturation, and end-tidal partial pressure of carbon dioxide were not significantly different from night to night. Among the sleep parameters, there was no significant night-to-night difference in sleep efficiency, arousal index, percent rapid eye movement, or percent of slow wave sleep. Only the percentage of stage 2 was significantly different between the nights. The polysomnographic clinical diagnosis remained the same on both nights for all children, although the disease severity differed slightly in 2 patients. CONCLUSIONS: There is little clinically significant night-to-night variability in pediatric polysomnography, and no first-night effect. These data suggest that a single polysomnographic night is an adequate measure of the OSAS in children with symptoms of sleep-disordered breathing.     

Supplemental nasogastric feeding in cystic fibrosis patients during treatment for acute exacerbation of chest disease

The use of overnight, nasogastric, nutritional supplementation during hospitalization of children with cystic fibrosis (CF) receiving antibiotic therapy for acute exacerbations of respiratory disease was evaluated in 11 children (mean age = 7.75 years). Supplementary feeding significantly increased inpatient energy intake from 116 +/- 30% to 165 +/- 30% (P less than 0.001) of recommended dietary allowance with minimal effect on oral intake. It also resulted in significantly improved weight gains but neither increased energy intakes nor weights were sustained at short-term (mean = 5.7 weeks) or long-term (mean = 21.6 weeks) follow-up. The notion that short bursts of nasogastric feeding for inpatients with CF improve growth status is not supported. However, the study did show that treatment of chest infections alone does not positively affect spontaneous oral energy intake.     

Early detection of lung disease in children with cystic fibrosis using lung function

Measurement of lung function is routine in older children and adults with cystic fibrosis (CF) but not in infants and preschool children. Pulmonary infection, neutrophil-dominated inflammation and clinical exacerbations in young children similar to those seen in older subjects have been identified and highlight the urgent need to evaluate lung function in early life. Mounting evidence suggests lung function techniques sensitive to changes in peripheral lung function may be required to detect the early functional abnormalities in infants and preschool children with CF. In addition, the majority of studies in young children with CF have not reported longitudinal data and therefore the prognostic potential of existing lung function methods to track disease progression is poorly understood. This review aims to describe recent research findings in infants and preschool children and to outline currently available lung function techniques, issues around their standardization and their relative advantages and disadvantages in young children with CF.     

Nocturnal enuresis is a common complication following cardiac transplantation

Aims: To investigate the incidence of nocturnal enuresis post-cardiac transplantation. Methods: Seventy two cardiac transplantations have been performed in children under 16 years of age. All recipients who were alive and over 4 years of age at the time of the study received a questionnaire about urinary symptoms; 54 of the 57 eligible children participated. Results: Twenty five children had persistent nocturnal enuresis post-transplantation. Thirteen of them had previously attained reliable night-time dryness but developed secondary nocturnal enuresis following transplantation, with three subsequently regaining dryness at ages 8, 12, and 17 years; 10 were still wetting mean age 12.3. Twelve children had not achieved night-time dryness when transplanted (all were under 4 years of age at the time) and continued to wet. Only one of these children achieved dryness (at age 12 using oxybutynin); the other 11 remained wet at night at a mean age of 9.3 years. Twenty nine children were dry at night post-transplantation, but 21 of them had nocturia at least three times a week. There is a significant difference in age at transplantation between the primary nocturnal enuretic children (mean age 2.0) and the secondary nocturnal enuretic children (mean age 7.4) as well as between the primary nocturnal enuretic children and the non-enuretic children (mean age 9.0). Conclusions: Transplanting young children frequently delays the normal attainment of night-time continence or causes them to start wetting again. It should not be dismissed as a minor problem as it causes low self-esteem and is socially limiting. It is important families are aware it is a direct result of the transplantation process.     

Nocturnal enuresis is a common complication following cardiac transplantation.

AIMS: To investigate the incidence of nocturnal enuresis post-cardiac transplantation. METHODS: Seventy two cardiac transplantations have been performed in children under 16 years of age. All recipients who were alive and over 4 years of age at the time of the study received a questionnaire about urinary symptoms; 54 of the 57 eligible children participated. RESULTS: Twenty five children had persistent nocturnal enuresis post-transplantation. Thirteen of them had previously attained reliable night-time dryness but developed secondary nocturnal enuresis following transplantation, with three subsequently regaining dryness at ages 8, 12, and 17 years; 10 were still wetting mean age 12.3. Twelve children had not achieved night-time dryness when transplanted (all were under 4 years of age at the time) and continued to wet. Only one of these children achieved dryness (at age 12 using oxybutynin); the other 11 remained wet at night at a mean age of 9.3 years. Twenty nine children were dry at night post-transplantation, but 21 of them had nocturia at least three times a week. There is a significant difference in age at transplantation between the primary nocturnal enuretic children (mean age 2.0) and the secondary nocturnal enuretic children (mean age 7.4) as well as between the primary nocturnal enuretic children and the non-enuretic children (mean age 9.0). CONCLUSIONS: Transplanting young children frequently delays the normal attainment of night-time continence or causes them to start wetting again. It should not be dismissed as a minor problem as it causes low self-esteem and is socially limiting. It is important families are aware it is a direct result of the transplantation process.     

Measurement of fat digestion in early life using a stable isotope breath test.

13C breath tests are a safe, non-invasive way of assessing nutrient digestion and absorption that can be used repeatedly in infancy and childhood. The aim of this study was to assess their value for measuring fat digestion in infants and young children with cystic fibrosis, and healthy controls whose pancreatic exocrine function is immature, and to monitor pancreatic enzyme supplementation. Six infants with cystic fibrosis (aged 10-18 months) and nine healthy controls (aged 6-19 months) were studied. After an overnight fast each child ingested 7.5 mg/kg 13C trioctanoin (99 atom % excess) followed by a known volume of milk. Breath samples were collected before and at 30 minute intervals thereafter for five hours. The 13C enrichment of expired carbon dioxide was measured by gas isotope ratio mass spectrometry. The mean (SD) percentage dose recovery of 13C was 13.5 (5.3) for the cystic fibrosis group and 24.2 (6.7) for the healthy controls. When those with cystic fibrosis were studied after supplementary pancreatic enzymes, the mean percentage dose recovery rose to 17.1 (6.9). Total intraluminal lipolysis was diminished by 44% in young children with cystic fibrosis. Pancreatic enzyme supplements improved digestion by 27%. The 13C trioctanoin breath test was effective in detecting fat maldigestion and can be used to measure the benefits of enzyme supplements in early life.