Sleep Breathing Patterns Research Articles

Aerosol Therapy by Pressured Metered-Dose Inhaler-Spacer in Sleeping Young Children: To Do or Not to Do?

One third of young children are distressed during inhalation therapy. It has been suggested that administration during sleep could be a good alternative for these children. A laboratory study in our department using an infant upper airway model showed significantly higher lung doses from a pressured metered-dose inhaler (pMDI)-spacer for sleep-breathing patterns compared with wake-breathing patterns. We set up a daily life study to investigate the feasibility of aerosol administration by means of pMDI-spacer in sleeping young children. Over a period of 3 weeks, 30 children (age range, 6 to 23 months) with recurrent wheeze daily inhaled 1 puff of budesonide aerosol (200 mug) while awake and 1 puff during sleep. Filters positioned between the chamber and the facemask trapped the budesonide aerosol. Parents scored the child's asthma symptoms, degree of cooperation, and feasibility of administration on diary cards. In 69% of the sleep administrations, the children woke up, and in 75% of these cases the children were distressed. The mean filter dose (expressed as the percentage of the nominal dose) while awake was 47%, and during sleep it was 16% (p = 0.007). The median within-subject dose variability while awake was 50%, and during sleep it was 110% (p = 0.007). Aerosol administration by means of pMDI-spacer during sleep offers no advantage and is not a feasible treatment option in most young children.

Alterações cardiovasculares na síndrome da apnéia obstrutiva do sono

A síndrome da apnéia obstrutiva do sono (SAHOS) é uma condição prevalente na população, associada a maior risco cardiovascular, freqüentemente não-diagnosticada. O reconhecimento da síndrome requer alto grau de suspeita clínica, especialmente por cardiologistas, e pode ser confirmada por meio da polissonografia. O tratamento da síndrome com o uso de CPAP (pressão positiva na via aérea superior) é altamente eficaz, melhorando o padrão respiratório durante o sono, instituindo o sono reparador e, dessa forma, otimizando a qualidade de vida desses pacientes, além de atenuar ou reverter muitas das complicações cardiovasculares relacionadas a SAHOS. Este artigo aborda a fisiopatologia e os aspectos clínicos das comorbidades cardiovasculares associadas à síndrome.

Sleep breathing and periodic leg movement pattern in Angelman Syndrome: A polysomnographic study

Objective The aim of this study was to evaluate the sleep breathing patterns and to detect the eventual presence of periodic leg movements (PLMs) in patients affected by Angelman syndrome (AS). Methods Ten children with AS were recruited to participate in the study; the clinical diagnosis was confirmed by the genetic analysis (maternal 15q deletion, uniparental paternal disomy, or mutation of the UBE3A gene). All patients but two had presented epileptic seizures. Two age-matched groups of patients with mental retardation (MR) associated (MRE+) or not (MRE−) to epilepsy were used as control groups. All subjects underwent one polysomnographic recording, after one adaptation night. Sleep stages were scored according to standard criteria slightly modified in order to take into account the specific EEG patterns of AS, also the apnea/hypopnea index (AHI) was quantified; PLMs were identified and the PLM index (PLMI) was computed. The statistical analysis was carried out by means of the one-way ANOVA, followed by the Fisher LSD post-hoc test, when appropriate, and by means of the linear correlation coefficient between AHI and PLMI. Results Sleep macrostructure showed only few significant differences between children with AS and the other two groups of subjects: AS patients showed higher percentage of wakefulness after sleep onset and sleep onset latency; moreover, the percentage of REM sleep was reduced in AS and in MRE+ subjects. A tendency for AS subjects to present a higher PLMI than the other two groups was also found. AHI >5 was found in 30% of AS subjects, in 30.8% of MRE+, and only in 20% of MRE− patients ( χ 2=2.359, NS); 70% of AS patients, 38.5% of MRE+, and 46.7% of MRE− subjects had PLMI >5 ( χ 2=3.088, NS). Conclusions These results confirm our previous questionnaire-based findings of a high prevalence of sleep breathing disorder and important PLMs in AS and allow us to hypothesize that epilepsy, rather than mental retardation, might exacerbate these sleep disorders. Significance Sleep breathing disorder and PLMs might contribute to the cognitive impairment and to the worsening of life quality of subjects with AS and with MR (mostly those with epilepsy). Therefore, our findings suggest the need to explore these sleep disorders in children affected by MR and to set up a correct treatment.

Lens thickness and insulin dependent diabetes mellitus: a population based twin study.

To investigate the relation between lens thickness and duration of insulin dependent diabetes mellitus (IDDM). From the new population based Danish twin register, containing 20,888 twin pairs born between 1953 and 1982 (inclusive), all twin pairs having one or both partners affected with IDDM were searched. Among the 45 twin pairs available for clinical eye examination there were 15 monozygotic pairs, 14 dizygotic pairs of same sex, and 16 dizygotic pairs of opposite sex. Lens thickness was measured by ultrasonography. Using a twin control design, the relation between lens thickness and duration of IDDM was assessed by estimating the correlation between the intrapair difference in lens thickness and the intrapair difference in diabetes duration. In monozygotic twin pairs a statistically highly significant correlation between duration of diabetes and lens thickness was found (right eye: r = 0.88, p < 0.0001; left eye: r = 0.90, p < 0.0001). In dizygotic twin pairs of the same sex the correlations were r = 0.58 (p = 0.029) and r = 0.53 (p = 0.053) for right eye and left eye, respectively. For dizygotic twin pairs of opposite sex the correlations were r = 0.58 (p = 0.018) and r = 0.69 (p = 0.005) for right eye and left eye, respectively. The slope in regression analysis were similar for monozygotic twin pairs (0.025, common for both eyes) and dizygotic twin pairs grouped (0.024, common for both eyes). There is a statistically significant positive correlation between duration of IDDM and lens thickness, as assessed by the twin control method. The higher correlation in monozygotic twins compared with dizygotic twins suggests that genetic factors play an additional role in the determination of lens thickness. The similar slopes in regression analysis indicate that the effect of diabetes duration on lens thickness is independent of zygosity.

Breathing, sleep state, and rectal temperature oscillations.

Overheating may cause terminal apnoea and cot death. Rectal temperature and breathing patterns were examined in normal infants at home during the first 6 months of life. Twenty one infants had continuous overnight rectal temperature and breathing recordings for 429 nights (mean 20.4 nights, range 7-30) spaced over the first six months of life. Periods when breathing was 'regular' were directly marked on single night records. Sleep state was determined from respiratory variables. 'Regular' breathing was a reliable marker of 'quiet' sleep (specificity 93%). The duration of 'quiet' sleep increased from 6 to 22 minutes from two weeks to three months of age and then remained static, as did the proportion of sleep spent in the quiet phase (9% to 34%). Rectal temperature fell during 66% of quiet sleep and usually rose during rapid eye movement (REM) sleep. The drop in rectal temperature was maximal at the start of quiet sleep, whereas the maximum rise during REM sleep was reached after 10 to 15 minutes. Oscillations in rectal temperature are associated with changes in sleep and breathing state. The maturation of rectal temperature patterns during the first six months of life are closely related to a maturation of sleep state and breathing patterns.

1412 THE EFFECT OF CARDIAC DECELERATION ON OXYGENATION IN HEALTHY PRETERM INFANTS

In spite of the frequency with which acute deceleration in heart rate (HRD) occurs in the healthy preterm infant, its significance is poorly understood. We monitored R-to-R heart rate, impedance respiration, transcutaneous O2 (PtcO2) and CO2 (PtcCO2) and behavioral state for 3 hours in 13 healthy AGA infants between 32-35 weeks gestation at 7 days of age. Duration and peak drop were measured for all HRD below 100 bpm. Mean and lowest values for PtcO2 and PtcCO2 levels were determined during and for 10 seconds preceding and following the HRD. Sleep state and breathing pattern were identified for each. Nine infants had 1-7 HRD during the monitoring period. The mean drop from the base line was 48.6% with a range of 30-64. The mean duration was 22.35 seconds with a range of 8-66. The PtcCO2 decreased from a mean low of 61 mmHg before to 56 during tne episode with a partial recovery to 57 in the 10 seconds afterwards. PtcCO2 levels showed a small rise during the episodes. Blood gases remained within normal limits even in the most prolonged HRD. Drops occurred during wakefulness and sleep whether breathing was regular or periodic. Only one was associated with apnea > than 10 seconds and one third occurred with shorter pauses. Short breathing pauses with HRD appear benign. Criteria for identifying those outside normal limits with pathological consequences need to be developed. The cardiac decelerations studied here are normal in the healthy preterm infant, indicating intact parasympathetic nervous system reflexes.

1288 DIMINISHED METABOLIC RESPONSE OF PREMATURE INFANTS TO A THERMAL STRESS WHILE PERIODIC BREATHING DURING SLEEP

Periodic breathing (PB) occurs frequently in premature infants and may represent immaturity of central chemoreceptors. We postulate that other regulated functions such as temperature might be altered during episodes of PB. Six premature infants were studied under radiant warmers for 6-8 hours while simultaneous measurements of oxygen consumption (VO2), skin (Tabd) and core (Trec) temperature, EEG, EOG, EMG, and respiration were made. After periods of stabilization (Tabd=36.5 ± 0.5 and Trec=37.0 ± 0.2°C.), Tabd was allowed to fall slowly for short periods 4-10 times during the study period. For each of the 907 minutes of total sleep time (TST), breathing pattern (PB or non-PB), state, and VO2 were assessed. PB occurred in all but one subject and accounted for 11-60% of the TST. PB was distributed equally between REM and NREM sleep. The values for VO2 were then compared during sleep for warm and cool periods by breathing pattern. These data support our hypothesis and suggest that PB during sleep is associated with a decreased metabolic response to thermal stress.

Sleep Stages, Breathing Patterns and Arterial Blood Gas Tensions during Transient Hypoxaemia of Sleep in Chronic Bronchitis and Emphysema

Sleep Stages, Breathing Patterns and Arterial Blood Gas Tensions during Transient Hypoxaemia of Sleep in Chronic Bronchitis and Emphysema