Biomedical subjects

C Guilleminault

Publications and source records attributed to C Guilleminault.

At least 145 records · Page 8Linked to original sources

PubMed1996

Augmented very low frequency component of heart rate variability during obstructive sleep apnea.

After documenting the presence of obstructive sleep apnea syndrome (OSAS) through polysomnographic monitoring, we performed simultaneous ambulatory recordings of electrocardiogram, oronasal airflow, and pulse oximetry on 12 OSAS patients with normal autonomic nervous function for a period of 24 hours. The power spectrum of heart rate variability was investigated before and during treatments using dental appliances. Freuquency domain analysis showed that the very low frequency component of heart rate (0.008-0.04 Hz) was increased in OSAS patients and that a very low frequency peak appeared during episodes of obstructive sleep apnea. The increase in very low frequency identification was synchronized with episodes of absence of air exchange or hypoxemia (decreased arterial oxygen saturation) that occurred repeatedly at a cycle length of 25-120 seconds in our subjects. Frequency domain analysis of heart rate variability before and during prosthetic mandibular advancement treatment showed that only the very low frequency was significantly decreased during prosthetic mandibular advancement treatment, whereas the other frequencies, i.e. high, low, and ultralow frequency component values, showed no significant changes. Time domain analysis of heart rate variability before and during prosthetic mandibular advancement treatment showed no significant changes in any of these parameters. Frequency domain analysis of heart rate variability during nocturnal sleep, especially investigation of very low frequency and very low frequency peak, can be a noninvasive low-cost approach to diagnose and even better monitor subjects undergoing treatment at home, particularly considering that R-R intervals can be extracted from pulse oximetry and that analysis software programs are already commercially available.

Adult↗

PubMed1996

Blood pressure "dipping" and "non-dipping" in obstructive sleep apnea syndrome patients.

Obstructive sleep apnea syndrome (OSAS) has been associated with a higher than normal cardiovascular morbidity and mortality. Some OSAS patients lack the sleep-related, nocturnal decrease, or "dip," in blood pressure which is seen in normal individuals. These subjects, called "non-dippers," may be at greater risk for cardiovascular problems. We studied 40 OSAS patients (including 3 women) and 6 control subjects, all identified by polysomnography, for nocturnal blood pressure "dipping." We performed a second nocturnal polysomnogram to determine their apnea and hypopnea indices, (A + H)I, and oxygen saturation levels at the beginning of the study and then initiated 48 hours of ambulatory blood pressure monitoring, with data points collected every 30 minutes. Controls, which included one hypertensive subject, were all dippers. Nineteen OSAS subjects (48% of OSAS individuals) were systolic non-dippers and only 9 of them (22.5%) were diastolic non-dippers. We considered the following clinical variables as potential predictors of non-dipping: age, body mass index, respiratory disturbance index, years of reported loud snoring by bed partners, lowest oxygen saturation during nocturnal sleep, and percentage of sleep time spent with oxygen saturation below 90%. Multiple regression analyses indicated respiratory disturbance index as the only significant variable for systolic (p = 0.04) and diastolic (p = 0.03) blood pressure non-dipping. When we forced the following two nonsignificant variables into the model, they showed a very meager impact: number of years with reported loud snoring (p = 0.4 and p = 0.5, respectively for systolic and diastolic blood pressure non-dipping) and age (p = 0.5 and p = 0.6). The calculated model explained only a low percentage of the variance with an r2 of 0.25 and 0.26 for systolic and diastolic blood pressure non-dipping, respectively. Analysis of hypertension/normotension and dipping/non-dipping failed to show a significant relationship in the studied population. Fifty percent of the normotensive OSAS subjects were non-dippers and 43% of the hypertensive OSAS subjects were also non-dippers. We found a relationship between increasing respiratory disturbance index and increasing average 24-hour systolic blood pressure only when OSAS subjects were non-dippers and hypertensive.

Adult↗

PubMed1996

A laboratory validation study of the diagnostic mode of the Autoset system for sleep-related respiratory disorders.

We performed a validation study of the diagnostic mode of the Autoset system (ResMed, Australia) on a group of 44 snorers (10 women). We compared the result of the Autoset's automatic analysis of nasal airflow (using nasal prongs) to those of an in-laboratory polysomnographic study with a Fleisch facemask pneumotachograph. For the first 29 patients, the Autoset software was set to recognize only apneas; for the remaining 15, the software was modified to recognize both apneas and hypopneas. Relative to polysomnography, the Autoset overestimated the number of apneas. Oral breathing or displacement of the nasal prongs partially explained these differences. A significant correlation was found between the apnea indices (AI) assessed by the two methods (r = 0.98). For an AI of 20/hour the Autoset was 100% sensitive and 88% specific. The Autoset significantly underestimated the number of hypopneas compared to the polysomnograph with pneumotachograph (62.9 +/- 4.7 vs. 85.5 +/- 73.1, P = 0.04), although for an apnea-hypopnea index of 20, Autoset was 100% sensitive and 88% specific. The lack of linearity of Autoset's volume evaluation at low volumes could explain most of the differences. Our results indicate that the Autoset system, in its diagnostic mode, is a useful tool for identifying patients with significant obstructive sleep apnea syndrome. The system is less useful in patients with mild to moderate sleep disordered breathing, where it may give erroneous results.

Adult↗

PubMed1996

A reversible uvulopalatal flap for snoring and sleep apnea syndrome.

Velopharyngeal incompetence (VPI) is a recognized complication of uvulopalatopharyngoplasty (UPPP) for obstructive sleep apnea. A new uvulopalatal flap (UPF) technique that modifies the UPPP and reduces this risk is presented. The technique achieves the same anatomic results as the UPPP but is reversible. To evaluate clinical outcomes of this new procedure, selected variables were compared in patients who underwent UPPP and UPF procedures. Eighty patients were examined (59/80 UPF, 21/80 UPPP) in a prospective and consecutive manner. Subjects underwent polysomnography and extensive airway evaluations. The characteristics of all patients, at baseline, were evaluated. The study variables included age, sex, body mass index (BMI), palatal length (PNS P) in millimeters, respiratory disturbance index (RDI), lowest oxygen saturation during sleep and a subjective snoring scale. Sixty-seven of the 80 patients underwent simultaneous hypopharyngeal surgery. Data were analyzed with a SAS program. No statistical difference existed between groups. The postoperative character of the palate and the change in snoring scores were the same in all patients (p = 0.584). A positive correlation existed between improvement in the snoring score and the amount of tissue removed or repositioned in the patients treated with UPF (correlation coefficient = 0.370, p = 0.004). In contrast, there was a negative correlation in the UPPP group for the same parameters (correlation coefficient = -0.195, P = 0.409). This suggests there was a difference between these two groups despite the fact that the baseline and postoperative lengths, as well as tissue removed or repositioned, were equivalent. This further suggests that the UPF may reduce snoring to a greater extent than the UPPP. No significant complications were seen in either group. There was no evidence of VPI, even in the early postoperative period. The new reported procedure is reversible and conservative and reduces the risk of VPI. Snoring is improved, which is consistent with a decrease in airway resistance or obstruction.

Adult↗

PubMed1996

Tiredness and somnolence despite initial treatment of obstructive sleep apnea syndrome (what to do when an OSAS patient stays hypersomnolent despite treatment).

From a database of 4,129 patients with sleep-disordered breathing (SDB), we found 207 subjects (43 women) that still complained of daytime tiredness, fatigue, and/or sleepiness despite treatment. In 25 subjects the sleepiness developed 1 to 36 months following treatment and was related to noncompliance (8 subjects), significant weight increase and/or inappropriate treatment (10 subjects), or development of new medical problems (7 subjects). In the remaining 182 subjects, sleepiness was noted within 1 month after what was judged appropriate treatment for SDB. In this group, the reason for persistent complaint was divided into four categories: 1) inappropriate treatment as a result of not using the measurement of esophageal pressure (Pes) in the initial diagnosis (41 subjects), 2) nonfunctional treatment (3 subjects), 3) associated narcolepsy-like syndrome (2 subjects), and 4) emergence of obesity and/or periodic leg movements as significant factors (135 subjects). The 135 subjects in this last category could be subdivided into three subgroups: 1) younger subjects, severely overweight with lower mean nocturnal saturated arterial oxygen (SaO2) values; 2) older subjects, of normal weight, with high numbers of periodic leg movements (PLM); and 3) moderately overweight subjects, with a combination of PLM and lower mean SaO2 values than expected. Treatments were aimed at eliminating the identified problems; they included standard medications for PLM and nasal bilevel positive airway pressure (BiPAP) for low SaO2 measurements. These treatments were not effective in specific cases, and stimulant medications had to be prescribed.

Adult↗

PubMed1996

Sleep-disordered breathing and systemic hypertension in the older male.

OBJECTIVE: To investigate the relationship between sleep-disordered breathing (SDB) and essential hypertension in a population of older male hypertensives. PATIENTS: One-hundred forty consecutive older hypertensive males. MEASUREMENTS: Monitoring of sleep-related breathing abnormality with a portable sleep apnea monitor (level III device). Assessment of complaints related to sleep quality using a validated questionnaire. Systemic arterial blood pressure according to WHO standards and biochemical analyses. SDB was defined as more than 10 abnormal respiratory events per hour of sleep. DESIGN: Prospective investigation on a retrospective cohort. SETTING: Veterans Administrations hypertension clinic. MAIN RESULTS: SDB was diagnosed in 80% of this older, hypertensive, male population. Thirty-four percent of all study subjects presented with severe SDB, with more than 30 abnormal respiratory events per hour of sleep. Subjects with SDB were significantly heavier (BMI = 30.0 +/- 5.2 kg/m2) than subjects without SDB (BMI = 26.8 +/- 5.1 kg/m2, P = .004). Furthermore, subjects with SDB slept significantly longer (by a mean of 46 minutes/night, P = .027) and complained significantly more often of daytime sleepiness than subjects without SDB (P = .018). Fifty percent of all 140 subjects snored more than 10% of the total sleep time, and 26% snored for more than one-third of the night. No significant differences in blood pressure values were observed in subjects with compared with subjects without sleep-disordered breathing. However, a considerable number of subjects presenting with hypertensive blood pressure values despite treatment could be identified. Subjects presenting with hypertensive blood pressure values had a significantly higher severity index of SDB than subjects with normotensive blood pressure values (P = .047). CONCLUSIONS: This investigation supports data showing that undiagnosed SDB is a common phenomenon in older male individuals, leading to impaired daytime functioning and impairment of overall quality of life. More importantly, our data suggests that untreated SDB may have an adverse effect on the efficacy of antihypertensive treatment in hypertensive individuals with sleep-disordered breathing.

Aged↗

PubMed1996

Insulin resistance and sleep-disordered breathing in healthy humans.

Fifty healthy, normotensive individuals (34 women) with a mean age of 44.3 +/- 13.2 yr and a mean body mass index of 27.1 +/- 5.4 kg/m2 were tested for the presence or absence of insulin resistance and sleep-disordered breathing. The hypothesis of this investigation was that insulin resistance is associated with sleep-disordered breathing. In vivo insulin action with determination of steady-state plasma glucose (SSPG) and insulin was measured using simultaneous intravenous infusion of somatostatin, glucose, and insulin via a Harvard pump. Determination of sleep-disordered breathing was performed through clinical assessment and portable nocturnal monitoring using a validated sleep apnea recorder. Individuals with > or = 10 hypoxic respiratory events per hour of sleep were significantly more insulin-resistant than subjects without sleep-breathing disorders. After adjusting the relationship between insulin resistance and sleep-disordered breathing for potential confounding variables, it was found that this relationship was entirely dependent on body mass.

Adult↗

PubMed1996

Objective patient compliance in long-term use of nCPAP.

Concerns remain regarding patient compliance with nasal continuous positive airway pressure (nCPAP). Poor objective compliance during the first months of treatment has been reported, but no data are available among chronically treated patients. Use of nCPAP, in 17 chronically treated obstructive sleep apnoea patients (820+/-262 days) was evaluated objectively using a pressure monitor (MC+; Sefam, France). Two consecutive recording periods of 30 sessions of treatment were scheduled at the patient's home. To minimize the potential bias caused by the introduction of the monitor, only the pressure data obtained at the end of the second period of recording (T2) were analysed. During the 28.1+/-2.6 monitored days, the mean effective daily rate of use was 7.1+/-1.1 h, 97% of the rate indicated by the standard in-built time counter. The prescribed pressure was observed during 95% of the machine run time. The nCPAP system was used for 94% of the monitored days. Sixty percent of the patients used their device every day. These preliminary results suggest that, contrary to reported compliance during the early period of the treatment, objective use of nasal continuous positive airway pressure therapy in chronically treated patients is satisfactory.

Female↗

PubMed1996

Hypnagogic and hypnopompic hallucinations: pathological phenomena?

BACKGROUND: Hypnagogic and hypnopompic hallucinations are common in narcolepsy. However, the prevalence of these phenomena in the general population is uncertain. METHOD: A representative community sample of 4972 people in the UK, aged 15-100, was interviewed by telephone (79.6% of those contacted). Interviews were performed by lay interviewers using a computerised system that guided the interviewer through the interview process. RESULTS: Thirty-seven per cent of the sample reported experiencing hypnagogic hallucinations and 12.5% reported hypnopompic hallucinations. Both types of hallucinations were significantly more common among subjects with symptoms of insomnia, excessive daytime sleepiness or mental disorders. According to this study, the prevalence of narcolepsy in the UK is 0.04%. CONCLUSIONS: Hypnagogic and hypnopompic hallucinations were much more common than expected, with a prevalence that far exceeds that which can be explained by the association with narcolepsy. Hypnopompic hallucinations may be a better indicator of narcolepsy than hypnagogic hallucinations in subjects reporting excessive daytime sleepiness.

Adolescent↗

PubMed1996

Sleep and neuromuscular disease: frequency of sleep-disordered breathing in a neuromuscular disease clinic population.

We investigated 60 adult and pediatric patients (33 male, 27 female) with various neuromuscular disorders for sleep-disordered breathing in a clinic population at a local altitude of 1,500 m. Measurements included a questionnaire concerning symptoms of sleep and daytime function, a disability index, and pulmonary function tests. We used an EdenTrace monitor for 1 night to evaluate breathing during sleep and calculated mean and minimum oxygen saturation (SpO2), total apneas, hypopneas, and respiratory disturbance index (RDI). We had validated the EdenTrace II monitor prior to the study. The majority of the patients had symptoms of daytime dysfunction. The frequency of sleep-disordered breathing in this population was much higher (42% with RDI > 15) than frequencies indicated in recent population-based surveys. Spirometry revealed no positional effect in this population. Statistical analysis comparing RDI with disability index, pulmonary function tests, age, sex, body mass index, and Epworth Sleepiness Scales identified no strong correlates that could be used as predictors of sleep-disordered breathing in this population. Sleep studies using ambulatory equipment such as the EdenTrace II are an easy and effective means of identifying sleep-disordered breathing in patients with neuromuscular disorders and, given the high frequency of sleep-disordered breathing in our sample, should be performed on most patients with neuromuscular disorders if sleep-disordered breathing is to be identified early.

Adolescent↗

PubMed1996

Sleep fragmentation as a risk factor for hypertension in middle-aged nonapneic snorers.

Although a high prevalence of hypertension has been observed in snorers, whether there is a direct link between hypertension and snoring remains controversial. It has recently been demonstrated that an abnormal amount of breathing effort during snoring is responsible for sleep fragmentation even in the absence of sleep apnea syndrome criteria. We hypothesized that sleep fragmentation during snoring may be a direct risk factor for the development of hypertension. On the basis of polysomnographic data, 105 nonapneic patients between 40 and 65 years of age referred for snoring with social impairment were selected and categorized as snorers with (n=55) or without sleep fragmentation (n=50) based on whether the arousals index was 10 or greater or less than 10/h of sleep, respectively. Sleep distribution did not differ between the two groups, except for a longer duration of wake after sleep onset (58 +/- 43 min vs 42 +/- 38 min) and a shorter duration of slow-wave sleep in the group with sleep fragmentation (72 +/- 34 min vs 97 +/- 34 min). Although there were no statistically significant differences between the snorers with and without sleep disruption in terms of age (51.3 +/- 7.7 vs 48.6 +/- 6.0 years), body mass index (26.9 +/- 4.0 vs 27.2 +/- 5.5 kg/m2), sex ratio, respiratory indexes during sleep, daytime sleepiness, and daytime tiredness, prevalence of systemic hypertension was significantly higher in the sleep-fragmented group (20/55 vs 7/50). This significant difference persisted (16/51 vs 6/49) when patients using antihypertensive drugs with possible effects on the CNS were excluded. Our data suggest that sleep fragmentation is common in patients who seek medical help for snoring with social impairment and may play a role in the development of hypertension.

Adrenergic beta-Antagonists↗

PubMed1996

Upper airway resistance syndrome, nocturnal blood pressure monitoring, and borderline hypertension.

Upper airway resistance syndrome (UARS) is a sleep-disordered breathing syndrome characterized by complaints of daytime fatigue and/or sleepiness, increased upper airway resistance during sleep, frequent transient arousals, and no significant hypoxemia. Of a population of 110 subjects (58 men) diagnosed as having UARS, we investigated acute systolic and diastolic BP changes seen during sleep in two different samples. First, six patients from the original subject pool were found to have untreated chronic borderline high BP, and were subjected to 48 h of continuous ambulatory BP monitoring before treatment and another 48 h of BP monitoring 1 month after the start of nasal-continuous positive airway pressure (N-CPAP) treatment. Five of six subjects used their equipment on a regular basis and had their chronic borderline high BP completely controlled. No change in BP values was seen in the last subject, who discontinued N-CPAP after 3 days. A second protocol investigated seven normotensive subjects drawn from the initial subject pool. Continuous radial artery BP recording was performed during nocturnal sleep with simultaneous polygraphic recording of sleep/wake variables and respiration. BP changes were studied during periods of increased respiratory efforts and at the time of alpha EEG arousals. Increases in systolic and diastolic BP were noted during the breaths with the greatest inspiratory efforts without significant hypoxemia. A further increase in BP was noted in association with arousals. Three of these subjects also underwent echocardiography during sleep, which demonstrated a leftward shift of the interventricular septum with pulsus paradoxus in association with peak end-inspiratory esophageal pressure more negative than -35 cm H2O. Our study indicates that, in the absence of classic apneas, hypopneas, and repetitive significant drops in oxygen saturation (below 90%), repetitive increases in BP can occur as a result of increased airway resistance during sleep. It also shows that, in some patients with both UARS and borderline high BP, high BP can be controlled with treatment of UARS. We conclude that abnormal upper airway resistance during sleep, often associated with snoring, can play a role in the development of hypertension.

Adult↗

PubMed1996

The effect of triazolam and flunitrazepam--two benzodiazepines with different half-lives--on breathing during sleep.

We performed a double-blind single-dose placebo/hypnotics crossover study randomized within groups to test the potential problems that a group of normal subjects, including subjects who snore, may face using hypnotic medications. Two benzodiazepine hypnotics--triazolam, 0.25 mg, and flunitrazepam, 2 mg tablets--were considered. Subjects were monitored with nocturnal polysomnography, including esophageal pressure (Pes) monitoring as a measure of respiratory efforts, and were given daytime performance tests. Results were analyzed for the total nocturnal sleep period and also by thirds of the night in consideration of the different half-lives of the studied drugs. Three specific respiratory variables were evaluated: mean breathing frequency for selected unit of time, "Delta Pes" (esophageal pressure at peak end-expiration minus Pes at peak end-inspiration) expressed in cm H2O, and the ratio of Delta Pes/Delta TI (inspiratory time), taken as an index of respiratory drive calculated for each respiratory cycle. There was no significant increase in either the respiratory disturbance index or the oxygen desaturation index (number of drops in arterial oxygen saturation of 4% or more per hour of sleep, as measured by pulse oximetry). There was a significant increase in mean breathing frequency with flunitrazepam compared with placebo, as well as a significantly larger percentage of time during sleep with Delta Pes above 10 cm H2O (taken as a cutoff point for normal respiratory effort) with both triazolam and flunitrazepam compared with placebo. These respiratory changes, even if significant, were minor but may become a liability in association with specific abnormalities.

Adult↗

PubMed1996

Adult psychophysiologic insomnia and positive history of childhood insomnia.

Sixty-five adults diagnosed with "psychophysiologic chronic insomnia" following the criteria of the Association of Sleep Disorders Centers were investigated. They were subdivided into two groups based on whether onset of the insomnia had occurred in childhood or adulthood. Fifty similar-aged patients with obstructive sleep apnea syndrome (OSAS) were also investigated and served as a contrast group. All subjects were given polygraphic recordings and structured interviews, and all completed sleep questionnaires after reviewing the questions with an investigator. On many indices evaluating subjective daytime alertness and well-being, the psychophysiologic insomnia patients had scores similar to the OSAS patients. There were no significant differences between the childhood-onset and adult-onset psychophysiologic insomnia patients on most of the investigated items. However, the childhood-onset psychophysiologic insomniinacs had moderately but significantly higher reports of nightmares. This group also reported having had longer sleep latencies, significantly more "fear of the dark" and more frequent nightmares during childhood than the adult-onset group. These statistically significant findings reflected only a moderate increase in subjective scores, however, and in general the childhood-onset and adult-onset psychophysiologic insomnia patients were very similar.

Adult↗

PubMed1996

EEG frequency changes during sleep apneas.

To study the effect of transient, apnea-induced hypoxemia on electrocortical activity, five patients with severe obstructive sleep apnea syndrome (OSAS) were investigated during nocturnal sleep. Polysomnographic and simultaneous digitized electro encephalographic (EEG) recordings for topographic and compressed spectral array analysis were made. The EEG recordings were timed exactly to respiratory events. During nonrapid eye movement (NREM) apnea, delta band amplitude increased, starting on average 13 seconds after the apnea onset. Average differences were 268% between initial and maximal values and 202% between initial and final values. In contrast, significant increases in delta amplitudes between the onset and end of REM apneas did not occur, although some caused deep oxygen desaturations. Changes in delta activity were not correlated to NREM apnea duration or degree of desaturation. These results indicate that the increased delta activity during NREM apneas may not be caused by arterial hypoxemia. It could instead be due to either an arousal mechanism, since arousals may be preceded by slow waves in EEG, or to a breakthrough of slow-wave-sleep activity. The sleep disturbance in severe OSAS may create such a propensity for slow-wave sleep that stages pass much more rapidly than in normal persons.

Adult↗

PubMed1996

Rapid shift in sleep time and acrophase of melatonin secretion in short shift work schedule.

Tolerance to shift work and adaptability to shifting schedules is an issue of growing importance in industrialized society. We studied 40 registered nurses, 20 on fixed day-shifts and 20 on fixed night-shifts, to assess whether workers with rapidly shifting schedules were able to adapt their melatonin secretion and sleep-wake cycles. The day-shift worked 5 days with 2 days off and the night-shift worked 3 nights with 2 off. All night-shift personnel acknowledged shifting back to daytime schedules on their days off. Sleep-wake was determined by sleep logs and actigraphy. To measure 6-sulfatoxymelatonin levels, urine was collected at 2-hour intervals on the last work day and on the last day off. Night-shift workers slept significantly more on days off. Napping on the job occurred in 9/20 night-shift workers (mean 114 minutes) between 3 and 6 a.m. The acrophase of 6-sulfatoxymelatonin in day-shift nurses occurred at similar times on workdays and off days. In night-shift nurses, the acrophase was about 7 a.m. on days off, but had a random distribution on workdays. Further analysis revealed two subgroups of night-shift nurses: six subjects (group A).demonstrated a rapid shift in melatonin secretion (acrophase at near 12 noon on work days and at near 7 a.m. on days off) while 14 nurses (group B) did not shift. Group A nurses slept more in the daytime on work days and their total sleep time was the same as day-shift nurses. Group A was slightly younger and was composed solely of women (there were nine women and five men in group B). Age may be a factor in the ability to adapt to rapidly shifting schedules.

Adult↗

PubMed1996

Recognition of sleep-disordered breathing in children.

OBJECTIVE: To determine whether upper airway resistance syndrome (UARS) can be recognized and distinguished from obstructive sleep apnea syndrome (OSAS) in prepubertal children based on clinical evaluations, and, in a subgroup of the population, to compare the efficacy of esophageal pressure (Pes) monitoring to that of transcutaneous carbon dioxide pressure (tcPCO2) and expired carbon dioxide (CO2) measurements in identifying UARS in children. STUDY DESIGN: A retrospective study was performed on children, 12 years and younger, seen at our clinic since 1985. Children with diagnoses of sleep-disordered breathing were drawn from our database and sorted by age and initial symptoms. Clinical findings, based on interviews and questionnaires, an orocraniofacial scale, and nocturnal polygraphic recordings were tabulated and compared. If the results of the first polygraphic recording were inconclusive, a second night's recording was performed with the addition of Pes monitoring. In addition, simultaneous measurements of tcPCO2 and endtidal CO2 with sampling through a catheter were performed on this second night in 76 children. These 76 recordings were used as our gold standard, because they were the most comprehensive. For this group, 1848 apneic events and 7040 abnormal respiratory events were identified based on airflow, thoracoabdominal effort, and Pes recordings. We then analyzed the simultaneously measured tcPCO2 and expired CO2 levels to ascertain their ability to identify these same events. RESULTS: The first night of polygraphic recording was inconclusive enough to warrant a second recording in 316 of 411 children. Children were identified as having either UARS (n = 259), OSAS (n = 83), or other sleep disorders (n = 69). Children with small triangular chins, retroposition of the mandible, steep mandibular plane, high hard palate, long oval-shaped face, or long soft palate were highly likely to have sleep-disordered breathing of some type. If large tonsils were associated with these features, OSAS was much more frequently noted than UARS. In the 76 gold standard children, Pes, tcPCO2, and expired CO2 measurements were in agreement for 1512 of the 1848 apneas and hypopneas that were analyzed. Of the 7040 upper airway resistance events, only 2314 events were consonant in all three measures. tcPCO2 identified only 33% of the increased respiratory events identified by Pes; expired CO2 identified only 53% of the same events. CONCLUSIONS: UARS is a subtle form of sleep-disordered breathing that leads to significant clinical symptoms and day and nighttime disturbances. When clinical symptoms suggest abnormal breathing during sleep but obstructive sleep apneas are not found, physicians may, mistakenly, assume an absence of breathing-related sleep problems. Symptoms and orocraniofacial information were not useful in distinguishing UARS from OSAS but were useful in distinguishing sleep-disordered breathing (UARS and OSAS) from other sleep disorders. The analysis of esophageal pressure patterns during sleep was the most revealing of the three techniques used for recognizing abnormal breathing patterns during sleep.

Airway Resistance↗

PubMed1996

Should everyone be monitored for upper-airway resistance and how?

Preliminary data indicate that the use of a morphometric model, an expert system with standardized questions, and an evaluation of snoring can be effective tools for diagnosing upper-airway sleep-disordered breathing (UASDB) in many cases. This eliminates the need for many sleep recordings.

Airway Obstruction↗