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The aims of this study were to assess the cut-off values for oxygen desaturation index ≥ 3% (ODI3) to confirm obstructive sleep apnea (OSA) in subjects undergoing polysomnography (PSG) and home-based respiratory polygraphy (RP), and to propose an algorithm based on pulse oximetry (PO) for initial management of patients with suspected OSA.This was an observational, cross-sectional, retrospective study. ODI3 was used to classify subjects as healthy (no OSA = AHI 5 or 15 events/h) or unhealthy (OSA = AHI ≥ 5 or ≥ 15 events/h). On the PSG or experimental group (Exp-G), we determined ODI3 cut-off values with 100% specificity (Sp) for both OSA definitions. ODI3 values without false positives in the Exp-G were applied to a validation group (Val-G) to assess their performance. A strategy based on PO was proposed in patients with suspected OSA.In Exp-G (PSG) 1141 patients and in Val-G (RP) 1141 patients were included. In Exp-G, ODI3 12 (OSA = AHI ≥ 5) had a sensitivity of 69.5% (CI95% 66.1-72.7) and Sp of 100% (CI95% 99-100), while an ODI3 ≥ 26 had a 53.8% sensitivity (CI95% 49.3-58.2) and Sp of 100% (CI95% 99.4-100) for AHI ≥ 15. A high pretest probability for OSA by Berlin questionaire (≥ 2 categories) had a lower diagnostic performance than by STOP-BANG questionnaire ≥ 5 points (AHI ≥ 5: 0.856 vs. 0.899, p 0.001; AHI ≥ 15: 0.783 vs. 0.807, p 0.026).We propose the initial use of PO at home in cases of moderate-to-high pretest probability of OSA. This algorithm considers PO as well as RP and PSG for more challenging cases or in case of doubt.

Objective To compare pulse oximetry with manual analysis against all signals of respiratory polygraphy. Material and Methods This retrospective study estimated sensitivity (S), specificity (Sp) and positive/negative likelihood ratio (LR+/-) of the oxygen desaturation index (ODI-test) and apnea-hypopnea index (AHI-reference). Results 3854 patients (61.5% men) were included. Age, BMI, Epworth sleepiness scale and AHI were: 55 years (44-65), 30.9kg/m2 (27-36), 7 points (4-11), and 14 events/hour (6-25), respectively. 18% showed an AHI 15 and < 30, and 31% > 30. The S, Sp, and LR+/- of ODI for AHI = 5 events/hour was 93%, 92%, 12 and 0.08 with an accuracy of 93%. For AHI = 15 events/hour, the values were: S 94%, Sp 94%, LR+ 15 and LR- 0.06 and 94% accuracy (r(2) Spearman: 0.92). Conclusion In a population at a high risk for OSA, home-based pulse oximetry had a diagnostic accuracy > 90% when is compared against all respiratory signals obtained from simplified home sleep testing.

To assess the relationship between hypoxemia during polysomnography (PSG) and patient-reported night sweats (NS).This retrospective observational study included adult patients who completed a standardized sleep questionnaire and the Epworth Sleepiness Scale (ESS) before PSG.We included 1397 patients (41% women). The median age was 52 years, 80% had obstructive sleep apnea (OSA) defined as an apnea-hypopnea index (AHI) ≥ 5, and 35% were obese. A total of 245 patients (17.5%) reported NS. Their prevalence was higher among patients with OSA compared to controls (18.9% vs. 12.2%, p 0.01). In the bivariate analysis, the variables associated with NS were BMI, AHI, hypoxemia (T90 ≥ 2.5% of total recording time plus minimum SOIn patients with OSA, night sweats were significantly and independently associated with a higher hypoxic burden.

The objective of the study was to develop a multiparametric oximetry indicator (IMp-SpO2) to diagnose obstructive sleep apnea in adults. This was an observational, retrospective study of diagnostic accuracy. We included adults who had had a diagnostic polysomnography with few artifacts and a total sleep time of at least 180 min in the sleep laboratory. Obstructive sleep apnea (OSA) was defined as an apnea-hypopnea index (AHI) ≥ 5. The database was randomly divided into an experimental (Exp-G) and validation (Val-G) group. The program calculated several parameters of oxygen saturation variability (Par-VarSpO2): (a) oxygen desaturation index (ODI ≥ 3, 4%) and (b) 90, 95, and 97.5 percentiles of both the number of oxygen desaturations ≥ 3 and 4% (P90–97.5 OD3/4 W5-60) and SpO2 standard deviations in moving windows from 5 to 60 min (P90–P97.5 SDSpO2 W5-10). Area under the ROC curve (AUC-ROC), sensitivity, specificity, positive/negative likelihood ratios, and accuracy were calculated. Of 1141 adults included in the study, experimental (571) and validation group (570) were similar (women 47% vs 45%, BMI 27.5 kg/m2 vs 27.2 kg/m2, and AHI 11.7 vs 12, p NS). The IMp-SpO2 developed in the experimental group consisted of a combination of 10 parameters of oxygen saturation variability. The presence of at least one IMp-SpO2 variable had a high diagnostic performance for OSA (sensitivity/specificity/accuracy: Exp-G: 92.8/94/93.2%; Val-G: 93/95.2/93.7%). The IMp-SpO2 AUC-ROC was higher (Exp-G 0.934, Val-G 0.941) than most of the Par-VarSpO2 (0.898–0.929, p 90% accuracy for OSA diagnosis in adults.

Background and Objective: The usefulness of pulse oximetry for the management of obstructive sleep apnea is controversial. The aim of this study was to assess the accuracy for indication of Continuous Positive Airway Pressure (CPAP) treatment in patients with suspected obstructive sleep apnea (OSA) based on clinical and oximetry data as compared to polysomnography (PSG). Methods: This multicenter observational study involved seven sleep laboratories. Patients with suspicion of OSA who completed a standardized sleep questionnaire and a diagnostic PSG were enrolled. Eight observers logged on to a website independently and blindly. Seven observers only accessed the clinical data, curve and pulse oximetry results (Os-SO2-test method), while the eighth observer had full access to all indicators of PSG (O-PSG-reference method). Once observers assessed the information available on the website, they had to choose between three CPAP treatment options (yes/no/do not know) based on their knowledge and criteria. Results: 411 subjects (228 men), median age 54 years, were available for evaluation. Os-SO2 had lower sensitivity (S), greater specificity (Sp) and positive likelihood ratio (PLR) to prescribe CPAP in patients more symptomatic (Epworth Sleepiness Scale-ESS > 10 or comorbidities) than those with fewer symptoms (ESS < 11 without comorbidities) (S 45-75% versus 45-91%, p 0.028); Sp 93.8-100% versus 68.5-96.6%, p 0.004; PLR > 10 versus 2.9-17, p

To evaluate the performance of clinical criteria (CC) for diagnosis and initiation of empirical treatment with continuous positive airway pressure (CPAP) in patients with suspected obstructive sleep apnea (OSA) compared with the treatment decision based on sleep studies (polysomnography or respiratory polygraphy), guidelines, and experience of participating physicians. This was a simulated intention-to-treat study in a retrospective (G1) and prospective (G2) cohort. Four observers (two per group) called CC1 and CC2 reviewed the sleep questionnaires and indicated CPAP if the patients presented snoring, frequent apneas (≥ 3–4/week), body mass index (BMI) > 25 kg/m2, sleepiness (Epworth > 11), or tiredness (at least 3–4 times per week) and some comorbidity (hypertension, coronary/cerebrovascular event, diabetes). Ten independent observers formed two groups of five (FD1 and FD2) and were blinded to each other’s opinion. These observers in FD1 and FD2 decided CPAP treatment based on guidelines of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) or guidelines of the American Academy of Sleep Medicine (AASM) and factored in their own opinion. Sensitivity (S), specificity (Sp), and positive/negative likelihood ratios (LR+/−) were calculated with the test method: CC1/2, and the reference method: majority decision of FD1/2. A total of 653 patients (264 women, 40%) were studied. Median age was 54 years, BMI 28 kg/m2, and apnea hypopnea index (AHI) 16.5 events/h. S ranged from 21 to 25% (p 0.60), Sp 96.1 to 97.6% (p 0.39), and LR+ of clinical criteria 6.4 to 8.9 (p 0.52). CPAP indication without a previous sleep study showed a low sensitivity (≅ 22%) but a specificity greater than 95% in patients with high pretest probability for OSA (snoring, report of frequent apneas, BMI > 25 kg/m2 and sleepiness or tiredness plus comorbidity).

Purpose: Obstructive Sleep Apnea-Hypopnea Syndrome (OSAS) is a public health problem. We designed a pilot study to validate empiric indication of CPAP therapy in a population with moderate- to-high pre-test probabilities who underwent self-administered home-based respiratory polygraphy (RP). Methods: A cross-sectional simulation study was performed. CPAP therapy could be indicated by two independent blind observers. Observer 1´s decision was based on the results of STOP-BANG (SBQ) and Epworth Sleepiness Scale (ESS) and Observer 2 used all objective data provided by RP + SBQ + ESS. Results: We evaluated 1763 patients; 1060 men and 703 women (39.2%) with a mean age of 53.6±13.8 and a body mass index (BMI) of 32.8±7.5 kg/m2. We found evidence of mild (34.1%), moderate (26.6%), and severe (18.3%) There were Apnea-Hypopnea Index (AHI) relationship between > 5 or < 5 SBQ and RP AHI (p 25 kg/m2 + snoring (S) + observed apnea (O) + 1 of the following: ESS > 11, hypertension (HT) or > 5 SBQ components showed sensitivity of 40% (CI95%: 37.3-43) and specificity of 95.1% (CI93.4-96.4). The performance of 5 SBQ components with regard to gender and empirical CPAP therapy was; (women vs. men): AUC-ROC 0.625 (CI95%: 0.599-0.651) vs. 0.70 (CI95%: 0.68-0.72), p

Introduction: The most effective treatment for moderate to severe obstructive sleep apnea (OSA) is continuous positive airway pressure (CPAP) but adherence may be a limiting factor. Most compliance studies often only include patients under CPAP treatment, neglecting the importance of access to treatment. The aim of this study was to evaluate CPAP access and compliance in OSA patients, after CPAP indication and titration. Methods: We included moderate to severe OSA patients, diagnosed by in-lab polysomnography (PSG), with CPAP indication and effective pressure titration. Between 12 to 18 months after treatment was indicated a telephone questionnaire was administered including questions about access to CPAP, reasons of no access, reported adherence and symptoms improvement. Results: A total of 213 patients responded to the survey (171 males, mean age 53.4±13.5 and BMI 34.02±8.8 kg/m2). Almost a third of the patients (28.2%) did not initiate CPAP treatment. Out of 213, 153 patients (71.8%) started treatment with CPAP and 120 (56.3%) reported still being under treatment a year after indication, additionally, 85.8% reported that they were using it =4hs/night. Those who accessed to CPAP were on average, older age, had full coverage of treatment by their medical insurance, required lower effective pressure and experienced more severe sleepiness compared to those individuals who did not accessed to CPAP. Discussion: A significant proportion of OSA patients with CPAP indication did not initiate and/or eventually abandoned CPAP. Approximately only 50% of the patients were still under treatment, with acceptable selfreported adherence rate and clinical response, one year after the initial treatment indication. Additional measures are necessary to increase access to CPAP and improve long-term compliance.

Objective. According to current guidelines, autoscoring of respiratory events in respiratory polygraphy requires manual scoring. The aim of this study was to evaluate the agreement between automatic analysis and manual scoring to identify patients with suspected OSA.Methods. This retrospective study analyzed 791 records from respiratory polygraphy (RP) performed at home. The association grade between automatic scoring and manual scoring was evaluated using Kappa coefficient and the agreement using Bland and Altman test and intraclass correlation coefficient (CCI). To determine the accuracy in the identification ofAHI≥30 eV/h, the ROC curve analysis was used.Results. The population analyzed consisted of 493 male (62.3%) and 298 female patients, with an average age of54.7±14.20years and BMI of32.7±8.21 kg/m2. There was no significant difference between automatic and manual apnea/hypopnea indexes (aAHI, mAHI): aAHI 17.25 (SD: 17.42) versus mAHI21.20±7.96(p; NS). The agreement between mAHI and aAHI toAHI≥30was 94%, with a Kappa coefficient of 0.83 (p<0.001) and a CCI of 0.83. The AUC-ROC, sensitivity, and specificity were 0.99 (CI 95%: 0.98-0.99,p<0.001), 86% (CI 95%: 78.7–91.4), and 97% (CI 95%: 96–98.3), respectively.Conclusions. We observed good agreement between automatic scoring and sequential manual scoring to identify subjects withAHI≥30 eV/h.

It has been reported that the clinical expression of obstructive sleep apnea (OSA) may differ in women and men. The objective of this study was to evaluate the influence of gender on reported OSA-related symptoms in a large clinical population of patients. The database from the sleep laboratory of a tertiary care center was examined. Adult patients who had undergone a diagnostic polysomnography and completed the Berlin questionnaire, a sleep questionnaire, and the Epworth sleepiness scale were selected. Multiple logistic regression analysis was performed to assess the relationship between OSA-associated symptoms and different potential explanatory variables. The study sample included 1084 patients, median age was 53 years, 46.5% (504) were women, 72.7% (788) had OSA (apnea/hypopnea index ≥ 5), and 31.2% were obese. After adjusting for age, body mass index, and apnea/hypopnea index, men were more likely to report snoring (OR 4.06, p

Background Patients under treatment with continuous positive airway pressure (CPAP) may have residual sleep apnea (RSA).

The aim of the study was to validate the automatic and manual analysis of ApneaLink Ox™ (ALOX) in patients with suspected obstructive sleep apnea (OSA). All patients with suspected OSA had a polysomnography (PSG) and an ALOX performed in the sleep laboratory. For automatic analysis, hypopnea was defined as a decrease in airflow ≥30 % of baseline for at least 10 s plus oxygen desaturation ≥3 or 4 %. While for the manual analysis, hypopnoea was considered when a reduction of airflow ≥30 % of ≥10 s plus oxygen desaturation ≥3 % or increase in cardiac rate ≥5 beats/min were identified or, when only a reduction of airflow ≥50 % was observed. OSA was defined as a respiratory disturbance index (RDI) ≥5. The apnea/hypopnea automatic index (AHI3-a, AHI4-a) and manual index were estimated. Receiver operating characteristics (ROC) analysis and the agreement between ALOX and PSG were performed. Fifty-five patients were included (38 men; mean age, 48.2; median, RDI 15.1; median BMI, 30 Kg/m2). The automatic analysis of ALOX under-estimated the RDI from PSG, mainly for the criterion of oxygen desaturation ≥4 % (AHI3-a–RDI, −3.6 ± 10.1; AHI4-a–RDI, −6.5 ± 10.9, p

There is scarce information about whether the diagnosis of OSA supported only by medical record data can be a useful and reliable tool to initiate a CPAP treatment. The aim of this study is to develop and assess the accuracy of clinical parameters for the diagnosis and prescription of CPAP in patients with suspected OSA. Adult patients who underwent polysomnography and completed the Berlin questionnaire, a clinical record, and the Epworth sleepiness scale were included in the study. A situation was simulated in which two blinded and independent observers would be able to indicate CPAP treatment if the patients were snorers with frequent apnea reports (≥3–4 times a week) and overweight (BMI > 25 kg/m2) plus one of the following: diurnal symptoms (tiredness after sleeping or at waking time ≥3–4 times a week or Epworth sleepiness scale >11), arterial hypertension, cerebrovascular accident, coronary event, type II diabetes or cardiac arrhythmias (observer 1, clinical criteria) or on the basis of the respiratory disturbance index, significant tiredness (≥3–4 times a week) or sleepiness (Epworth >11) and associated comorbidities (observer 2, reference method). The area under the ROC curve (ABC-ROC), sensitivity, specificity, and likelihood ratios were calculated. Among 516 subjects (72 % men), the median age was 52 years, BMI 28.3 kg/m2, and RDI 19.7 events/h. The ABC-ROC, sensitivity, specificity, and positive likelihood ratio of the clinical parameters were of 0.64 to 0.65, 31 to 33 %, 97 to 98 %, and 11 to15 respectively. No differences in the diagnostic performance of the clinical criteria were observed between men and women. These clinical parameters made it possible to indicate CPAP in approximately one third of the population with OSA which would have required it on the basis of their PSG and clinical history. This approach showed high specificity; hence, few patients who did not meet the criteria for CPAP use would have received this treatment.

Objective.To evaluate the accuracy and reliability of the medical decision based on the results of the hand scoring from a two-channel recording device (ApneaLink) plus clinical data for the prescription of a CPAP assay in patients with suspected OSA.Methods.39 subjects were assessed in the sleep laboratory with polysomnography and ApneaLink. The patients completed the Epworth sleepiness scale and a clinical history. Two blinded independent observers decided to prescribe CPAP according to the results of the PSG (gold standard, observer A), ApneaLink (alternative method, observer B), and the clinical parameters. Sensitivity and specificity of observer B on the indication of CPAP were calculated. The interobserver agreement for the indication of CPAP was assessed using kappa statistics.Results.38 subjects were included (26 men, mean age 47.5, mean RDI 28.7, mean BMI 31.4 kg/m2). The prevalence of OSA was 84%. The sensitivity and specificity of observer B to initiate a CPAP trial were 90.6% and 100%, respectively. The interrater agreement for the prescription of CPAP was good (kappa: 0.75).Conclusion.This study has shown that the use of ApneaLink plus clinical data has made it possible to indicate CPAP reliably in most patients with high-clinical pretest for OSA.

Objective. To assess the diagnostic ability of WristOx 3100 using its three different recording settings in patients with suspected obstructive sleep apnea syndrome (OSAS).Methods. All participants (135) performed the oximetry (three oximeters WristOx ) and polysomnography (PSG) simultaneously in the sleep laboratory. Both recordings were interpreted blindly. Each oximeter was set to one of three different recording settings (memory capabilities 0.25, 0.5, and 1 Hz). The software (nVision 5.1) calculated the adjusted O2desaturation index-mean number of O2desaturation per hour of analyzed recording ≥2, 3, and 4% (ADI2, 3, and 4). The ADI2, 3, and 4 cutoff points that better discriminated between subjects with or without OSAS arose from the receiver-operator characteristics (ROCs) curve analysis. OSAS was defined as a respiratory disturbance index (RDI) ≥ 5.Results. 101 patients were included (77 men, mean age 52, median RDI 22.6, median BMI 27.4 kg/m2). The area under the ROCs curves (AUC-ROCs) of ADI2, 3, and 4 with different data storage rates were similar (AUC-ROCs with data storage rates of 0.25/0.5/1 Hz: ADI2: 0.958/0.948/0.965, ADI3: 0.961/0.95/0.966, and ADI4: 0.957/0.949/0.963,PNS).Conclusions. The ability of WristOx 3100 to detect patients with OSAS was not affected by the data storage rate of the oxygen saturation signal. Both memory capacity of 0.25, 0.5, or 1 Hz showed a similar performance for the diagnosis of OSAS.

The aim of this study was to assess the accuracy of oximetry and the clinical parameters for the prescription of continuous positive airway pressure (CPAP) in patients with suspected obstructive sleep apnea syndrome (OSAS).All participants (135) performed oximetry (WristOx 3100™) and polysomnography (PSG) simultaneously in the sleep laboratory. The patients completed the Epworth sleepiness scale, the Berlin questionnaire, and a clinical history. Two blind independent observers decided to prescribe CPAP according to the results of the PSG (gold standard, observer A), oximetry (alternative method, observer B), and the clinical parameters. The accuracy of observer B on the indication of CPAP, using different cutoff points of the adjusted desaturation index (ADI3 and ADI4), was evaluated by the area under the receiver operating characteristics curve (AUC-ROC). The interobserver agreement for the indication of CPAP was assessed using kappa statistics.One hundred nineteen subjects were included (92 men; mean age, 53; median respiratory disturbance index, 22.6; median BMI, 27.5 kg/m(2)). Depending on the criteria used in oximetry, the sensitivity and specificity of observer B to initiate a CPAP trial ranged from 79.8% to 92.5% and of 92% to 96%, respectively. The best performance for the indication of CPAP was noted with the adjusted O(2) desaturation index ≥ 3% (AUC-ROC, 0.923). The inter-rater agreement for the prescription of CPAP was good (kappa, 0.60 to 0.79).This simulated study has shown that the use of oximetry plus clinical data has made it possible to indicate CPAP reliably in nearly 90% of the population with OSAS.

To evaluate the diagnostic accuracy of the Nonin WristOx 3100 and its software (nVision 5.0) in patients with suspicion of sleep apnea/hypopnea syndrome (SAHS).All participants (168) had the oximetry and polysomnography simultaneously. The two recordings were interpreted blindly. The software calculated: adjusted O(2) desaturation index [ADI]-mean number of O(2) desaturation per hour of total recording analyzed time ofor = 2%, 3%, 4%, 5%, and 6% (ADI2, 3, 4, 5, and 6) and AT90-accumulated time at SO(2)90%. The ADI2, 3, 4, 5, and 6 and the AT90 cutoff points that better discriminated between subjects with or without SAHS arose from the receiver operating characteristic curve analysis. The sensitivity (S), specificity (E), and positive and negative likelihood ratio (LR+, LR-) for the different thresholds for ADI were calculated.One hundred and fifty-four patients were included (119 men, mean age 51, median apnea/hypopnea index [AHI] 14, median body mass index [BMI] 28.3 kg/m(2)). The best cutoff points of ADI were: SAHS = AHIor = 5: ADI219.3 (S 89%, E 94%, LR+ 15.5 LR- 0.11); SAHS =AHIor = 10: ADI310.5 (S 88%, E 94%, LR+ 15 LR- 0.12); SAHS = AHIor = 15: ADI313.4 (S 88%, E 90%, LR+ 8.9, LR- 0.14). AT90 had the lowest diagnosis accuracy. An ADI2or = 12.2 excluded SAHS (AHIor = 5 and 10; S 100%, LR- 0) and ADI34.3 (AHIor = 5 and 10) or 32 (AHIor = 15) confirmed SAHS (E 100%).A negative oximetry defined as ADI2or = 12.2 excluded SAHS defined as AHIor = 5 or 10 with a sensitivity and negative likelihood ratio of 100% and 0%, respectively. Furthermore, a positive oximetry defined as an ADI332 (SAHS = AHIor = 15) had a specificity of 100% to confirm the pathology.

The objective was to determine the effect of inhaled salbutamol on PEEPi dyn in spontaneously breathing patients with stable severe chronic obstructive pulmonary disease (COPD).Eleven patients with COPD were studied (mean age: 63 years, average FEV1 0.71 +/- 0.31 L). The patients were evaluated before and after inhaling 400 pg of salbutamol. Spirometry, slow vital capacity, breathing pattern, and PEEPi dyn pre- and post-bronchodilator administration were performed. PEEPi dyn was measured as the difference in esophageal pressure between the onset of inspiratory effort and the point of zero flow.Pre-BD PEEPi dyn fell on average by 56% after inhalation of salbutamol (1.89 +/- 1.24 cm H2O to 0.83 +/- 0.81 cm H2O, p0.001). This was accompanied by bronchodilation and a reduction of air trapping (FEV1: 0.71 +/- 0.31 L to 0.91 +/- 0.35 L, p0.001; IC: 1.5 +/- 0.53 L to 1.94 +/- 0.56 L, p0.001). A significant positive correlation between deltaPEEPi dyn, deltaFEV1 (r=0.64, p0.05), and deltaIC (r=0.69, p0.05) was observed. The breathing pattern did not change significantly after bronchodilation. Stepwise multiple regression analysis of pre-BD spirometric and breathing pattern parameters selected IC and Ti/Ttot as the strongest predictors of pre-BD PEEPi dyn (p=0.039 and 0.006, respectively).The inhalation of 400 microg of salbutamol produced bronchodilation, reduction of air trapping, and a decrease in PEEPi dyn in spontaneously breathing patients with stable severe COPD.

The aim of this study was to evaluate the relationship between the duration of arousal and the type, duration and minSaO(2) of apneas/hypopneas, and the time of night and sleep stage when they occurred.We measured the duration of arousals associated with apneas (A) and hypopneas (H) in 10 polysomnographic recording. Arousals were categorized as: 1) Short Electroencephalographic Arousal (SEA: 3-15 s) and 2) Awakenings (15 s). The dependent variable for multiple logistic regression analysis was duration of arousal (0 = 3-11 s, 1 =11 s); the independent variables were event (0 = H, 1 = A), event duration (0 = 10-20 s, 1 =20 s), sleep stage (0 = REM, 1 = NREM 1-2); minSaO(2) (0 = 86%, 1 =86%) and time of night (0 = at or before 3:00 AM, 1 = after 3:00 AM).We analyzed 1536 apneas and hypopneas. 80.3% had arousal, 61% SEA and 19.3% awakenings. The median duration of arousal was higher in apneas (A: 12 s, H: 9.2 s, p0.001). The apneas and events20 s with a minSaO(2)86% had a higher probability of arousal11 s (apnea: OR 2.1, p0.001; events20 s: OR 1.5, p0.01; minSaO(2)86%: OR 1.4, p0.05).Arousals were greater in apneas than in hypopneas. Apneas and events20 s with a minSaO(2)86% were associated more frequently with arousal11 s.

According to recent reports, sleep disorders affect 30% of the adult population and 5-10% of children. Obstructive Sleep Apnea Hypopnea Syndrome (OSA) has a considerable epidemiological impact and demand for consultation is growing in our community. Therefore, it is necessary to know the principles of interpretation of diagnostic methods. A suspicion of OSA requires confirmation. According to the guidelines of the Argentine Association of Respiratory Medicine, polysomnography (PSG) is the gold standard for OSA diagnosis, while home sleep testing (HST) can be accepted as a comparatively effective method depending on the clinical situation of the patient. This article questions the use of AHI (apnea-hypopnea index) as the only measurement needed to diagnose OSA and assess its severity. In fact, it is surprising that, despite the large mass of data analyzed during sleep studies, current practices only focus on AHI. More than four decades have passed since OSA was first described. Our tendency to oversimplify complex conditions may prevent us from gaining a deeper and more thorough understanding of OSA. The development and validation of OSA severity scoring systems based on multiple parameters is still a pending issue.

Introduction: Patients that started on Non-Invasive Ventilation (NIV) need to define several parameters selected on the basis of diurnal arterial blood gas and underlying disease. We hypothesize that respiratory polygraphy (RP) could be useful to monitor NIV. This retrospective work describes RP findings and their impact on the setting of continuous flow ventilators from patients on NIV of Intensive Care Unit (ICU). Material and Methods: Patient's data on NIV from at the ICU of Hospital Británico were included in this study. RP recordings were performed in all of them. Respiratory events, such as ventilatory pattern changes, impact on oximetry or tidal volume, were observed to modify the ventilatory mode after RP. Results: The RP findings have contributes to change the ventilatory mode for one third of the patients. The mean values of expiratory positive airway pressure (EPAP) and inspiratory positive airway pressure (IPAP) were not significantly different across all the population before or after RP: 8.7±0.3 vs. 8.6±0.4; p 2 cmH2O pressure value changes after RP. Conclusions: RP recordings could contribute to broad range of data useful to make decisions about changes in programming and allowed to identify adverse events related to positive pressure.

Due to the increased interest of the medical community in sleep disorders an experts meeting was called to establish common criteria for diagnosis, treatment and management of these disorders. Adult prevalence of sleep apnea/hypopnea syndrome (SA/HS) is about 2-4% and increases in the elderly. Snoring and excessive daytime somnolence (EDS) are habitual symptoms. Increased risk to cardiovascular disorders and traffic accidents are the major complications. Increased upper airways resistance syndrome is a recently described syndrome which also involves EDS. A standardized questionnaire was developed and its use was recommended in order to evaluate patients with respiratory sleep disorders (RSD). Polysomnography was established as gold standard in the diagnosis of RSD. Minimal requirement of split night studies and screening studies was also standardized and specific indications were summarized. Medical treatment of obesity in relationship to RSD was analyzed. Nasal continuous positive airways pressure (CPAP) was established as the first choice treatment of SA/HS. Titration of CPAP was standardized. Oral appliances with mandibular advancement could be considered in the treatment of snoring patients without SA/HS and in patients with increased upper airways resistance syndrome. Uvulopalatopharingoplasty can only be performed in snoring patients in whom the presence of SA/HS has been dismissed by polysomnography. Management of patients must include periodic clinical control. EDS must be determined by Epworth test. In order to evaluate CPAP compliance the use of time-controlled devices is highly recommended.

Obesity is one of the main predisposing factors for obstructive sleep apnea (OSA) hypopnea syndrome. It has been described that body mass index (BMI) influences the accuracy of oxygen desaturation index (ODI) for the diagnosis of OSA by polysomnography (PSG). We analyzed the relationship between traditional indicators: apnea-hypopnea index (AHI) and ODI in a population at high risk for OSA, by respiratory polygraphy (RP) and PSG. This is a retrospective study of 1898 patients with suspicion of OSA, from which 1053 underwent RP and 582 underwent PSG with OSA. We compared results considering gender, age, and degree of obesity. This study included 1333 records of patients with OSA—more than 80 % of whom were overweight or obese. We observed that AHI and ODI increased progressively with obesity grade and said increase was associated with BMI only in men. The evaluation of the agreement between AHI and ODI found a difference between normal weight and obese patients, regardless of gender. Study findings contribute to understand the role of oximetry in the diagnosis of OSA in obese patients. Our results were observed using full PSG and a simplified home method. The correlation between these indicators could improve our clinical interpretation of OSA severity among obese patients when abbreviated tests are used.