Anticoagulation strategies and risk of bleeding events in critically ill COVID-19 patients / Estrategias de anticoagulación y riesgo de sangrado en pacientes ingresados en una Unidad de Cuidados Intensivos por COVID-19

Objective To evaluate the rate of thrombosis, bleeding and mortality comparing anticoagulant doses in critically ill COVID-19 patients. Design Retrospective observational and analytical cohort study. Setting COVID-19 patients admitted to the intensive care unit of a tertiary hospital between March and April 2020. Patients 201 critically ill COVID-19 patients were included. Patients were categorized into three groups according to the highest anticoagulant dose received during hospitalization: prophylactic, intermediate and therapeutic. Interventions The incidence of venous thromboembolism (VTE), bleeding and mortality was compared between groups. We performed two logistic multivariable regressions to test the association between VTE and bleeding and the anticoagulant regimen. Main variables of interest VTE, bleeding and mortality. Results 78 patients received prophylactic, 94 intermediate and 29 therapeutic doses. No differences in VTE and mortality were found, while bleeding events were more frequent in the therapeutic (31%) and intermediate (15%) dose group than in the prophylactic group (5%) (p<0.001 and p<0.05 respectively). The anticoagulant dose was the strongest determinant for bleeding (odds ratio 2.4, 95% confidence interval 1.26–4.58, p=0.008) but had no impact on VTE. Conclusion Intermediate and therapeutic doses appear to have a higher risk of bleeding without a decrease of VTE events and mortality in critically ill COVID-19 patients (AU)

Objetivo Evaluar la incidencia de eventos trombóticos, sangrado y mortalidad comparando diferentes regímenes de anticoagulación en pacientes ingresados en unidades de Cuidados Intensivos (UCI) por COVID-19. Diseño Estudio de cohortes retrospectivo observacional y analítico. Ámbito Pacientes con COVID-19 ingresados en una UCI de un hospital terciario entre marzo y abril del 2020. Pacientes Se incluyó a un total de 201 pacientes de UCI ingresados por COVID-19. Los pacientes se categorizaron en 3 grupos en función de la dosis de anticoagulación más alta recibida durante el ingreso: profiláctica, intermedia y terapéutica. Intervenciones Se comparó la incidencia de eventos trombóticos, hemorragia y mortalidad entre los grupos. Se realizaron 2 regresiones logísticas multivariables para comprobar la asociación entre los eventos trombóticos y el sangrado con el régimen anticoagulante. Principales variables de interés Eventos trombóticos, sangrado y mortalidad. Resultados De los pacientes incluidos, 78 recibieron dosis profilácticas, 94 intermedias y 29 terapéuticas. No se encontraron diferencias en los eventos trombóticos y la mortalidad entre grupos, mientras que los sangrados fueron más frecuentes en el grupo de dosis terapéutica (31%) e intermedia (15%) que en el grupo de dosis profiláctica (5%) (p <0,001 y p <0,05, respectivamente). El régimen anticoagulante fue el mayor determinante de sangrado (odds ratio 2,4;, intervalo de confianza del 95%, 1,26-4,58; p=0,008) pero no tuvo ningún impacto en los eventos trombóticos. Conclusiones Las dosis intermedias y terapéuticas parecen tener un mayor riesgo de sangrado sin una disminución de los eventos trombóticos ni la mortalidad en pacientes de UCI con COVID-19 (AU)

Anticoagulation strategies and risk of bleeding events in critically ill COVID-19 patients.

OBJECTIVE: To evaluate the rate of thrombosis, bleeding and mortality comparing anticoagulant doses in critically ill COVID-19 patients. DESIGN: Retrospective observational and analytical cohort study. SETTING: COVID-19 patients admitted to the intensive care unit of a tertiary hospital between March and April 2020. PATIENTS: 201 critically ill COVID-19 patients were included. Patients were categorized into three groups according to the highest anticoagulant dose received during hospitalization: prophylactic, intermediate and therapeutic. INTERVENTIONS: The incidence of venous thromboembolism (VTE), bleeding and mortality was compared between groups. We performed two logistic multivariable regressions to test the association between VTE and bleeding and the anticoagulant regimen. MAIN VARIABLES OF INTEREST: VTE, bleeding and mortality. RESULTS: 78 patients received prophylactic, 94 intermediate and 29 therapeutic doses. No differences in VTE and mortality were found, while bleeding events were more frequent in the therapeutic (31%) and intermediate (15%) dose group than in the prophylactic group (5%) (p<0.001 and p<0.05 respectively). The anticoagulant dose was the strongest determinant for bleeding (odds ratio 2.4, 95% confidence interval 1.26-4.58, p=0.008) but had no impact on VTE. CONCLUSIONS: Intermediate and therapeutic doses appear to have a higher risk of bleeding without a decrease of VTE events and mortality in critically ill COVID-19 patients.

Fibrobroncoscopia en una unidad de vigilancia intensiva respiratoria / Fiberoptic bronchoscopy in a respiratory intensive care unit

Objetivo: Describir las indicaciones, rentabilidad diagnóstica y complicaciones de la fibrobroncoscopia (FBS) en una unidad de vigilancia intensiva respiratoria (UVIR). Diseño: Estudio prospectivo observacional. Ámbito: UVIR de 6 camas en un hospital universitario de tercer nivel. Pacientes: Pacientes admitidos en una UVIR a los que se les realizó una FBS. Intervenciones: Ninguna. Variables de interés: Indicaciones y complicaciones de la FBS, técnicas endoscópicas realizadas y tiempo empleado en la FBS. Resultados: Se realizaron 107 (23%) FBS a 69 de los 297 pacientes admitidos en la UVIR. El 68% de las FBS se practicaron a pacientes con ventilación mecánica. La FBS se realizó con fines diagnósticos en 88 ocasiones (82%) y terapéuticos en 19 (18%). La indicación más frecuente para la FBS diagnóstica fue el estudio de infiltrados pulmonares (44 casos; 50%), particularmente en pacientes inmunodeprimidos (24 casos; 27%). Para esta indicación, la rentabilidad diagnóstica de la FBS fue significativamente mejor en los pacientes inmunodeprimidos, respecto a los inmunocompetentes (48% vs 30%; p<0,01). La FBS no causó complicaciones mayores; únicamente se observó un descenso significativo en la PaO2/FiO2 (182±74 vs 163±79; p<0,005) cuando se realizó un lavado broncoalveolar. La mortalidad global en la UVIR fue del 14%; del 25% en los pacientes que precisaron FBS y del 45% en aquellos que precisaron FBS adicionales. Conclusiones: La FBS es un procedimiento seguro y rápido que se utiliza con frecuencia en la UVIR y que contribuye significativamente al manejo clínico. Los pacientes de la UVIR que requieren FBS adicionales tienen una elevada mortalidad (AU)

Objective: To describe the indications, diagnostic performance and safety of fiberoptic bronchoscopy (FOB) performed in a respiratory intensive care unit (RICU). Design: A prospective, observational study was carried out. Setting: A 6-bed RICU in a tertiary university hospital. Patients: Patients admitted to RICU who required FOB. Interventions: None. Main measurements: FOB indications and complications, endoscopic procedures, time required to perform FOB. Results: Sixty-nine out (23%) of the 297 patients admitted to the RICU underwent a total of 107 FOB. Sixty-eight percent of FOB were performed in patients on mechanical ventilation. FOB was performed for diagnostic and therapeutic purposes in 88 (82%) and 19 cases (18%), respectively. The study of pulmonary infiltrates was the main indication for diagnostic FOB (44 cases; 50%), particularly in immunocompromised patients (24 cases; 27%). In immunocompromised patients the diagnostic performance of FOB was significantly higher than in immunocompetent subjects (48% vs 30%; p<0.01). No major complications were recorded. Only a significant drop in PaO2/FiO2 ratio was observed (182±74 vs 163±79; p<0.005) in patients undergoing bronchoalveolar lavage. Overall mortality in patients in the RICU was 14%. In patients requiring a single FOB procedure, mortality was 25%, versus 45% among those requiring more than one FOB procedure. Conclusions: These results show that FOB is used commonly in the RICU. It is a safe and fast procedure that contributes significantly to clinical management. Patients requiring additional FOB during admission to the RICU show high mortality (AU)

[Fiberoptic bronchoscopy in a respiratory intensive care unit]. / Fibrobroncoscopia en una unidad de vigilancia intensiva respiratoria.

OBJECTIVE: To describe the indications, diagnostic performance and safety of fiberoptic bronchoscopy (FOB) performed in a respiratory intensive care unit (RICU). DESIGN: A prospective, observational study was carried out. SETTING: A 6-bed RICU in a tertiary university hospital. PATIENTS: Patients admitted to RICU who required FOB. INTERVENTIONS: None. MAIN MEASUREMENTS: FOB indications and complications, endoscopic procedures, time required to perform FOB. RESULTS: Sixty-nine out (23%) of the 297 patients admitted to the RICU underwent a total of 107 FOB. Sixty-eight percent of FOB were performed in patients on mechanical ventilation. FOB was performed for diagnostic and therapeutic purposes in 88 (82%) and 19 cases (18%), respectively. The study of pulmonary infiltrates was the main indication for diagnostic FOB (44 cases; 50%), particularly in immunocompromised patients (24 cases; 27%). In immunocompromised patients the diagnostic performance of FOB was significantly higher than in immunocompetent subjects (48% vs 30%; p<0.01). No major complications were recorded. Only a significant drop in PaO(2)/FiO(2) ratio was observed (182 ± 74 vs 163 ± 79; p<0.005) in patients undergoing bronchoalveolar lavage. Overall mortality in patients in the RICU was 14%. In patients requiring a single FOB procedure, mortality was 25%, versus 45% among those requiring more than one FOB procedure. CONCLUSIONS: These results show that FOB is used commonly in the RICU. It is a safe and fast procedure that contributes significantly to clinical management. Patients requiring additional FOB during admission to the RICU show high mortality.

Antibiotic prescription for community-acquired pneumonia in the intensive care unit: impact of adherence to Infectious Diseases Society of America guidelines on survival.

BACKGROUND: The purpose of our study was to analyze prognostic factors associated with mortality for patients with severe community-acquired pneumonia (CAP). METHODS: We conducted a prospective multicenter study including all patients with CAP admitted to the intensive care unit during a 15-month period in 33 Spanish hospitals. Admission data and data on the evolution of the disease were recorded. Multivariate analysis was performed using the SPSS statistical package (SPSS). RESULTS: A total of 529 patients with severe CAP were enrolled; the mean age (+/-SD) was 59.9+/-16.1 years, and the mean Acute Physiology and Chronic Health Evaluation (APACHE) II score (+/-SD) was 18.9+/-7.4. Overall mortality among patients in the intensive case unit was 27.9% (148 patients). The rate of adherence to Infectious Diseases Society of America (IDSA) guidelines was 57.8%. Significantly higher mortality was documented among patients with nonadherence to treatment (33.2% vs. 24.2%). Multivariate analysis identified age (odds ratio [OR], 1.7), APACHE II score (OR, 4.1), nonadherence to IDSA guidelines (OR, 1.6), and immunocompromise (OR, 1.9) as the variables present at admission to the intensive care unit that were independently associated with death in the intensive care unit. In 15 (75%) of 20 cases of Pseudomonas aeruginosa infection, the antimicrobial treatment at admission was inadequate (including 8 of 15 cases involving patients with adherence to IDSA guidelines). Chronic obstructive pulmonary disease (OR, 17.9), malignancy (OR, 11.0), previous antibiotic exposure (OR, 6.2), and radiographic findings demonstrating rapid spread of disease (OR, 3.9) were associated with P. aeruginosa pneumonia. CONCLUSIONS: Better adherence to IDSA guidelines would help to improve survival among patients with severe CAP. Pseudomonas coverage should be considered for patients with chronic obstructive pulmonary disease, malignancy, or recent antibiotic exposure.

Forced oscillation measurements do not affect upper airway muscle tone or sleep in clinical studies.

Upper airway obstruction in the sleep apnoea/hypopnoea syndrome (SAHS) can be easily assessed by measuring respiratory impedance with the forced oscillation technique (FOT). This methodology has been proposed as a useful clinical tool both for the diagnosis of sleep breathing disorders and for continuous positive airway pressure (CPAP) titration. However, previous studies suggest that the application of high-frequency pressure oscillation to the upper airway may induce changes in the electroencephalogram (EEG) or upper airway muscle function. The effect of FOT measurements on upper airway muscle tone and EEG in clinical sleep studies was examined. Seven patients with moderate SAHS were included (age: 54+/-11 yrs; apnoea/hypopnoea index: 43+/-21 events x h(-1); body mass index: 30+/-2 kg x m(-2)). Genioglossus surface electromyogram activity (EMGgg) and EEG signal were analysed with and without FOT application (frequency: 5 Hz and 30 Hz; peak-to-peak pressure oscillation: 1 cmH2O) during stable sleep. Measurements were carried out in two different situations. Step 1: applying FOT during episodes of obstructive events or flow limitation; and step 2: during prolonged periods of normal breathing at optimal CPAP. The root mean square of EMGgg activity and fast Fourier analysis (alpha and delta bands) of the EEG signal were performed. The application of FOT did not increase EMGgg activity in any of the situations studied. In addition, no evidence of the effects on EEG was found: alpha/delta relationship: awake:0.70, baseline sleep:0.13, FOT(5 Hz):0.18, FOT(30 Hz):0.11. The presented results suggest that the use of forced oscillation technique over the ranges of frequency and amplitude proposed for clinical sleep studies does not induce changes in upper airway muscle activity and neurological variables in patients with sleep apnoea/hypopnoea syndrome.

Terapéutica del síndrome de apneas e hipopneas durante el sueño

Existen todavía muchos aspectos por clarificar en la relación entre los trastornos obstructivos del sueño, su historia natural y la morbilidad y mortalidad asociadas con esta enfermedad. Por todo ello, la mayoría de guías clínicas, recomendaciones y estrategias terapéuticas son necesariamente generales, están presididas por la prudencia y permiten un amplio margen de maniobra individualizando en cada caso las decisiones de tratamiento. (AU)

Effectiveness of CPAP treatment in daytime function in sleep apnea syndrome: a randomized controlled study with an optimized placebo.

Application of continuous positive airway pressure (CPAP) as the standard treatment for sleep apnea/hypopnea syndrome (SAHS) is a moot point. Studies on the effectiveness of this treatment have been challenged because of the lack of a suitable placebo. The recent description of a true placebo (sham CPAP) prompted us to conduct a randomized trial of CPAP or placebo to assess the effectiveness of CPAP in improving SAHS-related symptoms and daytime function in patients with moderate to severe SAHS. Forty-eight patients, stratified in four groups according to severity, were randomly allocated into two treatment groups (optimal and sham CPAP) for a 6-wk period. Of these, 45 completed follow-up (91% males; age: 54 +/- 10 yr; body mass index [BMI]: 32 +/- 6 kg/m(2); apnea-hypopnea index [AHI]: 54 +/- 19 events/h; and Epworth Sleepiness Scale [ESS]: 16 +/- 5). The ESS, a questionnaire on SAHS-related symptoms, Functional Outcomes Sleep Questionnaire (FOSQ), and the Short Form Health Survey (SF-36) were completed at inclusion and after treatment. After 10 d of washout, the placebo group was treated with optimal CPAP and reassessed before and after optimal CPAP. The group receiving optimal CPAP when compared with the group with sham CPAP showed considerably greater improvement in the relief of sleepiness (-9.5 versus -2.3, p < 0.001), other SAHS-related symptoms (-18.5 versus -4.5, p < 0.001), vigilance (+8.5 versus +3.4, p = 0.009), and general productivity (+4.0 versus +0.5, p = 0.04) FOSQ scales. Both groups used a similar number of hours for the optimal and the sham CPAP (4.3 versus 4.5, (p = NS). The patients initially treated with placebo CPAP improved significantly more when optimal CPAP was applied for ESS (-2.3 versus -6.7, p < 0.001) and other sleep apnea syndrome (SAS)-related symptoms (-4.5 versus -11.2, p = 0.02). Our study provides strong evidence of the effectiveness of CPAP treatment in improving symptoms and perceived health status in moderate to severe SAHS.

Performance of nasal prongs in sleep studies : spectrum of flow-related events.

OBJECTIVES: The use of nasal prongs connected to a pressure transducer is a noninvasive, sensitive method to detect respiratory events, and can be easily implemented in routine sleep studies. Moreover, its good time response allows the detection of several flow-related phenomena of high interest, in addition to apnea and hypopnea. The aims of the study were to examine the quality and performance of the nasal prong flow signal, and to describe other flow-related events during full-night polysomnography studies. METHODS: Twenty-seven subjects were studied (16 male subjects; mean +/- SD age, 49 +/- 14 years; mean body mass index, 27 +/- 4 kg/m(2)): 15 subjects recruited from the general population and 12 consecutive patients with suspected sleep apnea/hypopnea syndrome (SAHS). RESULTS: A blind analysis of the respiratory events detected both by nasal prongs and thermistor was done. The quality of the nasal prong signal recordings was considered optimal for scoring purposes in 78% of cases, and no recording was considered uninterpretable. The nasal prong signal detected additional flow-related events not observed by the thermistor: (1) short and long (> 2 min) periods of inspiratory flow limitation morphology without decrease in the amplitude of the signal; (2) periods of mouth expiration; and (3) snoring. The apnea/hypopnea index was significantly higher with the nasal prong scoring (18 vs 11 [p < 0.05] in the general population and 37 vs 27 [p < 0.001] in the group with suspected SAHS). CONCLUSIONS: The incorporation of nasal prongs in routine full-night studies is an attainable technical option that provides adequate recordings in most cases. Additionally, relevant information not scored by thermistors is obtained on flow-related respiratory events, thus increasing diagnostic accuracy.

Clinical application of the forced oscillation technique for CPAP titration in the sleep apnea/hypopnea syndrome.

We have previously demonstrated that upper airway obstruction in sleep apnea/hypopnea syndrome (SAHS) can be accurately assessed in real-time by measuring respiratory impedance (|Z|) with the forced oscillation technique (FOT). The aims of the present study were: (1) to determine the feasibility of identifying the optimal continuous positive airway pressure (CPAP) for patients with SAHS based on analysis of the |Z| signal during conventional polysomnographic CPAP titration studies; and (2) to evaluate practical issues involved in the application of FOT during CPAP titration. We performed CPAP titration in 28 patients with SAHS during polysomnography (PSG) (14 nap and 14 full overnight studies) using a FOT system applied continuously to obtain an on-line measurement of |Z|. FOT was easily implemented and was well-tolerated by the patients. Optimal CPAP levels were determined both in the conventional manner from the standard PSG titration record and during a separate blinded analysis using the FOT signal alone. The mean conventional versus FOT-based optimal CPAP values were similar for both nap studies (10.6 +/- 0.6 [mean +/- SEM] versus 11.1 +/- 0.6 cm H(2)O, respectively, p = 0. 054) and overnight studies (9.9 +/- 0.7 versus 9.9 +/- 0.6 cm H(2)O, respectively, p = 1.00). Subsequent analysis of the PSG record with the FOT signal incorporated demonstrated that artefacts in the |Z| tracing occurred during mask leak, mouth breathing, and movement during arousal. Such abnormalities were readily identified from the flow tracing. These results indicate that, for adequate interpretation, the tracing and values of respiratory impedance obtained by FOT should be evaluated in conjunction with the flow signal. Continuous FOT-guided CPAP titration is feasible and may be a useful adjunct during manual titration. FOT could also potentially serve as the basis for automated CPAP in SAHS.

Evidence of the effectiveness of continuous positive airway pressure in the treatment of sleep apnea/hypopnea syndrome.

Continuous positive airway pressure (CPAP) is worldwide considered as the standard treatment of sleep apnea/hypopnea syndrome (SAHS) although studies on the effectiveness of this treatment are limited. The aim of our study was to evaluate the effectiveness of CPAP in improving SAHS-related symptoms, daytime function, perceived health status, and quality of life in patients with moderate to severe SAHS. The effect of conservative treatment (CT) measures-sleep hygiene and weight loss- was compared with CT + CPAP. We included 105 consecutive patients (13 females, age 53 +/- 10 yr, body mass index [BMI] = 32 +/- 6 kg/m2, apnea/hypopnea index [AHI] = 56 +/- 20, Epworth sleepiness scale [ESS] = 12 +/- 5) who met our criteria for CPAP treatment. Patients were randomly allocated in two groups of similar characteristics. Group 1 (n = 37) was asked to improve sleep hygiene and started a weight loss program. Group 2 (n = 68) received, in addition, treatment with CPAP. Both groups were followed through weekly telephone calls and appointments. Sleepiness, other symptoms related to SAHS, daytime function, perceived health status, and quality of life were assessed through questionnaires at inclusion and after 3 mo of treatment. The relief of sleepiness and other SAHS-related clinical symptoms and improvement in perceived health status was much greater in Group 2 receiving CT + CPAP compared with Group 1, only receiving CT. The odds of experiencing a treatment response with CPAP + CT compared with CT alone was 6.52 (odds ratio [OR] = 2.51 to 17.6, 95% confidence interval [95% CI]). CPAP is currently the treatment of choice. At this time, the indication of CPAP treatment in moderate to severe SAHS is adequately supported.

Upper airway resistance syndrome.

This article reviews the clinical picture, diagnosis and management of the upper airway resistance syndrome (UARS). Presently, there is not enough data on key points like the frequency of UARS and the morbidity associated with this condition. Furthermore, the existence of LIARS as an independent sleep disorder and its relation with snoring and obstructive events is in debate. The diagnosis of UARS is still a controversial issue. The technical limitations of the classic approach to monitor airflow with thermistors and inductance plethysmography, as well as the lack of a precise definition of hypopnea, may have led to a misinterpretation of UARS as an independent diagnosis from the sleep apnea/hypopnea syndrome. The diagnosis of this syndrome can be missed using a conventional polysomnographic setting unless appropriate techniques are applied. The use of an esophageal balloon to monitor inspiratory effort is currently the gold standard. However, other sensitive methods such as the use of a pneumotachograph and, more recently, nasal cannula/pressure transducer systems or on-line monitoring of respiratory impedance with the forced oscillation technique may provide other interesting possibilities. Recognition and characterization of this subgroup of patients within sleep breathing disorders is important because they are symptomatic and may benefit from treatment. Management options to treat UARS comprise all those currently available for sleep apnea/hypopnea syndrome (SAHS). However, the subset of patients classically identified as LIARS that exhibit skeletal craneo-facial abnormalities might possibly obtain further benefit from maxillofacial surgery.

Positional changes and drug interventions in acute respiratory failure.

Acute respiratory failure is often a life-threatening condition that determines the outcome of acutely ill patients. This review discusses the physiological basis and results of two complementary approaches for the management of such patients: positional changes and drug interventions. In unilateral pulmonary disease locating the healthy lung in a dependent position may improve gas exchange; in bilateral involvement, as occurs in the acute respiratory distress syndrome (ARDS), both the theoretical principles and the observed benefits fully support the use of the prone position. The effect of vasoactive drugs on pulmonary circulation and gas exchange is also reviewed. Selective vasodilators, such as inhaled nitric oxide and prostacycline-12, may provide a useful alternative in ARDS.

Forced oscillation technique for the evaluation of severe sleep apnoea/hypopnoea syndrome: a pilot study.

The forced oscillation technique (FOT) is a noninvasive method of potential clinical interest for quantitatively assessing airway mechanics during sleep. We investigated the applicability of FOT as a diagnostic tool for noninvasive assessment of airflow obstruction in patients with sleep apnoea/hypopnoea syndrome (SAHS) during sleep. In seven patients previously diagnosed with severe SAHS (mean+/-SD apnoea/ hypopnoea index (AHI) 67+/-14) we performed a full polysomnography (PSG) together with on-line measurement of respiratory impedance (IZI) using FOT. For each patient we determined: 1) number of respiratory events conventionally detected by full PSG, those obtained by FOT and their degree of concordance; and 2) the characteristics and values of IZI during the respiratory events. FOT was well tolerated and easily applied in conjunction with a conventional sleep setup. The mean number of respiratory events x h(-1) detected by PSG and FOT were 55+/-16 and 58+/-17, respectively, with a strong concordance. IZI increased from a baseline of 11+/-4 to 50+/-20 cmH2O x L(-1) x s during apnoea (mean+/-SD). In all but one patient intermittent increases of IZI occurred immediately before each obstructive apnoea. In four patients, the increases of IZI developed at end-expiration whereas in two others occurred during inspiration. During hypopnoea most of the patients showed decreases of IZI during expiration. In conclusion, forced oscillation technique can be used as a noninvasive and complementary tool for the diagnosis of respiratory events and provides an on-line quantitative approach for continuous monitoring of airflow obstruction during sleep in patients with sleep apnoea/hypopnoea syndrome.

Nasal prongs in the detection of sleep-related disordered breathing in the sleep apnoea/hypopnoea syndrome.

Conventional systems to monitor oronasal flow in sleep studies have traditionally relied on a thermistor signal. Our study was designed to verify whether nasal prongs (NP) connected to a pressure transducer could improve respiratory events detection in patients with sleep apnoea/hypopnoea syndrome (SAHS) compared to traditional systems. Sleep episodes from a 2 h conventional polysomnographic record plus NP signal obtained at random from eight patients (age: mean(+/-SD) 53(+/-12) yrs; body mass index (BMI): 29(+/-6) kg x m(-2); apnoea/hypopnoea index (AHI): 27(+/-20) events x h(-1)) were identified and used for analysis. An abnormal change in the pattern of any of the respiratory or neurological variables occurring during the observation period was defined as an episode. Each episode was registered and scored with concomitant scoring of the remaining variables. According to the episode definition three different profiles were established: 1) periods of reduction of ventilation in either variable without an arousal or cyclical desaturation, named nonpathological episode (NPE); 2) an idiopathic or nonrespiratory arousal (IA); and 3) a true respiratory event (TRE) defined as reduction or absence of flow demonstrated by either thermistor, thoraco-abdominal bands or NP accompanied by cyclical desaturation and/or arousal. For each TRE, its detection by thermistor, thoraco-abdominal bands or NP was established. A total of 877 sleep episodes were observed (42 NPE, 30 IA and 805 TRE). When compared to single or combined thermistor and bands approach, NP had the highest respiratory events detection rate, 779 (96.8%) versus 673 events (83.6%), respectively. Detection of respiratory-related arousals was also improved by NP and only 3% could account for mouth breathing respiration. It is concluded that nasal prongs improve the detection of respiratory events in patients with sleep respiratory disorders.

Shrinking lungs syndrome in systemic lupus erythematosus: improvement with inhaled beta-agonist therapy.

The pathogenesis and therapy of shrinking lungs syndrome in patients with systemic lupus erythematosus remains controversial. It has been previously reported that corticosteroid treatment can be effective. We report a patient with shrinking lungs syndrome who presented a good response to inhaled beta-agonist therapy. Therapeutic approach to this syndrome is discussed.