MELANIA DIRCE OLIVEIRA MARQUES
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- Phenotyping Pharyngeal Pathophysiology using Polysomnography in Patients with Obstructive Sleep Apnea(2018) SANDS, Scott A.; EDWARDS, Bradley A.; TERRILL, Philip I.; TARANTO-MONTEMURRO, Luigi; AZARBARZIN, Ali; MARQUES, Melania; HESS, Lauren B.; WHITE, David P.; WELLMAN, AndrewRationale: Therapies for obstructive sleep apnea (OSA) could be administered on the basis of a patient's own phenotypic causes (""traits"") if a clinically applicable approach were available. Objectives: Here we aimed to provide a means to quantify two key contributors to OSA-pharyngeal collapsibility and compensatory muscle responsiveness-that is applicable to diagnostic polysomnography. Methods: Based on physiological definitions, pharyngeal collapsibility determines the ventilation at normal (eupneic) ventilatory drive during sleep, and pharyngeal compensation determines the rise in ventilation accompanying a rising ventilatory drive. Thus, measuring ventilation and ventilatory drive (e.g., during spontaneous cyclic events) should reveal a patient's phenotypic traits without specialized intervention. We demonstrate this concept in patients with OSA (N = 29), using a novel automated noninvasive method to estimate ventilatory drive (polysomnographic method) and using ""gold standard"" ventilatory drive (intraesophageal diaphragm EMG) for comparison. Specialized physiological measurements using continuous positive airway pressure manipulation were employed for further comparison. The validity of nasal pressure as a ventilation surrogate was also tested (N = 11). Measurements and Main Results: Polysomnography-derived collapsibility and compensation estimates correlated favorably with those quantified using gold standard ventilatory drive (R = 0.83, P < 0.0001; and R = 0.76, P < 0.0001; respectively) and using continuous positive airway pressuremanipulation (R = 0.67, P < 0.0001; and R = 0.64, P < 0.001; respectively). Polysomnographic estimates effectively stratified patients into high versus low subgroups (accuracy, 69-86% vs. ventilatory drive measures; P < 0.05). Traits were near-identical using nasal pressure versus pneumotach (N = 11, R >= 0.98, both traits; P < 0.001). Conclusions: Phenotypes of pharyngeal dysfunction in OSA are evident from spontaneous changes in ventilation and ventilatory drive during sleep, enabling noninvasive phenotyping in the clinic. Our approach may facilitate precision therapeutic interventions for OSA.
conferenceObject Retropalatal and Retroglossal Airway Compliance and Negative Effort Dependence in Patients with Obstructive Sleep Apnea(2018) MARQUES, M. O.; GENTA, P.; AZARBARZIN, A.; SANDS, S. A.; TARANTO-MONTEMURRO, L. T.; MESSINEO, L.; WHITE, D.; WELLMAN, A.- Retropalatal and retroglossal airway compliance in patients with obstructive sleep apnea(2018) MARQUES, Melania; GENTA, Pedro R.; AZARBARZIN, Ali; SANDS, Scott A.; TARANTO-MONTEMURRO, Luigi; MESSINEO, Ludovico; WHITE, David P.; WELLMAN, AndrewObjectives: We hypothesized that preferential retropalatal as compared to retroglossal collapse in patients with obstructive sleep apnea was due to a narrower retropalatal area and a higher retropalatal compliance. Patients with a greater retropalatal compliance would exhibit a recognizable increase in negative effort dependence (NED). Methods: Fourteen patients underwent upper airway endoscopy with simultaneous recordings of airflow and pharyngeal pressure during natural sleep. Airway areas were obtained by manually outlining the lumen. Compliance was calculated by the change of airway area from end-expiration to a pressure swing of -5 cm H2O. NED was quantified for each breath as [peak inspiratory flow minus flow at -5 cm H2O]/[peak flow] x 100. Results: Compared to the retroglossal airway, the retropalatal airway was smaller at end-expiration (p < 0.001), and had greater absolute and relative compliances (p < 0.001). NED was positively associated with retropalatal relative area change (r = 0.47; p < 0.001). Conclusions: Retropalatal airway is narrower and more collapsible than retroglossal airway. Retropalatal compliance is reflected in the clinically-available NED value.
conferenceObject Clinical Predictors of Respiratory System Loop Gain in Healthy Subjects and Patients with Obstructive Sleep Apnea(2018) MESSINEO, L.; TARANTO-MONTEMURRO, L. T.; AZARBARZIN, A.; MARQUES, M.; CALIANESE, N.; WHITE, D. P.; SANDS, S. A.; WELLMAN, A.- Quantifying the Arousal Threshold Using Polysomnography in Obstructive Sleep Apnea(2018) SANDS, Scott A.; TERRILL, Philip I.; EDWARDS, Bradley A.; MONTEMURRO, Luigi Taranto; AZARBARZIN, Ali; MARQUES, Melania; MELO, Camila M. de; LORING, Stephen H.; BUTLER, James P.; WHITE, David P.; WELLMAN, AndrewStudy Objectives: Precision medicine for obstructive sleep apnea (OSA) requires noninvasive estimates of each patient's pathophysiological ""traits."" Here, we provide the first automated technique to quantify the respiratory arousal threshold-defined as the level of ventilatory drive triggering arousal from sleep-using diagnostic polysomnographic signals in patients with OSA. Methods: Ventilatory drive preceding clinically scored arousals was estimated from polysomnographic studies by fitting a respiratory control model (Terrill et al.) to the pattern of ventilation during spontaneous respiratory events. Conceptually, the magnitude of the airflow signal immediately after arousal onset reveals information on the underlying ventilatory drive that triggered the arousal. Polysomnographic arousal threshold measures were compared with gold standard values taken from esophageal pressure and intraoesophageal diaphragm electromyography recorded simultaneously (N = 29). Comparisons were also made to arousal threshold measures using continuous positive airway pressure (CPAP) dial-downs (N = 28). The validity of using (linearized) nasal pressure rather than pneumotachograph ventilation was also assessed (N = 11). Results: Polysomnographic arousal threshold values were correlated with those measured using esophageal pressure and diaphragm EMG (R = 0.79, p < .0001; R = 0.73, p = .0001), as well as CPAP manipulation (R = 0.73, p < .0001). Arousal threshold estimates were similar using nasal pressure and pneumotachograph ventilation (R = 0.96, p < .0001). Conclusions: The arousal threshold in patients with OSA can be estimated using polysomnographic signals and may enable more personalized therapeutic interventions for patients with a low arousal threshold.
- Breath-holding as a means to estimate the loop gain contribution to obstructive sleep apnoea(2018) MESSINEO, Ludovico; TARANTO-MONTEMURRO, Luigi; AZARBARZIN, Ali; MARQUES, Melania D. Oliveira; CALIANESE, Nicole; WHITE, David P.; WELLMAN, Andrew; SANDS, Scott A.Increased ""loop gain"" of the ventilatory control system promotes obstructive sleep apnoea (OSA) in some patients and offers an avenue for more personalized treatment, yet diagnostic tools for directly measuring loop gain in the clinical setting are lacking. Here we test the hypothesis that elevated loop gain during sleep can be recognized using voluntary breath-hold manoeuvres during wakefulness. Twenty individuals (10 OSA, 10 controls) participated in a single overnight study with voluntary breath-holding manoeuvres performed during wakefulness. We assessed (1) maximal breath-hold duration, and (2) the ventilatory response to 20 s breath-holds. For comparison, gold standard loop gain values were obtained during non-rapid eye movement (non-REM) sleep using the ventilatory response to 20 s pulses of hypoxic-hypercapnic gas (6% CO2-14% O-2, mimicking apnoea). Continuous positive airway pressure (CPAP) was used to maintain airway patency during sleep. Additional measurements included gold standard loop gain measurement during wakefulness and steady-state loop gain measurement during sleep using CPAP dial-ups. Higher loop gain during sleep was associated with (1) a shorter maximal breath-hold duration (r(2) = 0.49, P < 0.001), and (2) a larger ventilatory response to 20 s breath-holds during wakefulness (second breath; r(2) = 0.50, P < 0.001); together these factors combine to predict high loop gain (receiver operating characteristic area-under-curve: 92%). Gold standard loop gain values were remarkably similar during wake and non-REM sleep. The results show that elevated loop gain during sleep can be identified using simple breath-holding manoeuvres performed during wakefulness. This may have implications for personalizing OSA treatment.
- Palatal prolapse as a signature of expiratory flow limitation and inspiratory palatal collapse in patients with obstructive sleep apnoea(2018) AZARBARZIN, Ali; SANDS, Scott A.; MARQUES, Melania; GENTA, Pedro R.; TARANTO-MONTEMURRO, Luigi; MESSINEO, Ludovico; WHITE, David P.; WELLMAN, AndrewIn some individuals with obstructive sleep apnoea (OSA), the palate prolapses into the velopharynx during expiration, limiting airflow through the nose or shunting it out of the mouth. We hypothesised that this phenomenon causes expiratory flow limitation (EFL) and is associated with inspiratory '' isolated '' palatal collapse. We also wanted to provide a robust noninvasive means to identify this mechanism of obstruction. Using natural sleep endoscopy, 1211 breaths from 22 OSA patients were scored as having or not having palatal prolapse. The patient-level site of collapse (tongue-related, isolated palate, pharyngeal lateral walls and epiglottis) was also characterised. EFL was quantified using expiratory resistance at maximal epiglottic pressure. A noninvasive EFL index (EFLI) was developed to detect the presence of palatal prolapse and EFL using the flow signal alone. In addition, the validity of using nasal pressure was assessed. A cut-off value of EFLI >0.8 detected the presence of palatal prolapse and EFL with an accuracy of >95% and 82%, respectively. The proportion of breaths with palatal prolapse predicted isolated inspiratory palatal collapse with 90% accuracy. This study demonstrates that expiratory palatal prolapse can be quantified noninvasively, is associated with EFL and predicts the presence of inspiratory isolated palatal collapse.