An official American Thoracic Society statement: continuous positive airway pressure adherence tracking systems. The optimal monitoring strategies and outcome measures in adults.

BACKGROUND: Continuous positive airway pressure (CPAP) is considered the treatment of choice for obstructive sleep apnea (OSA), and studies have shown that there is a correlation between patient adherence and treatment outcomes. Newer CPAP machines can track adherence, hours of use, mask leak, and residual apnea-hypopnea index (AHI). Such data provide a strong platform to examine OSA outcomes in a chronic disease management model. However, there are no standards for capturing CPAP adherence data, scoring flow signals, or measuring mask leak, or for how clinicians should use these data. METHODS: American Thoracic Society (ATS) committee members were invited, based on their expertise in OSA and CPAP monitoring. Their conclusions were based on both empirical evidence identified by a comprehensive literature review and clinical experience. RESULTS: CPAP usage can be reliably determined from CPAP tracking systems, but the residual events (apnea/hypopnea) and leak data are not as easy to interpret as CPAP usage and the definitions of these parameters differ among CPAP manufacturers. Nonetheless, ends of the spectrum (very high or low values for residual events or mask leak) appear to be clinically meaningful. CONCLUSIONS: Providers need to understand how to interpret CPAP adherence tracking data. CPAP tracking systems are able to reliably track CPAP adherence. Nomenclature on the CPAP adherence tracking reports needs to be standardized between manufacturers and AHIFlow should be used to describe residual events. Studies should be performed examining the usefulness of the CPAP tracking systems and how these systems affect OSA outcomes.

Central sleep apnea in patients with congestive heart failure.

Central apnea during sleep represents a manifestation of breathing instability in many clinical conditions of varied etiologies. Central apnea is the result of transient cessation of ventilatory motor output, which represents that inhibitory influences favoring instability predominate over excitatory influence favoring stable breathing. This article will review the determinants of central apnea, the specific features of CHF-related central apnea, and outline a management approach.

War is the Enemy of Health. Pulmonary, Critical Care, and Sleep Medicine in War-Torn Syria.

The Syrian crisis, now in its fifth year, has created an unprecedented strain on health services and systems due to the protracted nature of the warfare, the targeting of medics and health care infrastructure, the exodus of physicians and nurses, the shortage of medical supplies and medications, and the disruption of medical education and training. Within a few short years, the life expectancy of resident Syrians has declined by 20 years. Over the first 4 years of the conflict, more than 75,000 civilians died from injuries incurred in the violence. More than twice as many civilians, including many women and children, have died prematurely of infectious and noninfectious chronic diseases for want of adequate health care. Doctors, local administrators, and nongovernmental organizations are struggling to manage the consequences of the conflict under substandard conditions, often using unorthodox methods of health care delivery in field hospitals and remotely by telehealth communication. Much-needed medical supplies are channeled through dangerous routes across the borders from Lebanon, Jordan, and Turkey. Physicians in the United States and other western nations have helped Syrian physicians make the most of the situation by providing training on introducing innovations in technology and treatment. Portable ultrasound machines have been introduced and are being used extensively in the management of trauma and shock. This report, prepared by members of the Syrian American Medical Society, documents current needs for health care relief within Syria, focusing on pulmonary, critical care, and sleep medicine, and some of the efforts currently underway to meet those needs.

Pulmonary Hypertension an Independent Risk Factor for Death in Intensive Care Unit: Correlation of Hemodynamic Factors with Mortality.

OBJECTIVE: Critically ill patients with pulmonary hypertension (PH) pose additional challenges due to the existence of right ventricular (RV) dysfunction. The purpose of this study was to assess the impact of hemodynamic factors on the outcome. METHODS: We reviewed the records of patients with a diagnosis of PH admitted to the intensive care unit. In addition to evaluating traditional hemodynamic parameters, we defined severe PH as right atrial pressure >20 mmHg, mean pulmonary artery pressure >55 mmHg, or cardiac index (CI) <2 L/min/m(2). We also defined the RV functional index (RFI) as pulmonary artery systolic pressure (PASP) adjusted for CI as PASP/CI; increasing values reflect RV dysfunction. RESULTS: Fifty-three patients (mean age 60 years, 72% women, 79% Blacks), were included in the study. Severe PH was present in 68% of patients who had higher Sequential Organ Failure Assessment (SOFA) score (6.8 ± 3.3 vs 3.8 ± 1.6; P = 0.001) and overall in-hospital mortality (36% vs 6%; P = 0.02) compared to nonsevere patients, although Acute Physiology and Chronic Health Evaluation (APACHE) II scores (19.9 ± 7.5 vs 18.5 ± 6.04; P = 0.52) were similar and sepsis was more frequent among nonsevere PH patients (31 vs 64%; P = 0.02). Severe PH (P = 0.04), lower mean arterial pressure (P = 0.04), and CI (P = 0.01); need for invasive ventilation (P = 0.02) and vasopressors (P = 0.03); and higher SOFA (P = 0.001), APACHE II (P = 0.03), pulmonary vascular resistance index (PVRI) (P = 0.01), and RFI (P = 0.004) were associated with increased mortality. In a multivariate model, SOFA [OR = 1.45, 95% confidence interval (C.I.) = 1.09-1.93; P = 0.01], PVRI (OR = 1.12, 95% C.I. = 1.02-1.24; P = 0.02), and increasing RFI (OR = 1.06, 95% C.I. = 1.01-1.11; P = 0.01) were independently associated with mortality. CONCLUSION: PH is an independent risk factor for mortality in critically ill patients. Composite factors rather than individual hemodynamic parameters are better predictors of outcome. Monitoring of RV function using composite hemodynamic factors resulting in specific interventions is likely to improve survival and needs to be studied further.

Randomized controlled withdrawal study of upper airway stimulation on OSA: short- and long-term effect.

OBJECTIVE: To assess the efficacy and durability of upper airway stimulation via the hypoglossal nerve on obstructive sleep apnea (OSA) severity including objective and subjective clinical outcome measures. STUDY DESIGN: A randomized controlled therapy withdrawal study. SETTING: Industry-supported multicenter academic and clinical setting. SUBJECTS: A consecutive cohort of 46 responders at 12 months from a prospective phase III trial of 126 implanted participants. METHODS: Participants were randomized to either therapy maintenance ("ON") group or therapy withdrawal ("OFF") group for a minimum of 1 week. Short-term withdrawal effect as well as durability at 18 months of primary (apnea hypopnea index and oxygen desaturation index) and secondary outcomes (arousal index, oxygen desaturation metrics, Epworth Sleepiness Scale, Functional Outcomes of Sleep Questionnaire, snoring, and blood pressure) were assessed. RESULTS: Both therapy withdrawal group and maintenance group demonstrated significant improvements in outcomes at 12 months compared to study baseline. In the randomized assessment, therapy withdrawal group returned to baseline, and therapy maintenance group demonstrated no change. At 18 months with therapy on in both groups, all objective respiratory and subjective outcome measures showed sustained improvement similar to those observed at 12 months. CONCLUSION: Withdrawal of therapeutic upper airway stimulation results in worsening of both objective and subjective measures of sleep and breathing, which when resumed results in sustained effect at 18 months. Reduction of obstructive sleep apnea severity and improvement of quality of life were attributed directly to the effects of the electrical stimulation of the hypoglossal nerve.

Lateral oropharyngeal wall and supraglottic airway collapse associated with failure in sleep apnea surgery.

OBJECTIVES/HYPOTHESIS: To identify patterns of airway collapse during preoperative drug-induced sleep endoscopy (DISE) as predictors of surgical failure following multilevel airway surgery for patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). STUDY DESIGN: Retrospective clinical chart review. METHODS: Medical records of patients who underwent site-specific surgical modification of the upper airway for treatment of OSHAS were reviewed. Patients were included in this study if they had a preoperative airway evaluation with DISE as well as preoperative and postoperative polysomnography. Airway obstruction on DISE was described according to airway level, severity, and axis of collapse. Severe airway obstruction was defined as >75% collapse on endoscopy. Surgical success was described as a postoperative apnea-hypopnea index (AHI) of <20 and a >50% decrease in preoperative AHI. RESULTS: A total of 34 patients were included in this study. The overall surgical success rate was 56%. Surgical success (n = 19) and surgical failure (n = 15) patients were similar with regard to age, gender, body mass index, preoperative AHI, Friedman stage, adenotonsillar grades, and surgical management. DISE findings in the surgical failure group demonstrated greater incidence of severe lateral oropharyngeal wall collapse (73.3% vs. 36.8%, P = .037) and severe supraglottic collapse (93.3% vs. 63.2%, P = .046) as compared to the surgical success group. CONCLUSIONS: The presence of severe lateral pharyngeal wall and/or supraglottic collapse on preoperative DISE is associated with OSAHS surgical failure. The identification of this failure-prone collapse pattern may be useful in preoperative patient counseling as well as in directing an individualized and customized approach to the treatment of OSHAS.