Psychiatric disorder does not preclude adequate continuous positive airway pressure titration.

Obstructive sleep apnea (OSA) is a highly prevalent disorder associated with significant morbidity and multiple complications. A large proportion of patients with OSA also have a coexisting primary psychiatric disorder. The effect of psychiatric disorders on the ability to tolerate continuous positive airway pressure (CPAP) titration is not known. In this study, whether the presence of psychiatric disorders precludes the patients' ability to tolerate CPAP titration for OSA was investigated. A retrospective chart review on a sample of 284 patients who underwent sleep studies in a single-center, university-based Veterans Affairs hospital was performed. A total of 143 patients with OSA who underwent titration of CPAP therapy were identified. The prevalence of psychiatric disorders between patients who tolerated titration and those who did not tolerate it was compared using the χ² test. The percentages of patients with psychiatric disorders who tolerated and did not tolerate CPAP were 33.6% and 33.3%, respectively. No statistically significant difference between the 2 groups (χ² = 0.051 with 1 degree of freedom; P = 0.82) was found. The predominantly male patient population, exclusion of mild OSA, lack of data about the level of control of the psychiatric symptoms and the sleep technicians not being blinded to the patients' psychiatric diagnoses were some of the limitations of this study. No significant difference existed in the prevalence of psychiatric disorders between patients intolerant to CPAP titration and those who tolerated CPAP for OSA.

Obstructive sleep apnea and immunity: relationship of lymphocyte count and apnea hypopnea index.

OBJECTIVES: The impact of chronic poor quality sleep on immunity as seen in obstructive sleep apnea (OSA) has not been evaluated. We aim to explore the relationship between lymphocytes, neutrophil, and total leukocyte counts with severity stratified apnea hypopnea index (AHI) in patients with OSA. METHODS: A retrospective review of 119 patients' medical records diagnosed with OSA from October 2005 to July 2006 was performed. Data collected included demographics, comorbidities, total leukocyte, neutrophil, and lymphocyte count, body mass index (BMI), AHI, and Epworth sleepiness scores (ESS). Three AHI strata were constructed: mild (5-14), moderate (15-29), and severe (>30). Data were fitted in a linear regression model on which lymphocyte counts were the dependent variable against age, BMI, and AHI. An interaction product was also explored (age*BMI). All tests were two-sided; a P < 0.05 was considered statistically significant. We used Statview Version 5.01 (SAS Institute, Inc., Cary, NC) for the analysis. RESULTS: Our study showed a linear association among AHI and BMI (P = 0.0017), but did not show association between lymphocyte count with either BMI (P = 0.33) or AHI (P = 0.90). A negative association between lymphocytes and age (P = 0.02) that persisted after adjustments for BMI and AHI was found. An interaction product (age*AHI) was not associated with lymphocyte count (P = 0.87). No correlation was found between peripheral blood count (P = 0.29) or neutrophil counts (P = 0.38) and AHI. CONCLUSION: We found OSA-induced sleep interruption not associated with lymphocyte, neutrophil, or peripheral blood cell count alterations. This information is useful for researchers evaluating the influence of sleep disruption on immunity.

Predictors of nocturnal oxygen desaturation in pulmonary arterial hypertension.

BACKGROUND: Sleep may be associated with significant respiratory compromise in patients with lung disease and can result in hypoxia. In patients with pulmonary arterial hypertension (PAH), nocturnal desaturation may not be reflected in daytime evaluations of oxygenation and can lead to worsening pulmonary hemodynamics. The study was conducted to determine the prevalence and significance of nocturnal oxygen desaturation in patients with PAH. METHODS: A cross-sectional study conducted at the Cleveland Clinic. Patients were followed up at our institution except for the overnight oximetry study done at home. Data regarding degree of nocturnal desaturation, demographics, hemodynamics, pulmonary function, and functional capacity were collected. RESULTS: Forty-three patients (mean age, 47.9 +/- 13.5 years [+/- SD]; 36 women and 7 men) underwent nocturnal oximetry. The etiology of PAH included idiopathic PAH (88%) and PAH associated with connective tissue diseases (12%). The majority of patients were New York Heart Association functional class II (42%) or III (53%). Thirty patients (69.7%) spent > 10% of sleep time with oxygen saturation by pulse oximetry < 90%. Desaturators were older (p = 0.024) and had higher hemoglobin (p = 0.002). Sixteen of 27 patients (59%) without desaturation < 90% during a 6-min walk test were nocturnal desaturators. Nocturnal desaturators had higher brain natriuretic protein (p = 0.004), lower cardiac index (p = 0.03), and higher mean right atrial pressure (p = 0.09), mean pulmonary artery pressure, and pulmonary vascular resistance. On echocardiography, desaturators were more likely to have moderate or severe right ventricular dilation (p = 0.04) and pericardial effusion. Only one patient had significant sleep apnea. CONCLUSIONS: Nocturnal hypoxemia is common in PAH patients and correlates with advanced pulmonary hypertension and right ventricular dysfunction. Approximately 60% patients without exertional hypoxia had nocturnal desaturation. Overnight oximetry should be considered in the routine workup of PAH patients who do not demonstrate exertional desaturation.

Clinical epidemiology of acute lung injury and acute respiratory distress syndrome: incidence, diagnosis, and outcomes.

Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) are clinical syndromes characterized by the sudden onset of severe hypoxemia and diffuse bilateral pulmonary infiltrates in the absence of left atrial hypertension. Although advances have been made in the understanding of the etiology, pathophysiology, and epidemiology of both entities, many questions remain regarding their incidence, diagnosis, and outcomes. This article reviews the currently used definition of ARDS and ALI, different studies that have advanced the understanding of the epidemiology and outcomes of these entities, and several diagnostic issues that are important for both clinicians and researchers.

Restless legs syndrome: keys to recognition and treatment.

Restless legs syndrome (RLS) is a common and clinically significant motor disorder increasingly recognized by physicians and the general public, yet still underdiagnosed, underreported, and undertreated. Effective therapies are available, but a high index of suspicion is required to make the diagnosis and start treatment quickly. We now have enough data to support the use of dopaminergic agents, benzodiazepines, antiepileptics, and opioids in these patients.

Ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication that is associated with modern techniques for in vitro fertilization. Extensive efforts have been made to understand the pathophysiology and to improve the management of this entity. The severe and life-threatening forms of the ovarian hyperstimulation syndrome are still challenging for critical care physicians. This article reviews the pathogenesis, epidemiology, classification, clinical manifestations, and complications of these forms of OHSS. The different therapeutic options currently available are reviewed, and a stepwise approach for the management of these patients is provided.

A rational approach to the evaluation and treatment of the infected patient in the intensive care unit.

Critically ill patients are at increased risk of acquiring nosocomial infections. A thorough clinical evaluation and the selection of appropriate diagnostic techniques are important elements in the evaluation of these patients. Nonetheless, this selection process can be difficult because of the wide spectrum of disease that is seen in the ICU and the lack of standardized studies that have evaluated the different diagnostic methods that are available. Many different antimicrobials are available for the treatment of ICU-acquired infections. Most antimicrobial regimens have not been evaluated in large-scale, prospective, randomized trials. Until this information is available, the clinician must make an effort to be familiar with the different clinical and epidemiologic variables that can be used to stratify patients at the moment of selecting antimicrobial therapy. The information provided in this article, used in association with good clinical judgment, will help the critical care physician provide optimal initial management of the infected patient in the ICU.