Negative-pressure pulmonary edema accompanied by hemorrhage as a manifestation of upper airway obstruction is an uncommon problem that is potentially life-threatening. The principal pathophysiological mechanism involved is the generation of markedly negative intrathoracic pressure, which leads to an increase in pulmonary vascular volume and pulmonary capillary transmural pressure, creating a risk of disruption of the alveolar-capillary membrane. We report the case of an adult male with diffuse alveolar hemorrhage following acute upper airway obstruction caused by the formation of a cervical and mediastinal abscess resulting from the insertion of a metallic tracheal stent. The patient was treated through drainage of the abscess, antibiotic therapy, and positive pressure mechanical ventilation. This article emphasizes the importance of including this entity in the differential diagnosis of acute lung injury after procedures involving upper airway instrumentation.

Keywords: Hemorrhage; Pulmonary edema; Airway obstruction; Abscess; Prostheses and implants.

Alveolar hemorrhage leading to respiratory failure is uncommon. Various etiologies have been reported, including systemic lupus erythematosus, which generally presents as pulmonary-renal syndrome. It is believed that the pathogenesis of microangiopathy is related to deposits of immune complexes that lead to activation of cellular apoptosis. The authors report two cases of alveolar hemorrhage and respiratory failure, both requiring mechanical ventilation. The two cases had opposite outcomes after pharmacological therapy. The presence of anti-glomerular basement membrane antibodies in one of the cases demonstrates the multiplicity of physiopathological mechanisms that may be involved. This multiplicity of mechanisms provides a possible explanation for the heterogeneous responses to the available treatments.

Keywords: Lupus erythematosus systemic/etiology. Lupus nephritis/etiology. Respiratory insufficiency/complications.

Objective: To investigate the effects of airway obstruction on albuterol-mediated variations in the resistive and elastic properties of the respiratory system of adult patients with asthma. Methods: This study comprised 24 healthy controls and 69 patients with asthma, all of whom were nonsmokers. The patients were divided into three groups according to the severity of airway obstruction (mild, moderate or severe). Each of the three groups was divided into two subgroups according to the bronchodilator response (BR): positive (BR+) or negative (BR−). These measurements were conducted before and after albuterol use (300 µg). Airway obstruction was determined by means of spirometry, and the resistive and elastic properties were determined by means of the forced oscillation technique. Results: The resistance at the intercept (R0) presented greater reductions in the groups with higher obstruction. This reduction was more evident in the BR+ subgroups than in the BR− subgroups (p < 0.02 and p < 0.03, respectively). There was a significant difference between the control group and the BR+ subgroup with severe obstruction (p < 0.002). The reductions in dynamic elastance (Edyn) were significantly greater in proportion to the degree of obstruction, in the BR− subgroups (p < 0.03), and in the BR+ subgroups (p < 0.003). The reductions in Edyn were significantly greater in the BR− subgroup with moderate obstruction (p < 0.008) and in the BR+ subgroup with severe obstruction (p < 0.0005) than in the control group. Conclusions: In patients with asthma, increased airway obstruction results in greater reductions in R0 and Edyn after albuterol use. These reductions are greater among BR+ patients than among BR− patients.

Keywords: Asthma; Bronchodilator agents; Respiratory mechanics; Spirometry; Albuterol.

Objective: The identification of persistent airway obstruction is key to making a diagnosis of COPD. The GOLD guidelines suggest a fixed criterion-a post-bronchodilator FEV1/FVC ratio < 70%-to define obstruction, although other guidelines suggest that a post-bronchodilator FEV1/FVC ratio < the lower limit of normal (LLN) is the most accurate criterion. Methods: This was an observational study of individuals = 40 years of age with risk factors for COPD who were referred to our pulmonary function laboratory for spirometry. Respiratory symptoms were also recorded. We calculated the prevalence of airway obstruction and of no airway obstruction, according to the GOLD criterion (GOLD+ and GOLD-, respectively) and according to the LLN criterion (LLN+ and LLN-, respectively). We also evaluated the level of agreement between the two criteria. Results: A total of 241 individuals were included. Airway obstruction was identified according to the GOLD criterion in 42 individuals (17.4%) and according to the LLN criterion in 23 (9.5%). The overall level of agreement between the two criteria was good (? = 0.67; 95% CI: 0.52-0.81), although it was lower among the individuals = 70 years of age (? = 0.42; 95% CI: 0.12-0.72). The proportion of obese individuals was lower in the GOLD+/LLN+ category than in the GOLD+/LLN- category (p = 0.03), as was the median DLCO (p = 0.04). Conclusions: The use of the GOLD criterion appears to be associated with a higher prevalence of COPD. The agreement between the GOLD and LLN criteria also appears to be good, albeit weaker in older individuals. The use of different criteria to define airway obstruction seems to identify individuals with different characteristics. It is essential to understand the clinical meaning of discordance between such criteria. Until more data are available, we recommend a holistic, individualized approach to, as well as close follow-up of, patients with discordant results for airway obstruction.

Keywords: Pulmonary disease, chronic obstructive; Airway obstruction; Spirometry.

Objective: To determine whether airway narrowing during obstructive events occurs predominantly at the retropalatal level and results from dynamic changes in the lateral pharyngeal walls and in tongue position. Methods: We evaluated 11 patients with severe obstructive sleep apnea (OSA) and 7 healthy controls without OSA during wakefulness and during natural sleep (documented by full polysomnography). Using fast multidetector CT, we obtained images of the upper airway in the waking and sleep states. Results: Upper airway narrowing during sleep was significantly greater at the retropalatal level than at the retroglossal level in the OSA group (p < 0.001) and in the control group (p < 0.05). The retropalatal airway volume was smaller in the OSA group than in the control group during wakefulness (p < 0.05) and decreased significantly from wakefulness to sleep only among the OSA group subjects. Retropalatal pharyngeal narrowing was attributed to reductions in the anteroposterior diameter (p = 0.001) and lateral diameter (p = 0.006), which correlated with an increase in lateral pharyngeal wall volume (p = 0.001) and posterior displacement of the tongue (p = 0.001), respectively. Retroglossal pharyngeal narrowing during sleep did not occur in the OSA group subjects. Conclusions: In patients with OSA, upper airway narrowing during sleep occurs predominantly at the retropalatal level, affecting the anteroposterior and lateral dimensions, being associated with lateral pharyngeal wall enlargement and posterior tongue displacement.

Keywords: Multidetector computed tomography; Oropharynx; Sleep apnea, obstructive; Polysomnography; Diagnostic imaging; Sleep.

Reexpansion pulmonary edema (RPE) is a rare, but frequently lethal, clinical entity. The precise pathophysiologic abnormalities associated with this disorder are still unknown: decreased surfactant levels and a pro-inflammatory status are putative mechanisms. Early diagnosis is crucial, since prognosis depends on early recognition and prompt treatment. Considering the high mortality rates related to RPE, preventive measures are still the best available strategy for patient handling. This review provides a brief overview of the pathophysiology, diagnosis, treatment, and prevention of RPE, with practical recommendations for adequate intervention.

Although pneumonectomy is a technically simple procedure, it has been associated with a high (60%) incidence of complications. Respiratory complications account for approximately 15% of such complications. Worldwide, the mortality rate among patients subjected to pneumonectomy is 8.6%. However, the rate among patients developing respiratory complications is 30%. Although postpneumonectomy pulmonary edema is rare (occurring in 3% to 5% of cases), it is a serious complication and is almost always fatal. It was first described twenty years ago and, despite these alarming statistics, little is known regarding the physiopathology of postpneumonectomy pulmonary edema. Once it has become entrenched, the condition is difficult to treat, and there is no proven efficient treatment. Various risk factors have been correlated with postpneumonectomy pulmonary edema onset. Fluid overload was the first to be identified as a factor to avoid. However, many studies have shown that there is no direct correlation between fluid overload and the development of edema. Prevention is the best way to avoid postpneumonectomy pulmonary edema and must be performed in a multidisciplinary fashion, involving the entire medical staff - from the initiation of anesthesia through the surgical procedure and extending into the critical care management phase. Equally important is early identification and testing of patients at risk for postpneumonectomy pulmonary edema when there is clinical suspicion of this serious complication.

Keywords: Key Words: Pulmonary edema/complications. Pneumonectomy/adverse effects. Risk factors. Pulmonary edema/prevention & control.

Objective: Obstructive sleep apnea syndrome (OSAS) has a high prevalence and carries significant cardiovascular risks. It is important to study new therapeutic approaches to this disease. Positional therapy might be beneficial in reducing the apnea-hypopnea index (AHI). Imaging methods have been employed in order to facilitate the evaluation of the airways of OSAS patients and can be used in order to determine the effectiveness of certain treatments. This study was aimed at determining the influence that upper airway volume, as measured by cervical CT, has in patients diagnosed with OSAS. Methods: This was a quantitative, observational, cross-sectional study. We evaluated 10 patients who had been diagnosed with OSAS by polysomnography and on the basis of the clinical evaluation. All of the patients underwent conventional cervical CT in the supine position. Scans were obtained with the head of the patient in two positions (neutral and at a 44° upward inclination), and the upper airway volume was compared between the two. Results: The mean age, BMI, and neck circumference were 48.9 ± 14.4 years, 30.5 ± 3.5 kg/m2, and 40.3 ± 3.4 cm, respectively. The mean AHI was 13.7 ± 10.6 events/h (range, 6.0-41.6 events/h). The OSAS was classified as mild, moderate, and severe in 70%, 20%, and 10% of the patients, respectively. The mean upper airway volume was 7.9 cm3 greater when the head was at a 44° upward inclination than when it was in the neutral position, and that difference (17.5 ± 11.0%) was statistically significant (p = 0.002). Conclusions: Elevating the head appears to result in a significant increase in the caliber of the upper airways in OSAS patients.

Keywords: Sleep apnea, obstructive/prevention and control; Sleep apnea, obstructive/therapy; Tomography.

Objective: This study aimed to use high-resolution computed tomography scans of the chest to characterize the principal alterations occurring in cases of hydrostatic pulmonary edema. Methods: A retrospective analysis was made of the tomography scans of 15 patients presenting clinical profiles of hydrostatic pulmonary edema. The cases were divided into five groups by etiology: congestive heart failure (n = 7); acute mitral valve disease (n = 2); acute myocardial infarction (n = 2); myocarditis (n = 2); and fibrosing mediastinitis (n = 2). Results: The principal findings in the cases of hydrostatic pulmonary edema were ground-glass opacities (in 100%), interlobular septal thickening (in 100%), pleural effusion (in 87%) and peribronchovascular interstitial thickening (in 80%). Other, less common, findings were increased blood vessel diameter, consolidations and air-space nodules. Conclusion: The predominant pattern found in the patients studied was that of ground-glass opacities accompanied by interlobular septal thickening (mosaic attenuation pattern) and bilateral (predominantly right-sided) pleural effusion.

Keywords: Pulmonary edema; Tomography, X-ray computed; Lung diseases

Objective: To investigate the presence of airway obstruction by determining the FEV1/FVC and FEV1/slow vital capacity (SVC) ratios. Methods: This was a quantitative, retrospective cross-sectional study. The sample comprised 1,084 individuals who underwent spirometry and plethysmography in a central hospital in Lisbon, Portugal. The study sample was stratified into six groups, by pulmonary function. Results: The analysis of the FEV1/FVC ratio revealed the presence of airway obstruction in 476 individuals (43.9%), compared with 566 individuals (52.2%) for the analysis of the FEV1/SVC ratio. In the airway obstruction, airway obstruction plus lung hyperinflation, and mixed pattern groups, the difference between SVC and FVC (SVC − FVC) was statistically superior to that in the normal pulmonary function, reduced FEF, and restrictive lung disease groups. The SVC − FVC parameter showed a significant negative correlation with FEV1 (in % of the predicted value) only in the airway obstruction plus lung hyperinflation group. Conclusions: The FEV1/SVC ratio detected the presence of airway obstruction in more individuals than did the FEV1/FVC ratio; that is, the FEV1/SVC ratio is more reliable than is the FEV1/FVC ratio in the detection of obstructive pulmonary disease.

Keywords: Airway Obstruction; Spirometry; Plethysmography.

Objective: To assess the sensitivity and specificity of flow-volume curves in detecting central airway obstruction (CAO), and to determine whether their quantitative and qualitative criteria are associated with the location, type and degree of obstruction. Methods: Over a four-month period, we consecutively evaluated patients with bronchoscopy indicated. Over a one-week period, all patients underwent clinical evaluation, flow-volume curve, bronchoscopy, and completed a dyspnea scale. Four reviewers, blinded to quantitative and clinical data, and bronchoscopy results, classified the morphology of the curves. A fifth reviewer determined the morphological criteria, as well as the quantitative criteria. Results: We studied 82 patients, 36 (44%) of whom had CAO. The sensitivity and specificity of the flow-volume curves in detecting CAO were, respectively, 88.9% and 91.3% (quantitative criteria) and 30.6% and 93.5% (qualitative criteria). The most prevalent quantitative criteria in our sample were FEF50%/FIF50% ≥ 1, in 83% of patients, and FEV1/PEF ≥ 8 mL . L−1 . min−1, in 36%, both being associated with the type, location, and degree of obstruction (p < 0.05). There was concordance among the reviewers as to the presence of CAO. There is a relationship between the degree of obstruction and dyspnea. Conclusions: The quantitative criteria should always be calculated for flow-volume curves in order to detect CAO, because of the low sensitivity of the qualitative criteria. Both FEF50%/FIF50% ≥ 1 and FEV1/PEF ≥ 8 mL . L−1 . min−1 were associated with the location, type and degree of obstruction.

Keywords: Bronchoscopy; Maximal expiratory flow-volume curves; Sensitivity and specificity; Lung neoplasms.

Patients with severe asthma and blunted perception of their bronchial obstruction are likely to have elevated risk of death from asthma. The authors describe the case of a 52-year-old woman with asthma whose test results, in a prospective study for the identification of patients with blunted perception of the intensity of their own bronchial obstruction, showed the minimum score in the analogic visual scale in the presence of reduced morning FEV1 and EFP. After the study, the patient was seen at the outpatient clinic. He had no complaints, seemed normal at physical examination and reported to be using no medication at all. Then, while still in the clinic, he suddenly developed dyspnea, respiratory failure, and non-revertible cardio-respiratory failure. Blunted perception of the bronchial obstruction severity probably contributed to the development of acute respiratory failure and death of the patient.

Keywords: Dyspnea. Asthma. Bronchial spasm. Death. Perception.

Objective: To investigate the efficacy of upper limb exercise training (ULExT) in improving the performance of activities of daily living (ADL) that involve the upper limbs (UL) in patients with COPD. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used in this systematic review. PubMed and EBSCOhost databases were searched to identify randomized controlled trials involving adults with COPD who underwent ULExT, compared with those who underwent other types of exercise or no exercise, in order to assess the performance of ADL that involve the UL. The methodological quality of the selected studies was assessed using the Physiotherapy Evidence Database scale. Results: Five studies, with a total sample of 173 subjects, met the inclusion criteria. The results of the selected studies showed that ULExT is safe and can significantly improve the performance of ADL that involve the UL in patients with COPD. However, there were inconsistencies in the results, especially regarding the perception of symptoms during ADL. The small number of studies included and their methodological quality do not allow for firm conclusions. Conclusions: The findings of this review revealed that ULExT is a safe therapeutic approach and can improve the performance of ADL that involve the UL in patients with COPD, but the results are unclear. Further investigation through well-designed randomized trials is warranted to determine the effectiveness of ULExT in improving the performance of ADL that involve the UL in patients with COPD.

Keywords: Upper extremity; Pulmonary disease, chronic obstructive; Activities of daily living, Exercise therapy.