Ventilatory mechanics and expiratory flow limitation during exercise in patients with obstructive lung disease.

The interrelationships among transpulmonary pressure, flow, and volume during exhausting exercise were studied in 12 males with chronic obstructive lung disease. Expiratory pressure during exercise was compared with flow-limiting pressure (P(max)) measured at rest. In 11 patients, expiratory pressure during exercise exceeded P(max), indicating that ventilation became mechanically inefficient. P(max) values of the patients were lower than those of normal subjects. Evidence of expiratory flow augmentation during exercise was noted in two subjects. Since 10 subjects achieved maximal expiratory flow predicted from flow-volume curves when heart rate was not maximal, we conclude that exercise capacity in most subjects was clearly limited by the deranged ventilatory apparatus. Elevations in mean intrathoracic pressure during exercise also may interfere with venous return and impose an additional limitation.

Shortcomings of using two jet nebulizers in tandem with an aerosol face mask for optimal oxygen therapy.

Herein, a laboratory model which allows measurement of simulated distal airway oxygen percentage at different breathing patterns is described to illustrate the shortcomings of conventional O2 devices and, in particular, the aerosol face mask with two jet nebulizers (AFM-DF) in tandem. A table showing the degree of dilution which occurred during simulation of various breathing patterns while using the AFM-DF is also presented. Data revealed that when 60 percent was desired, 13 of 27 measurements were less than 55 percent. The worst-case scenario for 60 percent desired was 48 percent measured. When 80 percent was desired, less than 70 percent was delivered in 24 of the 27 breathing patterns simulated. Less than 60 percent was measured on 12 occasions, with 51 percent being the lowest measurement. When 100 percent O2 was desired, less than 80 percent was measured in 25 of 27 breathing patterns. Less than 60 percent was measured in ten of those. Fifty percent was the lowest analyzed value for the 100 percent setting. The inadequacy of AFM-DF is described in three case studies. A high-flow nonrebreathing face mask (HFM) to address the subset of patients is also discussed. A peak inspiratory flow prediction chart is also documented and may be useful in setting optimal flows when using high-flow systems. The patients in whom intubation and mechanical ventilation (or use of continuous mask CPAP) are indicated can be more clearly identified with a trial of high-flow O2 therapy (with a system that assures adequate flow to meet the patient's peak inspiratory flow demands). In the remainder of patients, those higher-risk modalities will be precluded.

Stigma experiences in bipolar patients: the impact upon functioning.

The aim of this study was to investigate the impact of self-rated stigma and functioning in patients with bipolar disorder in South Brazil. This is a cross-sectional study. Sixty participants with bipolar disorder were recruited from an outpatient Bipolar Disorder Program. Experiences with and impact of perceived stigma were evaluated using the Inventory of Stigmatizing Experiences. Functional impairment was assessed with the Functioning Assessment Short Test (FAST). Higher scores of self-perceived stigma were correlated with higher FAST scores, indicating more disability. After linear correlation analysis, current depressive symptoms, age at onset of treatment, age at diagnosis and functioning were correlated with self-perceived stigma. The study demonstrated a correlation between stigma and poor functioning in bipolar disorder. Perceived stigma is really important to individuals with bipolar disorder, both to how they experience their illness and to its results on functioning. Potential consequences of such results for mental health care professionals are discussed. Differential clinical features, sociocultural factors and the sample size limit the generalization of the present findings.

Mass spectrometry for innovative techniques of respirator care, ventilator weaning and differential ventilation in an intensive care unit.

The medical mass spectrometry as a monitoring instrument in a respiratory intensive care unit (RICU) is described. Its uses, both routine and as a tool for innovative techniques in respiratory care, are many. As an adjunct to traditional and intermittent mandatory ventilation (IMV) weaning techniques, monitoring of expired respiratory gases can hasten the safe removal of patients from mechanical ventilators. A specialized technique of dealing with ventilating the lungs differentially when their mechanical properties differ is described to illustrate the versatility of the instrument. In critical care areas, monitoring of patients with respiratory problems should include continuous monitoring of end-tidal or expired CO2.