Introduction: Capnography, is an easy, fast and practical method which its application in the diagnosis of Pulmonary Thromboendarterectomy (PTE) has recently been studied. This study aimed to assess the diagnostic value of end-tidal CO2 (ETCO2) and the alveolar dead space (AVDS) in the diagnosis of patients suspected to PTE who have been referred to the emergency department. Materials and Metho...

To help students understand the concept of the ventilation-perfusion ratio (VA/Q) and the effects that VA/Q mismatching has on pulmonary gas exchange, a "sliding rectangles" visual aid was developed to teach VA/Q relationships. Adjacent rectangles representing "ventilation" and "perfusion" are slid past one another so that portions of the ventilation and perfusion rectangles are not touching, i...

Eight volunteers were exposed for eight hours to about 200 ppm of 1,1,1-trichloroethane. On the next morning five series of five alveolar samples were collected for the simultaneous determination of PCO2 and 1,1,1-trichloroethane concentration. Three different methods of sampling were used: voluntary hyperventilation, 10-s breathholding, and "standard." A linear relationship between the alveola...

The pulmonary circuit receives the whole of the cardiac output, and the flow through it is governed by events in the systemic circulation. Its function is gaseous exchange, and the low resistance and high capacitance of the circuit is subservient to this function. Local flow is affected by intra-alveolar oxygen tensions and regional flow by passive hydrostatic effects due to gravity. The distri...

Pulmonary function was examined in 19 young asthmatic patients at rest and during two levels of excercise. Findings at rest included decreased flow rates, increased residual volume, normal minute (VE) and alveolar (VA) ventilation, increased ratio of physiological dead space to tidal volume (VD/VT), increased alveolar-arterial oxygen tension difference (A-a PO2), and mild arterial hypoxaemia an...

BACKGROUND The purpose of this study was to compare the effects of 0.5 fraction of inspired oxygen (FiO₂) and >0.95 FiO₂ on pulmonary gas exchange, shunt fraction and oxygen delivery (DO₂) in dorsally recumbent horses during inhalant anesthesia. The use of 0.5 FiO₂ has the potential to reduce absorption atelectasis (compared to maximal FiO₂) and augment alveolar oxygen (O₂) tensions (compared t...

STUDY OBJECTIVE To compare the diagnostic performance of volumetric capnography (VCap), which is the plot of the expired CO(2) partial pressure against the expired volume during a single breath, with the PaCO(2) to end-tidal CO(2) (EtCO(2)) gradient, in the case of suspected pulmonary embolism (PE). DESIGN Single-center, prospective study. SETTING Emergency department of a teaching hospital...

BACKGROUND Passive humidifiers have gained acceptance in the intensive care unit because of their low cost, simple operation, and elimination of condensate from the breathing circuit. However, the additional dead space of these devices may adversely affect respiratory function in certain patients. This study evaluates the effects of passive humidifier dead space on respiratory function. METHO...