INTRODUCTION Most decompression procedures induce the formation of asymptomatic venous gas bubbles. They can be classified as "silent bubbles," which are asymptomatic compared to paradoxical arterialization of venous gas emboli, which can lead to serious neurologic damage. The penetration of such gas bubbles into the arterial circulation is due to pulmonary barotrauma, intrapulmonary (I-P) pass...

The first description of pulmonary arteriovenous malformations (PAVM) was made already in 1897 by Churton [1]. PAVM are abnormal vascular structures that connect the pulmonary arterial bed directly to the pulmonary venous bed, thereby bypassing the pulmonary capillaries and resulting in an intrapulmonary shunt which, depending on number and size of the PAVM, may result in arterial desaturation ...

We wished to study the effect of airways secretion on gas exchange. Peripheral airway secretion was simulated in 9 rabbits by the continuous inhalation of nebulized isotonic saline, at a droplet size of about 3 microns. Intrapulmonary deposition of saline in the peripheral airways (83% in airways smaller than 0.5 mm) did not alter total inspiratory resistance (mean 5.4 kPa.l-1.s), but led to a ...

The effects of sildenafil (Viagra) on hemodynamics and pulmonary gas exchange remain uncertain. The aim of this study was to investigate what effect sildenafil had on gas exchange. A total of 24 anesthetized pigs were randomly assigned into four groups of six animals each: Group Low received 25 mg of sildenafil, which is equivalent to half the recommended dose for humans; group Normal received ...

Eight patients with severe bronchopulmonary dysplasia underwent cardiac catheterisation. Seven had a pulmonary vascular resistance greater than 3 mm Hg.l-1 min.m2 (mean 8.9, range 2.2-13.8). All had raised intrapulmonary shunts (mean 25.6%, range 5.4-50%, normal less than 5%). Two had a high alveolar dead space, and two had unsuspected congenital heart disease. Epoprostenol (prostacyclin), but ...

Background. Inhalation of nitric oxide (NO) causes selective pulmonary vasodilation and improves arterial oxygenation in acute respiratory distress syndrome. But some patients do not respond or gas exchange worsens when inhaling NO. We hypothesised that this detrimental effect might be related to the reversion of hypoxic vasconstriction in those patients where this mechanism contributes to vent...

Ventilation-perfusion relationships were studied in patients with non-alcoholic liver cirrhosis. Spirometry was essentially normal but the transfer factor of the lung (DLCO) was reduced by an average 34% of predicted. Arterial oxygen tension (PaO2) ranged from normal down to 6.9 kPa. Varying degrees of ventilation-perfusion (VA/Q) abnormalities (multiple inert gas elimination technique) were ob...

We have studied arterial oxygen saturation (SaO2), breathing patterns, and electroencephalographic (EEG) sleep stage during nocturnal sleep in six patients with right-to-left cardiac or intrapulmonary shunts and six patients with chronic bronchitis and emphysema, chosen because they were equally hypoxaemic when awake (SaO2 during wakefulness: bronchitis 74-90%, mean 83%; shunt 77-89%, mean 83%)...

To facilitate the work of the thoracic surgeon it has become accepted procedure in certain circumstances to collapse the diseased lung being operated upon. To accomplish this, the technique most frequently used by the anaesthetist calls for the insertion of a double lumen endobronchial tube. This makes it possible to isolate the intact dependent lung from the diseased upper one and thus to prev...