Comparison of four demand oxygen delivery systems at rest and during exercise for chronic obstructive pulmonary disease.

Objectives: The aim of this study was to assess the performance of four demand oxygen delivery systems (DODS) in improving oxygenation and effort tolerance, at rest and during exercise, in chronic obstructive pulmonary disease (COPD) patients.

Materials And Methods: Thirteen COPD patients were prospectively included. Four DODS (Oxiclip, Versatile, Venture and Impulse) were compared with continuous-flow oxygen (CFO).

Use of glass capillaries avoids the time changes in high blood PO(2) observed with plastic syringes.

Study Objectives: In adults, arterial blood samples are usually drawn using plastic syringes. In contrast to glass syringes, plastic syringes let oxygen diffuse through their wall. This results in PO(2) changes during storage, especially when PO(2) is high.

Optimal handling of blood samples for routine measurement of lactate and pyruvate.

Blood lactate and pyruvate are of critical importance for the diagnosis of mitochondrial diseases. To determine guidelines for adequate blood pyruvate and lactate determinations, intraindividual studies were carried out on 10 subjects, and the influences of venostasis, delay before deproteinization, and pH in the pyruvate assay were analyzed. Delays of 1 hour or more before deproteinization of samples induced major elevations of lactate-pyruvate ratios.

Measurement of gastric intramucosal pH in patients with cirrhosis and portal hypertensive gastropathy.

Objectives: Patients with cirrhosis often have gastric mucosal lesions associated with portal hypertension. Microvascular changes due to portal hypertension may cause mucosal ischaemia. The decrease in intramucosal pH is used as an index of this condition.

Hemodynamic and gas exchange responses to infusion of acetylcholine and inhalation of nitric oxide in patients with chronic obstructive lung disease and pulmonary hypertension.

To investigate endothelium-dependent and endothelium-independent nitric oxide (NO) mediated pulmonary vasodilation in patients with chronic obstructive lung disease (COLD), we examined the responses to incremental infusion rates of acetylcholine (ACh) or inhaled NO on hemodynamic and gas exchange. In 13 patients, ACh (15 mg/min) decreased pulmonary artery pressure (Ppa) from 31 +/- 1 to 28 +/- 1 mm Hg (p < 0.01) and systemic arterial pressure while increasing cardiac index from 3.