Prone Position on Oxygenation in the Patient with Acute Respiratory Distress Syndrome after Decortication with Bilateral Empyectomy / 대한마취과학회지

The effects of the prone position on the improvement of oxygenation in patients with ARDS were reported already twenty years ago. Recent studies have shown that the prone position would improve the ventilation and perfusion relationship as it improves the ventilation in the local area without altering the pulmonary blood flow during the support of ventilation in the patients with ARDS. We have applied the prone position repeatly on the patient with ARDS which developed after the removal of a bilateral pulmonary empyema and decortication. The initial effect of the prone position on oxygenation improved the PaO2/FiO2 (arterial oxygen tension divided by inspired oxygen concentration) ratio, 104.3 to 132.9, at FiO2 0.7. Improvement of oxygenation was maintained with repeat position change, three times over 24 hours, from supine to prone position.

Epithelial Modulation on Guinea-pig Tracheal Smooth Muscle Tension to Contractile Agents / 대한마취과학회지

BACKGROUND: Asthma can be described as the hypersensitivity of the airway to various stimuli. Injury to tracheal epithelial cells could be the reason for tracheal hypersensitivity in asthma or upper respiratory infection. This study is based on the hypothesis that the dysfunction of the airway in asthma is caused by epithelial cell injury. METHODS: After isolating guinea-pig tracheal preparations, in order to examine the role of airway epithelium in response to smooth muscle, we measured the contractile responses to acetylcholine, carbachol, and histamine on the isolated epithelium-denuded or epithelium-intact guinea-pig tracheal preparations. When tracheal tones were stabilized, each contractile agent was added cumulatively to the organ baths to obtain concentration-response curves, and ED50 and ED95 were calculated. RESULTS: In both groups, tracheal tones increased in response to contractile agents, in concentration- dependent manners. In comparing both groups, the contractility of denuded trachea was increased by 10 7 and 10 6 M in acetylcholine, and by 10 6 M in histamine significantly. In denuded trachea, ED50 and ED95 increased significantly in response to both acetylcholine and histamine. However, they did not increase in carbachol. CONCLUSIONS: The removal of the epithelium increased the contractile responses to acetylcholine and histamine.

The Effect of Norepinephrine on Blood Pressure and Blood Flow of the Brachial and Femoral Arteries / 대한마취과학회지

BACKGROUND: Arterial pressure is the most commonly utilized guideline for the management of critically ill patients. However, the site of arterial pressure monitoring can impact the observed pressure. In patients undergoing cardiac surgery, peripheral arterial pressure can underestimate central aortic pressure and vasodilators magnify this phenomenon. There was also a large discrepancy between radial and femoral artery pressure in endotoxemic patients treated with vasopressors or hypothermic patients. We evaluated the effect of the continuous infusion of norepinephrine, the most commonly used vasopressor, on pressure and blood flow in both the brachial and femoral artery in dogs in normal condition. METHODS: Both the brachial and femoral arteries were cannulated for pressure monitoring and the other side arteries were exposed for the measurement of blood flow in 10 dogs. Two doses of norepinephrine (NE), 0.05 microgram/kg/min and 0.1 microgram/kg/min, were infused for 10 minutes each in sequence. Hemodynamic variables and blood flow were measured before the infusion of NE, and immediately after the infusion of the two doses of NE. RESULTS: NE increased both brachial and femoral arterial pressures with no difference between the two pressures. NE decreased blood flow in both brachial and femoral arteries even though cardiac output was maintained constantly which means NE caused the redistribution of blood flow. CONCLUSIONS: Unlike endotoxemic shock conditions or hypothermic vasoconstriction, NE didn't show different effects on pressure monitoring sites regardless of their diameter in normal condition. NE increased blood pressure and decreased blood flow in the same degree in both the brachial and femoral artery.