الفهرس 
Oxygen therapyOnly 14 pages are availabe for public view
 |  | from | 108 |  |  |
| | | from | 108 | | |
Abstract
Oxygen is a vital element in human survival and plays a major role in a diverse range of biological and physiological processes. In medical practice, it is among the most universally used agents for the treatment of critical illness and part of the routine treatment in acute shock and emergency medicine). While avoiding hypoxemia has long been a goal of critical care practitioners, oxygen therapy during mechanical ventilation, anesthesia, and resuscitation usually exceeds physiological level and less attention has been paid to the potential for excessive oxygenation. Hyperoxia is a state of excess supply of O2 in tissues and Organs. Oxygen toxicity occurs when the partial pressure of alveolar O2 (PAO2) exceeds that which is breathed under normal conditions. With continuous exposure to supra physiologic concentrations of O2, a state of hyperoxia develops. In recent years, there has been mounting evidence demonstrating the potential adverse effects of hyperoxia on the cardiovascular system. Also, it has been long appreciated that hyperoxia has adverse consequences in patients with chronic obstructive lung disease or acute respiratory failure, as gas exchange may be worsened by de-nitrogenation atelectasis and increased intrapulmonary shunting. In the post-resuscitation phase, there is evidence that patients surviving initial resuscitation may be managed more safely with 30% oxygen than with 100% oxygen. Clinically, hyperoxia is associated with poor neurological outcome following resuscitation.