Ylihappiakumuloituminen

Ylihappiakumuloituminen, often translated as hyperoxia or oxygen toxicity, refers to the adverse effects of breathing excessive concentrations of oxygen for extended periods. While oxygen is essential for life, high partial pressures of oxygen can lead to cellular damage and dysfunction. This phenomenon is particularly relevant in medical contexts, such as mechanical ventilation, hyperbaric oxygen therapy, and in neonates where developing lungs are more susceptible.

The primary mechanism behind oxygen toxicity involves the overproduction of reactive oxygen species (ROS), also known as free radicals. These highly unstable molecules can damage cellular components like DNA, proteins, and lipids. The body has antioxidant defense systems to neutralize ROS, but when oxygen levels are excessively high, these systems can be overwhelmed. This imbalance leads to oxidative stress, causing inflammation and cell death.

Symptoms of oxygen toxicity vary depending on the concentration of oxygen and the duration of exposure. In the lungs, it can manifest as substernal chest pain, coughing, and shortness of breath, potentially progressing to acute respiratory distress syndrome. In the central nervous system, symptoms might include visual disturbances, auditory changes, nausea, dizziness, and even seizures. Retinopathy of prematurity is a specific example of oxygen toxicity affecting the developing eyes of premature infants. Management involves carefully controlling oxygen concentrations and exposure times, especially in vulnerable populations.