Reductions in pressure and exposure will be made progressively, and medications such as bronchodilators and pulmonary surfactants may be used.Divers manage the risk of pulmonary damage by limiting exposure to levels shown to be generally acceptable by experimental evidence, using a system of accumulated oxygen toxicity units which are based on exposure time at specified partial pressures. In the event of emergency treatment for decompression illness, it may be necessary to exceed normal exposure limits to manage more critical symptoms.Retinopathy of prematurity may regress spontaneously, but should the disease progress beyond a threshold (defined as five contiguous or eight cumulative hours of stage 3 retinopathy of prematurity), both cryosurgery and laser surgery have been shown to reduce the risk of blindness as an outcome. Where the disease has progressed further, techniques such as scleral buckling and vitrectomy surgery may assist in re-attaching the retina. Repetitive exposure
Repeated exposure to potentially toxic oxygen concentrations in breathing gas is fairly common in hyperbaric activity, particularly in hyperbaric medicine, saturation diving, underwater habitats, and repetitive decompression diving. Research at the National Oceanic and Atmospheric Administration (NOAA) by R.W. Hamilton and others determined acceptable levels of exposure for single and repeated exposures. A distinction is made between acceptable exposure for acute and chronic toxicity, but these are really the extremes of a possible continuous range of exposures.
A study by Welslau in 1996 reported 16 incidents out of a population of 107,264 patients (0.015%), while Hampson and Atik in 2003 found a rate of 0.03%. Yildiz, Ay and Qyrdedi, in a summary of 36,500 patient treatments between 1996 and 2003, reported only 3 oxygen toxicity incidents, giving a rate of 0.008%. A later review of over 80,000 patient treatments revealed an even lower rate: 0.0024%. The reduction in incidence may be partly due to use of a mask (rather than a hood) to deliver oxygen.Bronchopulmonary dysplasia is among the most common complications of prematurely born infants and its incidence has grown as the survival of extremely premature infants has increased. Nevertheless, the severity has decreased as better management of supplemental oxygen has resulted in the disease now being related mainly to factors other than hyperoxia.In 1997 a summary of studies of neonatal intensive care units in industrialised countries showed that up to 60% of low birth weight babies developed retinopathy of prematurity, which rose to 72% in extremely low birth weight babies, defined as less than 1 kg (2.2 lb) at birth. However, severe outcomes are much less frequent: for very low birth weight babies—those less than 1.5 kg (3.3 lb) at birth—the incidence of blindness was found to be no more than 8%. History
Central nervous system toxicity was first described by Paul Bert in 1878. He showed that oxygen was toxic to insects, arachnids, myriapods, molluscs, earthworms, fungi, germinating seeds, birds, and other animals.