Immediate complications are secondary to hypoxia and acidosis. The immediate threat is the effect on the cardiovascular system. Hypoxia and acidosis may lead to cardiac dysrhythmias, including ventricular fibrillation and asystole. Myocardial damage may lead to cardiogenic shock. Monitor and maintain intravascular volume and blood pressure. Central venous pressure (CVP) monitoring is useful in those patients requiring intensive care.Aspiration of fresh or salt water alters the function of surfactant, causing injury to the alveoli and pulmonary capillaries. Increased capillary permeability can worsen the hypoxia. Continuous pulse oximetry is useful. The early use of supplemental oxygen with high levels of positive end-expiratory pressure is helpful in reversing hypoxemia.Central nervous system effects depend on the severity and duration of hypoxia. Post hypoxic cerebral hypo perfusion may occur. Cerebral edema and intracranial hypertension secondary to hypoxic neuronal injury is frequently observed, but studies have shown that invasive monitoring of intracranial pressure is neither useful nor necessary in near-drowning incidents.Near-drowning patients frequently develop pneumonia, often due to secondary bacterial infections. Whether prophylactic antibiotics are beneficial is still controversial. Chemical pneumonitis also is not infrequent, especially if the submersion occurs in chlorinated or severely contaminated pools.