Epidemiology, pathophysiology, clinical evaluation, and treatment of carbon monoxide poisoning in child, infant, and fetus

Carbon monoxide (CO) poisoning is one of the most common types of poisoning causing death worldwide. In our country, it occurs particularly during winter as a result of leak from stove or water heater, or as result of inhalation during a fire. Although most poisonings occur accidentally, some cases are suicide attempt. As CO is a substance that is not visible and has no taste or smell and is therefore difficult to detect, the gas can be a "silent killer" that is not noticed until effects develop. CO reacts with oxygen, creating carboxy hemoglobin (COHb), which leads to tissue hypoxia. In addition, it has direct effect of causing cellular damage. Although symptoms of acute poisoning are most commonly observed in patients admitted to emergency rooms, effects of chronic exposure to CO can also seen. Clinically, although it affects all organ systems, involvement of central nervous system (CNS) and cardiovascular system is predominant. Most common poisoning symptoms are weakness, dizziness, headache, nausea, and nonspecific flu-like symptoms, like vomiting. Depending on severity of exposure, seizures, syncope, and arrhythmia may also be observed. In pregnant women, fetus can be harmed with relatively low level of COHb. Poisoning in infants has a more severe course than seen in other age groups. Symptoms must be associated with cause of poisoning, and careful anamnesis and treatment must be conducted quickly. Oxygen is the antidote for CO. It is administered through a mask in the form of normobaric oxygen therapy or through specific devices in the form of hyperbaric oxygen therapy. In this review, clinical data and current diagnostic and therapeutic approaches concerning CO poisoning are discussed.