Introduction: Asthma, classically, is defined as a chronic inflammatory disease of the airways; characterized by a history of respiratory symptoms, such as wheezing, shortness of breath, chest tightness, and cough, that vary over time and in intensity. Near-fatal asthma are situations in which asthma exacerbations can lead to cardiorespiratory arrest, orotracheal intubation and mechanical ventilation, admission to an intensive care unit (ICU); Knowing the characteristics and risk factors that predict this situation in a patient who arrives at the emergency room is very important for early action. Clinical case: We present a 23-year-old patient with a history of asthma since he was 5 years old and irregular treatment; with a stay in the ICU and on mechanical ventilation for almost fatal asthma 8 months before; the clinical signs and the arterial blood gas analysis predicted an almost fata...