[A riverine emergency health service: characteristics and factors related to patients' clinical evolution].

The study aimed to describe the profile of patients and the care provided by the Mobile Riverine Emergency Medical Service (SAMU) in river-dwelling communities of the Amazon and to identify factors related to patients' evolution during care by this service. This descriptive study was conducted in two stages: in the first, the data were obtained on care for individuals in the service from 2009 to 2015; in the second, the data collection was prospective during the first semester of 2016, and patients' evolution was assessed with the Rapid Emergency Medicine Score. In all the periods analyzed, some 90% of the care included medical evacuation, varying over the years as to the type of boat used most frequently in transporting the patients. The most frequent reasons for care were signs and symptoms of unknown etiology and external causes. Of the patients transported by the service in the first semester of 2016, 68.5% maintained their clinical status, 18% worsened, and 13.5% improved during care. For patients seen during this period, the mean response and total riverine care times were 84 and 172 minutes, respectively. There was an association between evolution and incidents involving venomous snakes, acute pain, age, initial severity, and destination of the patient. Causes of care were related to worsening clinical status during care, and patients who worsened were younger and in less serious condition and were more frequently evacuated to hospitals. The profile of patients and care in the riverine SAMU pointed to the need for a revision of this service's objectives and structuring.