title: Initial evaluation of the Mobile Emergency Medical Services in the city of Porto Alegre, Brazil.
abstract: BACKGROUND
  Little is known about the immediate outcomes of the Mobile Emergency Medical Services (SAMU) in Brazil.
  
  
  OBJECTIVE
  To evaluate clinical predictors of survival of patients in cardiorespiratory arrest (CRA) in the nonhospital environment treated by the SAMU in the city of Porto Alegre.
  
  
  METHODS
  The present study has a prospective and observational design. The evaluated outcomes were 30-day survival and hospital discharge, in addition to the Cerebral Performance Category (CPC) score I-II.
  
  
  RESULTS
  From January to October 2008, a total of 593 patients in nontraumatic CRA were treated and 260 cardiopulmonary resuscitation (CPR) attempts were made. There was an initial successful outcome in 52 (20.0%) cases, with 16 patients (6.0%) alive on the 30th day and 10 being discharged from the hospital (3.9%), of which 6 (2.3%) presented CPC I-II score. The CPR at home was inversely associated with 30-day survival (p = 0.001) and hospital discharge survival (p = 0.02). An initial "shockable" rhythm (p = 0.008) was associated with 30-day survival. The response-time and collapse-time intervals until CPR start were significantly shorter in 30-day survivors. At multivariate analysis, independent 30-day mortality predictors were an initial shockable rhythm (odds ratio [OR] = 0.28 and 95% confidence interval [95%CI] = 0.10 - 0.81; p = 0.02) and CPR at home (OR = 3.0 and 95CI% = 1.04 - 8.7; p = 0.04).
  
  
  CONCLUSIONS
  The pre-hospital care of CRA in the city of Porto Alegre has limited results; however, they are comparable to the results from other international locations. It is necessary to reinforce each link of the survival chain to improve pre-hospital care, aiming at improving clinically relevant outcomes.
authors.affiliation: Serviço de Cardiologia, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2350, Porto Alegre, RS, Brazil.
authors.forename: Gladis
authors.initials: G
authors.lastname: Semensato
authors.forename: Leandro
authors.initials: L
authors.lastname: Zimerman
authors.forename: Luis Eduardo
authors.initials: LE
authors.lastname: Rohde
mesh_terms: D017677:Age Distribution; D000368:Aged; D000552:Ambulances / Q000706:statistics & numerical data*; D001938:Brazil; D016887:Cardiopulmonary Resuscitation / Q000706:statistics & numerical data; D004632:Emergency Medical Services / Q000706:statistics & numerical data; D005260:Female; D006323:Heart Arrest / Q000401:mortality / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D017678:Sex Distribution; D012737:Sex Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome