BACKGROUND: Gasping is a natural reflex that enhances oxygenation and circulation during cardiopulmonary resuscitation (CPR). OBJECTIVES: This study sought to assess the relationship between gasping during out-of-hospital cardiac arrest and 1-year survival with favorable neurological outcomes. METHODS: The authors prospectively collected incidence of gasping on all evaluable subjects in a multicenter, randomized, controlled, National Institutes of Health-funded out-of-hospital cardiac arrest clinical trial from August 2007 to July 2009. The association between gasping and 1-year survival with favorable neurological function, defined as a Cerebral Performance Category (CPC) score