Background Respiratory failure is a known complication of cardiac operations and contributes to postoperative morbidity and death. This study assessed the relevance of risk factors in the development of respiratory failure, defined as postoperative ventilation exceeding 48 hours, and looked at the effect of respiratory failure on short-term and long-term mortality rates. Methods De-identified data for patients who underwent cardiac surgical procedures at The Prince Charles Hospital between January 2002 and December 2007 were collected prospectively and analyzed using logistic regression to identify significant risk factors associated with respiratory failure. Long-term mortality data were analyzed for patients who underwent operations between 1994 and 2005 using Kaplan-Meier survival curves. Results The risk factor analysis included 7,440 patients. Identified risk factors for respiratory failure included critical preoperative state, neurologic dysfunction, poor left ventricular function, active endocarditis, chronic obstructive pulmonary disease, elevated preoperative creatinine, previous cardiac operation, and age. Survival was assessed in 18,488 patients and demonstrated increased short-term and long-term mortality rates when respiratory failure developed and increased mortality rates with increasing duration of respiratory failure. Conclusions Respiratory failure is complication of cardiac operations associated with increased mortality and cost. Identification of patients at risk of respiratory failure may help select surgical candidates and aid resource planning and optimization.