In univariate analysis, the risk factors associated with death were: cardiac arrhythmia (RR= 3.11; CI: 1.56 - 6.19), dyspnea (RR= 2.57; CI: 1.26 - 5.23), thorax retraction (RR= 3.44; CI: 1.25 - 9.5) and sclerema neonatorum (RR= 4.5; CI: 2.26 - 8.95).