Cox regression analyses.

ASA = American Society of Anesthesiology classification of physical status; NS = non significant. Both Surgical delay, p = 0.08 and Time of Surgery, p = 0.20 were non significant in the univariate analysis. Other Non significant covariates in the univariate analyses were: Time of year, p = 0.67; Time of Admission, p = 0.25; Type of hospital, p = 0.19.