BACKGROUND: The incidence and risk factors of postoperative nausea and vomiting 
(PONV) and early PONV (ePONV) were evaluated in patients who underwent breast 
surgery with volatile anesthesia.
METHODS: In this retrospective study, multivariate logistic regression was used 
to determine incidence and identify risk factors for PONV.
RESULTS: Among 928 patients, 166 (18%) and 220 (24%) had ePONV and PONV, 
respectively. In multivariate analysis, anesthesia duration and use of 
desflurane were independent risk factors for ePONV. For PONV, anesthesia 
duration and Apfel score were independent risk factors.
CONCLUSIONS: Our results indicate that desflurane was the main cause of ePONV. 
However, during the delayed phase, a higher Apfel score was the strongest 
predictor. In the early and delayed phases, long anesthesia duration was 
associated with high risk of PONV. Thus, prolonged anesthesia and desflurane use 
should be avoided for patients at high risk of PONV, particularly those with 
high Apfel scores.