OBJECTIVES: Risk factors of reintubation were studied after planned extubation in a surgical ICU. METHODS: A retrospective case-control study was performed in patients ventilated more than 48 h. Case patients (CP; n=20) were those requiring reintubation within 72 h after planned extubation, and control patients ( n=20) were those successfully extubated. Controls were matched with CP for age, admission SAPS II, and duration of mechanical ventilation before extubation. RESULTS: CP had a significantly higher maximal respiratory rate during T tube trial and lower minimal SaO(2). More CP were treated with volume assist controlled (VAC) mode on the morning of extubation (60% vs. 25%). Multivariate analysis identified only VAC mode as an independent factor associated with reintubation. CP had longer ICU stay and a higher incidence of nosocomial pneumonia and tracheostomy. There was no difference in ICU mortality between CP and CTLP. CONCLUSIONS: The VAC mode of weaning of surgical ICU patients is associated with an increased incidence of reintubation and morbidity after planned extubation. This probably reflects the clinical condition of patients unable to tolerate pressure support.