Reliability of body‐weight scalars on the assessment of propofol induction dose in obese patients

Background Obese patients require specific perioperative care when compared with non‐obese patients. The present study aimed to analyse the ability of size descriptors to estimate propofol induction dose in class II and III obese patients. Methods A cross‐sectional study on adult patients with body mass index (BMI) equal to or greater than 35 kg/m2 and on adult patients with BMI lower than 35 kg/m2 was carried out. General anaesthesia was induced with remifentanil, propofol and rocuronium. Propofol infusion was started at 2000 mg/h until loss of consciousness. Bioelectrical impedance analysis and Brice modified interview was completed during pre‐ and post‐operative evaluation, respectively. Measurements of propofol plasma concentration were performed using gas chromatography/ion trap‐mass spectrometry. Results Forty patients were enrolled in the study. The median values of fat free mass (FFM) in BMI