Problems in obtaining sufficient anaesthesia with propofol and remifentanil: three cases, a test infusion, and a review  S. Bache, L. Stendell, N.V. Olsen, K.S. Olsen  British Journal of Anaesthesia  Volume 110, Issue 5, Pages 741-746 (May 2013) DOI: 10.1093/bja/aes474 Copyright © 2013 The Author(s) Terms and Conditions

Fig 1 Data and observations from the remifentanil infusion test carried out on Subject A (left) and Subject B (right). (Top) An overview of the remifentanil infusion rates (Vinf), the calculated remifentanil plasma (Cp), and target (Ce) concentrations (calculated using Rugloop II, programmed with the pharmacokinetic parameters reported by Minto and colleagues12 and obtained from www.anesthesie.ugent.be/rugloop.htm) depicted over time (min). (Middle) Respiratory rate (bpm) and E′CO2 (kPa) depicted over time (min). (Bottom) Pupil diameter (mm) and algometry (kPa) depicted over time (min). *Unfortunately, the camera used to measure the pupil size in Subject B automatically turned off 13 min after the infusion was started. This was first discovered after 19 min. **The algometry values depicted as 1000 kPa should be interpreted as above 1000 kPa, as pressure applied above this level had the potential to damage the finger. British Journal of Anaesthesia 2013 110, 741-746DOI: (10.1093/bja/aes474) Copyright © 2013 The Author(s) Terms and Conditions