1. Bispectral index is related to the spread of spinal sensory block in patients with combined spinal and general anaesthesia 
R Iida, K Iwasaki, J Kato, S Ogawa 
British Journal of Anaesthesia 
Volume 106, Issue 2, Pages (February 2011)
DOI: /bja/aeq359
Copyright © 2011 The Author(s) Terms and Conditions

2. Fig 1
BIS values of one representative patient during 1–20 min after the effect-site concentration of propofol reached and remained 3.0 μg ml−1.
British Journal of Anaesthesia  , DOI: ( /bja/aeq359)
Copyright © 2011 The Author(s) Terms and Conditions

3. Fig 2
Scattergram showing the relationship between the spinal thoracic level of spinal sensory blockade and BIS values at 15 min after the spinal administration of bupivacaine. The correlation coefficient for this time was (P=0.195). Spinal anaesthesia itself did not cause any significant decreases in BIS values at 15 min after spinal anaesthesia.
British Journal of Anaesthesia  , DOI: ( /bja/aeq359)
Copyright © 2011 The Author(s) Terms and Conditions

4. Fig 3
Scattergram showing the relationship between spinal thoracic level of spinal sensory blockade at 15 min after spinal anaesthesia and BIS values during the periods between 1 and 5 min (a), 6 and 10 min (b), 11 and 15 min (c), and 16 and 20 min (d) after the effect-site concentration attained a constant level of 3.0 µg ml−1. The points represent the mean values calculated from data for the 5 min interval for individual patients. The vertical axis represents BIS values. The horizontal axis represents the spinal thoracic level in which 0.0, 1.0, and 2.0 correspond to C8, Th1, and Th2, respectively. The spinal levels are the mean values of the right and left spinal thoracic levels; therefore, the spinal levels are represented as 0.0, 0.5, 1.0, 1.5, 2.0, and so on. The correlation coefficients between spinal levels and BIS values were 0.800, 0.848, 0.804, and 0.801, respectively, at 1–5, 6–10, 11–15, and 16–20 min after the effect-site concentration of propofol reached and remained at 3.0 µg ml−1. The regression coefficients on each linear regression line were , , , and , respectively, at 1–5, 6–10, 11–15, and 16–20 min.
British Journal of Anaesthesia  , DOI: ( /bja/aeq359)
Copyright © 2011 The Author(s) Terms and Conditions