1. Triple low, double low: it’s time to deal Achilles heel a single deadly blow 
M.D. Willingham, M.S. Avidan 
British Journal of Anaesthesia 
Volume 119, Issue 1, Pages 1-4 (July 2017)
DOI: /bja/aex132
Copyright © 2017 The Author(s) Terms and Conditions

2. Fig 1
Discordance between the frontal electroencephalogram (EEG) trace and bispectral index (BIS) values. (A and C) Frontal EEG traces at four sweep speeds (6.25, 12.5, 25, and 50 mm s−1). (B) Frontal EEG trace at two sweep speeds (6.25 and 50 mm s−1). (D) Frontal EEG trace at 25 mm s−1. The EEG shows features in keeping with sevoflurane general anaesthesia (delta waves at ∼1 Hz with phase-amplitude cross-frequency coupled alpha spindles at ∼10 Hz (A) and ∼12 Hz (B). The volatile anaesthetic concentrations are consistent with this interpretation. The BIS readings of 94 and 81 are misleading and might be attributable to a high-frequency electrical artefact that is visible in the EEG traces and might be influencing both the electromyography (in decibels) and BIS readings. The EEG in (C) is predominantly suppressed with occasional electrical bursts. These features are in keeping with deep general anaesthesia, hypothermia, or neuropathology. The BIS reading of 75 is misleading and is likely attributable to electrocardiogram (ECG) contamination of the EEG trace. This can be appreciated from the regular spikes in the EEG, which coincide with arterial pressure peaks. The EEG in (D) is persistently suppressed. This is in keeping with deep general anaesthesia, hypothermia, or neuropathology. The BIS reading of 40 is misleading and is likely attributable to ECG contamination of the EEG trace. The patient is hypothermic (33.9 °C) on cardiopulmonary bypass and the ECG shows ventricular fibrillation. The ECG fibrillation waves are contaminating the EEG trace and are likely influencing the BIS algorithm.
British Journal of Anaesthesia  , 1-4DOI: ( /bja/aex132)
Copyright © 2017 The Author(s) Terms and Conditions