Are electrocardiogram electrodes acceptable for electroencephalogram bispectral index monitoring?

Background: The monitoring of electroencephalogram bispectral index (EEG-BI S) during anaesthesia reduces anaesthetic use and improves recovery. Howeve r, it also increases the direct costs of anaesthesia due to the need for sp ecial EEC electrodes. In the present study we tested the feasibility of les s expensive electrocardiogram (ECG) electrodes for EEG-BIS monitoring. Methods: In the first part of the study we compared skin-electrode impedanc es when EEG electrodes were used after alcohol swab pretreatment of skin to impedances when ECG electrodes were used after alcohol swab pretreatment w ith or without skin abrasion paste. In the second part of the study we eval uated the difference in parallel BIS values collected with two BIS monitors , using either ECC electrodes or EEG electrodes. In the third part of the s tudy we compared parallel BIS values collected with two sets of EEG electro des. Results: Skin pretreatment with abrasion paste led to lower impedances with ECG electrodes than did alcohol swab pretreatment of skin with EEC electro des. When the skin was pretreated with alcohol swab, higher impedances were measured with ECG electrodes than with EEG electrodes. In most patients, B IS values collected with ECG electrodes were also higher than those collect ed with adhesive EEG electrodes. The difference between parallel BIS values collected with two sets of adhesive EEC electrodes was smaller than the di fference between BIS values collected with ECC and EEG electrode sets. Conclusion: Low skin-electrode impedances indicating reliable skin-electrod e contact can be ensured with inexpensive pregelled ECC electrodes only if the skin is carefully prepared with both abrasion paste and alcohol. When o nly alcohol Pretreatment of skin is used, the BIS values collected with EEG electrodes and ECG electrodes are not equal. EEG-BIS monitoring with prege lled ECG electrodes is recommended only if skin is prepared with abrasion p aste before attaching the electrodes.