Spectral Entropy and bispectral index as guidance for propofol-remifentanil anaesthesia in combination with regional anaesthesia compared with a standard clinical practice group

Clinical effectiveness and cost-effectiveness of depth of anaesthesia monitoring (E-Entropy, Bispectral Index and Narcotrend): a systematic review and economic evaluation

“…In the remainder it was unclear, and in one trial it was judged to be high because of an imbalance in the percentage of patients excluded from the analysis between trial arms. 62 In general, it was not considered that risk of other forms of bias were present. However, in one trial the risk was considered high because of the study being funded in part by the BIS module manufacturer.…”

“…62 Risk of bias because of random sequence generation was deemed unclear in the remaining three trials, which provided no information on the method of sequence generation.…”

“…There were seven (46%) 45,46,48,52,53,59,62 that included fewer than 100 patients and five (33%) 48,51,61,63,64 that had between 101 and 200 patients. One trial included 921 patients, 47 another included 5309 40 and another, the largest, included 6041 patients.…”

“…One publication reports the main trial results, 79 and a second publication focuses on recovery outcomes from the trial. 74 ) Six (55%) 40,44,46,49,51,62 of the 11 BIS trials reported a statistical sample size calculation based on a nominated primary outcome, although one of these trials reported that the number of patients chosen was arbitrary rather than being based on a statistical calculation. 49 The Cochrane BIS review 34 did not comment on sample size power calculations in the studies included.…”

“…Six (55%) 40,44,46,48,49,62 of the 11 BIS trials reported patient attrition. The attrition rate varied from 1.5% 40 to 15% 49 of the total number of patients enrolled.…”