The triple low state [low mean arterial pressure, low bispectral index (BIS) and a low minimum alveolar concentration (MAC)] fraction of anaesthetic during surgery) has been a controversial subject of interest in clinical practise. Previous retrospective studies have produced different conclusions on the association between a triple low state and postoperative 30-day mortality. This study was a systematic review of previous studies on the effects of the triple low state on postoperative 30-day mortality and a meta-analysis with a sample size larger than that of previous studies.