Surgical pleth index: prospective validation of the score to predict moderate-to-severe postoperative pain

Abstract

Background: Reported outcome benefits after surgical pleth index (SPI, GE Healthcare, Helsinki, Finland) guided anaesthesia are conflicting. One potential explanation may be the lack of evidence for the selection of meaningful SPI target values. A recently published trial found an SPI cut-off of 30 as a 'best-fit' to predict moderate-to-severe acute postoperative pain. This prospective trial was designed to validate this target and to investigate the influence of patient age on SPI in this context. Methods: After ethics approval, 200 patients undergoing non-emergency surgery were enrolled. Data related to SPI, heart rate (HR), and mean arterial pressure (MAP) were recorded for the last 5 min of surgery, just before arousal. After admission to recovery, pain scores (numeric rating scale [NRS], 0e10) were obtained every 5 min for 15 min. Results: The data of 196 patients were analysed. Receiver-operating curve analysis showed a cut-off SPI value of 29 to be the optimum intraoperative target to discriminate between NRS 0e3 and 4e10. This confirms the 'best fit' cut-off for SPI published previously. Though still superior to HR and MAP, the sensitivity and specificity of the SPI were only poor. Age had no influence on the predictive accuracy of SPI. Conclusions: An SPI of approximately 30 was confirmed as having the best sensitivity/specificity to predict moderate-tosevere pain in the postanaesthesia care unit. However, the predictive accuracy was overall poor and not influenced by patient age. Clinical trial registration: ACTRN12617001475336.

Objective monitoring of nociception: a review of current commercial solutions

“…Although SPI has been suggested to have some value for the prediction of acute postoperative pain (positive predictive value [PPV] 89.7 for SPI >30 indicating pain >3/10), 57 a more recent study testing the SPI cut-off value of 30 for the prediction of moderate-to-severe pain prospectively in 200 patients has essentially refuted this (PPV for SPI >30 to predict pain >3/ 10 only 60%). 63…”

Predicting acute postoperative pain by the Qnox score at the end of surgery: a prospective observational study

“…In order to detect such difference from a ROC AUC of 0.5 (¼tossing a coin), 50 patients in each group noemild (NRS 0e3) and moderateesevere (NRS 4e10) were deemed necessary. As the event rate between the two groups was unlikely to be 1:1, but more likely 2:1 (experience from previous own research 7 ), 150 patients were included in the study.…”

Pain and Stress Detection Using Wearable Sensors and Devices—A Review

“…The SPI has been proved to correlate with self-reporting systems [ 77 ]; however, the appropriate selection of SPI target values has not been established yet. The representation of different score ranges of SPI (e.g., prediction of moderate-to-severe postoperative pain [ 78 ]) is still a major topic in the research field.…”