Table 2.
Properties of the included studies in this review
| First author | Year | Nociception monitor (target for intervention groupa) | Number of patients (intervention/control) | Surgery | Anesthesia technique | Hypnosis monitor (target for all patients) | Patients (ASA, age) | Primary outcome | Comments |
|---|---|---|---|---|---|---|---|---|---|
| Won [21] | 2016 | SPI (20–50) | 23/22 | Thyroid resection |
– Sevoflurane – Oxycodone – Rocuronium |
BIS (40–60) | ASA 1–2, 20–65 years. | Intraoperative oxycodone consumption | Single center study. Rescue medication (thiopental) in case of somatic movement despite SPI and BIS values within target boundaries |
| Bergmann [17] | 2013 | SPI (20–50 and Δ < 10) | 76/75 | Orthopedic surgery in a supine or beach-chair position |
– Propofol – Remifentanil – Mivacurium |
SE (40–60) | ASA 1–3, 18–75 years | Propofol (1) and remifentanil (2) consumption. Recovery time (3) | Single center study. There was maximum remifentanil infusion rate. No difference in postoperative pain |
| Chen [18] | 2010 | SPIb (20–50) | 40/40 | ENT surgery |
– Propofol TCI – Remifentanil TCI – Rocuronium |
BIS (40–60) | ASA 1–2, 18–70 years | Number of episodes with inadequate anesthesiad | Single center study. No difference in postoperative pain |
| Colombo [19] | 2015 | SPI (< 50) | 30/30 | Laparoscopic chole-cystectomy |
– Propofol TCI – Remifentanil TCI – Cis-atracurium |
SE (40–60) | ASA 1–2, 18–50 years | Sympathetic modulation | Single center study |
| Gruenewald [20] | 2014 | SPI (< 50) | 42/40 | Gynecological or orthopedic surgery |
– Sevoflurane – Sufentanil – Rocuronium |
BIS (40–60) | ASA 1–2, 18–65 years | Incidence of unwanted somatic events | Single center study |
| Jain [16] | 2019 | SPI (20–50) | 70/70 | Laparoscopic cholecystectomy |
– Sevoflurane – Fentanyl |
BIS (40–60) | ASA 1–2, 18–65 years | Intraoperative fentanyl consumption | Single center study |
| Dundar [22] | 2018 | ANI (50–70) | 22/22 | Breast surgery |
– Sevoflurane – Remifentanil – Thoracic para-vertebral block |
BIS (40–60) | ASA 1–2, females, 18–65 years | Total remifentanil consumption (mentioned in “Discussion”) | Study sites not specified. All patients received a thoracic paravertebral block |
| Upton [24] | 2017 | ANI (≥ 50) | 24/26 | Lumbar discectomy or laminectomy |
– Sevoflurane – Fentanyl and non-opioid analgesia – Rocuronium |
BIS (40–60) | ASA 1–2, 18–75 years | Postoperative NRS | Single center study |
| Szental [23] | 2015 | ANI (> 50) | 59/60 | Laparoscopic cholecystectomy |
– Sevoflurane or desflurane –Fentanyl, morphine and non-opioid analgesia –Neuromuscular blocker |
BIS depth not specified | ASA –, 18–75 years | VAS > 50 mm in first postoperative hour | Study performed in two centers |
| Meijer [15] | 2018 | Nociception level (10–25) | 40/40 | Major abdominal surgery: urology (48%), abdominal surgery (39%), gynecology (14%) |
– Propofol TCI – Remifentanil TCI – Rocuronium |
BIS (45–55) | ASA 1–3, 18–80 years | Propofol (1) and remifentanil (2) consumption. Incidence of inadequate anesthesia events (3) | Single center study |
| Martinez [25] | 2010 | Beat-to-beat cardiovascular indexc (< 60 and absence of conventional signs of nociception) | 71/75 | Gastroscopy and/or colonoscopy |
– Propofol TCI – Alfentanil |
BIS (40–60) | ASA 1–2, 20–75 years | Reduction in unwanted movements | Single center study. Beat-to-beat blood pressure was measured using the Finapress™ device using a finger cuff. |
| Sabourdin [26] | 2017 | Pupillometry (pupil diameter 5–30% of baseline) | 25/30 | Gynecological surgery |
– Propofol TCI – Remifentanil TCI – Atracurium |
BIS (40–60) | ASA 1–2, females, 18–60 years | Remifentanil consumption | Single center study. In case of large hemodynamic changes remifentanil TCI could be changed and/or vasoactive medication or fluids could be given |
ANI analgesia nociception index, BIS bispectral index, ENT ear-nose-and-throat, SE state entropy, SPI surgical plethysmographic index
aThe target indicates adequate analgesia. A monitor value outside the target range leads to additional opioid administration according to the protocol of the individual studies
bThe authors named their monitoring index the surgical stress index which is equivalent to the SPI
cThe beat-to-beat cardiovascular depth of anesthesia index (CARDEAN 2.0) is a nociceptive algorithm based on changes in blood pressure and tachycardia
dInadequate anesthesia: mean blood pressure > 120% of baseline or > 100 mmHg or mean blood pressure < 80% of baseline or < 60 mmHg; heart rate > 90 beats min−1or < 80% of baseline or < 45 beats min−1; somatic arousal; somatic response