Correlation between incremental remifentanil doses and the Nociception Level (NOL) index response after intraoperative noxious stimuli

Abstract

Background The Pain Monitoring Device (PMD) monitor (Medasense Biometrics Ltd., Ramat Gan, Israel) uses the Nociception Level (NOL) index, a multiple parameterderived index that has recently shown a good sensitivity and specificity to detect noxious stimuli. The aim of this study was to assess the latest version of the device (PMD200 TM) on variations of the NOL response after standardized tetanic stimuli to study the correlation between remifentanil doses and NOL. Methods Data from 26 patients undergoing midline laparotomy and receiving a desflurane-remifentanil-based anesthetic coupled with low thoracic epidural analgesia were analyzed. A standardized tetanic stimulus was applied to the forearm of the patients at different remifentanil infusion rates. The primary aim was to evaluate the correlation between post-tetanic stimulation NOL values from the PMD200 and remifentanil doses. The NOL index variations after experimental and clinical stimuli were also compared with heart rate (HR), mean arterial pressure (MAP), and Bispectral Index TM (BIS). Results A correlation between post-tetanic stimulation NOL values and remifentanil doses was found (r =-0.56; 95% confidence interval [CI],-0.70 to-0.44; P\0.001). The NOL discriminated noxious from non-noxious states with the maximal Youden's index value of the NOL receiver operating characteristic (ROC) curve showing a specificity of 88% (95% CI, 69.0 to 100) and sensitivity of 79.1% (95% CI, 56.2 to 95.5). The area under the NOL ROC curve (AUC, 0.9; 95% CI, 0.84 to 0.95) was significantly different from the other variables (P \ 0.001 vs HR; P \ 0.001 vs MAP; P \ 0.001 vs BIS). Conclusions The NOL value after noxious stimulus decreased with incremental remifentanil doses, showing a significant inverse correlation between the NOL index and opioid doses. The sensitivity and specificity of NOL to discriminate between noxious and non-noxious stimuli suggests its interesting potential as a monitor of nociception intensity during anesthesia.

Transplantation faciale : anesthésie et autres considérations organisationnelles

“…The NOL monitoring allowed us to titrate the amount of opioid that we used during the non-stimulating phases of the surgery. 19 Finally, the synchronization of the two different surgeries was very important to reduce the ischemic time of the graft to a minimum and to allow the other organs of the donor to be procured in an optimal time. 20…”

“…The NOL monitoring allowed us to titrate the amount of opioid that we used during the non-stimulating phases of the surgery. 19 …”

Effect of electroencephalography-guided anesthesia on neurocognitive disorders in elderly patients undergoing major non-cardiac surgery: A trial protocol The POEGEA trial (POncd Elderly GEneral Anesthesia)

“…In our proposed study, remifentanil infusion will be guided in both groups on a nociception index, the NOL index. The NOL index is a tested and validated measure that shows a high correlation between pain measurements and doses of intraoperative opioids and is commonly used in our center at Maisonneuve-Rosemont Hospital / CEMTL [ 38 , 39 ]. Moreover, mean blood pressure targets will be personalized, and cerebral oximetry monitoring used to ensure comparability of the two groups regarding intraoperative hemodynamic management.…”

Effect of Laryngeal Mask Airway Insertion on Parameters Derived From Catacrotic Phase of Photoplethysmography Under Different Concentrations of Remifentanil

“…Although different study protocols have been proposed to examine the correlation between measures and balance of NAN, for example, some researchers [25] – [27] applied tetanic stimulus at varying concentrations of remifentanil in one person whereas Bonhomme et al [28] , Rantanen et al [29] , and our study assigned patients to several groups and observed the response of each patient to intraoperative stimulation at only one target concentration of analgesics, the essence of study design is identical, that is, keeping hypnotic level and nociception level constant when altering the level of analgesia. It is well known that general anesthesia is mainly consisted of hypnosis and analgesia; therefore, the prerequisite for analyzing analgesia during general anesthesia is to adjust the level of hypnosis to an adequate and appropriate state.…”

“…Moreover, the discarded data (−10 to +10 s) could separate the data before and after the event clearly without losing the crucial information generated by stimulus. Both maximum and average value have been used to describe the reactions to stimulus [25] – [28] . Maximum could preferably characterize some salient features which increase with the existence of noxious event, but it is vulnerable to outliers and could not explain the decreased features felicitously.…”