Clinical Validation of Medasense Pain Response Index (PRI)

Medasense

Status: Completed

Conditions: Surgery; Pain

Treatments: Other: chronic beta-blocker treatment; Drug: Base level of remifentanil effect side concentration: 2ng/ml; Drug: Base level of remifentanil effect side concentration: 4ng/ml

Study type: Interventional

Funder types: Other

Identifiers

NCT01762332

0326-12-RMB (Other Identifier)

Medasense003

Details and patient eligibility

About

In our previous study, NCT01631695, we proposed and clinically evaluated the Medasense pain response index, PRI, in anesthetized patients undergoing surgery. Note: the name PRI has been changed to NoL (Nociception Level) Index.

The PRI is based on a non-linear combination of several pain-related physiological parameters into a one unique index (0-100).

In this study we aim to validate the performance of the PRI by:

1. investigating the patient's PRI response to surgical painful stimuli under different levels of analgesia:

   • Investigating patient's PRI response to surgical painful stimuli under two different levels of Remifentanil Target Control Infusion (TCI) rates.
   • Investigating patient's PRI response to standardized painful stimulus (Tetanic stimulus) with and without opioids.

2. investigating the effect of beta-blockers on PRI performance in patients taking chronic beta-blocker treatment.

The study is based on recording and analyzing the subject's physiological signals, while recording painful events, medication dosing and different clinical signs.

Full description

Pain is an unpleasant sensation, ranging from slight discomfort to intense suffering. Since pain is a subjective phenomenon, it has frequently defied objective, quantitative measurements. Today, in order to measure pain, subjective uni-dimensional scales are used to quantify pain. One of the most common scale used to rate a patient's pain intensity is the Numeric Pain Scale (NPS), usually scored from 0 to 100. Hitherto, those scales are based on the subjective evaluation of pain by the patient.

During anesthesia the patient cannot communicate and therefore the verbal or other report is impossible. As a consequence, due to misrepresentation of the existence or extent of pain, care providers may fail to estimate the correct measure of pain and give too much or too little medication, leading to possible complications and adverse reactions. A validated scoring system of subject's pain level, or as in the case of an anaesthetised patient, subject's nociception level, is therefore needed.

In this study the investigators intend to test and analyze the performances of Medasense pain response index, PRI, by comparing it with other standard pain related indicators (Heart Rate (HR), Heart Rate Variability (HRV), Skin Conductance, etc) before and after painful stimuli at different levels of analgesia. In addition, in order to reduce the variability between stimuli, a standardized stimulus (Tetanic ,30 sec, 100Hz, 60mA) will be given to all patients after sleep induction and before intubation, with and without administration of Fentanyl and the values of the PRI during these stimuli will be investigated.

Enrollment: 82 patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• ASA physical status 1-3
• Elective surgery

Exclusion criteria

• Pregnancy or lactation
• History of severe cardiac arrhythmias
• Abuse of alcohol or illicit drugs
• History of mental retardation, dementia, psychiatric disorders
• Allergy to any of the drugs to be used during anesthesia and recovery

Trial design

Primary purpose: Screening

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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82 participants in 3 patient groups

Low opioid level

Active Comparator group

Description:

Base level of remifentanil effect side concentration: 2ng/ml Stopped recruitment (May 2014)

Treatment:

Drug: Base level of remifentanil effect side concentration: 2ng/ml

High opioid level

Active Comparator group

Description:

Base level of remifentanil effect side concentration: 4ng/ml Stopped recruitment (May 2014)

Treatment:

Other: chronic beta-blocker treatment

Drug: Base level of remifentanil effect side concentration: 4ng/ml

chronic beta-blocker treatment

Other group

Description:

Patients with chronic beta-blocker treatment prior to surgery and study. Will all be allocated to the high opioid level arm without randomization. Continue recruitment.

Treatment:

Other: chronic beta-blocker treatment