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Pupillometry - Future of Objective Pain Reaction Measurement While Unconscious

Not Applicable
Completed
Conditions
Pain
Interventions
Device: Pupil reflex dilation measurement (PRD)
Device: PPI (Pupillary Pain Index)
Drug: Placebo
Device: Bispectral Index (BIS)
Device: HR
Device: BP
Registration Number
NCT04000126
Lead Sponsor
University of Warmia and Mazury
Brief Summary

This study aims to assess the usefulness of pupillometry as a nociceptive indicator during elective orotracheal intubation in patients given intravenous lignocaine pre-intubation as compared to a placebo pre-intubation.

Detailed Description

Laryngoscopy and tracheal intubation are associated with a sympathetic discharge caused by stimulation of the upper respiratory tract. Venous lidocaine is the agent most used to attenuate the hemodynamic response to laryngoscopy and intubation. Hemodynamic response might be masked by the drugs the patient is taking and its status (ex. sepsis). There's a need for an objective pain assessment method while the patient is unconscious, to maintain a proper level of analgesia and to control the hemodynamic response in order to decrease systemic repercussions.

This single-blind, randomized, single center, prospective study was approved by the Bioethics Committee of the University of Warmia and Mazury under the report number 11/2019 21st of February 2019.

Patients scheduled for elective surgery under general anesthesia with tracheal intubation were divided into three groups:

Group 1: anaesthetic induction with standard doses iv was performed (fentanyl 3mcg/kg, propofol 2mg/kg, rocuronium 0,6mg/kg).

Group 2: same as in group 1 + lidocaine 1,5mg/kg w 100ml 0,9% NaCl 10 min before intubation.

Group 3 (placebo group): same as group 1 + 100ml 0,9% NaCl 10 min before intubation

The values for blood pressure (NIBP), heart rate (HR), Train of four (TOF) and bispectral index (BIS) were measured in all groups during the whole time of the protocol. PRD (Pupillary Reflex Dilation) was measured in the exact time of intubation. Additionally, after intubation PPI (Pupillary Pain Index) was checked.

During the whole protocol BIS value was maintained to be equal to or less than 50, if this value was not reached, a venous increment of 1mg/kg of propofol was administered.

Hypertension was considered when the BP values were 20% above baseline values or if Systolic Blood Pressure (SBP) \> 140 mmHg. Hypotension was considered when the Blood Pressure (BP) values were 20% below baseline values or if SBP \> 90 mmHg. Tachycardia was considered when the Heart Rate (HR) values were 20% above baseline values or if HR \> 100 mmHg. Bradycardia was considered for HR values under 50 bpm.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
90
Inclusion Criteria
  • Physical State 1 or 2 of the American Society of Anesthesiology (ASA)
  • Electively scheduled for surgery requiring general anesthesia
  • Age >18 years
Exclusion Criteria
  • Difficult airway
  • Unanticipated difficult airway based on the previous history of difficult intubation
  • Urgently scheduled for surgery requiring general anesthesia
  • Ophthalmologic pathology precluding pupillometry, ex. Horner's syndrome, Sjogrens syndrome
  • Anisocoria
  • History of opioid abuse
  • Subjects who are or may be pregnant
  • Unable to converse in Polish
  • History of psychiatric/cognitive disease
  • Patients who do not give informed consent
  • Patients with contraindications or history of hypersensitivity to lidocaine
  • Patients with coronary ischemic disease
  • Patients with atrioventricular block at any grade
  • Patients with diagnosed cardiac arrhythmias
  • Patients with heart failure
  • Patients who are taking drugs influencing the pupil size
  • Patients with pacemaker
  • Patients younger than 18 years of age
  • History of chronic pain, chronic opioid use (> 3 months)

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Control CPPI (Pupillary Pain Index)This group will be given induction anesthesia agents in standard doses (fentanyl 3mcg/kg, propofol 2mg/ kg, rocuronium 0,6mg/kg)
Lignocaine group LHRThis group will be given additionally 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation
Control CPupil reflex dilation measurement (PRD)This group will be given induction anesthesia agents in standard doses (fentanyl 3mcg/kg, propofol 2mg/ kg, rocuronium 0,6mg/kg)
Lignocaine group LPupil reflex dilation measurement (PRD)This group will be given additionally 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation
Lignocaine group LBPThis group will be given additionally 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation
Placebo PPlaceboThis group will be given additionally 100 ml 0,9% NaCl iv 10 min before intubation
Control CBispectral Index (BIS)This group will be given induction anesthesia agents in standard doses (fentanyl 3mcg/kg, propofol 2mg/ kg, rocuronium 0,6mg/kg)
Control CHRThis group will be given induction anesthesia agents in standard doses (fentanyl 3mcg/kg, propofol 2mg/ kg, rocuronium 0,6mg/kg)
Placebo PPupil reflex dilation measurement (PRD)This group will be given additionally 100 ml 0,9% NaCl iv 10 min before intubation
Placebo PPPI (Pupillary Pain Index)This group will be given additionally 100 ml 0,9% NaCl iv 10 min before intubation
Placebo PHRThis group will be given additionally 100 ml 0,9% NaCl iv 10 min before intubation
Placebo PBPThis group will be given additionally 100 ml 0,9% NaCl iv 10 min before intubation
Lignocaine group LPPI (Pupillary Pain Index)This group will be given additionally 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation
Lignocaine group LBispectral Index (BIS)This group will be given additionally 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation
Placebo PBispectral Index (BIS)This group will be given additionally 100 ml 0,9% NaCl iv 10 min before intubation
Control CBPThis group will be given induction anesthesia agents in standard doses (fentanyl 3mcg/kg, propofol 2mg/ kg, rocuronium 0,6mg/kg)
Lignocaine group LlidocaineThis group will be given additionally 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation
Primary Outcome Measures
NameTimeMethod
Usefulness of Pupillary Reflex Dilation (PRD) measured using a video pupillometer in determining the role of lidocaine iv before intubation.PRD: during the exact time of intubation (continuous measurement for 60 seconds)

Level of analgesia will be investigated in all groups (placebo, lidocaine, control) basing on the autonomous system activation during intubation by measuring variation of pupil diameter (% and mm).

Secondary Outcome Measures
NameTimeMethod
The influence of intravenous lidocaine on level of analgesia during orotracheal intubationPRD: during the exact time of intubation (continuous measurement for 60 seconds)

Changes that occur in PRD measured using video pupillometer as a response to an analgesic intervention will be investigated in all groups (placebo, lidocaine, control).

The influence of intravenous lidocaine on level of analgesia during orotracheal intubation.BP - baseline and 0,1,2,3,4 minutes post-intubation

Level of analgesia will be investigated in all groups (placebo, lidocaine, control) basing on the autonomous system activation during intubation by measuring changes in BP (mmHg)

The influence of intravenous lidocaine on PPI5 minutes post-intubation

Changes that occur in PPI measure using video pupillometer as a response to an analgesic intervention will be investigated in all groups (placebo, lidocaine, control).

Correlation between PRD and PPI (Pupillary Pain Index) measured using video pupillometer and BIS (Bispectral Index)BIS - baseline, during intubation, 0,1,2,3,4,5 minutes post-intubation, PRD: during the exact time of intubation (continuous measurement for 60 seconds), PPI - 5 minutes post-intubation

Changes that occur in PRD and PPI as a response to an analgesic intervention will be investigated in all groups (placebo, lidocaine, control) and correlated to BIS in all groups.

Trial Locations

Locations (1)

Anesthesiology and Intensive Care Clinical Ward, Clinical University Hospital

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Olsztyn, Warmian-masurian, Poland

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