Pupillometry - Future of Objective Pain Reaction Measurement While Unconscious
Condition: Pain
MeSH terms: Unconsciousness
Study type: Interventional

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.
    

Intervention name(s): Pupil reflex dilation measurement (PRD); PPI (Pupillary Pain Index); lidocaine; Placebo; Bispectral Index (BIS); HR; BP
Intervention type(s): Device; Device; Drug; Drug; Device; Device; Device
Intervention description(s): Pupillary Reflex Dilation (PRD) measured for 60 s during orotracheal intubation using a video pupillometer; Pupillary Reflex Dilation (PRD) measured using a video pupillometer 5 min after orotracheal intubation; 1.5 mg/kg lidocaine/ 100ml 0,9% NaCl iv 10min before intubation; 100ml 0,9% NaCl iv 10min before intubation; Bispectral Index will be monitored to assess the depth of anaesthesia; HR in beats/min will be measured by the electrocardiogram monitor; BP will be measured automatically by an occluding upper arm cuff
Other intervention name(s): lidocaine, Xylocaine; 0,9% natrium chloratum, sodium chloride
Intervention MeSH terms: Lidocaine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Diagnostic
Keywords: lidocaine; intubation; pupillometry; hemodynamic response; pain; reflex; pupillary monitoring; intraoperative; analgesia; general anesthesia