Skin Conductance Fluctuations Per Sec and NRS to Monitor Pain
Condition: Pain
Study type: Observational

Summary: 
      To provide a preliminary evaluation of the correlation between Numeric rating Score (NRS) and
      skin conductance responses per second at rest and in response to a painful stimulus.
      Sensitivity and specificity will be calculated for NRS and skin conductance responses per sec
      to a standardized painful stimulus. Furthermore, predictors of pain will be examined.
    

Detailed description: 
      Cardiac surgery patients will be consented for participation in this trial. They will be
      asked about their pre-existing pain, anxiety about the needle-insertion and anxiety about the
      outcome of the operation, and employment status. This information will be obtained from
      self-reported schemas from the patients about presence/absence of pain and anxiety (the
      response options: yes/no) (1). The intensities of pain and anxiety will measured with NRS
      also ranging from 0 to 10 with one statement in each range: 0 no pain and 10 worst possible
      pain, and 0 no anxiety and 10 worst possible anxiety. The participants were requested to mark
      the point at the line that best agreed with how the pain and anxiety were experienced. The
      intensity of pain scored more than 3 on NRS was considered to be equal to moderate pain or
      more (1). Furthermore, patients in the Cardiac Surgery unit will be observed when undergoing
      pre-defined standardized painful stimuli as part of the standard of care treatment prior to
      and during surgery. The proposed study is structured using three events.

        -  Event 1: no stimuli, the period before placement of an arterial catheter when the
           patient has been administered diazepam, but is awake and calm. The registration will be
           for 1 min, 1 min before anticipated arterial line placement.

        -  Event 2: standardized painful stimulus, arterial catheter placement, with diazepam as
           premedication. The registration will be during arterial catheter placement.

        -  Event 3: no stimuli; patient is anesthetized before intubation. The registration will be
           for 1 min 1 min before anticipated intubation.

        -  There will also be one skin conductance response per sec registration for 1 min and the
           NRS score, one day postoperatively, when asking the patient about any side effects from
           the study.

      During all defined events, the subject's skin conductance responses will be evaluated using
      the PainMonitor, and the subject will be asked to report pain using the 10 point NRS scale
      when awake. Before intubation when the patient is anesthetized, without stimuli, it is
      defined that the patient has no pain.

      During these events, the number of skin conductance responses/sec will be analyzed in the
      defined time period, and this value will be used for statistical analyses. NRS scores will be
      obtained after the event and the value of the felt pain during the event will be asked for.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Adult cardiac patients prior to, during, and after anesthesia for surgery. The proposed
        pilot study will be conducted at the Acute Clinic, Rikshospitalet - Oslo University
        hospital, Oslo, Norway.