Clinical Trial: Opioid Induced Hyperalgesia (OIH) Modulation With Propranolol

Study Status: Not yet recruiting
Recruit Status: Not yet recruiting
Study Type: Interventional

Official Title: Opioid Induced Hyperalgesia (OIH) Modulation With Propranolol, in Laparoscopic Abdominal Surgery

Brief Summary:

Opioid Induced Hyperalgesia (OIH) is an entity than has been demonstrated in healthy volunteers and in animal models. Is defined as an increase in the perception to painful stimuli, increasing the opioid requirements and diminishing the pain thresholds to stimuli.

The apparition of OIH is also related to the exposure to opioids during surgery, depending of the dose, the time of exposition and the type of opioid.

This condition can be modulated, specially in the perioperative context. It has been seen in healthy volunteers and in animal models, than the use of propranolol can modulate this phenomena, diminishing the postoperative requirements of analgesia. It is also unknown, the dose of propranolol required to modulate adequately OIH.

The objective of this work is to evaluate the efficacy of propranolol in the modulation of opioid induced hyperalgesia, with lower postoperative requirements of analgesia rescue.


Detailed Summary:

This is a randomized controlled study, comparing 2 interventions with a placebo. The interventions will be use of propranolol, at different doses, to achieve specific plasmatic concentrations.

80 patients will be required to find a difference of 20% in the primary outcome.

The primary outcome to be measured is the postoperative use of opioids in the post anesthesic care unit.

Secondary outcomes, will be the amount of opioids used in the following 24 hours to the surgery, the time to the first dose of analgesia in the post anesthesic care unit, and the change in the pain thresholds, evaluated as pain by pressure and by tactile sensitivity, before and after surgery.

Also, as a secondary outcome, in a group than will not receive the study drug, we will evaluate the temporal changes in opioid induced hyperalgesia, by pain sensitivity measured in the postoperative hours 2, 4 and 24. 10 patients receiving placebo will be part of this additional measures.


Sponsor: Pontificia Universidad Catolica de Chile

Current Primary Outcome: Postoperative opioid use [ Time Frame: 24 hours posterior to surgery ]

Dose of opioid required to manage pain adequately


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Pain thresholds (heat) [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of the threshold to perceive a heat perception as pain
  • Pain thresholds (cold) [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of the threshold to perceive a cold perception as pain
  • Pain thresholds (tactile sensitivity) [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of pain by tactile sensitivity, using the PinPrick system
  • Temporal changes in pain sensibility [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of pain by tactile sensitivity, using the PinPrick system


Original Secondary Outcome:

  • Pain thresholds (heat) [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of the threshold to perceive a heat perception as pain
  • Pain thresholds (cold) [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of the threshold to perceive a cold perception as pain
  • Pain thresholds (tactile sensitivity) [ Time Frame: 24 hours posterior to surgery ]
    Evaluation of pain by tactile sensitivity, using the PinPrick system


Information By: Pontificia Universidad Catolica de Chile

Dates:
Date Received: September 12, 2016
Date Started: October 2016
Date Completion: May 2017
Last Updated: October 26, 2016
Last Verified: October 2016