Efficacy of Fentanyl to Reduce the Time of Severe Postoperative Pain Relief Compared to Morphine
Condition: Postoperative Pain
MeSH terms: Pain, Postoperative
Study type: Interventional
Phase: Phase 3

Summary: 
      Fentanyl is a potent opioid, it is theoretically 100 times more potent that morphine and in
      severe acute postoperative pain acts faster than its congener (morphine ) for pain relief .
      In the literature there is no study that corroborates this theoretical assumption and
      proposes to compare which has fewer adverse effects. This drug produces effects similar to
      those reported for morphine but less magnitude and has the advantage that during the
      postoperative period respiratory depression, antitussive effect , gastrointestinal discomfort
      and physical dependence are manifested in a significantly less degree.

      Trying to solve the management of postoperative pain relief , our objective is to determine
      by controlled clinical trial of superiority if in adult patients undergoing surgery ,
      fentanyl reduces faster qualification time of severe pain to mild pain in the postanesthesia
      care unit compared to morphine.
    

Detailed description: 
      Postoperative pain is a severe problem of high incidence worldwide. According to a systematic
      review of the literature by Dolin et al , the incidence of moderate to severe postoperative
      pain in 41% of patients were found , and of these , only 23% experienced relief of the same (
      1). International Association for Study of Pain defines pain as unpleasant sensory or
      emotional experience associated with actual or potential damage , or described in terms of
      such damage ( 3). The postoperative pain is not only important for to cause suffering or
      unpleasant experience to the patient, but also by involving harmful effects to the body ( 4).
      Thus, the secondary stress to pain triggers the release of a series of hormonal mediators and
      activation of the sympathetic nervous system in conjunction with surgical trauma and previous
      comorbidities of the patient, that cause dysfunction of multiple organ systems , including
      the cardiovascular (5, 6) , GI (7-10) and respiratory ( 11,12 ), among others , increasing
      the incidence of postoperative complications such as myocardial ischemia , atelectasis (
      25-75 % after abdominal surgery) , respiratory infections (pneumonia 1-3 % after cardiac
      surgery ) , ileus , deep vein thrombosis and cognitive dysfunction. Thus increases the
      morbidity and patient recovery is delayed. (5) Similarly it has been observed that
      postoperative pain increases stay in the post anesthesia care unit , readmission for pain
      management, and delayed rehabilitation and reintegration of patients to activities of daily
      living , with the consequent increase in costs (5) . Considering the above arguments , it is
      obvious that timely intervention generates profit problem on multiple levels.

      While the management of postoperative pain should include issues ranging from education to
      the patient prior to its analgesic plan to late recovery period in the post-anesthesia care
      area is crucial. This is because it has been shown that poor control of postoperative pain (
      3) in the early hours is associated with higher levels of pain at 48 hours . There is growing
      interest in the question of why , despite the availability of different drugs and
      technological advances that allow a better understanding of the pathophysiology of pain , has
      not been achieved a greater impact on the incidence of this problem ( 13).

      Opioids are the most important drugs for postoperative pain control. In the post-anesthesia
      care area , especially when faced with a patient with severe or unbearable pain (14,15) , the
      analgesic opioid titration is the most effective strategy for controlling postoperative pain
      ( 16). The most studied and used today opioid is morphine, which by its pharmacokinetic
      characteristics provides an important balance between speed of onset and maintenance of
      analgesia ( 17). However, there are other alternatives for analgesic titration , such as
      fentanyl , which has favorable pharmacokinetics to have a faster response and thus may
      shorten the time needed to decrease pain from severe to mild ( 14,15). There are comparative
      studies between fixed-dose fentanyl and morphine in the emergency services and some
      preliminary tests in the recovery area (18,19). The most recent of analgesic titration trials
      comparing appropriate doses of opioids to patient weight which would improve its efficacy and
      safety ( 20). The tests that are known to have used fentanyl and morphine compared fixed-dose
      and 10 minute intervals .

      Fentanyl is a potent opioid, it is theoretically 100 times more potent that morphine and in
      severe acute postoperative pain acts faster than its congener (morphine ) for pain relief .
      In the literature there is no study that corroborates this theoretical assumption and
      proposes to compare which has fewer adverse effects. This drug produces effects similar to
      those reported for morphine but less magnitude and has the advantage that during the
      postoperative period respiratory depression, antitussive effect , gastrointestinal discomfort
      and physical dependence are manifested in a significantly less degree.

      Trying to solve the management of postoperative pain relief , our objective is to determine
      by controlled clinical trial of superiority if in adult patients undergoing surgery ,
      fentanyl reduces faster qualification time of severe pain to mild pain in the postanesthesia
      care unit compared to morphine.
    

Intervention name(s): Fentanyl; Morphine
Intervention type(s): Drug; Drug
Intervention description(s): The nurse will administer 1 ug per kg during 5 seconds when the patient complain of pain (visual analog scale, VAS, ≥7). Immediately with the onset of drug administration a timer started; every 5 minutes the researcher assess the EVA and the drug will be administered if VAS > 3, until the patient manifests as a lower pain VAS ≤ 3 (mild). The nurse in charge in the PACU will manage the drug and will take 100 ug of fentanyl which is diluted in 10 mL of normal saline leaving a 10μg per ml concentration, are not labeled and for the physical and chemical characteristics of both drugs (colorless) risks of unblinded is minimized.; The nurse will administer 0,1 mg per kg during 5 seconds when the patient complain of pain (visual analog scale, VAS, ≥7). Immediately with the onset of drug administration a timer started; every 5 minutes the researcher assess the EVA and the drug will be administered if VAS > 3, until the patient manifests as a lower pain VAS ≤ 3 (mild). The nurse in charge in the PACU will manage the drug and will take 10 mg of morphine which is diluted in 10 mL of normal saline leaving a 1 mg per ml concentration, are not labeled and for the physical and chemical characteristics of both drugs (colorless) risks of unblinded is minimized.
Other intervention name(s): Opioids; Opioids
Intervention MeSH terms: Fentanyl; Morphine; Analgesics, Opioid
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Severe postoperative pain; Morphine; Fentanyl; Time to titration of pain; Pain and PACU; Anesthesiology