Effect of Locally Administered Morphine and Bupivicaine on Acute and Chronic Postmastectomy Pain
Condition: Acute Pain; Chronic Pain
MeSH terms: Chronic Pain; Acute Pain
Study type: Interventional
Phase: Phase 2

Summary: 
      This study investigate the effect of addition morphine to locally instillation bupivacaine on
      developing chronic neuropathic pain acute postoperative pain after breast cancer surgery and
      on the probability of developing chronic neuropathic pain.
    

Detailed description: 
      Breast cancer is one of the most common cancer diagnoses in women and a significant cause of
      mortality and morbidity worldwide.Surgical treatment indicated in most patients. Persistent
      pain and sensory disturbances following surgery is a significant clinical problem with an
      average prevalence of 20-23.9%. Post-mastectomy chronic pain syndrome (PMPS) is defined as
      pain of neuropathic character located in the area of surgery and/or the ipsilateral arm,
      present at least 4 days per week, and with an average intensity of at least 3 on a numeric
      rating scale from 0 to 10. The pathological mechanisms may be related to patient
      characteristics, surgical technique and adjuvant therapy. Although the genesis of pain is
      multi-factorial, sectioning of the intercostobrachial nerve (a cutaneous branch of T1-2) is
      the nerve lesion diagnosed most often.

      Uncontrolled acute postoperative pain is defined as an important risk factor for the
      development of chronic pain. Local anesthetics have been investigated in cancer breast
      patients through many routes; paravertebral blocks, thoracic epidurals, wound infiltration,
      topical lidocaine patch, and the topical application of EMLA( Eutectic Mixture of Local
      Anesthetics) cream on operation site. Most of above studies suggested a better outcome in
      terms of reduced postoperative pain and improved patient satisfaction.

      Opioids exert a local analgesic effect is based on several observations: • Nociceptive
      afferent nerve fibers contain peripheral opioid receptors which are silent except in the
      presence of local inflammation. • Morphine and its metabolites are largely undetectable
      systemically when applied topically to skin ulcers, suggesting the analgesic effect is local
      • Peripheral opioid injections for local analgesia, such as intra-articular morphine after
      knee surgery, have been found to be effective in several trials. An effective topical opioid
      analgesic that could be applied to inflamed or open skin lesions would be a useful option for
      some patients where other options for pain relief have been exhausted.
    

Intervention name(s): local instillation of morphine to surgical wound
Intervention type(s): Drug
Intervention description(s): comparison between different drug doses effects on pain
Other intervention name(s): morphine sulphate
Intervention MeSH terms: Morphine
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Local morphine; Postmastectomy pain