title: Opioid switching and burst ketamine to improve the opioid response in patients with movement-related pain due to bone metastases.
abstract: OBJECTIVE
  To improve opioid repsonse in patients with movement-related pain by using opioid switching adding a burst of ketamine.
  
  
  METHODS
  Two patients with incident bone pain who had adverse effects with increasing doses of opioids were switched to methadone and a burst of 100 mg/d of ketamine for 2 consecutive days was added.
  
  
  RESULTS
  Basal pain and pain on movement significantly improved.
  
  
  CONCLUSIONS
  The development of breakthrough pain due to movement (incident pain), associated with bone metastases is so rapid that no medication as needed has such a short onset to parallel this temporal pattern of pain firing. Experimental studies have shown that bone metastases are characterized by a specific pattern of spinal hyperexcitation requiring higher doses of opioids. Optimization of basal opioid regimen may improve mobilization. However, adverse effects may more likely occur. The role of opioid switching and burst ketamine to further improve the opioid response has never been assessed in this context. Further studies in animals could confirm these preliminary data, with specific design to parallel this clinical context.
authors.affiliation: Pain Relief and Palliative Care Unit, La Maddalena Cancer Center, Via San Lorenzo Colli 312, 90146 Palermo, Italy. terapiadeldolore@lamaddalenanet.it
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Mercadante
authors.forename: Patrizia
authors.initials: P
authors.lastname: Villari
authors.forename: Patrizia
authors.initials: P
authors.lastname: Ferrera
authors.forename: Edoardo
authors.initials: E
authors.lastname: Arcuri
authors.forename: Fabrizio
authors.initials: F
authors.lastname: David
mesh_terms: D000701:Analgesics, Opioid / Q000627:therapeutic use*; D000778:Anesthetics, Dissociative / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000150:complications* / Q000556:secondary; D006801:Humans; D007649:Ketamine / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000188:drug therapy / Q000209:etiology*; D010146:Pain / Q000188:drug therapy* / Q000209:etiology
chemical_list: D000701:Analgesics, Opioid; D000778:Anesthetics, Dissociative; D007649:Ketamine