title: Ketamine analgesic effect by continuous intravenous infusion in refractory cancer pain: considerations about the clinical research in palliative care.
abstract: BACKGROUND
  The literature has described the use of ketamine as an adjuvant treatment for opioid-refractory cancer pain. None of these studies have used the drug in a palliative care patient population.
  
  
  OBJECTIVE
  The primary objective of the study was to assess the efficacy of continuous intravenous infusion of ketamine in patients suffering from cancer pain refractory to opiates who had been admitted to palliative care units. Secondary objectives were to assess patients' satisfaction with and tolerance of ketamine.
  
  
  METHODS
  A randomized, double-blind, placebo-controlled study was designed, and the study setting included seven French adult palliative care units. Inclusion criteria were age ≥18 years, and cancer pain refractory to standard opiates. Evaluations were conducted at randomization (baseline), at ketamine or placebo introduction time (T0), and at 2 hours (T1), 24 hours (T2), and 48 hours (T3) after T0. The primary evaluation criterion was pain efficacy assessed using a patient self-rated Numeric Pain Intensity Scale (NPIS) at T1. The main secondary evaluation criteria were daily morphine dose, symptom evaluation (Edmonton Symptom Assessment Scale [ESAS]), and patient satisfaction (Pain Treatment Satisfaction Scale [PTSS]).
  
  
  RESULTS
  Twenty patients were analyzed (11 received ketamine and 9 received placebo). Self-reported pain did not differ between the two groups, as the symptoms continued to evolve during the study period. The tolerance for ketamine was satisfactory.
  
  
  CONCLUSIONS
  The present study did not confirm the efficacy of the ketamine-morphine combination in refractory cancer pain. The results suggest that specific populations could be "good responders" for this therapeutic approach. Further studies should be performed that take into account the difficulties of conducting clinical research in the palliative care context.
authors.affiliation: Service d'Oncologie Médicale Adulte et de Soins Palliatifs, CHU Timone, APHM, Université de la Méditerranée, Marseille, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Salas
authors.forename: Matthieu
authors.initials: M
authors.lastname: Frasca
authors.forename: Brigitte
authors.initials: B
authors.lastname: Planchet-Barraud
authors.forename: Benoît
authors.initials: B
authors.lastname: Burucoa
authors.forename: Monique
authors.initials: M
authors.lastname: Pascal
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Lapiana
authors.forename: Raymond
authors.initials: R
authors.lastname: Hermet
authors.forename: Claudine
authors.initials: C
authors.lastname: Castany
authors.forename: Frédéric
authors.initials: F
authors.lastname: Ravallec
authors.forename: Anderson
authors.initials: A
authors.lastname: Loundou
authors.forename: Pascal
authors.initials: P
authors.lastname: Auquier
authors.forename: Florence
authors.initials: F
authors.lastname: Duffaud
authors.forename: Karine
authors.initials: K
authors.lastname: Baumstarck
mesh_terms: D000328:Adult; D000368:Aged; D000700:Analgesics / Q000008:administration & dosage*; D035843:Biomedical Research; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007649:Ketamine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000503:physiopathology*; D017063:Outcome Assessment, Health Care; D010148:Intractable Pain / Q000188:drug therapy*; D010166:Palliative Care
chemical_list: D000700:Analgesics; D007649:Ketamine