Fig. 1From: Intravenous patient-controlled analgesia: in vitro stability profiles of mixtures containing fentanyl, hydromorphone, oxycodone, nefopam, ondansetron, and ramosetronChromatograms from samples taken immediately after preparation of the B mixtures. a Mixture 1B. b Mixture 2B. c Mixture 3B. d Mixture 4BBack to article page