title: Inter- and intraindividual variability in ketamine dosage in repetitive invasive procedures in children with malignancies.
abstract: Midazolam/ketamine sedation has been used successfully in children undergoing painful invasive procedures. The authors prospectively assessed inter- and intra-individual variability in ketamine dosage for sedation in repetitive invasive procedures in children with malignancies. A total of 92 invasive procedures (58 lumbar punctures, 34 bone marrow biopsies; range: 2-9 procedures/patient) were performed on 25 children (median age: 12 years). Intravenous sedation consisted of 0.1 mg midazolam/kg and 0.5-1.0 mg ketamine/kg. Incremental dosages of ketamine (0.33 mg/kg) were given if necessary to achieve or maintain deep sedation. Primary outcome measure was the inter- and intraindividual ketamine dosage required to achieve adequate sedation; secondary outcome measures were the number of procedures with adequate sedation (Ramsay score of > 4), the number of adverse side effects, and the need for therapeutic interventions. All 92 invasive procedures were completed with satisfactory sedation levels in 88 procedures (95.7%). There was a great inter- and intraindividual variability in ketamine dosage required to achieve or maintain adequate sedation. In 12% of procedures side effects were seen, which required no or only minor interventions. Due to great inter- and intraindividual differences, ketamine dosage should be titrated toward the desired level of sedation. Thus, ketamine can be adjusted to the individual's need while achieving adequate sedation.
authors.affiliation: University Children's Hospital, University of the Saarland, Kirrbergerstr. 66421 Homburg, Germany. sascha.meyer@uniklinik-saarland.de
authors.forename: Sascha
authors.initials: S
authors.lastname: Meyer
authors.forename: Schahin
authors.initials: S
authors.lastname: Aliani
authors.forename: Norbert
authors.initials: N
authors.lastname: Graf
authors.forename: Sven
authors.initials: S
authors.lastname: Gottschling
mesh_terms: D000293:Adolescent; D000778:Anesthetics, Dissociative / Q000008:administration & dosage*; D001706:Biopsy / Q000009:adverse effects; D001856:Bone Marrow Examination / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D003949:Diagnostic Techniques, Surgical; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007223:Infant; D007649:Ketamine / Q000008:administration & dosage*; D008297:Male; D009369:Neoplasms / Q000473:pathology*; D010146:Pain / Q000209:etiology / Q000517:prevention & control; D013129:Spinal Puncture / Q000009:adverse effects; D017186:Titrimetry
chemical_list: D000778:Anesthetics, Dissociative; D007649:Ketamine