Successful paediatric renography does not require sedation.

INTRODUCTION: Sedation is often used to optimise ren-ography in children < 3 years, but it requires continuous monitoring. METHODS: We discontinued routine use of chloral hydrate sedation of patients undergoing renography, and introduced that children < 2 years were placed in a child immobiliser for nuclear examinations at the Department of Paediatrics before being transported for renography. In addition, children < 3 years were offered melatonin, which is not a sedative. Chloral hydrate was given only if parents wanted sedation. We analysed the results from a consecutive series of patients undergoing renography from August 2010 to December 2015 and compared data from those who had been administered choral hydrate sedation with those who had received no sedation. RESULTS: Renography was unaccomplished in 10% (3/30) of the choral hydrated sedated children and in 11% (54/512) of the non-sedated children (p = 0.83). Uncooperative children resulted in failed renography in 0% (0/3) and 39% (21/54) of cases, respectively (p = 0.46). Patients placed in a child immobiliser at the Department of Paediatrics had the greatest probability of achieving successful renography (p = 0.0013), the shortest renography procedure duration irrespective of melatonin use (p = 0.0001) and the lowest risk of a procedure duration > 60 minutes (p = 0.0004). CONCLUSIONS: Renography can be performed without sedation. We recommend that children < 2 years be placed in a child immobiliser at the Department of Paediatrics before being transported for renography. Additional studies are needed to investigate the effects of melatonin. FUNDING: none. TRIAL REGISTRATION: not relevant.

ReN 1869, a novel tricyclic antihistamine, is active against neurogenic pain and inflammation.

The tricyclic compound (R)-1-(3-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)-1-propyl)-3-piperidine carboxylic acid (ReN 1869) is a novel, selective histamine H(1) receptor antagonist. It is orally available, well tolerated, easily enters the central nervous system (CNS) but no adverse effects are seen in mice at 300 mg/kg. ReN 1869 at 0.01-10 mg/kg is antinociceptive in tests of chemical nociception in rodents (formalin, capsaicin, phenyl quinone writhing) but not in thermal tests (hot plate and tail flick). ReN 1869 amplifies the analgesic action of morphine but does not show tolerance after chronic dosing. Moreover, the compound is effective against inflammation of neurogenic origin (antidromic nerve stimulation, histamine-evoked edema) but not in carrageenan-induced inflammation. We suggest that ReN 1869, via H(1) blockade, counteracts the effect of histamine liberated from activated mast cells and inhibits pain transmission in the dorsal spinal cord. ReN 1869 represents a new class of antihistamines with pain-relieving properties that probably is mediated centrally through histamine H(1) receptors but alternative mechanisms of action cannot be excluded.