[Design and evaluation of the quality of information written for scanner and magnetic resonance imaging in neuropediatrics]. / Conception et évaluation de la qualité d'une information écrite sur le scanner et l'imagerie par résonance magnétique en neuropédiatrie.

INTRODUCTION: We designed written information concerning two medical imaging techniques: the computed tomography scanner and the magnetic resonance imaging (MRI), and we evaluated the quality of the information in particular its readability. METHODS: Written information concerning scanner and MRI were elaborate starting from a reference frame based on a lexicon of the good practices. The written information sheets were initially reviewed by eight doctors, 45 nurses and by 26 couples of parents of hospitalized children, and finally by the communication and juridical services of our hospital. They were asked to improve the lexico-syntactic readability in order to increase the comprehension of the written information. Seventy-two couples of parents of hospitalized children who had not taken part of the protocol before evaluated the final version of the documents. The quality of the documents was evaluated using the scores of readability of Flesch and the Flesch-Kincaid, and a questionnaire of comprehension, managed before and after the delivery of written information. RESULTS: A total of 144 persons participated in the study. The number of right answers after reading written information increased by 38 % and by 35 % for the scanner and MRI information's respectively. Flesch and Flesch-Kincaid scores were not improved in the revised version of the written information compared to the first version. CONCLUSION: Although readability scores for information sheets were low, our results suggest that they brought information, which contributed to a better understanding of these two medical imaging techniques by parents.

Effect of alpha-adrenoceptor blockade on the 0.4 Hz sympathetic rhythm in conscious rats.

1. The present study examined the origin of the 0.4 Hz rhythm in renal sympathetic nerve activity (RSNA) in rats. It was anticipated that, after elimination of 0.4 Hz oscillations of arterial pressure (AP) by alpha-adrenoceptor blockade, the persistence or disappearance of a 0.4 Hz rhythm in RSNA would point to an endogenous (central oscillator) or baroreflex origin, respectively. 2. Arterial pressure and RSNA were recorded in seven conscious rats, before and after acute alpha-adrenoceptor blockade with phentolamine (5 mg/kg, i.v.). In each condition, power and coherence spectra were calculated over 15 min periods of rest. 3. In control conditions, highly coherent AP and RSNA oscillations were observed near 0.4 Hz. After phentolamine administration, spectral power in the mid-frequency (0.27-0.74 Hz) band was significantly reduced for both AP and RSNA and maximum power was shifted towards 0.7 Hz. 4. The disappearance of the RSNA rhythm at 0.4 Hz after phentolamine administration favours the hypothesis of a baroreflex origin. The new oscillation near 0.7 Hz can derive either from the activity of a previously unrecognized central oscillator or from a faster feedback mechanism involving cotransmitters of noradrenaline acting with shorter time constants (e.g. ATP).