Effects of propofol on cerebral oxygenation during cardiopulmonary bypass in children

PURPOSE: Neurologic complications occur following cardiopulmonary bypass surgery. We conducted a randomized, controlled, single-blind study to determine the effect of propofol on the redox status of cytaa3, and to evaluate its potential for decreasing neurologic complications. METHODS AND MATERIALS: Twenty-four children (median age: 3.3 yr; median weight: 14.4 kg) scheduled for elective cardiopulmonary bypass surgery were assigned to either the experimental group (Group P, given sufficient propofol to eliminate brain electrical activity as measured on EEG (i.e. burst suppression)) or the control group (Group C, no propofol). Near infrared spectroscopy data were collected at one-second intervals throughout the surgical procedures. Pre- and postoperative neurologic examinations were completed by a physician blinded to the group to which the patient was assigned. Change in cytochrome aa3 data at 10-min intervals (10, 20, 30, 40 min) following start of bypass were compared between groups by repeated measures analysis of variance. RESULTS: The patterns of change in redox state of cytochrome were different between the two groups (P < 0.002). The pattern of change within Group P was similar to that in hypothermic patients in Group C. There were correlations between change in cytaa3 redox status and temperature in the control subjects. There were no gross neurologic complications in either group. CONCLUSIONS: Propofol appears to stabilize the energy supply/demand equilibrium of the brain during cardiopulmonary bypass surgery and thus theoretically could reduce the incidence or severity of neurologic complications.     

Cerebral asymmetry and the development of early infantile autism

Two experiments involving listening preferences of autistic and normal subjects were conducted to test the hypothesis that the right cerebral hemisphere is more active than the left hemisphere in autistic children. Results showed that when given a choice between verbal and musical material, the autistic children preferred music, while normal children showed no preference. Secondly, autistic children listened to both types of material predominantly with the left ear. Although normal subjects showed greater variation among themselves, they tended to listen to music more often with the left ear and to listen to verbal material more often with the right. These results support the notion that some autistic children are predominantly righthemisphere processors.This research was supported in part by a Minor Research Grant and a Summer Stipend from the Faculty of Arts, York University. Parts of this material have been presented at the 1977 meetings of the Society for Research in Child Development and the National Conference of the Canadian Society for Autistic Children. The author wishes to thank Patricia Crawford, Peter Morden, Susan B. Sussman, and Reva Tankle for their invaluable assistance on this project.     

Getting ready for user involvement in a systematic review

Objective  This paper aims to support the critical development of user involvement in systematic reviews by explaining some of the theoretical, ethical and practical issues entailed in 'getting ready' for user involvement.
Background  Relatively few health or social care systematic reviews have actively involved service users. Evidence from other research contexts shows that user involvement can have benefits in terms of improved quality and outcomes, hence there is a need to test out different approaches in order to realize the benefits of user involvement and gain a greater understanding of any negative outcomes.
Design  Setting up a service-user reference group for a review of user involvement in nursing, midwifery and health visiting research involved conceptualizing user involvement, developing a representation framework, identifying and targeting service users and creating a sense of mutuality and reciprocity.
Setting and participants  Recruitment was undertaken across England by two researchers. Members from 24 national consumer organizations were selected to participate in the review.
Main variables studied  Learning was gained about finding ways of navigating consumer networks and organizations, how best to communicate our goals and intentions and how to manage selection and 'rejection' in circumstances where we had stimulated enthusiasm.
Results and conclusions  Involving service users helped us to access information, locate the findings in issues that are important to service users and to disseminate findings. User involvement is about relationships in social contexts: decisions made at the early conceptual level of research design affect service users and researchers in complex and personal ways.