"I want to be there. I have to be there.": Parents' perceived barriers and facilitators to bedside presence in the pediatric intensive care unit.

Introduction: Parental presence at the bedside during a stressful pediatric intensive care unit (PICU) admission may improve child comfort, reduce parental anxiety, and enable family engagement. We performed this study to identify factors that parents perceive impact their capability, opportunity, and motivation to be at the bedside in PICU. Methods: We conducted a qualitative descriptive study using semi-structured interviews based on the Theoretical Domains Framework (TDF). We included parents of children admitted to the PICU for at least 24 h at IWK Health in Nova Scotia, Canada. Interviews were coded independently by two researchers using a directed content approach based on the TDF. We generated themes and subthemes, with the subthemes identified as factors impacting parental presence, and assigned TDF domains to each of the subthemes. Results: Fourteen primary caregivers (8 mother figures, 6 father figures) participated in 11 interviews. The factors associated with parental presence were captured by 6 themes: Understanding the Medicalized Child; Maintaining the Parent Role; Life Beyond the Hospital; Parental Intrinsic Responses and Coping; Support Structures; and The PICU Environment. Fifty-two barriers and enablers were identified within 13 TDF domains; 10 TDF domains were determined to be relevant to parental presence, which may be used to guide design of future interventions. Participants emphasized the importance of self-care to enable them to remain physically at their child's bedside and to be engaged in their care. Conclusions: Parents perceive multiple factors within 6 themes act as barriers or enablers to presence with their critically ill child in the PICU. Guided by relevant TDF domains, interventions may be designed to optimize presence, particularly engaged presence, which may improve health-related outcomes of children and their parents.

Nitric Oxide Acts in the Rat Dorsomedial Hypothalamus to Increase High Fat Food Intake and Glutamate Transmission.

The dorsomedial nucleus of the hypothalamus (DMH) plays an important role in the regulation of energy intake and expenditure. Numerous appetite-regulatory signals present in the DMH, including nitric oxide (NO) and endogenous cannabinoids (eCBs), act to regulate food intake, but whether these signals are involved in regulating high fat food intake remains unknown. We therefore asked whether NO and eCBs, administered alone or in combination, would influence the consumption of high fat food in rats. We implanted bilateral guide cannulas in the DMH of young, male Sprague-Dawley rats for microinjection of vehicle, NO (via the precursor l-arginine), the eCB 2-arachidonylglycerol (2-AG), or a combination of the two signals. Following the intrahypothalamic injections, both high fat food intake and body weight were measured for two hours at which point brains were removed and sectioned to confirm cannula placement in the DMH. Here we show that l-arginine significantly increases high fat food intake when administered into the DMH. This effect is abolished in the presence of 2-AG, which alone has no effect on high fat food intake or body weight. The l-arginine-induced increase in high fat food intake is dependent on NO synthesis, as it is prevented with the NO synthase inhibitor, l-NAME. We also demonstrate that l-arginine increases glutamate transmission onto DMH neurons, an effect that also requires NO synthesis and is abolished with 2-AG. Together, these data indicate that NO acts in the DMH to regulate the consumption of high fat food, possibly by enhancing glutamate signaling at DMH synapses.

Stereotaxic surgery for implantation of guide cannulas for microinjection into the dorsomedial hypothalamus in young rats.

Stereotaxic surgery to implant guide cannulas into the rodent brain is a frequently used technique to deliver drugs to targeted brain regions in awake, freely moving animals. There are limited reports, however, of central injections in young animals, and no information on cannula implantation for drug administration into the dorsomedial hypothalamus (DMH) in young rats. Our protocol describes a simple and successful method for implanting guide cannulas in the brains of young, male Sprague-Dawley rats and outlines newly developed stereotaxic coordinates to accurately target the dorsomedial hypothalamus. •Stereotaxic surgical procedure for guide cannula implantation in the DMH in young rats.•Development of stereotaxic coordinates of the DMH in young rats.•Microinjection of drugs into the young rat brain.

2-arachidonylglycerol interacts with nitric oxide in the dorsomedial hypothalamus to increase food intake and body weight in young male rats.

The dorsomedial nucleus of the hypothalamus (DMH) is an important appetite regulatory center in the brain. In young rats, neural communication in the DMH is modulated by two interacting signals: endocannabinoids (eCBs) and nitric oxide (NO), both of which are known to modulate appetite. It remains unknown, however, whether eCBs and NO interact in the DMH to regulate food intake and body weight in young rats. We developed stereotaxic coordinates for the DMH in young, male Sprague-Dawley rats and conducted surgeries to implant bilateral guide cannulas for microinjection of vehicle, eCBs [2-arachidonylglycerol (2-AG) or anandamide]; NO (via the precursor l-arginine), or a combination of the two, with and without prior subcutaneous injections of drugs to block cannabinoid receptors or NO synthesis. Food intake and body weight of animals were measured two hours following the injection and brains were subsequently removed and sliced to verify placement of the cannulas relative to the DMH. Here we show that 2-AG, when administered in combination with l-arginine, significantly increased food intake and body weight, an effect that required type I cannabinoid receptors and NO synthesis. 2-AG and l-arginine had no effect on food intake or body weight when administered into the DMH independently. Anandamide also failed to affect these parameters when administered alone or with l-arginine. Together, these data suggest that 2-AG and NO interact in the DMH to increase food intake in young male rats and provide insight into a possible mechanism by which 2-AG increases appetite.