Controlling Phlebotomy Volume Diminishes PICU Transfusion: Implementation Processes and Impact.

BACKGROUND AND OBJECTIVES: Phlebotomy excess contributes to anemia in PICU patients and increases the likelihood of red blood cell transfusion, which is associated with risk of adverse outcomes. Excessive phlebotomy reduction (EPR) strategies may reduce the need for transfusion, but have not been evaluated in a PICU population. We hypothesized that EPR strategies, facilitated by implementation science methods, would decrease excess blood drawn and reduce transfusion frequency. METHODS: Quantitative and qualitative methods were used. Patient and blood draw data were collected with survey and focus group data to evaluate knowledge and attitudes before and after EPR intervention. The Consolidated Framework for Implementation Research was used to interpret qualitative data. Multivariate regression was employed to adjust for potential confounders for blood overdraw volume and transfusion incidence. RESULTS: Populations were similar pre- and postintervention. EPR strategies decreased blood overdraw volumes 62% from 5.5 mL (interquartile range 1-23) preintervention to 2.1 mL (interquartile range 0-7.9 mL) postintervention (P < .001). Fewer patients received red blood cell transfusions postintervention (32.1% preintervention versus 20.7% postintervention, P = .04). Regression analyses showed that EPR strategies reduced blood overdraw volume (P < .001) and lowered transfusion frequency (P = .05). Postintervention surveys reflected a high degree of satisfaction (93%) with EPR strategies, and 97% agreed EPR was a priority postintervention. CONCLUSIONS: Implementation science methods aided in the selection of EPR strategies and enhanced acceptance which, in this cohort, reduced excessive overdraw volumes and transfusion frequency. Larger trials are needed to determine if this approach can be applied in broader PICU populations.

Gonadal hormones modulate the display of conditioned defeat in male Syrian hamsters.

It has been widely reported that gonadal hormones influence the display of aggression in Syrian hamsters; conversely, much less is known about whether gonadal hormones modulate submissive/defensive behaviors in these animals. Following social defeat, male hamsters no longer display normal territorial aggression but instead display submissive/defensive behavior in the presence of a smaller opponent, a phenomenon we have termed conditioned defeat (CD). The purpose of the present study was to examine the effect of gonadal hormones on the display of CD in male hamsters. In Experiment 1, males were castrated or sham-operated. The castrated males were significantly more submissive following social defeat relative to their intact counterparts. The increased submissive behavior in the castrated males during CD testing was particularly surprising, given the fact that they were attacked significantly less during CD training. In Experiment 2a, males were castrated and given hormone replacement. Castrated males treated with testosterone or dihydrotestosterone displayed significantly less submissive behavior following social defeat than did those treated with cholesterol or estradiol. Finally, in Experiment 2b, there was no effect of hormone replacement on aggressive behavior in non-defeated hamsters suggesting that the decrease in submissive behavior in males treated with dihydrotestosterone or testosterone is specific to being previously defeated. Taken together the data indicate that the presence of androgens reduces the display of submission in defeated male hamsters. More importantly, these findings suggest that androgens may have a protective effect against the development of depression-like or anxiety-like behaviors following exposure to an ethologically relevant stressor.

Lesions of structures showing FOS expression to cat presentation: effects on responsivity to a Cat, Cat odor, and nonpredator threat.

Exposure of rats to a cat elicits Fos activity in a number of brain areas or structures. Based on hodological relationships of these, Canteras has proposed a medial hypothalamic defense system, with input from several forebrain sites. Both electrolytic and neurotoxic lesions of the dorsal premammillary nucleus, which shows the strongest Fos response to cat exposure, produce striking decrements in a number of defensive behaviors to a cat or to cat odor stimuli, but do not have a major effect on either postshock freezing, or responsivity to the odor of a female in estrus. Neurotoxic lesions of the medial amygdala produce decrements in defensiveness to predator stimuli, particularly odor stimuli, that are consistent with a view of this structure as involved with allomonal cues. While dorsal hippocampal lesions had little effect on responsivity to predator stimuli, neurotoxic lesions of the ventral hippocampus reduced freezing and enhanced a variety of nondefensive behaviors to both cat odor and footshock, with similar reductions in defensiveness during context conditioning tests for cat odor, cat exposure and footshock. These results support the view that the dorsal premammillary nucleus is strongly and selectively involved in control of responsivity to predator stimuli. Structures with important input into the medial hypothalamic defense system appear also to be functionally involved with antipredator defensive behaviors, and these lesion studies may suggest specific hypotheses as to the particular defense functions of different areas.