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A multilevel neo-institutional analysis of infection prevention and control in English hospitals: coerced safety culture change?
Despite committed policy, regulative and professional efforts on healthcare safety, little is known about how such macro-interventions permeate organisations and shape culture over time. Informed by neo-institutional theory, we examined how inter-organisational influences shaped safety practices and inter-subjective meanings following efforts for coerced culture change. We traced macro-influences from 2000 to 2015 in infection prevention and control (IPC). Safety perceptions and meanings were inductively analysed from 130 in-depth qualitative interviews with senior- and middle-level managers from 30 English hospitals. A total of 869 institutional interventions were identified; 69% had a regulative component. In this context of forced implementation of safety practices, staff experienced inherent tensions concerning the scope of safety, their ability to be open and prioritisation of external mandates over local need. These tensions stemmed from conflicts among three co-existing institutional logics prevalent in the NHS. In response to requests for change, staff flexibly drew from a repertoire of cognitive, material and symbolic resources within and outside their organisations. They crafted 'strategies of action', guided by a situated assessment of first-hand practice experiences complementing collective evaluations of interventions such as 'pragmatic', 'sensible' and also 'legitimate'. Macro-institutional forces exerted influence either directly on individuals or indirectly by enriching the organisational cultural repertoire
Effects of ÎČ(2)-agonist- and dexamethasone-treatment on relaxation and regulation of ÎČ-adrenoceptors in human bronchi and lung tissue
1. Long-term treatment with ÎČ(2)-adrenoceptor agonists can lead to a decreased therapeutic efficacy of bronchodilatation in patients with obstructive pulmonary disease. In order to examine whether or not this is due to ÎČ-adrenoceptor desensitization, human bronchial muscle relaxation was studied in isolated bronchial rings after pretreatment with ÎČ(2)-adrenoceptor agonists. Additionally, the influence of pretreatment with dexamethasone on desensitization was studied. 2. The effect of ÎČ(2)-agonist incubation alone and after coincubation with dexamethasone on density and affinity of ÎČ-adrenoceptors was investigated by radioligand binding experiments. 3. In human isolated bronchi, isoprenaline induces a time- and concentration-dependent ÎČ-adrenoceptor desensitization as judged from maximal reduction in potency by a factor of 7 and reduction of 73±4% in efficacy of isoprenaline to relax human bronchial smooth muscle. 4. After an incubation period of 60âmin with 100âÎŒmolâl(â1) terbutaline, a significant decline in its relaxing efficacy (81±8%) and potency (by a factor 5.5) occurred. 5. Incubation with 30âÎŒmolâl(â1) isoprenaline for 60âmin did not impair the maximal effect of a subsequent aminophylline response but led to an increase in potency (factor 4.4). 6. Coincubation of dexamethasone with isoprenaline (120âmin; 30âÎŒmolâl(â1)) preserved the effect of isoprenaline on relaxation (129±15%). 7. In radioligand binding experiments, pretreatment of lung tissue for 60âmin with isoprenaline (30âÎŒmolâl(â1)) resulted in a decrease in ÎČ-adrenoceptor binding sites (B(max)) to 64±1.6% (P<0.05), while the antagonist affinity (K(D)) for [(3)H]-CGP-12177 remained unchanged. 8. In contrast, radioligand binding studies on lung tissue pretreated with either dexamethasone (30âÎŒmolâl(â1)) or isoprenaline (30âÎŒmolâl(â1)) plus dexamethasone (30âÎŒmolâl(â1)) for 120âmin did not lead to a significant change of B(max) (160±22.1% vs 142.3±28.7%) or K(D) (5.0ânmolâl(â1) vs 3.5ânmolâl(â1)) compared to the controls. 9. In conclusion, pretreatment of human bronchi with ÎČ-adrenoceptor agonists leads to functional desensitization and, in lung tissue, to down-regulation of ÎČ-adrenoceptors. This effect can be counteracted by additional administration of dexamethasone. Our model of desensitization has proved useful for the identification of mechanisms of ÎČ-adrenoceptor desensitization and could be relevant for the evaluation of therapeutic strategies to counteract undesirable effects of long-term ÎČ-adrenoceptor stimulation