Differential contributions of intra-cellular and inter-cellular mechanisms to the spatial and temporal architecture of the suprachiasmatic nucleus circadian circuitry in wild-type, cryptochrome-null and vasoactive intestinal peptide receptor 2-null mutant mice.

To serve as a robust internal circadian clock, the cell-autonomous molecular and electrophysiological activities of the individual neurons of the mammalian suprachiasmatic nucleus (SCN) are coordinated in time and neuroanatomical space. Although the contributions of the chemical and electrical interconnections between neurons are essential to this circuit-level orchestration, the features upon which they operate to confer robustness to the ensemble signal are not known. To address this, we applied several methods to deconstruct the interactions between the spatial and temporal organisation of circadian oscillations in organotypic slices from mice with circadian abnormalities. We studied the SCN of mice lacking Cryptochrome genes (Cry1 and Cry2), which are essential for cell-autonomous oscillation, and the SCN of mice lacking the vasoactive intestinal peptide receptor 2 (VPAC2-null), which is necessary for circuit-level integration, in order to map biological mechanisms to the revealed oscillatory features. The SCN of wild-type mice showed a strong link between the temporal rhythm of the bioluminescence profiles of PER2::LUC and regularly repeated spatially organised oscillation. The Cry-null SCN had stable spatial organisation but lacked temporal organisation, whereas in VPAC2-null SCN some specimens exhibited temporal organisation in the absence of spatial organisation. The results indicated that spatial and temporal organisation were separable, that they may have different mechanistic origins (cell-autonomous vs. interneuronal signaling) and that both were necessary to maintain robust and organised circadian rhythms throughout the SCN. This study therefore provided evidence that the coherent emergent properties of the neuronal circuitry, revealed in the spatially organised clusters, were essential to the pacemaking function of the SCN.

A quality improvement approach to reducing use of meperidine.

BACKGROUND: In 1991 the University of Wisconsin Hospital and Clinics formed a pain management QI team whose goal was to improve pain management through education, outcome monitoring, and the development of programs intended to improve clinical practice. Longitudinal monitoring mechanisms were established to audit medical records and survey patients to examine both staff practice patterns and patient outcomes. The QI team targeted use of meperidine, one of the most widely used opioid analgesics for the treatment of moderate to severe pain, which is now discouraged as a first-line agent for most painful conditions. IMPLEMENTING THE QI PROCESS: A QI process was implemented using a traditional plan-do-check-act (PDCA) model, resulting in a successful and sustained reduction of inappropriate meperidine use. A cause-and-effect diagram helped highlight the multiple factors contributing to the drug's overuse and was used to prioritize targets for action. A flow chart helped to uncover some of the interrelationships between the myths about meperidine and the resultant customary prescribing and administration practices. While most of the strategies were implemented in 1996 (formulary guideline release, change in stock supply and physician orders, staff education and feedback), a significant impact in practice was not seen until late 1997. Ongoing tracking and feedback loops were established to ensure continued low use of meperidine. CONCLUSION: Use of a QI approach in pain management has been shown to affect the visibility of pain as a clinical priority, enhance interdisciplinary collaboration, facilitate the implementation of clinical guidelines at the bedside, and improve the quality of care for patients.

A nurse-run inpatient pain consultation service.

As hospitals across the country work to improve pain management in the face of ever-shrinking resources, one challenge that must be addressed is the delineation of specialized pain management services. Although pain management is an interdisciplinary process, nurses are in a unique position to provide leadership in both the organization and delivery of clinical services. This article describes the development and 2-year experience of a nurse-run inpatient pain management consultation service in an academic tertiary care hospital. The structure of the service, and nature and volume of consults is discussed along with recommendations for institutions considering this strategy.