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1.
Paediatr Anaesth ; 32(8): 926-936, 2022 08.
Article in English | MEDLINE | ID: mdl-35445776

ABSTRACT

BACKGROUND: Failure to complete surgery within the scheduled timeframe impairs operating room efficiency leading to patient dissatisfaction and unplanned labor costs. We sought to improve timely completion (within 30 min of scheduled time) of first-case spine fusion surgery (for idiopathic scoliosis) from a baseline of 25%-80% over 12 months. We also targeted timely completion of perioperative stages within predetermined target completion times. METHODS: The project was conducted in three overlapping phases over 16 months. A simplified process map outlining five sequential perioperative stages, preintervention baselines (N = 24) and time targets were defined. A multidisciplinary team conducted a series of tests of change addressing the aims. The key drivers included effective scheduling, team communications, family engagement, data collection veracity, standardized pathways, and situational awareness. Data collected by an independent data collector and from electronic medical records were analyzed using control charts and statistical process control methods. RESULTS: Post-intervention, timely case completion increased from 25% to 68% (N = 49) (95% CI 15.1-62.7), (p = 0.003) and was sustained (N = 14). Implementation of prediction model for case-scheduling decreased difference between scheduled and actual case end-time (33 vs. 53 min [baseline]) and variance [lower/upper control limits ([-26, 51] vs. [-109, 216] min [baseline]). Average start time delay decreased from 6 to 2 min and on-time surgical starts improved from 50% to 70% (95% CI 3.2-41.6%). Timely completion increased for anesthesia induction (60% to 85%), surgical procedure (26% to 48%) and emergence from anesthesia (44% to 80%) but not for intraoperative patient preparation (30% to 25%) perioperative stages. Families reported satisfaction with preoperative processes (N = 14), and no untoward intraoperative safety events occurred. CONCLUSIONS: Application of QI methodology reduced time variation of several tasks and improved timely completion of spine surgery. Beyond the study period, sustained team behavior, adaptive changes, and vigilant monitoring are imperative for continued success.


Subject(s)
Operating Rooms , Spinal Fusion , Anesthesia, General/methods , Efficiency , Efficiency, Organizational , Humans , Quality Improvement
2.
Pediatr Qual Saf ; 5(4): e284, 2020.
Article in English | MEDLINE | ID: mdl-32766484

ABSTRACT

INTRODUCTION: Overutilization of point-of-care (POC) testing may reduce the overall value of care due to high-cost cartridges, need for staff training, and quality assurance requirements. METHODS: The Diagnostic Stewardship group at Cincinnati Children's Hospital Medical Center assembled a multidisciplinary team to reduce the use of POC blood gas testing by 20% in the pediatric intensive care unit (PICU). Key drivers of test overutilization included poor knowledge of cost, concern with testing turnaround time, and a lack of a standard definition of when a POC test was appropriate. We calculated weekly the outcome measure of POC blood gas tests per PICU patient-day and a balancing measure of blood gas result turnaround time using data extracted from the electronic medical record. Interventions focused on staff education, the establishment of a standard practice guideline for the use of POC testing, and improving turnaround time for laboratory blood gas testing. RESULTS: Over the baseline period starting July 2016, a median of 0.94 POC blood gas tests per PICU patient-day was ordered. After initial staff training, the rate was reduced to 0.60 tests per PICU patient-day and further reduced to 0.41 tests per PICU patient-day after a formal policy change was adopted. We have sustained this rate for 15 months through June 2018. Institutional direct cost savings were estimated to be $19,000 per year. CONCLUSIONS: Our improvement initiative was associated with a significant and rapid reduction in the use of POC testing in the PICU. Interventions focused on cost awareness, and a formal guideline helped establish a consensus around appropriate utilization.

3.
Proc Natl Acad Sci U S A ; 114(37): E7670-E7678, 2017 09 12.
Article in English | MEDLINE | ID: mdl-28847944

ABSTRACT

Do corals form their skeletons by precipitation from solution or by attachment of amorphous precursor particles as observed in other minerals and biominerals? The classical model assumes precipitation in contrast with observed "vital effects," that is, deviations from elemental and isotopic compositions at thermodynamic equilibrium. Here, we show direct spectromicroscopy evidence in Stylophora pistillata corals that two amorphous precursors exist, one hydrated and one anhydrous amorphous calcium carbonate (ACC); that these are formed in the tissue as 400-nm particles; and that they attach to the surface of coral skeletons, remain amorphous for hours, and finally, crystallize into aragonite (CaCO3). We show in both coral and synthetic aragonite spherulites that crystal growth by attachment of ACC particles is more than 100 times faster than ion-by-ion growth from solution. Fast growth provides a distinct physiological advantage to corals in the rigors of the reef, a crowded and fiercely competitive ecosystem. Corals are affected by warming-induced bleaching and postmortem dissolution, but the finding here that ACC particles are formed inside tissue may make coral skeleton formation less susceptible to ocean acidification than previously assumed. If this is how other corals form their skeletons, perhaps this is how a few corals survived past CO2 increases, such as the Paleocene-Eocene Thermal Maximum that occurred 56 Mya.


Subject(s)
Anthozoa/metabolism , Calcium Carbonate/chemistry , Calcium Carbonate/metabolism , Animals , Anthozoa/growth & development , Anthozoa/physiology , Calcification, Physiologic/physiology , Coral Reefs , Crystallization , Ecosystem , Hydrogen-Ion Concentration , Minerals , Seawater/chemistry
4.
ACS Nano ; 11(7): 6612-6622, 2017 07 25.
Article in English | MEDLINE | ID: mdl-28564539

ABSTRACT

Coral skeletons were long assumed to have a spherulitic structure, that is, a radial distribution of acicular aragonite (CaCO3) crystals with their c-axes radiating from series of points, termed centers of calcification (CoCs). This assumption was based on morphology alone, not on crystallography. Here we measure the orientation of crystals and nanocrystals and confirm that corals grow their skeletons in bundles of aragonite crystals, with their c-axes and long axes oriented radially and at an angle from the CoCs, thus precisely as expected for feather-like or "plumose" spherulites. Furthermore, we find that in both synthetic and coral aragonite spherulites at the nanoscale adjacent crystals have similar but not identical orientations, thus demonstrating by direct observation that even at nanoscale the mechanism of spherulite formation is non-crystallographic branching (NCB), as predicted by theory. Finally, synthetic aragonite spherulites and coral skeletons have similar angle spreads, and angular distances of adjacent crystals, further confirming that coral skeletons are spherulites. This is important because aragonite grows anisotropically, 10 times faster along the c-axis than along the a-axis direction, and spherulites fill space with crystals growing almost exclusively along the c-axis, thus they can fill space faster than any other aragonite growth geometry, and create isotropic materials from anisotropic crystals. Greater space filling rate and isotropic mechanical behavior are key to the skeleton's supporting function and therefore to its evolutionary success. In this sense, spherulitic growth is Nature's 3D printing.

5.
Phys Rev Lett ; 110(6): 063902, 2013 Feb 08.
Article in English | MEDLINE | ID: mdl-23432243

ABSTRACT

Exploiting the time-reversal invariance and reciprocal properties of the lossless wave equation enables elegantly simple solutions to complex wave-scattering problems and is embodied in the time-reversal mirror. Here we demonstrate the implementation of an electromagnetic time-reversal mirror in a wave chaotic system containing a discrete nonlinearity. We demonstrate that the time-reversed nonlinear excitations reconstruct exclusively upon the source of the nonlinearity. As an example of its utility, we demonstrate a new form of secure communication and point out other applications.

6.
Article in English | MEDLINE | ID: mdl-24483534

ABSTRACT

We consider time reversal of electromagnetic waves in a closed, wave-chaotic system containing a discrete, passive, harmonic-generating nonlinearity. An experimental system is constructed as a time-reversal mirror, in which excitations generated by the nonlinearity are gathered, time-reversed, transmitted, and directed exclusively to the location of the nonlinearity. Here we show that such nonlinear objects can be purely passive (as opposed to the active nonlinearities used in previous work), and we develop a higher data rate exclusive communication system based on nonlinear time reversal. A model of the experimental system is developed, using a star-graph network of transmission lines, with one of the lines terminated by a model diode. The model simulates time reversal of linear and nonlinear signals, demonstrates features seen in the experimental system, and supports our interpretation of the experimental results.

7.
Psychiatry Res ; 152(2-3): 281-5, 2007 Aug 30.
Article in English | MEDLINE | ID: mdl-17449109

ABSTRACT

Previous research has indicated a potential bi-directional link between youth substance use and externalizing psychiatric comorbidities. We hypothesized that the degree of externalizing symptoms predicts the likelihood of successful smoking cessation (prolonged abstinence) among adolescent smokers participating in a cessation trial. We also explored the association of externalizing symptoms with age at smoking initiation. Ninety one adolescents (mean+/-S.D.; age 15.1+/-1.4 years, cigarettes per day 18.4+/-8.1, Fagerström Test for Nicotine Dependence 7.1+/-1.3) were included. The Child Behavior Checklist/4-18 and Youth Self-Report assessed the degree of externalizing symptoms. Regression analysis indicated that lower CBCL externalizing scores significantly predicted the likelihood of prolonged abstinence. Pearson's correlation analysis indicated a significant association of lower externalizing scores with later onset of smoking initiation. Our findings highlight the importance of addressing externalizing behaviors in adolescent smoking cessation programs.


Subject(s)
Smoking Cessation/methods , Smoking/therapy , Adolescent , Child , Female , Humans , Male , Prevalence , Smoking/epidemiology , Treatment Outcome
8.
Am J Addict ; 16(1): 62-6, 2007.
Article in English | MEDLINE | ID: mdl-17364424

ABSTRACT

This study explored the relationship of a diagnosis of conduct disorder (CD) with the developmental smoking trajectory among 117 adolescent volunteers. Logistic regression analyses revealed that adolescents with CD smoked their first whole cigarette earlier (p = 0.03) and sought cessation treatment earlier (p = .01) compared to non-CD adolescents. Additionally, adolescents who smoked their first whole cigarette before the age of nine were eight times more likely to have CD. These findings suggest that in addition to addressing disruptive behaviors, early prevention and access to interventions for tobacco use are needed for youths with CD.


Subject(s)
Cognitive Behavioral Therapy/methods , Conduct Disorder/epidemiology , Patient Acceptance of Health Care/statistics & numerical data , Smoking Cessation/methods , Smoking Prevention , Smoking/epidemiology , Adolescent , Conduct Disorder/diagnosis , Conduct Disorder/psychology , Diagnostic and Statistical Manual of Mental Disorders , Double-Blind Method , Female , Humans , Male
9.
Free Radic Biol Med ; 39(2): 145-51, 2005 Jul 15.
Article in English | MEDLINE | ID: mdl-15964506

ABSTRACT

Nitric oxide (NO) plays a major role in human physiology and in many pathological states. Although oxyhemoglobin is known to destroy NO activity, NO activity can, in principle, be conserved through iron nitrosylation at vacant hemes. In order for this NO activity to be delivered, the NO must dissociate from the heme. Despite its study over the past few decades, our understanding of NO dissociation from hemoglobin is incomplete. In principle, there are at least four NO dissociation rates: kR(alpha), kR(beta), kT(alpha), and kT(beta), where the subscript refers to the quaternary state and the superscript to the hemoglobin chain. In the T-state, a proportion of the proximal histidine bonds break forming pentacoordinate alpha-nitrosyl hemoglobin. In vivo, alpha-nitrosyl hemoglobin predominates over beta-nitrosyl hemoglobin. In this study we have used a fast NO trap, Fe(II)-proline-dithiocarbamate, to measure NO dissociation rates from hemoglobin. We have varied solution conditions so the rate of dissociation from pentacoordinate alpha-nitrosyl hemoglobin could be definitively measured for the first time; kT(alpha) = 4.2 +/- 1.5 x 10(-4) s(-1). We have also found that the fastest NO dissociation rate is on the order of 10(-3) s(-1) and that NO dissociation from sickle cell hemoglobin is the same as that from normal adult hemoglobin.


Subject(s)
Hemoglobins/chemistry , Nitric Oxide/metabolism , Electron Spin Resonance Spectroscopy , Erythrocytes/metabolism , Histidine/chemistry , Humans , Kinetics , Magnetics , Nitrogen/chemistry , Oxyhemoglobins/chemistry , Spectrophotometry , Time Factors
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