Analysis of Variation in Organizational Definitions of Primary Care Panels: A Systematic Review.

Importance: Primary care panel size plays an increasing role in measuring primary care provider (ie, physicians and advanced practice providers, which include nurse practitioners and physician assistants) workload, setting practice capacity, and determining pay and can influence quality of care, access, and burnout. However, reported panel sizes vary widely. Objective: To identify how panels are defined, the degree of variation in these definitions, the consequences of different definitions of panel size, and research on strengths of different approaches. Evidence Review: Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, MEDLINE, Web of Science, Embase, and Dissertations and Theses Global databases were searched from inception to April 28, 2021, for subject headings and text words to capture concepts of primary care panel size. Article review and data abstraction were performed independently by 2 reviewers. Main outcomes reported included rules for adding or removing patients from panels, rules for measuring primary care provider resources, consequences of different rules on reported panel size, and research on advantages and disadvantages of different rules. Findings: The literature search yielded 1687 articles, with 294 potentially relevant articles and 74 containing relevant data. Specific practices were identified from 29 health care systems and 5 empanelment implementation guides. Patients were most commonly empaneled after 1 primary care visit (24 of 34 [70.6%]), but some were empaneled only after several visits (5 [14.8%]), enrollment in a health plan (4 [11.8%]) or any visit to the health care system (1 [3.0%]). Patients were removed when no visit had occurred in a specified look-back period, which varied from 12 to 42 months. Regarding primary care provider resources, half of organizations assigned advanced practice providers independent panels and half had them share panels with a physician, increasing the physician's panel by 50% to 100%. Analyses demonstrated that changes in individual rules for adding patients, removing patients, or estimating primary care provider resources could increase reported panel size from 20% to 100%, without change in actual primary care provider workload. No research was found investigating advantages of different definitions. Conclusions and Relevance: Much variation exists in how panels are defined, and this variation can have substantial consequences on reported panel size. Research is needed on how to define primary care panels to best identify active patients, which could contribute to a widely accepted standard approach to panel definition.

COVID-19 response by New Zealand general surgical departments in tertiary metropolitan hospitals.

BACKGROUND: Worldwide, coronavirus disease 2019 (COVID-19) has significantly challenged the delivery of healthcare. New Zealand (NZ) faced similar potential challenges despite being geographically isolated. Given the rapid change in the COVID-19 pandemic, hospitals in NZ were tasked with formulating their own COVID-19 responses based on the Ministry of Health's (MoH) recommendations. METHODS: This paper evaluates how six metropolitan general surgical departments in NZ had responded to COVID-19 in terms of changes made to rosters, theatres, clinics, acute admissions as well as additional measures taken to reduce the risk of staff exposure. It also explores how NZ fared in comparison with international guidelines and recommendations. Data from each centre were provided by an appointed clinician. RESULTS: All centres had adapted new rosters and a restructuring of teams. Handovers, multidisciplinary team meetings and educational sessions were held virtually. Different strategies were implemented to ration hospital resources and reduce the risk of staff exposure. Non-urgent operations, endoscopies and clinics were deferred with allocation of dedicated COVID-19 operating theatres. Potential COVID-19 suspects were screened prior to admission and treated separately. Various admission and imaging pathways were utilised to increase efficiency. CONCLUSION: General surgical departments in NZ had implemented a comprehensive COVID-19 response but there is room to work towards a more unified national response. Our analysis shows that these centres across NZ had taken a similar approach which was aligned with international practices.

Intraprocedural predictors of post-stent retriever thrombectomy subarachnoid hemorrhage in middle cerebral artery stroke.

BACKGROUND: Stent retriever thrombectomy (SRT) in acute thromboembolic stroke can result in post-thrombectomy subarachnoid hemorrhage (PTSAH). Intraprocedural findings associated with PTSAH are not well defined. OBJECTIVE: To identify angiographic findings and procedural factors during SRT that are associated with PTSAH. MATERIALS AND METHODS: This was a retrospective, observational cohort study of consecutive patients with middle cerebral artery (MCA) acute ischemic stroke treated with SRT. Inclusion criteria were: (1) age ≥18 years; (2) thromboembolic occlusion of the MCA; (3) at least one stent retriever pass beginning in an M2 branch; (4) postprocedural CT or MRI scan within 24 hours; (5) non-enhanced CT Alberta Stroke Program Early CT Score >5. Exclusion criteria included multi-territory stroke before SRT. RESULTS: Eighty-five patients were enrolled; eight patients had PTSAH (group 1) and 77 did not (group 2). Baseline demographic and clinical characteristics were comparable between the two groups. In group 1, a significantly greater proportion of patients had more than two stent retriever passes (62.5% vs 18.2%, P=0.01), a stent retriever positioned ≥2 cm along an M2 branch (100% vs 30.2%, P=0.002), and the presence of severe iatrogenic vasospasm before SRT pass (37.5% vs 5.2%, P=0.02). One patient with PTSAH and associated mass effect deteriorated clinically. CONCLUSIONS: An increased number of stent retriever passes, distal device positioning, and presence of severe vasospasm were associated with PTSAH. Neurological deterioration with PTSAH can occur.

In vitro comparison of linear vs triangular screw configuration to stabilize complete uniarticular parasagittal fractures of the proximal phalanx in horses.

OBJECTIVE: To assess fracture gap reduction and stability of linear vs triangular 4.5-mm lag screw repair of experimental, uniarticular, and complete forelimb proximal phalanx (P1) fractures. STUDY DESIGN: Experimental. SAMPLE POPULATION: Fourteen equine cadaver limbs/horses. METHODS: Simulated fractures were repaired with 2 lag screws under 4-Nm insertion torque (linear repair). Computed tomography (CT) imaging was performed with the leg unloaded and loaded to forces generated while walking. The fracture repair was revised to include 3 lag screws placed with the same insertion torque (triangular repair) prior to CT. The width of the fracture gap was assessed qualitatively by 2 observers and graded on the basis of gap measurements relative to the average voxel size at dorsal, mid, and palmar P1 sites. Interobserver agreement was assessed with Cohen's κ. The effect of repair type, loading condition, and measurement site on fracture gap grades was evaluated by using Kendall's τ-b correlation coefficients and paired nonparametric tests. Significance was set at P ≤ .05. RESULTS: Agreement between loading and fracture gap widening was fair in triangular (κ = 0.53) and excellent in linear (κ = 0.81) repairs. Loading resulted in fracture gap distraction in linear repairs (Plinear = .008). Triangular repairs reduced fractures better irrespective of loading (Punloaded = .003; Ploaded < .001). The type of repair was not correlated with fracture gap grades at unloaded mid and loaded dorsal P1 sites. CONCLUSION: Repair of uniarticular complete parasagittal fractures with a triangular screw configuration improved in vitro fracture gap reduction and stability. CLINICAL SIGNIFICANCE: Triangular lag screw repair likely improves biomechanical conditions during postoperative weight bearing.

From the track to the ocean: Using flow control to improve marine bio-logging tags for cetaceans.

Bio-logging tags are an important tool for the study of cetaceans, but superficial tags inevitably increase hydrodynamic loading. Substantial forces can be generated by tags on fast-swimming animals, potentially affecting behavior and energetics or promoting early tag removal. Streamlined forms have been used to reduce loading, but these designs can accelerate flow over the top of the tag. This non-axisymmetric flow results in large lift forces (normal to the animal) that become the dominant force component at high speeds. In order to reduce lift and minimize total hydrodynamic loading this work presents a new tag design (Model A) that incorporates a hydrodynamic body, a channel to reduce fluid speed differences above and below the housing and wing to redirect flow to counter lift. Additionally, three derivatives of the Model A design were used to examine the contribution of individual flow control features to overall performance. Hydrodynamic loadings of four models were compared using computational fluid dynamics (CFD). The Model A design eliminated all lift force and generated up to ~30 N of downward force in simulated 6 m/s aligned flow. The simulations were validated using particle image velocimetry (PIV) to experimentally characterize the flow around the tag design. The results of these experiments confirm the trends predicted by the simulations and demonstrate the potential benefit of flow control elements for the reduction of tag induced forces on the animal.

Improving Access to Care at Autism Treatment Centers: A System Analysis Approach.

OBJECTIVE: The prevalence of autism spectrum disorder is steadily increasing and placing more demands on already overburdened diagnostic and treatment systems. A thoughtful, systematic reorganization of autism service delivery may reduce delays and better meet the growing need. METHODS: Two clinical centers in the Autism Intervention Research Network on Physical Health, Cincinnati Children's Hospital Medical Center (CCHMC) and Nationwide Children's Hospital (NCH), undertook a year-long access improvement project to reduce delays to care by using system analysis to identify sources of delay and to target changes by using a set of defined access principles. Although both sites addressed access, they focused on slightly different targets (reducing number of patients with autism spectrum disorders waiting for follow-up appointments at NCH and reducing delay to new diagnosis at CCHMC). RESULTS: Both sites achieved dramatic improvements in their complex, multidisciplinary systems. A 94% reduction in number of patients on the waitlist from 99 to 6 patients and a 22% reduction in median delay for a new ongoing care appointment were realized at NCH. A 94% reduction in third next available appointment for new physician visits for children 3 to 5 years old was realized at CCHMC. CONCLUSIONS: This article demonstrates that 2 different clinical systems improved access to care for autism diagnosis and follow-up care by identifying sources of delay and using targeted changes based on a set of access change principles. With appropriate guidance and data analysis, improvements in access can be made.

The Relationship of Obesity to Increasing Health-Care Burden in the Setting of Orthopaedic Polytrauma.

BACKGROUND: With the rise of obesity in the American population, there has been a proportionate increase of obesity in the trauma population. The purpose of this study was to use a computed tomography-based measurement of adiposity to determine if obesity is associated with an increased burden to the health-care system in patients with orthopaedic polytrauma. METHODS: A prospective comprehensive trauma database at a level-I trauma center was utilized to identify 301 patients with polytrauma who had orthopaedic injuries and intensive care unit admission from 2006 to 2011. Routine thoracoabdominal computed tomographic scans allowed for measurement of the truncal adiposity volume. The truncal three-dimensional reconstruction body mass index was calculated from the computed tomography-based volumes based on a previously validated algorithm. A truncal three-dimensional reconstruction body mass index of <30 kg/m(2) denoted non-obese patients and ≥ 30 kg/m(2) denoted obese patients. The need for orthopaedic surgical procedure, in-hospital mortality, length of stay, hospital charges, and discharge disposition were compared between the two groups. RESULTS: Of the 301 patients, 21.6% were classified as obese (truncal three-dimensional reconstruction body mass index of ≥ 30 kg/m(2)). Higher truncal three-dimensional reconstruction body mass index was associated with longer hospital length of stay (p = 0.02), more days spent in the intensive care unit (p = 0.03), more frequent discharge to a long-term care facility (p < 0.0002), higher rate of orthopaedic surgical intervention (p < 0.01), and increased total hospital charges (p < 0.001). CONCLUSIONS: Computed tomographic scans, routinely obtained at the time of admission, can be utilized to calculate truncal adiposity and to investigate the impact of obesity on patients with polytrauma. Obese patients were found to have higher total hospital charges, longer hospital stays, discharge to a continuing-care facility, and a higher rate of orthopaedic surgical intervention.

The high dose response and functional capability of the DT-702/Pd lithium fluoride thermoluminescent dosimeter.

The United States Navy monitors the dose its radiation workers receive using the DT-702/PD thermoluminescent dosimeter, which consists of the Harshaw 8840 holder and the four-element Harshaw 8841 card. There were two main objectives of this research. In the first objective, the dosimeters were exposed to 100 Gy using electron and x-ray beams and found to respond approximately 30-40% lower than the delivered dose. No significant effect on the under-response was found when dose rate, radiation type, dosimeter position on the phantom, and dosimeter material were varied or when the card was irradiated while enclosed in its holder. Since the current naval policy is to remove from occupational use any thermoluminescent dosimeter with an accumulated deep dose equivalent of 0.05 Sv or greater, the functionality of the dosimeter was also investigated at deep dose equivalents of 0.05, 0.15, and 0.25 Sv using 60Co and 137Cs sources as the second main objective. All dosimeters were annealed following exposure and then exposed to 5.0 mSv from a 90Sr source. In all cases, the dosimeters responded within 3% of the delivered dose, indicating that the dosimeters remained functional as defined by naval dosimetry requirements. However, the anneal time required to clear the thermoluminescent dosimeter's reading was found to increase approximately as the cube root with the delivered dose.

Allergy consult for eosinophilia in an infant.

Specialists in allergy/immunology are often asked to evaluate patients with eosinophilia, with the general assumption of an underlying allergic or immunologic disease. We present a case of an infant referred for marked eosinophilia. Although atopic disease may be in the differential diagnosis, it is rarely associated with hypereosinophilia, and other conditions need to be investigated. Until the underlying cause is identified, systemic corticosteroid therapy may be initiated, mainly in severe cases.

The tubercles on humpback whales' flippers: application of bio-inspired technology.

The humpback whale (Megaptera novaeangliae) is exceptional among the large baleen whales in its ability to undertake aquabatic maneuvers to catch prey. Humpback whales utilize extremely mobile, wing-like flippers for banking and turning. Large rounded tubercles along the leading edge of the flipper are morphological structures that are unique in nature. The tubercles on the leading edge act as passive-flow control devices that improve performance and maneuverability of the flipper. Experimental analysis of finite wing models has demonstrated that the presence of tubercles produces a delay in the angle of attack until stall, thereby increasing maximum lift and decreasing drag. Possible fluid-dynamic mechanisms for improved performance include delay of stall through generation of a vortex and modification of the boundary layer, and increase in effective span by reduction of both spanwise flow and strength of the tip vortex. The tubercles provide a bio-inspired design that has commercial viability for wing-like structures. Control of passive flow has the advantages of eliminating complex, costly, high-maintenance, and heavy control mechanisms, while improving performance for lifting bodies in air and water. The tubercles on the leading edge can be applied to the design of watercraft, aircraft, ventilation fans, and windmills.

A simplified mass-transfer model for visual pigments in amphibian retinal-cone outer segments.

When radiolabeled precursors and autoradiography are used to investigate turnover of protein components in photoreceptive cone outer segments (COSs), the labeled components--primarily visual pigment molecules (opsins)--are diffusely distributed along the COS. To further assess this COS labeling pattern, we derive a simplified mass-transfer model for quantifying the contributions of advective and diffusive mechanisms to the distribution of opsins within COSs of the frog retina. Two opsin-containing regions of the COS are evaluated: the core axial array of disks and the plasmalemma. Numerical solutions of the mass-transfer model indicate three distinct stages of system evolution. In the first stage, plasmalemma diffusion is dominant. In the second stage, the plasmalemma density reaches a metastable state and transfer between the plasmalemma and disk region occurs, which is followed by an increase in density that is qualitatively similar for both regions. The final stage consists of both regions slowly evolving to the steady-state solution. Our results indicate that autoradiographic and cognate approaches for tracking labeled opsins in the COS cannot be effective methodologies for assessing new disk formation at the base of the COS.

Lift and drag performance of odontocete cetacean flippers.

Cetaceans (whales, dolphins and porpoises) have evolved flippers that aid in effective locomotion through their aquatic environments. Differing evolutionary pressures upon cetaceans, including hunting and feeding requirements, and other factors such as animal mass and size have resulted in flippers that are unique among each species. Cetacean flippers may be viewed as being analogous to modern engineered hydrofoils, which have hydrodynamic properties such as lift coefficient, drag coefficient and associated efficiency. Field observations and the collection of biological samples have resulted in flipper geometry being known for most cetacean species. However, the hydrodynamic properties of cetacean flippers have not been rigorously examined and thus their performance properties are unknown. By conducting water tunnel testing using scale models of cetacean flippers derived via computed tomography (CT) scans, as well as computational fluid dynamic (CFD) simulations, we present a baseline work to describe the hydrodynamic properties of several cetacean flippers. We found that flippers of similar planform shape had similar hydrodynamic performance properties. Furthermore, one group of flippers of planform shape similar to modern swept wings was found to have lift coefficients that increased with angle of attack nonlinearly, which was caused by the onset of vortex-dominated lift. Drag coefficient versus angle of attack curves were found to be less dependent on planform shape. Our work represents a step towards the understanding of the association between performance, ecology, morphology and fluid mechanics based on the three-dimensional geometry of cetacean flippers.

Process improvement and supply and demand: the elements that underlie integration.

Integration relies on a series of key change strategies connected by a fundamental dynamic: system capacity has to match demand or it will ultimately result in expanding delay and system failure. A balance of supply and demand is necessary for successful system performance. If demand and capacity are balanced, then delays are not required.

Hydrodynamic flow control in marine mammals.

The ability to control the flow of water around the body dictates the performance of marine mammals in the aquatic environment. Morphological specializations of marine mammals afford mechanisms for passive flow control. Aside from the design of the body, which minimizes drag, the morphology of the appendages provides hydrodynamic advantages with respect to drag, lift, thrust, and stall. The flukes of cetaceans and sirenians and flippers of pinnipeds possess geometries with flexibility, which enhance thrust production for high efficiency swimming. The pectoral flippers provide hydrodynamic lift for maneuvering. The design of the flippers is constrained by performance associated with stall. Delay of stall can be accomplished passively by modification of the flipper leading edge. Such a design is exhibited by the leading edge tubercles on the flippers of humpback whales (Megaptera novaeangliae). These novel morphological structures induce a spanwise flow field of separated vortices alternating with regions of accelerated flow. The coupled flow regions maintain areas of attached flow and delay stall to high angles of attack. The delay of stall permits enhanced turning performance with respect to both agility and maneuverability. The morphological features of marine mammals for flow control can be utilized in the biomimetic design of engineered structures for increased power production and increased efficiency.

Providing timely access to care: what is the right patient panel size?

BACKGROUND: Delays for appointments are prevalent, resulting in patient dissatisfaction, higher costs, and possible adverse clinical consequences. A "just-in-time" approach to patient scheduling, called advanced access, has been effective in reducing delays in multiple clinical settings. Offering most patients appointments on the same day requires achieving an appropriate balance between supply of and demand for appointments, but no methods have been previously proposed to determine what this balance should be. METHODS: A measure of balance is termed the overflow frequency level--the fraction of days when demand exceeds the average number of appointment slots available. A probability model was developed to estimate this measure for any practice. The model can be used in identifying an appropriate panel size or, conversely, the physician capacity needed to provide timely access. RESULTS: Delays for appointments will be excessive unless the ratio of the average daily demand for appointments to the average daily capacity is less than one. This ratio's appropriate value is dependent on the desired overflow frequency level, which indicates the fraction of days for which physician overtime would be necessary to offer most patients same-day appointments. A table provides suggested panel sizes for a range of practice types, and a spreadsheet file is available on request to help determine panel size or physician capacity in any specific situation. CONCLUSION: The simple probability model can be used to improve the timeliness of care while considering the constraints on physicians' working hours.

Improving access to specialty care.

BACKGROUND: Waits and delays plague health care systems worldwide, and wait times for most specialists exceed those for primary care practices. In office-based practices, the provider office presence is not diluted by competing indispensable activities, and the demand for service is most often for a single type, or stream, of office-based appointment demand. In the more complex specialty practices, however, the demand streams for office visits and other services compete for provider time and dilute the supply of office visits. SEVEN FLOW STRATEGIES, WITH A FOCUS ON THE INITIAL APPOINTMENT: Seven strategies for reduction of delay can be applied, not only at all steps in patient flow and for all demand streams but also at all steps (for example, office visit, diagnostic procedure, surgery, follow-up) and within all specialty care types and ranges of practice. Each specialty care practice will need to discover how to use the basic principles and implement customized solutions within its own unique environment. Although it is ultimately critical to eliminate the delays in all streams of service, the focus is on the application of change strategies at the initial step between primary care and all specialty care practice types. The strategies are (1) balance supply and demand at each step in the chain, (2) work down the backlog, (3) reduce appointment types, (4) independent contingency planning for all variation, (5) reduce the demand for visits, (6) increase the supply, and (7) improve the efficiency of the office work flow. SUMMARY: Specialists support various, distinct demand streams that require demand/supply balance to achieve optimal system performance. If demand/supply balance exists within any stream, waits can be minimized, and the practice can choose time frames within which to balance workload.