Just Say NO: Inhaled Nitric Oxide Effect on Respiratory Parameters Following Traumatic Brain Injury in Humans and a Porcine Model.

INTRODUCTION: The mechanism of post-traumatic brain injury (TBI) hypoxemia involves ventilation/perfusion mismatch and loss of pulmonary hypoxic vasoconstriction. Inhaled nitric oxide (iNO) has been studied as an adjunct treatment to avoid the use of high positive end-expiratory pressure and inspired oxygen in treatment-refractory hypoxia. We hypothesized that iNO treatment following TBI would improve systemic and cerebral oxygenation via improved matching of pulmonary perfusion and ventilation. METHODS: Thirteen human patients with isolated TBI were enrolled and randomized to receive either placebo or iNO with measured outcomes including pulmonary parameters, blood gas data, and intracranial pressure (ICP) /perfusion. To complement this study, a porcine model of TBI (including 10 swine) was utilized with measured outcomes of brain tissue blood flow and oxygenation, ventilator parameters, and blood gas data both after administration and following drug removal and clearance. RESULTS: There were no clinically significant changes in pulmonary parameters in either the human or porcine arm following administration of iNO when compared to either the placebo group (human arm) or the internal control (porcine arm). Analysis of pooled human data demonstrated the preservation of alveolar recruitment in TBI patients. There were no clinically significant changes in human ICP or cerebral perfusion pressure following iNO administration compared to controls. CONCLUSIONS: iNO had no significant effect on clinically relevant pulmonary parameters or ICPs following TBI in both human patients and a porcine model. The pressure-based recruitment of the human lungs following TBI was preserved. Further investigation will be needed to determine the degree of utility of iNO in the setting of hypoxia after polytrauma.

Validation of Preload Assessment Technologies at Altitude in a Porcine Model of Hemorrhage.

INTRODUCTION: Dynamic preload assessment measures including pulse pressure variation (PPV), stroke volume variation (SVV), pleth variability index (PVI), and hypotension prediction index (HPI) have been utilized clinically to guide fluid management decisions in critically ill patients. These values aid in the balance of correcting hypotension while avoiding over-resuscitation leading to respiratory failure and increased mortality. However, these measures have not been previously validated at altitude or in those with temporary abdominal closure (TAC). METHODS: Forty-eight female swine (39 ± 2 kg) were separated into eight groups (n = 6) including all combinations of flight versus ground, hemorrhage versus no hemorrhage, and TAC versus no TAC. Flight animals underwent simulated aeromedical evacuation via an altitude chamber at 8000 ft. Hemorrhagic shock was induced via stepwise hemorrhage removing 10% blood volume in 15-min increments to a total blood loss of 40% or a mean arterial pressure of 35 mmHg. Animals were then stepwise transfused with citrated shed blood with 10% volume every 15 min back to full blood volume. PPV, SVV, PVI, and HPI were monitored every 15 min throughout the simulated aeromedical evacuation or ground control. Blood samples were collected and analyzed for serum levels of serum IL-1ß, IL-6, IL-8, and TNF-α. RESULTS: Hemorrhage groups demonstrated significant increases in PPV, SVV, PVI, and HPI at each step compared to nonhemorrhage groups. Flight increased PPV (P = 0.004) and SVV (P = 0.003) in hemorrhaged animals. TAC at ground level increased PPV (P < 0.0001), SVV (P = 0.0003), and PVI (P < 0.0001). When TAC was present during flight, PPV (P = 0.004), SVV (P = 0.003), and PVI (P < 0.0001) values were decreased suggesting a dependent effect between altitude and TAC. There were no significant differences in serum IL-1ß, IL-6, IL-8, or TNF-α concentration between injury groups. CONCLUSIONS: Based on our study, PPV and SVV are increased during flight and in the presence of TAC. Pleth variability index is slightly increased with TAC at ground level. Hypotension prediction index demonstrated no significant changes regardless of altitude or TAC status, however this measure was less reliable once the resuscitation phase was initiated. Pleth variability index may be the most useful predictor of preload during aeromedical evacuation as it is a noninvasive modality.

Postinjury Treatment to Mitigate the Effects of Aeromedical Evacuation After Traumatic Brain Injury in a Porcine Model.

INTRODUCTION: Early aeromedical evacuation after traumatic brain injury (TBI) has been associated with worse neurologic outcomes in murine studies and military populations. The goal of this study was to determine if commonly utilized medications, including allopurinol, propranolol, or tranexamic acid (TXA), could mitigate the secondary traumatic brain injury experienced during the hypobaric and hypoxic environment of aeromedical evacuation. METHODS: Porcine TBI was induced via controlled cortical injury. Twenty nonsurvival pigs were separated into four groups (n = 5 each): TBI+25 mL normal saline (NS), TBI+4 mg propranolol, TBI+100 mg allopurinol, and TBI+1g TXA. The pigs then underwent simulated AE to an altitude of 8000 ft for 4 h with an SpO2 of 82-85% and were sacrificed 4 h later. Hemodynamics, serum cytokines, and hippocampal p-tau accumulation were assessed. An additional survival cohort was partially completed with TBI/NS (n = 5), TBI/propranolol (n = 2) and TBI/allopurinol groups (n = 2) survived to postinjury day 7. RESULTS: There were no significant differences in hemodynamics, tissue oxygenation, cerebral blood flow, or physiologic markers between treatment groups and saline controls. Transient differences in IL-1b and IL-6 were noted but did not persist. Neurological Severity Score (NSS) was significantly lower in the TBI + allopurinol group on POD one compared to NS and propranolol groups. P-tau accumulation was decreased in the nonsurvival animals treated with allopurinol and TXA compared to the TBI/NS group. CONCLUSIONS: Allopurinol, propranolol, and TXA, following TBI, do not induce adverse changes in systemic or cerebral hemodynamics during or after a simulated postinjury flight. While transient changes were noted in systemic cytokines and p-tau accumulation, further investigation will be needed to determine any persistent neurological effects of injury, flight, and pharmacologic treatment.

Beyond the control of the care home: A meta-ethnography of qualitative studies of Infection Prevention and Control in residential and nursing homes for older people.

OBJECTIVE: This study aimed to develop interpretive insights concerning Infection Prevention and Control (IPC) in care homes for older people. DESIGN: This study had a meta-ethnography design. DATA SOURCES: Six bibliographic databases were searched from inception to May 2020 to identify the relevant literature. REVIEW METHODS: A meta-ethnography was performed. RESULTS: Searches yielded 652 records; 15 were included. Findings were categorized into groups: The difficulties of enacting IPC measures in the care home environment; workload as an impediment to IPC practice; the tension between IPC and quality of life for care home residents; and problems dealing with medical services located outside the facility including diagnostics, general practice and pharmacy. Infection was revealed as something seen to lie 'outside' the control of the care home, whether according to origins or control measures. This could help explain the reported variability in IPC practice. Facilitators to IPC uptake involved repetitive training and professional development, although such opportunities can be constrained by the ways in which services are organized and delivered. CONCLUSIONS: Significant challenges were revealed in implementing IPC in care homes including staffing skills, education, workloads and work routines. These challenges cannot be properly addressed without resolving the tension between the objectives of maintaining resident quality of life while enacting IPC practice. Repetitive staff training and professional development with parallel organisational improvements have prospects to enhance IPC uptake in residential and nursing homes. PATIENT OR PUBLIC CONTRIBUTION: A carer of an older person joined study team meetings and was involved in writing a lay summary of the study findings.

Antimicrobial Coating Prevents Ventilator-Associated Pneumonia in a 72 hour Large Animal Model.

BACKGROUND: The primary goal of this study was to demonstrate that endotracheal tubes coated with antimicrobial lipids plus mucolytic or antimicrobial lipids with antibiotics plus mucolytic would significantly reduce pneumonia in the lungs of pigs after 72 hours of continuous mechanical ventilation compared to uncoated controls. MATERIALS AND METHODS: Eighteen female pigs were mechanically ventilated for up to 72 hours through uncoated endotracheal tubes, endotracheal tubes coated with the antimicrobial lipid, octadecylamine, and the mucolytic, N-acetylcysteine, or tubes coated with octadecylamine, N-acetylcysteine, doxycycline, and levofloxacin (6 pigs per group). No exogenous bacteria were inoculated into the pigs, pneumonia resulted from the pigs' endogenous oral flora. Vital signs were recorded every 15 minutes and arterial blood gas measurements were obtained for the duration of the experiment. Pigs were sacrificed either after completion of 72 hours of mechanical ventilation or just prior to hypoxic arrest. Lungs, trachea, and endotracheal tubes were harvested for analysis to include bacterial counts of lung, trachea, and endotracheal tubes, lung wet and dry weights, and lung tissue for histology. RESULTS: Pigs ventilated with coated endotracheal tubes were less hypoxic, had less bacterial colonization of the lungs, and survived significantly longer than pigs ventilated with uncoated tubes. Octadecylamine-N-acetylcysteine-doxycycline-levofloxacin coated endotracheal tubes had less bacterial colonization than uncoated or octadecylamine-N-acetylcysteine coated tubes. CONCLUSION: Endotracheal tubes coated with antimicrobial lipids plus mucolytic and antimicrobial lipids with antibiotics plus mucolytic reduced bacterial colonization of pig lungs after prolonged mechanical ventilation and may be an effective strategy to reduce ventilator-associated pneumonia.

Early Identification of Acute Lung Injury in a Porcine Model of Hemorrhagic Shock.

BACKGROUND: Acute lung injury (ALI) is a frequent complication after severe trauma. Lung-protective ventilation strategies and damage control resuscitation have been proposed for the prevention of ALI; however, there are no clinical or laboratory parameters to predict who is at risk of developing ALI after trauma. In the present study, we explored pulmonary inflammatory markers as a potential predictor of ALI using a porcine model of hemorrhagic shock. MATERIALS AND METHODS: Female swine were randomized to mechanical ventilation with low tidal volume (VT) (6 mL/kg) or high VT (12 mL/kg). After equilibration, animals underwent pressure-controlled hemorrhage (mean arterial pressure [MAP] 35 ± 5 mmHg) for 1 h, followed by resuscitation with fresh whole blood or Hextend. They were maintained at MAP of 50 ± 5 mmHg for 3 h in the postresuscitation phase. Bronchoalveolar lavage fluids were collected hourly and analyzed for inflammatory markers. Lung samples were taken, and porcine neutrophil antibody staining was used to evaluate the presence of neutrophils. ELISA evaluated serum porcine surfactant protein D levels. Sham animals were used as negative controls. RESULTS: Pigs that underwent hemorrhagic shock had higher heart rates, lower cardiac output, lower MAPs, and worse acidosis compared with sham at the early time points (P < 0.05 each). There were no significant differences in central venous pressure or pulmonary capillary wedge pressure between groups. Pulmonary neutrophil infiltration, as defined by neutrophil antibody staining on lung samples, was greater in the shock groups regardless of resuscitation fluid (P < 0.05 each). Bronchoalveolar lavage fluid neutrophil levels were not different between groups. There were no differences in levels of porcine surfactant protein D between groups at any time points, and the levels did not change over time in each respective group. CONCLUSIONS: Our study demonstrates the reproducibility of a porcine model of hemorrhagic shock that is consistent with physiologic changes in humans in hemorrhagic shock. Pulmonary neutrophil infiltration may serve as an early marker for ALI; however, the practicality of this finding has yet to be determined.

The impact of a combinatorial digital and organisational intervention on the management of long-term conditions in UK primary care: a non-randomised evaluation.

BACKGROUND: Better management of long-term conditions remains a policy priority, with a focus on improving outcomes and reducing use of expensive hospital services. A number of interventions have been tested, but many have failed to show benefit in rigorous comparative research. In 2016, the NHS Test Beds scheme was launched to implement and test interventions combining digital technologies and pathway redesign in routine health care settings, with each intervention comprising multiple innovations to better realise benefit from their 'combinatorial' effect. We present the evaluation of one of the NHS Test Beds, which combined risk stratification algorithms, practice-based quality improvement and health monitoring and coaching to improve management of long-term conditions in a single health economy in the north-west of England. METHODS: The NHS Test Bed was implemented in one clinical commissioning group in the north-west of England (patient population 235,800 served by 36 general practices). Routine administrative data on hospital use (the primary outcome) and a selection of secondary outcomes (data from both hospital and primary care) were collected in the intervention site, and from a comparator area in the same region. We used difference-in-differences analysis to compare outcomes in the NHS Test Bed area and the comparator after initiation of the combinatorial intervention. RESULTS: Tests confirmed the existence of parallel trends in the intervention and comparator sites for hospital outcomes for the period April 2016 to March 2017, and for some of the planned primary care outcomes. Based on 10 months of post-intervention secondary care data and 13 months post-intervention primary care data, we found no significant impact on primary outcomes between the intervention and comparator site, and a significant impact on only one secondary outcome. CONCLUSION: A combinatorial digital and organisational intervention to improve the management of long-term conditions was implemented across a whole health economy, but we found no evidence of a positive impact on health care utilisation outcomes in hospital and primary care.

Understanding the diagnosis of pre-diabetes in patients aged over 85 in English primary care: a qualitative study.

BACKGROUND: The benefit of a "diagnosis" of pre-diabetes in very elderly patients is debated. How clinicians manage pre-diabetic blood results in these patients is unknown. This study aims to understand how clinicians are "diagnosing" older patients with pre-diabetic blood parameters. METHODS: Semi-structured interviews and focus groups with health care staff (24 total participants) were conducted in the north of England. Interviews and focus groups were recorded, transcribed and analysed thematically. A grounded theory approach was taken with the theory of candidacy being used as a sensitising concept through which questions were framed and results interpreted. RESULTS: There is a complex system of competing pressures that influence a clinician in deciding whether, and in what way, to inform a very elderly patient that they have pre-diabetes. The majority of clinicians adjust their management of pre-diabetes to the age and perceived risk/benefit for the patient. Whilst some clinicians choose not to inform certain patients of their blood results, many clinicians maintain, what could be seen as a somewhat paradoxical approach of labeling all older patients with pre-diabetes but downplaying the significance to the patient. The policy, organisational context, workload and professional constraints under which clinicians work, play a significant role in shaping how they deal with pre-diabetic blood results in the very elderly. CONCLUSION: There has been recent acknowledgement of how policy and organisational context frames decision-making, but there is a lack of evidence on how this influences uncertainty and dilemmas in decision-making in practice. These findings add further weight for the argument that treatment burden should be included in clinical guidelines.

Financialising acute kidney injury: from the practices of care to the numbers of improvement.

Although sociological studies of quality and safety have identified competing epistemologies in the attempt to measure and improve care, there are gaps in our understanding of how finance and accounting practices are being used to organise this field. This analysis draws on what others have elsewhere called 'financialisation' in order to explore the quantification of qualitatively complex care practices. We make our argument using ethnographic data of a quality improvement programme for acute kidney injury (AKI) in a publicly funded hospital in England. Our study is thus concerned with tracing the effects of financialisation in the emergence and assembly of AKI as an object of concern within the hospital. We describe three linked mechanisms through which this occurs: (1) representing and intervening in kidney care; (2) making caring practices count and (3) decision-making using kidney numbers. Together these stages transform care practices first into risks and then from risks into costs. We argue that this calculative process reinforces a separation between practice and organisational decision-making made on the basis of numbers. This elevates the status of numbers while diminishing the work of practitioners and managers. We conclude by signalling possible future avenues of research that can take up these processes.

Mapping the territory of renal care: a formative analysis of the cognitive work involved in managing acute kidney injury.

The design and evaluation of healthcare work systems requires an understanding of the cognitive work involved in healthcare tasks. Previous studies suggest that a formative approach would be particularly useful to examine healthcare activities for this purpose. In the present study, methods from cognitive work analysis and cognitive task analysis are combined in a formative examination of managing acute kidney injury, an activity that occurs across primary and secondary healthcare settings. The analyses are informed by interviews with healthcare practitioners and a review of practice guidelines. The findings highlight ways in which the task setting influenced practitioners' activity, and ways in which practitioners approached the activity (for example, how they used data to make decisions). The approach taken provided a rich understanding of the cognitive work involved, as well as generating suggestions for the design of work systems to support the clinical task. Practitioner summary: Healthcare tasks often require decision-making in complex and dynamic circumstances, potentially involving collaboration across different practitioner roles and locations. We demonstrate the use of a formative analysis to understand the cognitive work in managing a clinical syndrome across primary and secondary care settings, and consider the implications for work design.

Is telephone health coaching a useful population health strategy for supporting older people with multimorbidity? An evaluation of reach, effectiveness and cost-effectiveness using a 'trial within a cohort'.

BACKGROUND: Innovative ways of delivering care are needed to improve outcomes for older people with multimorbidity. Health coaching involves 'a regular series of phone calls between patient and health professional to provide support and encouragement to promote healthy behaviours'. This intervention is promising, but evidence is insufficient to support a wider role in multimorbidity care. We evaluated health coaching in older people with multimorbidity. METHODS: We used the innovative 'Trials within Cohorts' design. A cohort was recruited, and a trial was conducted using a 'patient-centred' consent model. A randomly selected group within the cohort were offered the intervention and were analysed as the intervention group whether they accepted the offer or not. The intervention sought to improve the skills of patients with multimorbidity to deal with a range of long-term conditions, through health coaching, social prescribing and low-intensity support for low mood. RESULTS: We recruited 4377 older people, and 1306 met the eligibility criteria (two or more long-term conditions and moderate 'patient activation'). We selected 504 for health coaching, and 41% consented. More than 80% of consenters received the defined 'dose' of 4+ sessions. In an intention-to-treat analysis, those selected for health coaching did not improve on any outcome (patient activation, quality of life, depression or self-care) compared to usual care. We examined health care utilisation using hospital administrative and self-report data. Patients selected for health coaching demonstrated lower levels of emergency care use, but an increase in the use of planned services and higher overall costs, as well as a quality-adjusted life year (QALY) gain. The incremental cost per QALY was £8049, with a 70-79% probability of being cost-effective at conventional levels of willingness to pay. CONCLUSIONS: Health coaching did not lead to significant benefits on the primary measures of patient-reported outcome. This is likely related to relatively low levels of uptake amongst those selected for the intervention. Demonstrating effectiveness in this design is challenging, as it estimates the effect of being selected for treatment, regardless of whether treatment is adopted. We argue that the treatment effect estimated is appropriate for health coaching, a proactive model relevant to many patients in the community, not just those seeking care. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number ( ISRCTN12286422 ).

Safety work and risk management as burdens of treatment in primary care: insights from a focused ethnographic study of patients with multimorbidity.

BACKGROUND: In primary health care, patient safety failures can arise in service access, doctor-patient relationships, communication between care providers, relational and management continuity, or technical procedures. Through the lens of multimorbidty, and using qualitative ethnographic methods, our study aimed to illuminate safety issues in primary care. METHODS: Data were triangulated from electronic health records (EHRs); observation of primary care consultations; annual interviews with patients, (informal) care providers and GPs. A thematic analysis of observation, interview and field note material sought to describe the patient safety issues encountered and any associated factors or processes. A more detailed longitudinal description of 6 cases was used to contextualise safety issues identified in observation, interviews and EHRs. RESULTS: Twenty-six patients were recruited. Events which could lead to harm were found in all areas of a framework based on published literature. "Under" and "over" consultation as a precursor of safety failures emerged through thematic analysis of observation and interview material. Other findings concerned workload (for doctors and patients) and the limitations of short consultation times. There were differences in health data collected directly from the patients versus that found in EHRs. Examples included reference to a stroke history and diagnoses for CKD and hypertension. Case study analysis revealed specific issues which appeared contextual to safety concerns, mostly around the management of polypharmacy and patient medication adherence. Clinical imperatives appear around risk management, but the study findings point to a potential conflict with patient expectations around investigation, diagnosis and treatment. DISCUSSION: Patient safety work involves further burdens on top of existing workload for both clinicians and patients. In this conceptualisation, safety work seemingly forms part of a negative feedback loop with patient safety itself. A line of argument drawn from the triangulation of findings from different sources, points to a tension between the desirability of a minimally disruptive medicine versus safety risks possibly associated with 'under' or 'over' consultation. Multimorbidity acts as a magnifier of tensions in the delivery of health services and quality care in general practice. More attention should be put on system design than patient or professional behaviour.

Threats to patient safety in primary care reported by older people with multimorbidity: baseline findings from a longitudinal qualitative study and implications for intervention.

BACKGROUND: In primary care, older patients with multimorbidity (two or more long-term conditions) are especially likely to experience patient safety incidents. Risks to safety in this setting arise as a result of patient, staff and system factors; particularly where these interact or fail to do so. Recent research and policy highlight the important contribution patients can make to improving safety. Older patients with multimorbidity may have the most to gain from increasing their involvement but before interventions can be developed to support them to improve their patient safety, more needs to be known about how this is threatened and how patients respond to perceived threats. We sought to identify and describe threats to patient safety in primary care among older people with multimorbidity, to provide a better understanding of how these are experienced and to inform the development of interventions to reduce risks to patient safety. METHODS: Twenty-six older people, aged 65 or over, with multimorbidity were recruited to a longitudinal qualitative study. At baseline, data on their health and healthcare were collected through semi-structured interviews. Data were analysed thematically, using a framework developed from a previous synthesis of qualitative studies of patient safety in primary care. RESULTS: Threats to patient safety were organised into six themes, across three domains of health and care. These encompassed all aspects of the patient journey, from access to everyday management. Across the journey, many issues arose due to poor communication, and uncoordinated care created extra burdens for patients and healthcare staff. Patients' sense of safety and trust in their care providers were especially threatened when they felt their needs were ignored, or when they perceived responses from staff as inappropriate or insensitive. CONCLUSIONS: For older patients with multimorbidity, patient safety is intrinsically linked to the challenges people face when managing health conditions, navigating the healthcare system, and negotiating care. We consider the implications of this for the development of interventions to reduce threats to patient safety. Potential patient-centred mechanisms include providing patients with more realistic expectations for primary care, and supporting them to communicate their needs and concerns more effectively.

Evaluation of Intensive Care Unit Ventilators at Altitude.

INTRODUCTION: Devices may forgo US military air worthiness and safety testing in an attempt to expedite the availability of critical assets such as mechanical ventilators with a waiver for one-time use in extenuating circumstances. METHODS: We evaluated two Intensive Care Unit (ICU) level ventilators: Drager Evita XL and Puritan Bennett (PB) 840 in an altitude chamber at sea level and altitudes of 8,000 and 16,000 feet. RESULTS: Altitude affected delivered tidal volumes (VTs) in volume control mode (VCV) and Pressure Regulated Volume Controlled (PRVC) mode at altitude with the Evita XL but the differences were not considered clinically important with the PB 840. Sixty-seven percent of the VTs were outside the ASTM standard of ± 10% of set VT with the Evita XL at altitude. CONCLUSION: The PB 840 did not deliver VTs that were larger than the ASTM standard up to an altitude of 16,000 feet while the majority of the delivered VTs with the Därger XL were greater than the ASTM standard. This could present a patient safety issue. Caregivers must be aware of the capabilities and limitations of ICU ventilators when utilized in a hypobaric environment in order to provide safe care.

Preventing Acute Kidney Injury: a qualitative study exploring 'sick day rules' implementation in primary care.

BACKGROUND: In response to growing demand for urgent care services there is a need to implement more effective strategies in primary care to support patients with complex care needs. Improving primary care management of kidney health through the implementation of 'sick day rules' (i.e. temporary cessation of medicines) to prevent Acute Kidney Injury (AKI) has the potential to address a major patient safety issue and reduce unplanned hospital admissions. The aim of this study is to examine processes that may enable or constrain the implementation of 'sick day rules' for AKI prevention into routine care delivery in primary care. METHODS: Forty semi-structured interviews were conducted with patients with stage 3 chronic kidney disease and purposefully sampled, general practitioners, practice nurses and community pharmacists who either had, or had not, implemented a 'sick day rule'. Normalisation Process Theory was used as a framework for data collection and analysis. RESULTS: Participants tended to express initial enthusiasm for sick day rules to prevent AKI, which fitted with the delivery of comprehensive care. However, interest tended to diminish with consideration of factors influencing their implementation. These included engagement within and across services; consistency of clinical message; and resources available for implementation. Participants identified that supporting patients with multiple conditions, particularly with chronic heart failure, made tailoring initiatives complex. CONCLUSIONS: Implementation of AKI initiatives into routine practice requires appropriate resourcing as well as training support for both patients and clinicians tailored at a local level to support system redesign.

Predictors of patient self-report of chronic kidney disease: baseline analysis of a randomised controlled trial.

BACKGROUND: Improving the quality of care for patients with vascular disease is a priority. Clinical guidance has emphasised the importance of early identification and active management of chronic kidney disease (CKD) in primary care in order to maintain vascular health. However, awareness of stage 3 CKD amongst patients remains limited. We aimed to identify predictors of patient self-report of CKD to inform tailoring of conversations around CKD in primary care for diverse patient populations. METHODS: We conducted a cross-sectional analysis of baseline data from 436 patients with stage 3 CKD from 24 GP practices taking part in a randomised controlled trial (RCT) evaluating a complex self-management intervention, which aimed to support the maintenance of vascular health in patients with stage 3 CKD. Potential predictors of patient self-report of CKD included demographics, stage of CKD, cardiovascular risk, self-reported co-morbidities, health status, self-management ability, and health service utilisation. RESULTS: Around half (52%, n = 227) of patients did not self-report CKD. Self-report rates did not appreciably differ by practice. Multivariate analysis revealed that female patients (p = 0.004), and patients with stage 3b CKD (p < 0.001), and with higher anxiety levels (p < 0.001), were more likely to self-report CKD. CONCLUSIONS: Self-report of kidney problems by patients on CKD registers was variable and patterned by sociodemographic factors. Although it cannot be assumed that failure to self-report indicates a lack of awareness of CKD, our data do suggest the need for greater consistency in discussions around kidney health, with meaningful and relevant clinical dialogue that is aligned with existing clinical encounters to enable shared decision making and minimise anxiety.

Evaluation of a volume targeted NIV device: bench evaluation of the Breathe Technologies non-invasive open ventilation system (NIOV™).

PURPOSE: Early ambulation in the ventilated patient is gaining wider acceptance. We evaluated a new portable (1 lb), gas powered, volume ventilator designed for NIV via a proprietary nasal pillows interface (Breathe Technologies, CA). METHODS: We developed a model to approximate a patient's nose, upper airway and trachea. The model was connected to a test lung (ASL5000, Ingmar Medical, Pittsburgh, PA) via 22 mm ID corrugated tubing. The nasal pillows were adjusted in the nares using a lanyard. The ASL was set to represent a normal patient, a COPD patient, and a patient with interstitial lung disease (ILD). The Breathe ventilator was set at delivered volumes of 100 mL, 150 mL, 200 mL, and 250 mL. Baseline data was also collected without the appliance connected. Delivered volume, inspired oxygen concentration (FIO2), inspiratory flow (V), and peak inspiratory pressure (PIP) were recorded for each breath. Data for 10 breaths were used to calculate the mean at each condition (± SD). RESULTS: The Breathe volume ventilator delivered an augmented simulated patient tidal volume of 362 to 823 mL, augmenting the simulated patient's spontaneous volume by up to 459 mL, depending on ventilator settings and ASL lung conditions. Delivered FIO2 ranged from 0.36 to 0.45 and was also dependent on ventilator settings and ASL lung conditions. CONCLUSIONS: The PIP, delivered tidal volumes, and measured FIO2 support the hypothesis that this system can augment minute ventilation and supply supplemental oxygen in spontaneously breathing patients with a simple, non-invasive interface.

Evaluation of a Rebreathing System for Use with Portable Mechanical Ventilators.

INTRODUCTION: Maximizing the capabilities of available lowflow oxygen is key to providing adequate oxygen to prevent/treat hypoxemia and conserve oxygen. We designed a closed-circuit system that allows rebreathing of gases while scrubbing carbon dioxide (CO2) in conjunction with portable mechanical ventilators in a bench model. METHODS: We evaluated the system using two portable mechanical ventilators currently deployed by the Department of Defense-Zoll 731 and AutoMedx SAVe II-over a range of ventilator settings and lung models, using 1 and 3L/min low-flow oxygen into a reservoir bag. We measured peak inspired oxygen concentration (FiO2), CO2-absorbent life, gas temperature and humidity, and the effect of airway suctioning and ventilator disconnection on FiO2 on ground and at altitude. RESULTS: FiO2 was =0.9 across all ventilator settings and altitudes using both oxygen flows. CO2-absorbent life was >7 hours. Airway humidity range was 87%-97%. Mean airway temperature was 25.4°C (SD 0.5°C). Ten-second suctioning reduced FiO2 22%-48%. Thirtysecond ventilator disconnect reduced FiO2 29%-63% depending on oxygen flow used. CONCLUSION: Use of a rebreathing system with mechanical ventilation has the potential for oxygen conservation but requires diligent monitoring of inspired FiO2 and CO2 to avoid negative consequences.

Informing understanding of coordination of care for patients with heart failure with preserved ejection fraction: a secondary qualitative analysis.

BACKGROUND: Patients with heart failure with preserved ejection fraction (HFpEF) are a complex and underserved group. They are commonly older patients with multiple comorbidities, who rely on multiple healthcare services. Regional variation in services and resourcing has been highlighted as a problem in heart failure care, with few teams bridging the interface between the community and secondary care. These reports conflict with policy goals to improve coordination of care and dissolve boundaries between specialist services and the community. AIM: To explore how care is coordinated for patients with HFpEF, with a focus on the interface between primary care and specialist services in England. METHODS: We applied systems thinking methodology to examine the relationship between work-as-imagined and work-as-done for coordination of care for patients with HFpEF. We analysed clinical guidelines in conjunction with a secondary applied thematic analysis of semistructured interviews with healthcare professionals caring for patients with HFpEF including general practitioners, specialist nurses and cardiologists and patients with HFpEF themselves (n=41). Systems Thinking for Everyday Work principles provided a sensitising theoretical framework to facilitate a deeper understanding of how these data illustrate a complex health system and where opportunities for improvement interventions may lie. RESULTS: Three themes (working with complexity, information transfer and working relationships) were identified to explain variability between work-as-imagined and work-as-done. Participants raised educational needs, challenging work conditions, issues with information transfer systems and organisational structures poorly aligned with patient needs. CONCLUSIONS: There are multiple challenges that affect coordination of care for patients with HFpEF. Findings from this study illuminate the complexity in coordination of care practices and have implications for future interventional work.

Defining, identifying and addressing problematic polypharmacy within multimorbidity in primary care: a scoping review.

INTRODUCTION: Polypharmacy and multimorbidity pose escalating challenges. Despite numerous attempts, interventions have yet to show consistent improvements in health outcomes. A key factor may be varied approaches to targeting patients for intervention. OBJECTIVES: To explore how patients are targeted for intervention by examining the literature with respect to: understanding how polypharmacy is defined; identifying problematic polypharmacy in practice; and addressing problematic polypharmacy through interventions. DESIGN: We performed a scoping review as defined by the Joanna Briggs Institute. SETTING: The focus was on primary care settings. DATA SOURCES: Medline, Embase, Cumulative Index to Nursing and Allied Health Literature and Cochrane along with ClinicalTrials.gov, Science.gov and WorldCat.org were searched from January 2004 to February 2024. ELIGIBILITY CRITERIA: We included all articles that had a focus on problematic polypharmacy in multimorbidity and primary care, incorporating multiple types of evidence, such as reviews, quantitative trials, qualitative studies and policy documents. Articles focussing on a single index disease or not written in English were excluded. EXTRACTION AND ANALYSIS: We performed a narrative synthesis, comparing themes and findings across the collective evidence to draw contextualised insights and conclusions. RESULTS: In total, 157 articles were included. Case-finding methods often rely on basic medication counts (often five or more) without considering medical history or whether individual medications are clinically appropriate. Other approaches highlight specific drug indicators and interactions as potentially inappropriate prescribing, failing to capture a proportion of patients not fitting criteria. Different potentially inappropriate prescribing criteria also show significant inconsistencies in determining the appropriateness of medications, often neglecting to consider multimorbidity and underprescribing. This may hinder the identification of the precise population requiring intervention. CONCLUSIONS: Improved strategies are needed to target patients with polypharmacy, which should consider patient perspectives, individual factors and clinical appropriateness. The development of a cross-cutting measure of problematic polypharmacy that consistently incorporates adjustment for multimorbidity may be a valuable next step to address frequent confounding.