Predicting Factors for Requiring Routine Postoperative Blood Analysis in Primary Hip and Knee Arthroplasty: A Prospective Study.

Background Minimising unnecessary expenditure is essential to cope with high demands on the health sector. A set of full blood count, electrolyte, creatinine and urea tests cost £12 in the National Health Service (NHS). Identifying selected patients requiring postoperative blood tests following primary knee and hip arthroplasty will avoid unnecessary tests and help to reduce expenditure.  The aim of our study is to propose criteria for requesting postoperative blood tests that are safe and do not miss patients. Materials and methods We prospectively evaluated 126 patients (72 in the total knee replacement (TKR) group and 54 in the total hip replacement (THR) group) who underwent either an elective primary THR or a TKR. The mean patient age was 71 years. Patient demographics as well as in-patient events throughout each patient's hospital stay were recorded. Hospital readmissions were also monitored for up to 90 days postoperatively.  Statistical analysis was performed using SPSS Statistics software (IBM Corp., Armonk, NY) with paired t-tests / Wilcox and mixed measures analysis of variance. Binary logistic regression was used to identify predictors of patients requiring a postoperative blood test. Results Analysis of our data identified the following as risk factors for requiring postoperative full blood count tests, including pre-operative Hb of ≤ 110 g/L, cardiac disease, clinical features of anaemia postoperatively and intraoperative blood loss of > 500 mL. The additional risk factors identified for requiring postoperative electrolyte and urea tests are deranged pre-operative electrolytes and clinical signs or symptoms of electrolyte/renal disturbance such as anuria. No patient was readmitted within 90 days of discharge. Conclusion Overall, applying the criteria we have devised would have saved 74 blood tests in the cohort of 126 patients. This provides an odds ratio of 14.0 (95% confidence interval: 1.77-110, p=0.012) of an abnormal result in the patients that would have been tested, compared to those that would not have been tested.

Associations between physical activity levels and renal recovery following acute kidney injury stage 3: a feasibility study.

BACKGROUND: Acute kidney injury (AKI) can lead to chronic kidney disease, which results in poor long-term outcomes. There is plausibility that increased levels of physical activity may promote renal recovery post-AKI. This study aimed to investigate associations between physical activity levels and renal recovery following stage 3 AKI, and to assess the feasibility of measuring physical activity levels in this population. METHODS: Forty One hospitalised patients with AKI stage 3 were enrolled. Serum creatinine and estimated glomerular filtration rate (eGFR) were collected at 12 months prior to the development of AKI, during the hospital admission when the episode of AKI stage 3 occurred, and at 1-, 3- and 6-months post discharge. All participants completed the General Practice Activity Questionnaire (GPPAQ) to assess physical activity levels. A pedometer was also worn for 7 days immediately following discharge and at 6-months post discharge to ascertain an average daily step count. Feasibility outcomes including eligibility, recruitment and retention rates, and losses to follow up were also assessed. RESULTS: The average (± SD) baseline eGFR and median (IQR) serum creatinine was 71 ± 20 mL/min/1.73m2 and 85 (49) µmol/L respectively. A threefold increase in creatinine occurred during hospitalisation 436 (265) µmol/L. Greatest renal recovery occurred prior to discharge, with recovery continuing for a further three months. Inactive individuals (low GPPAQ scores) had consistently higher serum creatinine values compared to those who were active: 1 months 122 (111) µmol/L vs 70 (0) µmol/L, 6 months 112 (57) µmol/L vs 68 (0) µmol/L. Individuals with higher step counts also displayed better renal recovery 6-months post discharge (r = -0.600, p = 0.208). CONCLUSIONS: Higher levels of physical activity are associated with improved renal recovery after 6- months following an episode of stage 3 AKI. A future randomised controlled trial is feasible and would be required to confirm these initial findings.

Circulating endotoxin and inflammation: associations with fitness, physical activity and the effect of a 6-month programme of cycling exercise during haemodialysis.

BACKGROUND: Intradialytic cycling (IDC) may provide cardiovascular benefits to individuals receiving haemodialysis, but the exact mechanism behind these improvements remains unclear. The primary aim of this study was to investigate the effect of a 6-month programme of IDC on circulating endotoxin (secondary analysis from the CYCLE-HD trial). Secondary aims were to investigate changes in circulating cytokines [interleukin-6 (IL-6), IL-10, tumour necrosis factor-α, C-reactive protein (CRP) and the IL-6:IL-10 ratio] and their associations with physical activity, fitness and cardiovascular outcomes. METHODS: Participants were randomized to either a 6-month programme of IDC (thrice weekly, moderate intensity cycling at a rating of perceived exertion of 12-14) in addition to usual care (n = 46) or usual care only (control group; n = 46). Outcome measures were obtained at baseline and then again at 6 months. RESULTS: There was no significant (P = 0.137) difference in circulating endotoxin between groups at 6 months (IDC group: 0.34 ± 0.08 EU/mL; control group: 0.37 ± 0.07 EU/mL). There were no significant between-group differences in any circulating cytokine following the 6-month programme of IDC. Higher levels of physical activity and fitness were associated with lower levels of endotoxin, IL-6, CRP and IL-6:IL-10 ratio. CONCLUSIONS: Our data show no change in circulating endotoxin or cytokines following a 6-month programme of IDC. However, higher levels of physical activity outside of haemodialysis were associated with lower levels of inflammation.

A Cost-Effective Analysis of the CYCLE-HD Randomized Controlled Trial.

INTRODUCTION: No formal cost-effectiveness analysis has been performed for programs of cycling exercise during dialysis (intradialytic cycling [IDC]). The objective of this analysis is to determine the effect of a 6-month program of IDC on health care costs. METHODS: This is a retrospective formal cost-effectiveness analysis of adult participants with end-stage kidney disease undertaking in-center maintenance hemodialysis enrolled in the CYCLE-HD trial. Data on hospital utilization, primary care consultations, and prescribed medications were extracted from medical records for the 6 months before, during, and after a 6-month program of thrice-weekly IDC. The cost-effectiveness analysis was conducted from a health care service perspective and included the cost of implementing the IDC intervention. The base-case analyses included a 6-month "within trial" analysis and a 12-month "within and posttrial" analysis considering health care utilization and quality of life (QoL) outcomes. RESULTS: Data from the base-case within trial analysis, based on 109 participants (n = 56 control subjects and n = 53 IDC subjects) showed a reduction in health care utilization costs between groups, favoring the IDC group, and a 73% chance of IDC being cost-effective compared with control subjects at a willingness to pay of £20,000 and £30,000 per quality-adjusted life year (QALY) gained. When QoL data points were extrapolated forward to 12 months, the probability of IDC being cost-effective was 93% and 94% at £20,000 and £30,000 per QALY gained. Sensitivity analysis broadly confirms these findings. CONCLUSION: A 6-month program of IDC is cost-effective and the implementation of these programs nationally should be a priority.

A randomized controlled trial to investigate the effects of intra-dialytic cycling on left ventricular mass.

Cardiovascular disease is the leading cause of death for patients receiving hemodialysis. Since exercise mitigates many risk factors which drive cardiovascular disease for these patients, we assessed effects of a program of intra-dialytic cycling on left ventricular mass and other prognostically relevant measures of cardiovascular disease as evaluated by cardiac MRI (the CYCLE-HD trial). This was a prospective, open-label, single-blinded cluster-randomized controlled trial powered to detect a 15g difference in left ventricular mass measured between patients undergoing a six-month program of intra-dialytic cycling (exercise group) and patients continuing usual care (control group). Pre-specified secondary outcomes included measures of myocardial fibrosis, aortic stiffness, physical functioning, quality of life and ventricular arrhythmias. Outcomes were analyzed as intention-to-treat according to a pre-specified statistical analysis plan. Initially, 130 individuals were recruited and completed baseline assessments (65 each group). Ultimately, 101 patients completed the trial protocol (50 control group and 51 exercise group). The six-month program of intra-dialytic cycling resulted in a significant reduction in left ventricular mass between groups (-11.1g; 95% confidence interval -15.79, -6.43), which remained significant on sensitivity analysis (missing data imputed) (-9.92g; 14.68, -5.16). There were significant reductions in both native T1 mapping and aortic pulse wave velocity between groups favoring the intervention. There was no increase in either ventricular ectopic beats or complex ventricular arrhythmias as a result of exercise with no significant effect on physical function or quality of life. Thus, a six-month program of intradialytic cycling reduces left ventricular mass and is safe, deliverable and well tolerated.

Predictive Value of the Risk Assessment and Prediction Tool (RAPT) Score for Primary Hip and Knee Arthroplasty Patients: A Single-Center Study.

The Risk Assessment and Prediction Tool (RAPT) was developed to predict patient discharge destination for arthroplasty operations. However, since Enhanced Recovery After Surgery (ERAS) programs have been utilized in the UK, the RAPT score has not been validated for use. The aim of the current study was to evaluate the predictive validity of the RAPT score in an ERAS environment with short length of stay. Data were compiled from 545 patients receiving a primary elective total hip or total knee arthroplasty in a district general hospital over 12 months. RAPT scores, length of stay, and discharge destinations were recorded. Patients were classified as low, intermediate, or high risk as per their RAPT score. Length of stay was significantly different between groups (p = 0.008), with low-risk patients having shorter length of stay. However, RAPT scores did not predict discharge destination; the overall correct prediction was only 31.9%. Furthermore, the most likely discharge destination was directly home in ≤3 days in all groups (68.5%, 60.2%, and 40% for the low-, intermediate-, and high-risk groups, respectively). The RAPT score is not an adequate tool to predict the discharge disposition following primary total knee and hip replacement surgery in a UK hospital with a standardized modern ERAS program. Alternative predictive tools are required.

Standardising the measurement of physical activity in people receiving haemodialysis: considerations for research and practice.

BACKGROUND: Physical activity (PA) is exceptionally low amongst the haemodialysis (HD) population, and physical inactivity is a powerful predictor of mortality, making it a prime focus for intervention. Objective measurement of PA using accelerometers is increasing, but standard reporting guidelines essential to effectively evaluate, compare and synthesise the effects of PA interventions are lacking. This study aims to (i) determine the measurement and processing guidance required to ensure representative PA data amongst a diverse HD population, and; (ii) to assess adherence to PA monitor wear amongst HD patients. METHODS: Clinically stable HD patients from the UK and China wore a SenseWear Armband accelerometer for 7 days. Step count between days (HD, Weekday, Weekend) were compared using repeated measures ANCOVA. Intraclass correlation coefficients (ICCs) determined reliability (≥0.80 acceptable). Spearman-Brown prophecy formula, in conjunction with a priori ≥  80% sample size retention, identified the minimum number of days required for representative PA data. RESULTS: Seventy-seven patients (64% men, mean ± SD age 56 ± 14 years, median (interquartile range) time on HD 40 (19-72) months, 40% Chinese, 60% British) participated. Participants took fewer steps on HD days compared with non-HD weekdays and weekend days (3402 [95% CI 2665-4140], 4914 [95% CI 3940-5887], 4633 [95% CI 3558-5707] steps/day, respectively, p < 0.001). PA on HD days were less variable than non-HD days, (ICC 0.723-0.839 versus 0.559-0.611) with ≥ 1 HD day and ≥  3 non-HD days required to provide representative data. Using these criteria, the most stringent wear-time retaining ≥ 80% of the sample was ≥7 h. CONCLUSIONS: At group level, a wear-time of ≥7 h on ≥1HD day and ≥ 3 non-HD days is required to provide reliable PA data whilst retaining an acceptable sample size. PA is low across both HD and non- HD days and future research should focus on interventions designed to increase physical activity in both the intra and interdialytic period.

Implementing a theory-based intradialytic exercise programme in practice: a quality improvement project.

BACKGROUND: Research evidence outlines the benefits of intradialytic exercise (IDE), yet implementation into practice has been slow, ostensibly due to a lack of patient and staff engagement. The aim of this quality improvement project was to improve patient outcomes via the introduction of an IDE programme, evaluate patient uptake and sustainability and enhance the engagement of routine haemodialysis (HD) staff with the delivery of the IDE programme. METHODS: We developed and refined an IDE programme, including interventions designed to increase patient and staff engagement that were based on the Theoretical Domains Framework (TDF), using a series of 'Plan, Do, Study, Act' (PDSA) cycles. The programme was introduced at two UK National Health Service HD units. Process measures included patient uptake, withdrawals, adherence and HD staff involvement. Outcome measures were patient-reported functional capacity, anxiety, depression and symptomology. All measures were collected over 12 months. RESULTS: A total of 95 patients were enrolled in the IDE programme; 64 (75%) were still participating at 3 months, decreasing to 41 (48%) at 12 months. Adherence was high (78%) at 3 months, decreasing to 63% by 12 months. The provision of IDE by HD staff accounted for a mean of 2 (5%) sessions per 3-month time point. Patients displayed significant improvements in functional ability (P = 0.01) and a reduction in depression (P = 0.02) over 12 months, but the effects seen were limited to those who completed the programme. CONCLUSIONS: A theory-based IDE programme is feasible and leads to improvement in functional capacity and depression. Sustaining IDE over time is complicated by high levels of patient withdrawal from the programme. Significant change at an organizational level is required to enhance sustainability by increasing HD staff engagement or access to professional exercise support.

Exercise during hemodialysis does not affect the phenotype or prothrombotic nature of microparticles but alters their proinflammatory function.

Hemodialysis patients have dysfunctional immune systems, chronic inflammation and comorbidity-associated risks of cardiovascular disease (CVD) and infection. Microparticles are biologically active nanovesicles shed from activated endothelial cells, immune cells, and platelets; they are elevated in hemodialysis patients and are associated with chronic inflammation and predictive of CVD mortality in this group. Exercise is advocated in hemodialysis to improve cardiovascular health yet acute exercise induces an increase in circulating microparticles in healthy populations. Therefore, this study aimed to assess acute effect of intradialytic exercise (IDE) on microparticle number and phenotype, and their ability to induce endothelial cell reactive oxygen species (ROS) in vitro. Eleven patients were studied during a routine hemodialysis session and one where they exercised in a randomized cross-over design. Microparticle number increased during hemodialysis (2064-7071 microparticles/µL, P < 0.001) as did phosphatidylserine+ (P < 0.05), platelet-derived (P < 0.01) and percentage procoagulant neutrophil-derived microparticles (P < 0.05), but this was not affected by IDE. However, microparticles collected immediately and 60 min after IDE (but not later) induced greater ROS generation from cultured endothelial cells (P < 0.05), suggesting a transient proinflammatory event. In summary IDE does not further increase prothrombotic microparticle numbers that occurs during hemodialysis. However, given acute proinflammatory responses to exercise stimulate an adaptation toward a circulating anti-inflammatory environment, microparticle-induced transient increases of endothelial cell ROS in vitro with IDE may indicate the potential for a longer-term anti-inflammatory adaptive effect. These findings provide a crucial evidence base for future studies of microparticles responses to IDE in view of the exceptionally high risk of CVD in these patients.

Regular exercise during haemodialysis promotes an anti-inflammatory leucocyte profile.

BACKGROUND: Cardiovascular disease is the most common cause of mortality in haemodialysis (HD) patients and is highly predicted by markers of chronic inflammation. Regular exercise may have beneficial anti-inflammatory effects, but this is unclear in HD patients. This study assessed the effect of regular intradialytic exercise on soluble inflammatory factors and inflammatory leucocyte phenotypes. METHODS: Twenty-two HD patients from a centre where intradialytic cycling was offered thrice weekly and 16 HD patients receiving usual care volunteered. Exercising patients aimed to cycle for 30 min at rating of perceived exertion of 'somewhat hard'. Baseline characteristics were compared with 16 healthy age-matched individuals. Physical function, soluble inflammatory markers and leucocyte phenotypes were assessed again after 6 months of regular exercise. RESULTS: Patients were less active than their healthy counterparts and had significant elevations in measures of inflammation [interleukin-6 (IL-6), C-reactive protein (CRP), tumour necrosis factor-α (TNF-α), intermediate and non-classical monocytes; all P < 0.001]. Six months of regular intradialytic exercise improved physical function (sit-to-stand 60). After 6 months, the proportion of intermediate monocytes in the exercising patients reduced compared with non-exercisers (7.58 ± 1.68% to 6.38 ± 1.81% versus 6.86 ± 1.45% to 7.88 ± 1.66%; P < 0.01). Numbers (but not proportion) of regulatory T cells decreased in the non-exercising patients only (P < 0.05). Training had no significant effect on circulating IL-6, CRP or TNF-α concentrations. CONCLUSIONS: These findings suggest that regular intradialytic exercise is associated with an anti-inflammatory effect at a circulating cellular level but not in circulating cytokines. This may be protective against the increased risk of cardiovascular disease and mortality that is associated with chronic inflammation and elevated numbers of intermediate monocytes.

The Impact of Exercising During Haemodialysis on Blood Pressure, Markers of Cardiac Injury and Systemic Inflammation--Preliminary Results of a Pilot Study.

BACKGROUND/AIMS: Patients requiring haemodialysis have cardiovascular and immune dysfunction. Little is known about the acute effects of exercise during haemodialysis. Exercise has numerous health benefits but in other populations has a profound impact upon blood pressure, inflammation and immune function; therefore having the potential to exacerbate cardiovascular and immune dysfunction in this vulnerable population. METHODS: Fifteen patients took part in a randomised-crossover study investigating the effect of a 30-min bout of exercise during haemodialysis compared to resting haemodialysis. We assessed blood pressure, plasma markers of cardiac injury and systemic inflammation and neutrophil degranulation. RESULTS: Exercise increased blood pressure immediately post-exercise; however, 1 hour after exercise blood pressure was lower than resting levels (106±22 vs. 117±25 mm Hg). No differences in h-FABP, cTnI, myoglobin or CKMB were observed between trial arms. Exercise did not alter circulating concentrations of IL-6, TNF-α or IL-1ra nor clearly suppress neutrophil function. CONCLUSIONS: This study demonstrates fluctuations in blood pressure during haemodialysis in response to exercise. However, since the fall in blood pressure occurred without evidence of cardiac injury, we regard it as a normal response to exercise superimposed onto the haemodynamic response to haemodialysis. Importantly, exercise did not exacerbate systemic inflammation or immune dysfunction; intradialytic exercise was well tolerated.

Patient and Staff Perceptions of Intradialytic Exercise before and after Implementation: A Qualitative Study.

INTRODUCTION: Despite guidance and evidence for the beneficial effects of intradialytic exercise (IDE), such programmes are rarely adopted within practice and little is known about how they may best be sustained. The Theoretical Domains Framework (TDF) was used to guide the understanding of the barriers and facilitators to initial and ongoing IDE participation and to understand how these are influential at each stage. MATERIALS AND METHODS: Focus groups explored patient (n=24) and staff (n=9) perceptions of IDE prior to the introduction of a programme and, six months later, face to face semi-structured interviews captured exercising patients (n=11) and staffs' (n=8) actual experiences. Data were collected at private and NHS haemodialysis units within the UK. All data were audio-recorded, translated where necessary, transcribed verbatim and subject to framework analysis. RESULTS: IDE initiation can be facilitated by addressing the pre-existing beliefs about IDE through the influence of peers (for patients) and training (for staff). Participation was sustained through the observation of positive outcomes and through social influences such as teamwork and collaboration. Despite this, environment and resource limitations remained the greatest barrier perceived by both groups. CONCLUSIONS: Novel methods of staff training and patient education should enhance engagement. Programmes that clearly highlight the benefits of IDE should be more successful in the longer term. The barrier of staff workload needs to be addressed through specific guidance that includes recommendations on staffing levels, roles, training and skill mix.

Inflammatory factors and exercise in chronic kidney disease.

Patients with chronic kidney disease frequently present with chronic elevations in markers of inflammation, a condition that appears to be exacerbated by disease progression and onset of haemodialysis. Systemic inflammation is interlinked with malnutrition and muscle protein wasting and is implicated in a number of morbidities including cardiovascular disease: the most common cause of mortality in this population. Research in the general population and other chronic disease cohorts suggests that an increase in habitual activity levels over a prolonged period may help redress basal increases in systemic inflammation. Furthermore, those populations with the highest baseline levels of systemic inflammation appear to have the greatest improvements from training. On the whole, the activity levels of the chronic kidney disease population reflect a sedentary lifestyle, indicating the potential for increasing physical activity and observing health benefits. This review explores the current literature investigating exercise and inflammatory factors in the chronic kidney disease population and then attempts to explain the contradictory findings and suggests where future research is required.

The influence of exercise training status on antigen-stimulated IL-10 production in whole blood culture and numbers of circulating regulatory T cells.

Highly trained athletes are associated with high resting antigen-stimulated whole blood culture interleukin (IL)-10 production. The purpose of the present study was to examine the effects of training status on resting circulating T regulatory (Treg) cell counts and antigen-stimulated IL-10 production and the effect of acute bout of exercise on the Treg response. Forty participants volunteered to participate and were assigned to one of the four groups: sedentary (SED), recreationally active (REC), sprint-trained athletes and endurance-trained athletes (END). From the resting blood sample, CD4(+)CD25(+)CD127(low/-) Treg cells and in vitro antigen-stimulated IL-10 production were assessed. Ten REC subjects performed 60 min cycling at 70 % of maximal oxygen uptake and blood samples for Treg analysis were collected post- and 1 h post-exercise. IL-10 production was greater in END compared with the other groups (P < 0.05). END had a higher Treg percentage of total lymphocyte count compared with SED (P < 0.05). A smaller proportion of Treg CD4(+) cells were observed in SED compared with all other groups (P < 0.05). IL-10 production significantly correlated with the proportion of Tregs within the total lymphocyte population (r s = 0.51, P = 0.001). No effect of acute exercise was evident for Treg cell counts in the REC subjects (P > 0.05). Our results demonstrate that high training loads in END are associated with greater resting IL-10 production and Treg cell count and suggest a possible mechanism for depression of immunity commonly reported in athletes engaged in high training loads.