Effectiveness of pre-operative anaemia screening and increased Tranexamic acid dose policies on outcomes following unilateral primary, elective total hip or knee replacement: a statistical analysis plan for an interrupted time series and regression discontinuity study.

Perioperative blood transfusion is associated with poorer postoperative outcomes following hip and knee replacement surgery. Evidence for the effectiveness of some measures aimed at reducing blood transfusions in this setting are limited and often rely on weak pre-post study designs. Quasi-experimental study designs such as interrupted time series (ITS) and regression discontinuity design (RDD) address many of the weaknesses of the pre-post study design. In addition, a priori publication of statistical analysis plans for such studies increases their transparency and likely validity, as readers are able to distinguish between pre-planned and exploratory analyses. As such, this article, written prospective of any analysis, provides the statistical analysis plan for an ITS and RDD study based on a data set of 20,772 primary elective hip and knee replacement patients in a single English NHS Trust. The primary aim is to evaluate the impact of a preoperative anaemia optimisation service on perioperative blood transfusion (within 7 days of surgery) using both ITS and RDD methods. A secondary aim is to evaluate the impact of a policy of increased tranexamic acid dose given at the time of surgery, using ITS methods.

Preoperative iron treatment in anaemic patients undergoing elective total hip or knee arthroplasty: a systematic review and meta-analysis.

OBJECTIVES: Preoperative anaemia is associated with increased risks of postoperative complications, blood transfusion and mortality. This meta-analysis aims to review the best available evidence on the clinical effectiveness of preoperative iron in anaemic patients undergoing elective total hip (THR) or total knee replacement (TKR). DESIGN: Electronic databases and handsearching were used to identify randomised and non-randomised studies of interventions (NRSI) reporting perioperative blood transfusion rates for anaemic participants receiving iron before elective THR or TKR. Searches of CENTRAL, MEDLINE, Embase, PubMed and other databases were conducted on 17 April 2019 and updated on 15 July 2020. Two investigators independently reviewed studies for eligibility and evaluated risk of bias using the Cochrane risk of bias tool for randomised controlled trials (RCTs) and a modified Newcastle-Ottawa scale for NRSIs. Data extraction was performed by ABS and checked by AB. Meta-analysis used the Mantel-Haenszel method and random-effects models. RESULTS: 807 records were identified: 12 studies met the inclusion criteria, of which 10 were eligible for meta-analyses (one RCT and nine NRSIs). Five of the NRSIs were of high-quality while there were some concerns of bias in the RCT. Meta-analysis of 10 studies (n=2178 participants) showed a 39% reduction in risk of receiving a perioperative blood transfusion with iron compared with no iron (risk ratio 0.61, 95% CI 0.50 to 0.73, p<0.001, I2=0%). There was a significant reduction in the number of red blood cell units transfused with iron compared with no iron (mean difference -0.37units, 95% CI -0.47 to -0.27, p<0.001, I2=40%); six studies (n=1496). Length of stay was significantly reduced with iron, by an average of 2.08 days (95% CI -2.64 to -1.51, p<0.001, I2=40%); five studies (n=1140). CONCLUSIONS: Preoperative iron in anaemic, elective THR or TKR patients, significantly reduces the number of patients and number of units transfused and length of stay. However, high-quality, randomised trials are lacking. PROSPERO REGISTRATION NUMBER: CRD42019129035.

Scaling up Quality Improvement for Surgical Teams (QIST) - avoiding surgical site infection and anaemia at the time of surgery: protocol for a cluster randomised controlled trial.

BACKGROUND: Measures shown to improve outcomes for patients often fail to be adopted into routine practice in the NHS. The Institute for Health Improvement Breakthrough Series Collaborative (BSC) model is designed to support implementation at scale. This trial aims to assess the effectiveness and cost-effectiveness of quality improvement collaboratives (QICs) based on the BSC method for introducing service improvements at scale in the NHS. METHODS: Forty Trusts will be randomised (1:1) to introduce one of two protocols already shown to improve outcomes in patients undergoing elective total hip and knee replacement surgery. The intervention is improvement collaboratives based on the BSC model, a learning system that brings together a large number of teams to seek improvement focussed on a proven intervention. Collaboratives aim to deliver at scale, maximise local engagement and leadership and are designed to build capacity, enable learning and prepare for sustainability. Collaboratives involve Learning Sessions, Action Periods, and a summative congress. Trusts will be supported to introduce either: decolonisation for Methicillin Sensitive Staphylococcus aureus (MSSA) to reduce post-operative infection (QIST: Infection), or an anaemia optimisation programme to reduce peri-operative blood transfusions (QIST: Anaemia). Trusts will continue with their usual practice for whichever protocol they are not introducing. Anonymised data related to both infection and anaemia outcomes for patients undergoing hip or knee arthroplasty at all sites will mean that the two groups act as controls for each other. The primary outcome for the QIST: Infection collaborative is deep MSSA surgical site infection within 90 days of surgery, and for the QIST: Anaemia collaborative is blood transfusion within 7 days of surgery. Patient-level secondary outcomes include length of hospital stay and readmission, which will also inform the economic costings. Qualitative interviews will evaluate the support provided to teams. DISCUSSION: The scale of this trial brings considerable challenges and potential barriers to delivery. Anticipated challenges relate to recruiting and sustaining up to 40 organisations, each with its own culture and context. This complex project with multiple stakeholders across a large geographical area will be managed by experienced senior-level project leaders with a proven track record in advanced project management. The team should ensure effective project governance and communications. TRIAL REGISTRATION: ISRCTN, ISRCTN11085475. Prospectively registered on 15 February 2018.

A decision tool for whole-body CT in major trauma that safely reduces unnecessary scanning and associated radiation risks: An initial exploratory analysis.

BACKGROUND: Whole-body CT (WBCT) has become routine practice in the assessment of major trauma patients. Whilst this may be associated with increased survival, several studies report high rates of negative scans. As no national guideline exists, selection criteria for WBCT vary widely. This study aims to (1) produce a scoring system that improves patient selection for WBCT (2) quantify patient radiation doses and their concomitant risk of malignancy. METHODS: Clinical notes were reviewed for all patients undergoing a WBCT for trauma over a 21-month period at a UK major trauma centre. Clinical and radiological findings were categorised according to body region. Univariate analysis was performed using Chi-squared testing, followed by multivariable logistic regression. Secondary regression analysis of patients with significant injuries that the model did not identify was performed. The model was optimised and used to develop a scoring system. Sensitivity and specificity were calculated using the same dataset as was used to derive the models. Radiation exposure was determined and the excess lifetime risk of malignancy calculated. RESULTS: 255 patients were included, with a mean age of 45 years. 16% of scans were positive for polytrauma, 42% demonstrated some injury and 42% showed no injury. The regression model identified independent predictors of polytrauma to be (1) clinical signs in more than one body region, (2) reduced Glasgow Coma Score, (3) haemodynamic abnormality, (4) respiratory abnormality, (5) mechanism of injury. The final model had a sensitivity of 95% (95% CI 86-99%) and specificity of 59% (95% CI 52-66%) for significant CT findings. Mean radiation exposure was 31.8 mSv, conferring a median excess malignancy risk of 1 in 474. CONCLUSION: After including neurological deficit, our scoring system had a sensitivity of 97% (95% CI 88-99%) and specificity of 56% (95% CI 49-64%) for significant injury. We propose this is used to stratify the use of trauma radiographs, focused CT and WBCT for major trauma patients. Although not intended to replace clinical judgement, our scoring system adds an objective component to decision-making. We believe this will safely reduce the number of unnecessary CT scans performed on a relatively young cohort of patients.