Implementation of Comprehensive Geriatric Assessment based perioperative medicine services to improve clinical outcomes for older patients undergoing elective and emergency surgery with cost effectiveness. [Short title; Perioperative medicine for Older People undergoing Surgery Scale Up (POPS-SUp)]

RESEARCH QUESTION Can CGA-based perioperative medicine services (POPS services) be implemented throughout the NHS, to improve clinical outcomes for older patients undergoing elective and emergency surgery with cost effectiveness? BACKGROUND Increasing numbers of older people are undergoing elective and emergency surgery. Clinical outcomes and cost effectiveness for this group can be improved through perioperative Comprehensive Geriatric Assessment (CGA) and optimisation. Although this CGA approach has been adopted in some hospitals through POPS services, systematic NHS scale up has been hampered by challenges in embedding a multicomponent intervention (CGA) into a complex surgical pathway, with multiple stakeholders. POPS-SUp addresses this issue using the MRC framework for complex interventions. AIM To evaluate implementation, clinical and cost effectiveness of POPS services for older patients undergoing elective and emergency surgery OBJECTIVES To determine if use of a piloted implementation strategy can result in •successful and sustainable implementation of POPS services across the NHS •improved clinical outcomes for patients undergoing elective and/or emergency surgery •cost effective perioperative care METHODS A hybrid implementation-effectiveness interrupted time series study using mixed-methods to examine the use of a coproduced implementation strategy, to support implementation of POPS services and evaluate clinical and cost effectiveness across the NHS. Two sequential cohorts of nine hospitals will be supported over consecutive twelve-month periods, to implement and evaluate POPS services using a piloted, feasible network model (NHS Elect POPS programme). Coprimary outcomes In keeping with MRC framework for complex interventions, the COPRIMARY OUTCOMES are REACH to assess implementation and LENGTH OF HOSPITAL STAY to assess clinical and cost effectiveness. Secondary IMPLEMENTATION outcomes include fidelity to clinical components of perioperative CGA and fidelity to core components of POPS services. Uptake, validity, acceptability and feasibility of the implementation strategy will be assessed through process evaluation. Secondary EFFECTIVENESS outcomes include 30day readmission, Comprehensive Complication Index, return to preoperative place of residence, days alive and out of hospital 90 days, 90day and 12month mortality, operative or non-operative management, HRQoL, clinician defined ‘medically fit for discharge’, shared decision making, decisional regret. Data analysis Implementation and clinical effectiveness outcomes will be analysed through qualitative process evaluation and quantitative analysis. Economic evaluation will act as a vehicle to integrate implementation and clinical findings, with a ‘cost-consequences’ approach presenting evidence on incremental resource effects/costs of POPS (from economic evaluation) alongside quantitative (clinical-effectiveness analysis) and qualitative measures of outcome (process evaluation). IMPACT/DISSEMINATION/TIMELINE POPS-SUp will end uncertainty about how to implement CGA-based perioperative care for patients undergoing emergency and/or elective general or vascular surgery, potentially save lives, improve quality of life and reduce healthcare costs. To achieve this impact in 39 months, the dissemination strategy has been coproduced with all stakeholders and will be codelivered with patients, healthcare professionals, policy makers, academics and the charitable sector.