Title: Optimising Cardiac Surgery ouTcOmes in People with diabeteS (OCTOPuS)
Funder: Department of Health and Social Care

Abstract: AIM To assess whether a pre-operative out-patient non-doctor delivered intervention to improve glycaemic control improves cardiac surgical outcomes for people with diabetes (DM) DESIGN Multicentre, two arm, individually randomised single blind, superiority trial with internal pilot trial and parallel psychosocial & qualitative investigation SETTING 10-15 centres delivering open cardiac surgery. POPULATION: People with Type 1 and type 2 Diabetes Mellitus INCLUSION: HbA1c >53 mmol/mol at first attendance at cardiothoracic outpatients EXCLUSION: Inability to engage with the trial intervention, for example due to language. Need for urgent surgery, previous cardiac surgery HEALTH TECHNOLOGIES -A manualised intervention to be delivered by a trained health professional, adapted from a scheme currently in use in Bournemouth to be useful to people undergoing cardiac surgery -Treatment as usual Patients will be randomised in a 1:1 ratio between the arms, stratified by centre. Pregenerated permuted blocks will be used to avoid clinicians being able to predict allocation. PRIMARY OUTCOME (main trial) Time from surgery until the patient is fit for discharge OTHER OUTCOMES (main trial) 30 & 90 day mortality, wound infections, chest infections, renal impairment, HbA1c pre-op and, 90 days post op, cost-effectiveness, procedures cancelled due to glycaemic control, quality of life, patient satisfaction & experience. SAMPLE SIZE Internal Pilot: For an expected change in HbA1c from baseline of 5 mmol/mol in the intervention group a sample size of 50 participants (ie 100 across both groups) would allow a margin of error of 4.16 below the mean for a 95% confidence interval (CI). This CI width would allow us to exclude a difference of zero if the treatment difference of 5 was observed. Definitive Trial: The current time until fit for discharge is 7 days, with a standard deviation of 1.5 days. We aim to demonstrate a reduction in the mean time of 0.5 days. With 5% significance and 90% power this will require 382 participants. After listing for surgery, very few patients are lost to follow-up. We will therefore allow for a 5% loss to follow-up and a further 5% for deaths post randomisation, inflating the final target sample size to 426 participants, including those already recruited in the pilot study. HEALTH ECONOMICS In trial analysis from NHS and patient perspectives, considering intervention costs and hospital resources used. TIMETABLE M 1-9 Develop and refine OCTOPuS intervention M 8-13 Complete documentation for main trial M 14 -19 Ethics and R&D approvals M 20-31 Start centres M 20-47 Recruit Patients M 53 Last patient followup point M 53-58 Close out centres, final analysis and reporting EXPERTISE IN TEAM Expertise in diabetes (RH, MP, HP, PNJ), Cardiothoracic Surgery (TV, SO, KS), diabetes intervention development (RH,HP), clinical trials (AC, RH, AW, Southampton CTU), health economics (JL), qualitative research (KB), PPI (AF)

Lay abstract: Diabetes is particularly common in patients having heart surgery. People with diabetes whose blood sugar levels are too high tend to have a slower recovery after surgery. They are more likely to get infections (both chest infections and in their surgical wounds). They cannot go home as quickly after surgery as those with well controlled diabetes. Their risk of death is higher. A hospital in Bournemouth has developed an outpatient based approach to improve blood sugar levels in the weeks before surgery. They have shown that in patients receiving joint replacements, this approach can reduce the time they have to stay in hospital. In this project we will adapt this approach from Bournemouth so that it can be used for people undergoing heart surgery. We will then test it in two hospitals to find out if patients can leave hospital sooner and have a better surgical experience. We will review the intervention with doctors, nurses, and patients; and change it so it can be used for heart surgery patients. We will then test the approach in up to 15 hospitals in a randomised controlled trial, where half the patients receive the new intervention and half receive usual care. After the first 100 patients in the study have had their surgery we will test to see if the intervention has an effect on their diabetes control, by seeing if their HbA1c, which is a measure of average blood sugar levels, has improved. If it has not changed, we will stop the trial, as it will be unlikely that the intervention works as hoped. If the blood sugar levels have improved, we will then invite a further 326 people with diabetes to take part. We will look to see if patients are ready to leave hospital earlier, and also what is the effect on infections and deaths. We will also discuss with patients their experience of the intervention, to make sure that if patients do recover more quickly they think the effort involved in the intervention is worth it. We will also assess the cost of implementing the intervention into NHS care.

Research activity codes: 6.4 SURGERY;7.1 INDIVIDUAL CARE NEEDS
Health categories: CARDIOVASCULAR;METABOLIC AND ENDOCRINE