RCT on T-REX Twente Regimen Effects on Quality of Life and Mobilisation for Cardiac Surgery Patients After Sternotomy

Each year, more than 1000 open-heart surgeries (OHO) are performed at Thorax Centrum Twente (TCT), with 860 of them involving a total median sternotomy. Some patients present themselves at the cardiac care unit with unexplained complaints after discharge, possibly caused by anxiety and insecurity.

There is no consensus regarding postoperative sternal precautions following a total median sternotomy. Studies in the United States and Canada have indicated that these precautions might be too strict, and alternative, less restrictive precautions through the use of the "Keep your Move in the Tube" (KYMITT) approach have been shown safe and without adverse consequences.

Although no statistically significant differences were observed in all outcomes, patients following the new approach (KYMITT) reported fewer issues with functional mobility.

This is a prospective randomized double blind study, collecting data from patients undergoing a total median sternotomy from November 2023 to November 2025 at TCT and concurrently participating in outpatient cardiac rehabilitation under the guidance of TCT.

Previous research using the MacNew quality of life questionnaire among 677 cardiac rehabilitation patients indicated that the difference in response was normally distributed with a standard deviation of 0.25. The KvL-H is the Dutch (validated) translation of the MacNew QLMI. Assuming an effect size of 0.15 (small effect size) across the 4 measurement moments (T0, T2, T4) between the two groups (group*time interaction), a total of 154 patients were needed, i.e. 77 per group. This was based on a Repeated measures ANOVA with an alpha of 0.05, a power of 0.80 and a nonsphericity correction of 1, calculated with G*Power 3.1.9.7. To account for a 10% dropout, 77 patients per group will be included.

A previous study on intensified walking during cardiac rehabilitation after acute myocardial infarction showed a KvL-H increase of 0.9 at the time of discharge (our study: T3) to intake cardiac rehabilitation (our study: T4) from 5.2 to 6.1 at the time of T5. A KvL-H increase of at least 0.15 points is expected in our T-REX Twente sternal precautions group (intervention group); a minimal clinical difference corresponding to a standarized response mean of 0.2.

For the second primary endpoint, the relative percentage of daytime (between 6:00 and 23:00) non-bedtime up to and including 4 days postoperatively on the ICU and nursing ward is examined. From previous research in a similar population, it was observed that a relative rate of lying in bed of 60% is measured on day 1 after discharge from ICU, with a decrease of 6.5% per day (p < 0.001). Assuming a reduction on day 1 to 50%, the medium f2 effect size of 0.5 with a linear mixed model, two-sided testing, alpha of 0.05, power of 0.80 and two predictors (time and group), results in 14 patients needed per group.

The highest number of patients will be retained, i.e. 77 patients per group.

Inclusion criteria

• Adult patients who are preoperatively included if they are undergoing a total median sternotomy at Thorax Centrum Twente (TCT)
• Patients with their treating cardiologist also working for TCT.

Exclusion criteria

• >72 hours of admission to the Intensive Care Unit (ICU)
• Postoperative delirium (diagnosed with Diagnostic and Statistical Manual of Mental Disorders (DSM) version V
• Patients with dementia (or other significant cognitive disorders)
• Dutch language barriers
• Patients with a cardiologist from a location other than TCT