Here is the design of a clinical trial:

Official Title: Effect of Oxiris® Membrane on Microcirculation Following Cardiac Surgery Under Cardiopulmonary Bypass: a Pilot Prospective Monocentric Study (Oxicard Study).

Included conditions:
- Surgery
- Cardiac Event

Study Armgroups:
- {'label': 'With Oxiris', 'type': 'EXPERIMENTAL', 'interventionNames': ['Device: Oxiris']}
- {'label': 'Without Oxiris', 'type': 'NO_INTERVENTION'}

Interventions:
- {'type': 'DEVICE', 'name': 'Oxiris', 'description': 'Oxiris membrane used on the Prismaflex device (Baxter) dedicated to that type of membrane at blood pump flow of 450 ml min-1', 'armGroupLabels': ['With Oxiris']}

Primary Outcomes:
- {'measure': 'Improvement in microcirculatory flow measured by sublingual microcirculation device (SDF/OPS) at day 1 following cardiac surgery with Oxiris membrane during CPB time.', 'timeFrame': 'Day 1'}

Please estimate the sample size based on the assumption: 
Two-sided test with a type 1 error of 0.05 and a power of 90%. No intermediate analysis is planned. A p value of 0.05 will be considered as significant.
Statistical method and sample size calculation
        According to a recent study, we predict a baseline mean MFI of 2.8 with an SD of 0.5.5
        Admitting that the SD of MFI at D1 is 0.5 in both groups, we calculated a sample size of 70 patients to show a difference in MFI of 0.4 at D1 after surgery in a two-sided test with a type 1 error of 0.05 and a power of 90%. Approximately 450 cardiac surgery procedures with bypass surgery are performed per year at Amiens University Hospital. If we consider that 30% of patients will be eligible, this represents a potential inclusion of 130 patients per year. Taking into account possible non-inclusions due to vacations and operating room closures, a total inclusion time of 7 months is expected for a total of 70 patients. Thirty-five patients in each group (standard and interventional groups).
        Primary endpoint will be compared by a Studentâs test or Wilcoxon-Mann-Whitney test as appropriate. Secondary endpoints will be assessed using an analysis of variance test for repeated measures. MACE and mortality rate will be compared with a Ï2 test. ICU and hospital stay will be compared using a Studentâs test. Cumulative event curves will be estimated with the Kaplan-Meier procedure (censored at 30 days). Variables or parameters between usual and intervention groups will be compared with a Studentâs test, a Wilcoxon-Mann-Whitney test, a Ï2 or a Fisherâs exact test as appropriate. A p value of 0.05 will be considered as significant. No intermediate analysis is planned in the trial.