Participants

As we were unable to find any publication regarding acupuncture for CVR capacity, we could not calculate the appropriate sample size according to the sample size calculation formula. We determined an appropriate sample size of 60 for a pilot study. Both the treatment and control groups will contain 30 eligible participants. The outcomes of this study will aid in the calculation of the appropriate sample size for further randomized clinical trials.

Patients of either sex are eligible for entry into this study if they meet the following inclusion criteria: (1) age between 30 and 80 years with acute cerebral infarction, with an onset time of less than 7 days, (2) confirmed as meeting the Western medicine diagnostic criteria for cerebral infarction issued by the American Heart Association/American Stroke Association (AHA/ASA) in 2015 [52], (3) confirmed as meeting the traditional Chinese medicine diagnostic criteria developed by the Stroke Diagnosis and Curative Effect Evaluation Standard (Draft) of the State Administration of Traditional Chinese Medicine, Acute Encephalopathy Research Group [53], (4) confirmation of diagnosis by head CT or MRI, (5) confirmed CVR impairment as assessed using the breath-holding-test, (6) NIHSS score within the range of 5–20 points, (7) Glasgow Coma Scale score ≥12 points, and (8) agreement to participate in this trial and signing an signed Informed Consent Form.

Patients are ineligible if they meet the following exclusion criteria: (1) use of antithrombotics such as low molecular heparin for the treatment of another conditions, (2) carotid artery stent in situ, (3) severe heart, lung, or kidney disease, (4) inability to cooperate during ultrasound examination of the brain or quantitative evaluation due to another condition.

Reasons for discontinuation of treatment may include, but are not limited to, the following: (1) participant’s decision to discontinue treatment at any time for any reason, (2) investigator’s determination to discontinue treatment for the patient’s safety and best interests at any time, (3) inability to tolerate the treatment stimulation at any time during the course of the study, (4) occurrence of serious side effects during the treatment course, (5) exacerbation of the disease making it difficult for the participant to continue treatment, (6) inability of the participant to cooperate during assessment for any reason, and (7) concomitant therapy during the trial that may affect the study results.

An intention-to-treat approach will be used, and reasons for which patients have been lost to follow-up must be recorded in detail and analyzed after the trial. If the number of cases lost to follow-up is within 10% of all participants, the data from these cases will not be included in the analysis. If the number of cases lost to follow-up exceeds 10%, data from the cases lost in the treatment group will be regarded as invalid, while data from the cases lost in the control group will be regarded as valid. Thus, the effective percentage of the treatment group will remain higher than that of the control group, allowing us to further analyze the efficacy of the intervention.