Hemodynamic Assessment of Arterial Perfusion by Using the Ultrasonographic Hand Acceleration Time: Protocol for a Cross-Sectional Prospective Descriptive Study
Bibliographic record
Abstract
BACKGROUND: Several noninvasive methods can be used to assess hand perfusion, but none have been standardized for diagnosing chronic upper limb ischemia. One potentially useful diagnostic tool for this purpose is the ultrasonographic hand acceleration time (HAT), although it still requires characterization and validation. OBJECTIVE: This study aims to describe the technique for assessing hand perfusion through HAT while quantifying it in patients with chronic upper limb ischemia and healthy volunteers. METHODS: This prospective, cross-sectional, and descriptive study evaluates HAT measurements by using vascular duplex ultrasound (DUS), a novel technique for assessing hand arterial perfusion. This study includes adult patients with chronic upper limb ischemia and healthy volunteers without cardiovascular risk factors. HAT was measured in 4 different hand arteries. A standard descriptive analysis was performed, along with comparisons using the Mann-Whitney U test, when applicable. This study received institutional review board approval, and no study-related procedures were performed prior to signing the written informed consent. This research complied with the Declaration of Helsinki, Good Clinical Practice guidelines, and Spanish regulatory requirements. RESULTS: As of June 2023, 30 participants were enrolled in the study, comprising 15 patients and 15 healthy volunteers, resulting in a total of 15 ischemic and 30 nonischemic hands. Data analyses were concluded in late November 2023, and results were sent for publication in February 2024. The manuscript containing the results was accepted in May 2024 and published online in July 2024, becoming available in PubMed in December 2024. The results have already been made available to the scientific community prior to the submission of this protocol. This study protocol was submitted for publication in July 2024 to enhance transparency and to offer comprehensive methodological insight into the HAT technique. No additional analyses beyond those reported in the published study are planned. CONCLUSIONS: This study presents the first systematic evaluation of HAT measurements by using vascular DUS as a novel diagnostic tool for chronic upper limb ischemia. By comparing ischemic and nonischemic hands, this study aims to establish preliminary cutoff values that may aid clinical decision-making. Although prior studies have only reported HAT measurements in case reports, this study provides quantitative data on its feasibility and potential clinical application. Despite its small sample size, which limits subgroup analysis and generalizability, the study serves as a foundation for future research by providing essential data for refining cutoff values and informing sample size calculations for larger studies. Although examiner dependence could introduce systematic bias, the standardized methodology ensures consistency across all measurements. Ultimately, HAT may emerge as a quick, noninvasive diagnostic tool for chronic upper limb ischemia, potentially complementing existing nonstandardized methods such as the digital-brachial index, digital pressures, and plethysmography. TRIAL REGISTRATION: ClinicalTrials.gov NCT05977725; https://clinicaltrials.gov/study/NCT05977725. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/64450.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.017 | 0.010 |
| Meta-epidemiology (narrow) | 0.003 | 0.001 |
| Meta-epidemiology (broad) | 0.003 | 0.001 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.002 | 0.002 |
| Insufficient payload (model declined to judge) | 0.021 | 0.007 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".