Pulse Pressure Analysis to Guide Intraoperative Phlebotomy Prior to Cardiac Surgery
Bibliographic record
Abstract
Background:: The aim of this study was to evaluate the response of the LiDCO-rapid™ during intraoperative phlebotomy in anesthetized children prior to surgery for congenital heart disease. Methods:: After the induction of general anesthesia and endotracheal intubation, baseline vital signs were recorded, along with pulse pressure variability (PPV) and stroke volume variability (SVV) from the LiDCO-rapid™ and cerebral oxygenation (rSO 2 ) using near-infrared spectroscopy (NIRS). Phlebotomy was performed over 5 - 10 min with the volume of blood removed calculated to achieve a hematocrit of 24-28% on cardiopulmonary bypass. The primary outcome was a decline in rSO 2 >=5 between the baseline value and the end of phlebotomy. At that time, the correlation of the starting and ending values of SVV and PPV with the NIRS was determined. Results:: The study cohort included 30 patients (mean age of 21 ± 11 years). Statistically significant changes during the study period were observed in rSO 2 , but not in the LiDCO-rapid™ parameters. In analysis of continuous NIRS data, the change in NIRS did not correlate with either baseline (r = 0.10, P = 0.644) or final (r = 0.02, P = 0.914) SVV. Likewise, the change in NIRS did not correlate with baseline (r = 0.01, P = 0.953) or final (r = 0.00, P = 0.982) PPV. Conclusion:: Baseline values as well as changes in the PVV and SVV from the LiDCO-rapid™ did not predict or correlate with changes in cerebral oxygenation measured by NIRS during intraoperative phlebotomy. Our preliminary data suggest that these parameters (PVV and SVV) are not useful in monitoring patient stability or the need for volume replacement during intraoperative phlebotomy prior to cardiac surgery. Cardiol Res. 2017;8(6):276-279 doi: https://doi.org/10.14740/cr634w
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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 | 0.001 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
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".