Abstract 254: Comparison of Cold Crystalloid and Colloid Infusions for Induction of Therapeutic Hypothermia in a Porcine Model of Cardiac Arrest
Bibliographic record
Abstract
Introduction: Cold crystalloids have been used for induction of therapeutic hypothermia after cardiac arrest but so far the effectiveness of cold colloids has not been evaluated. This prospective study investigates the cooling effect of rapid intravenous infusion of cold crystalloid compared to colloid in a porcine model of ventricular fibrillation (VF). Methods: VF was electrically induced in twenty-two anesthetized domestic pigs (33 ± 2 kg). Defibrillation was attempted after 15 min CPR using the AutoPulse (Zoll Medical, USA) and artificial ventilation. After spontaneous circulation was restored, the animals were randomized to receive either 1500 mL of 1°C cold Voluven [6% hydroxyethyl starch 130/0.4 in 0.9% NaCl] within 25 min using a Zoll Power Infuser (group A; n = 9), or 1500 mL of 1°C cold normal saline (group B; n = 9), or no infusion (group C; n = 4). The animals were observed for 90 min following infusion. Cerebral, rectal, intramuscular, pulmonary artery, and subcutaneous fat body temperatures (BT) were continuously recorded using GES 130 temperature probes and GMH 3250 digital thermometers with logger function (Greisinger Electronic, Germany). Data were analyzed with JMP 3.2 software (SAS Institute, USA) and are expressed as a mean ± SD. P < 0.05 was considered statistically significant. Results: 45.6 ± 2.7 mL·kg -1 of cold colloid was infused in group A, and 46.8 ± 3.1 mL·kg -1 of crystalloid in group B. The animals treated with cold fluids achieved a significant decrease of BT in all measurement sites while there was a spontaneous increase in group C. At the time of finishing infusion there was a greater decrease in cerebral and pulmonary artery temperatures in group B compared to group A (-1.7 ± 0.4 vs. -1.1 ± 0.3 °C, P < 0.05, and -2.1 ± 0.3 vs. -1.6 ± 0.2 °C, P < 0.05 respectively). Area under the curve (AUC) analysis of the decrease in intra-cerebral BT revealed a more vigorous cooling effect in group B compared to A (-91 ± 30 vs. -62 ± 32 °C·min, P = 0.06). There was also a higher calculated amount of absorbed heat for crystalloids compared to colloids (33.9 ± 5.7 vs. 26.6 ± 3.4 cal, P < 0.05). Conclusion: Cold crystalloid infusions resulted in a more intense cooling effect than colloid infusions of the same temperature and infusion rate in this porcine model of cardiac arrest.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".