Profile of Alveolar Gases during Periodic and Regular Breathing in Preterm Infants
Bibliographic record
Abstract
To determine the changes in alveolar PCO<sub>2</sub> (P<sub>A</sub>CO<sub>2</sub>) and PO<sub>2</sub> (P<sub>A</sub>O<sub>2</sub>) during periodic and regular breathing epochs in the same infants, we studied 11 preterm infants during quiet sleep (birth weight 1,630 ± 94 g; gestational age 31 ± 1 weeks; postnatal age 32 ± 3 days). A total of 94 breathing/apneic cycles were analyzed and compared with regular periods. During periodic and regular breathing epochs, there were negative correlations of P<sub>A</sub>O<sub>2</sub> on P<sub>A</sub>CO<sub>2</sub>. Short (5 s) and long ( > 5 s) apneas for individual infants occurred along the regression line for that infant. There was not a single overall critical P<sub>A</sub>CO<sub>2</sub> below which apnea occurred, but for individual infants the P<sub>A</sub>CO<sub>2</sub> and the P<sub>A</sub>CO<sub>2</sub> of the breath preceding apnea varied within a limited range. Apneas occurred in clusters of P<sub>A</sub>CO<sub>2</sub> and P<sub>A</sub>O<sub>2</sub> along the average regression line of P<sub>A</sub>O<sub>2</sub> on P<sub>A</sub>CO<sub>2</sub>. Analysis of the data showed that apnea occurred at the lowest P<sub>A</sub>CO<sub>2</sub> and highest P<sub>A</sub>O<sub>2</sub> levels if allowance was made for circulation time. During apnea, ‘the best fit’ for the increase in P<sub>A</sub>CO<sub>2</sub> and the decrease in P<sub>A</sub>O<sub>2</sub> was linear, rather than logarithmic. The findings suggest the following. (1) There is not a single overall critical level of P<sub>A</sub>CO<sub>2</sub> for apnea to occur, but in a given infant this level varies within a limited range. This indicates that these infants are likely breathing near the apnea threshold. (2) Short and long apneas appear to occur randomly along the regression of P<sub>A</sub>O<sub>2</sub> on P<sub>A</sub>CO<sub>2</sub> for a particular infant. (3) The changes in alveolar gases are linear during apnea. The data are consistent with the idea that each infant has an optimum narrow range of P<sub>A</sub>CO<sub>2</sub> and P<sub>A</sub>O<sub>2</sub> values in which apnea occurs.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".