Gas Transfer and Pulmonary Blood Flow at Rest and during Exercise in Adults 21 Years after Preterm Birth
Bibliographic record
Abstract
RATIONALE: After preterm birth, limited data exist in adulthood regarding alveolar-capillary growth and exercise capacity. Gas transfer at rest through exercise is a noninvasive measure of alveolar-capillary development. OBJECTIVES: To determine exercise capacity and gas transfer at rest and during exercise in ex-preterm adults. METHODS: Ex-preterm subjects (n = 60; median gestation, 31.5 wk) recruited at birth underwent exercise testing at 21 years of age and were contemporaneously compared with 50 healthy control subjects. MEASUREMENTS AND MAIN RESULTS: Subjects exercised on a cycle ergometer, and measurements of heart rate (HR), FRC, effective pulmonary blood flow (Qpeff), stroke volume (SV), DL(CO), Vo(2), arteriovenous oxygen difference (AVO), transit time (TT), respiratory rate (Rf), Vco(2), Ve, Vt, and respiratory quotient (RQ) were made using a respiratory mass spectrometer. In the index study group and control subjects, the median DL(CO) (mmol/min/kPa/m(2)) at rest was 4.33 (95% confidence interval [CI], 4.18-4.62) and 4.75 (95% CI, 4.50-5.10), respectively (P = 0.01), and the median Qpeff (L/min/m(2)) at rest was 3.26 (95% CI, 3.16-3.49) and 3.59 (95% CI, 3.43-3.81), respectively (P = 0.04). Qpeff and DL(CO) values normalized during exercise but were reduced and lower than controls after a recovery period. No significant differences were found in exercise capacity between the groups. CONCLUSIONS: The data suggest a long-term effect of premature delivery on resting cardiac output and gas transfer, not due to abnormal cardiac or pulmonary function and with no evidence of exercise limitation.
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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 | 0.000 | 0.001 |
| 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 | 0.001 | 0.000 |
| 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".