Lung volume reduction surgery for the treatment of severe emphysema: a study in a single Canadian institution.
Bibliographic record
Abstract
OBJECTIVE: To evaluate lung volume reduction surgery (LVRS) and its effectiveness in improving pulmonary function, exercise capacity and quality of life in a population of emphysema patients referred to and screened in a single centre. DESIGN: A prospective case series. SETTING: A Canadian tertiary care hospital. PATIENTS: Patients with severe emphysema, significant dyspnea and impaired exercise capacity interfering with quality of life. INTERVENTIONS: Bilateral LVRS was performed through a median sternotomy. MAIN OUTCOME MEASURES: Pulmonary function tests (preoperative forced expiratory volume in the first second [FEV1], residual volume [RV]), 6-minute walk (6 MW) distance, quality of life (Medical Outcomes Study 36-item short-form health survey) and degree of dyspnea (Medical Research Council of Great Britain dyspnea scale and the baseline and transitional dyspnea indices) were assessed before LVRS and at 6 and 12 months after. RESULTS: Fifty-seven patients were assessed for LVRS, of whom 10 were selected for surgery. Homogeneous distribution of disease was the most common reason for exclusion. Of the 10 patients operated upon, 1 died of acute cor pulmonale on the fourth postoperative day and 1 died of recurrent exacerbations of chronic obstructive pulmonary disease and chronic respiratory failure at 315 days postoperatively. In the surviving patients, the mean preoperative FEV1 increased from 0.70 L before surgery to 0.90 L at 1 year, with a mean relative increase of 33.4%. The mean RV decreased from 5.57 L to 4.10 L, with a mean relative decrease of 27.6%. The 6 MW distance increased from 302.7 m to 356.9 m at 1 year, with a mean relative increase of 21.6%. Quality of life and degree of dyspnea were improved significantly at 1 year after LVRS. Of the 5 patients on oxygen at home before surgery, 4 were able to reduce their requirements but not to discontinue oxygen. CONCLUSIONS: LVRS is an effective palliative treatment for dyspnea and poor exercise tolerance in highly selected patients. Although the duration of palliation is unknown, our results show that improvements in pulmonary function, exercise, quality of life and degree of dyspnea are preserved over the first year. Only a minority of the patients screened were eligible for surgery. The 2 deaths in our series emphasize the need for even further delineation of selection criteria.
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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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| 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".