ArticleChronic obstructive pulmonary diseases (Miami, Fla.)2020
Hypercapnia in Advanced Chronic Obstructive Pulmonary Disease: A Secondary Analysis of the National Emphysema Treatment Trial.
Article in Chronic obstructive pulmonary diseases (Miami, Fla.), 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers, 1 of them a synthesis that pooled it.
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Who cites it
17 citing papers in PubMed, 1 synthesis or guideline pooled it, 31 citations in OpenAlex.
- A meta-analysis of the effects of long-term oxygen therapy combined with exercise rehabilitation on exercise capacity, cardiopulmonary function, and quality of life in patients with COPD.Frontiers in medicine · 2025Pooled it
- Intraoperative mechanical ventilation management in COPD: A state of the art review.Clinics (Sao Paulo, Brazil) · 2026Review
- Interpreting peripheral oxygen saturation variability in critical illness: A directional framework adjusted for hypoxia severity.Experimental physiology · 2026Article
- Hypercapnia Effects on Lung Function.Comprehensive Physiology · 2026Review
- Prehospital oxygen-therapy and mortality in patients treated by emergency medical services: a prospective, observational multicenter study.World journal of emergency medicine · 2025Article
- Accuracy of early warning scores for predicting clinical worsening in COPD patients.ERJ open research · 2025Article
- Differences in Anthropometric, Sleep and Respiratory Characteristics between Hypercapnic and Normocapnic Patients with COPD-OSA Overlap Syndrome.Journal of personalized medicine · 2024Article
- The Role of Obstructive Sleep Apnea in Hypercapnic Respiratory Failure Identified in Critical Care, Inpatient, and Outpatient Settings.Sleep medicine clinics · 2024Review
- The rate of hypercapnic respiratory failure in a pulmonary function test laboratory database.ERJ open research · 2024Article
- Chronic obstructive pulmonary disease (COPD) and COPD-like phenotypes.Frontiers in medicine · 2024Review
- Observational
- The Management of Acute Exacerbations in COPD: A Retrospective Observational Study and Clinical Audit.Journal of clinical medicine · 2023Article
- Revolutionizing Chronic Obstructive Pulmonary Disease Care with the Open AI Application: ChatGPT.Annals of biomedical engineering · 2023Article
- Home Noninvasive Ventilation for COPD.Respiratory care · 2023Article
- A framework of transient hypercapnia to achieve an increased cerebral blood flow induced by nasal breathing during aerobic exercise.Cerebral circulation - cognition and behavior · 2023Review
- Hypercapnia in COPD: Causes, Consequences, and Therapy.Journal of clinical medicine · 2022Review
- Possibility of Venous Serum ClInternational journal of molecular sciences · 2021Article
Corrections and comments
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Authors and funding
7 authors at 5 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
rationaleHypercapnia develops in one third of patients with advanced chronic obstructive pulmonary disease (COPD) and is associated with increased morbidity and mortality. Multiple factors in COPD are thought to contribute to the development of hypercapnia including increased carbon dioxide (CO
methodsThis is a secondary analysis of the clinical, physiologic and imaging data from the National Emphysema Treatment Trial (NETT). All patients with complete baseline data for the key predictor variables were included. An inclusive list of 32 potential predictor variables were selected
resultsA total of 1419 patients with severe COPD were included in the analysis; mean age 66.4 years (standard deviation 6.3), 38% females, and 422 (29.7%) had baseline hypercapnia. Key variables associated with hypercapnia were low resting partial pressure of oxygen in blood, low minute ventilation (Ve), high volume of exhaled carbon dioxide, low forced expiratory volume in 1 second, high residual volume, lower % emphysema on chest computed tomography, use of oxygen, low ventilatory reserve (high Ve/maximal voluntary ventilation), and not being at high altitude. Low diffusing capacity for carbon monoxide showed a positive association with hypercapnia in univariate analysis but a negative correlation in multivariate analysis. Measures of dyspnea and quality of life did not associate with degree of hypercapnia in multivariable analysis.
conclusionHypercapnia in a well-characterized cohort with severe COPD and emphysema is chiefly related to poor lung mechanics, high CO
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