Lowering PCO2 With Noninvasive Ventilation Is Associated With Improved Survival in Chronic Hypercapnic Respiratory Failure.

Abstract

BACKGROUND:

Chronic hypercapnic respiratory failure is associated with high mortality. Although previous work has demonstrated a mortality improvement with high-intensity noninvasive ventilation in COPD, it is unclear whether a PCO2 reduction strategy is associated with improved outcomes in other populations of chronic hypercapnia.

METHODS:

The objective of this study was to investigate the association between PCO2 reduction (by using transcutaneous PCO2 as an estimate for PaCO2 and survival in a broad population of individuals treated with noninvasive ventilation for chronic hypercapnia. We hypothesized that reductions in PCO2 would be associated with improved survival. Therefore, we performed a cohort study of all the subjects evaluated from February 2012 to January 2021 for noninvasive ventilation initiation and/or optimization due to chronic hypercapnia at a home ventilation clinic in an academic center. We used multivariable Cox proportional hazard models with time-varying coefficients and PCO2 as a time-varying covariate to test the association between PCO2 and all-cause mortality and when adjusting for known cofounders.

RESULTS:

The mean ± SD age of 337 subjects was 57 ± 16 years, 37% women, and 85% white. In a univariate analysis, survival probability increased with reductions in PCO2 to < 50 mm Hg after 90 d, and these remained significant after adjusting for age, sex, race, body mass index, diagnosis, Charlson comorbidity index, and baseline PCO2 . In the multivariable analysis, the subjects who had a PaCO2 < 50 mm Hg had a reduced mortality risk of 94% between 90 and 179 d (hazard ratio [HR] 0.06, 95% CI 0.01-0.50), 69% between 180 and 364 d (HR 0.31, 95% CI 0.12-0.79), and 73% for 365-730 d (HR 0.27, 95% CI 0.13-0.56).

CONCLUSIONS:

Reduction in PCO2 from baseline for subjects with chronic hypercapnia treated with noninvasive ventilation was associated with improved survival. Management strategies should target the greatest attainable reductions in PCO2 .

• Authors: Jose Victor Jimenez, Jason Ackrivo, Jesse Y Hsu, Mathew W Wilson, Wassim W Labaki, John Hansen-Flaschen, Robert C Hyzy, Philip J Choi
• Journal: Respiratory care (Respir Care) Vol. 68 Issue 12 Pg. 1613-1622 (Nov 25 2023) ISSN: 1943-3654 [Electronic] United States
• PMID: 37137711 (Publication Type: Journal Article)
• Copyright: Copyright © 2023 by Daedalus Enterprises.

Chemical References

• Carbon Dioxide

Topics

• Humans
• Female
• Adult
• Middle Aged
• Aged
• Male
• Noninvasive Ventilation (adverse effects)
• Hypercapnia (therapy, complications)
• Carbon Dioxide
• Pulmonary Disease, Chronic Obstructive (therapy)
• Cohort Studies
• Prospective Studies
• Respiratory Insufficiency (etiology, therapy, diagnosis)