Skip to main content

Respiratory muscle weakness in acute heart failure patients

Background

Respiratory muscle weakness has been arbitrarily defined as a maximum inspiratory pressure lower than 70% of the predictive value. Patients with chronic heart failure have 30 to 50% prevalence of respiratory muscle weakness, and so far there is no evidence of this prevalence in patients hospitalized with acute heart failure.

Objective

To evaluate maximum inspiratory pressure and the prevalence of respiratory muscle weakness in hospitalized patients with acute heart failure.

Methods

A cohort study, performed at Hospital Israelita Albert Einstein in acute heart failure patients admitted to our hospital. We excluded patients with chronic pulmonary disease, neurological and neuromuscular disorders, postoperative period and those that needed an orotracheal tube. Patients after respiratory and hemodynamic stability were submitted to a maximum inspiratory pressure (MIP) measurement by a manuvacuometer. Measurement was performed using a facial mask and unidirectional valve with the patient positioned at 45°. We also collected demographic data, brain natriuretic peptide hormone (BNP), ejection fraction estimated by echocardiogram and use of non-invasive ventilation. MIP was measured at two moments, the first measurement as soon as patients were clinically stable and the second measurement before hospital discharge.

Results

We evaluated 50 patients, with a mean age of 75 years (95% CI = 72 to 78.8), mostly male patients (78%, 39 patients), mean ejection fraction of 0.33 (95% CI = 0.31 to 0.35), and 93.5% had ejection fraction lower than 0.45. At hospital admission, 24 patients used NIV (55.8%), and the BNP median value was 726.5 pg/ml (range of 217 to 2,283 pg/ml). The first MIP measurement showed a median of -52 cmH2O (range of -20 to -120 cmH2O), with 35 patients (70%) presenting MIP lower than 70% of the predictive value. Time to the first measurement had a median of 3.5 days (range of 1 to 22 days). At hospital discharge, the median MIP was -53 cmH2O (range of -20 to -150 cmH2O), and maintained 70% of patients with MIP lower than 70% of the predictive value. There was no significant difference between initial and hospital discharge MIP (P = 0.806). Median hospital length of stay was 11 days (range of 4 to 36 days).

Conclusion

Hospitalized patients with acute heart failure have a high prevalence of respiratory muscle weakness, and maintain weakness even after clinical stabilization.

Author information

Affiliations

Authors

Corresponding author

Correspondence to LHR Gonçalves.

Rights and permissions

This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and Permissions

About this article

Cite this article

Gonçalves, L., Veríssimo, P., Timenetsky, K. et al. Respiratory muscle weakness in acute heart failure patients. Crit Care 15, P24 (2011). https://doi.org/10.1186/cc10172

Download citation

Keywords

  • Ejection Fraction
  • Chronic Heart Failure
  • Hospital Discharge
  • Brain Natriuretic Peptide
  • Acute Heart Failure