Pulmonary gas exchange and ventilatory efficiency during exercise in health and diseases

ABSTRACT

Introduction

Cardiopulmonary exercise testing (CPET) is nowadays used to study the exercise response in healthy subjects and in disease. Ventilatory efficiency is one of the main determinants in exercise tolerance, and its main variables are a useful tool to guide pathophysiologists toward specific diagnostic pathways, providing prognostic information and improving disease management, treatment, and outcomes.

Areas covered

This review will be based on today’s available scientific evidence, describing the main physiological determinants of ventilatory efficiency at rest and during exercise, and focusing also on how CPET variables are modified in specific diseases, leading to the possibility of early diagnosis and management.

Expert opinion

Growing knowledge on CPET interpretation and a wider use of this clinical tool is expected in order to offer more precise diagnostic and prognostic information to patients and clinicians, helping in the management of therapeutic decisions. Future research could be able to identify new and more simple markers of ventilatory efficiency, and to individuate new interventions for the improvement of symptoms, such as exertional dyspnea.

KEYWORDS:

• Gas exchange
• ventilatory efficiency
• cardiopulmonary exercise test
• exercise
• respiratory diseases
• cardiological diseases
• respiratory physiology
• respiratory pathophysiology

Article highlights

• CPET and the evaluation of ventilatory efficiency is a fundamental clinical tool for the diagnosis of exercise intolerance or unexplained dyspnea.

• Understanding the physiological determinants of ventilatory regulation at rest and during exercise is crucial for a correct interpretation of CPET in healthy individuals and in disease.

• A correct identification and characterization of ventilatory inefficiency at CPET can lead to differential diagnostic pathways in identifying early stages of different diseases, such as CHF, pulmonary vascular diseases, COPD or less common diseases.

• Growing knowledge on CPET interpretation and a greater distribution of CPET centers must be achieved in order to offer patients better diagnostic opportunities and more specific and reliable diagnostic and prognostic information. Future research may be able to give clinicians new tools to be integrated in diagnostic pathways or to be used to achieve greater knowledge on responses to therapeutic interventions.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.