[Improving vital organs perfusion by the respiratory pump: physiology and clinical use]

Abstract

Objective: In this article, we review the effects of the respiratory pump to improve vital organ perfusion by the use of an inspiratory threshold device.

Data sources: Medline and MeSH database.

Study selection: All papers with a level of proof of I to III have been used.

Data extraction: The analysis of the papers has focused on the physiological modifications induced by intrathoracic pressure regulation.

Data synthesis: Primary function of breathing is to provide gas exchange. Studies of the mechanisms involved in animals and humans provide the physiological underpinnings for "the other side of breathing": to increase circulation to the heart and brain. We describe studies that focus on the fundamental relationship between the generation of negative intrathoracic pressure during inspiration through a low-level of resistance created by an impedance threshold device and the physiologic effects of a respiratory pump. A decrease in intrathoracic pressure during inspiration through a fixed resistance resulting in an intrathoracic pressure of -7 cmH2O has multiple physiological benefits including: enhanced venous return, cardiac stroke volume and aortic blood pressure; lower intracranial pressure; resetting of the cardiac baroreflex; elevated cerebral blood flow oscillations and increased tissue blood flow/pressure gradient.

Conclusion: The clinical and animal studies support the use of the intrathoracic pump to treat different clinical conditions: hemorrhagic shock, orthostatic hypotension, septic shock, and cardiac arrest.

Keywords: Arrêt cardiaque; Cardiac arrest; Cardiovascular collapse; Choc hémorragique; Collapsus cardiovasculaire; Hemorrhagic shock; Impedance threshold device; Intrathoracic pressure; Pression intrathoracique; Resuscitation; Valve d’impédance inspiratoire.