Non-invasive estimation of hemodynamic parameters during mechanical ventilation
AssigneeMaquet Critical Care AB
InventorsCarl-Erik TROILI, Tomas WESTERLUND
Life of this patent
Estimating the term…
Abstract
The present disclosure relates to a method for non-invasive determination of a hemodynamic parameter of a mechanically ventilated subject (3) based on a point in time (thb) of a heartbeat of the subject and an arrival point in time (tarr_pulm, taff_sys) at which a blood pressure pulse caused by the heartbeat reaches a point of arrival in the circulatory system of the subject. The method comprises the steps of measuring (S41) a respiratory pressure and/or a respiratory flow, and determining (S43) the point in time (thb) of the heartbeat from a change in the measured respiratory pressure and/or the respiratory flow resulting from a physical impact of the heart on the lungs of the subject (3) during the heartbeat.
Claims26
1-44. (canceled)
A method for non-invasive determination of a hemodynamic parameter of a mechanically ventilated subject based on a point in time (thb) of a heartbeat of the subject and an arrival point in time (tarr_pulm, tarr_sys) at which a blood pressure pulse caused by the heartbeat reaches a point of arrival in the circulatory system of the subject, comprising:
- obtaining a respiratory pressure and/or a respiratory flow;
- determining the point in time (thb) of the heartbeat from a change in the measured respiratory pressure and/or the respiratory flow resulting from a physical impact of the heart on the lungs of the subject during the heartbeat;
- determining:
- a pulmonary pulse transit time, PTTpulm, for the blood pressure pulse based on the point in time of the heartbeat (thb) and a point in time of arrival (tarr_pulm) of the blood pressure pulse to the lungs of the subject;
- and/or
- a systemic pulse transit time, PTTsys, for the blood pressure pulse based on the point in time of the heartbeat (thb) and a point in time of arrival (tarr_sys) of the blood x-pressure pulse to a point of arrival in the systemic circulatory system of the subject;
- and
- determining the hemodynamic parameter based on PTTpulm and/or PTTsys.
A ventilation system for non-invasive determination of a hemodynamic parameter of a mechanically ventilated subject based on a point in time (thb) of a heartbeat of the subject and an arrival point in time (tarr_pulm, tarr_sys) at which a blood pressure pulse caused by the heartbeat reaches a point of arrival in the circulatory system of the subject, the ventilation system comprising:
- a breathing apparatus mechanically ventilating the subject;
- at least one pressure sensor measuring a respiratory pressure and/or at least one flow sensor measuring a respiratory flow;
- and
- a computer determining the hemodynamic parameter,
- wherein the computer is configured to:
- determine the point in time (thb) of the heartbeat from a change in the measured respiratory pressure and/or the respiratory flow resulting from a physical impact of the heart on the lungs of the subject (3) during the heartbeat;
- determine:
- a pulmonary pulse transit time, PTTpulm, for the blood pressure pulse based on the point in time of the heartbeat (thb) and a point in time of arrival (tarr_pulm) of the blood pressure pulse to the lungs of the subject;
- and/or
- a systemic pulse transit time, PTTsys, for the blood pressure pulse based on the point in time of the heartbeat (thb) and a point in time of arrival (tarr_sys) of the blood pressure pulse to a point of arrival in the systemic circulatory system of the subject;
- and
- determine the hemodynamic parameter based on PTTpulm and/or PTTsys.
Dependencies are inferred from the claim text.