Venous pressure testing apparatus, non-transitory computer readable storage medium, and venous pressure testing method

1 . A venous pressure testing apparatus for estimating a central venous pressure of a target person by measuring a venous pulse by a cuff sensor at a predetermined measurement position of the target person, comprising:

at least one processor configured to estimate that the central venous pressure of the target person is lower than a predetermined reference venous pressure if the venous pulse is not detected by the cuff sensor at the predetermined measurement position of the target person,

wherein the target person has a particular posture,

wherein the reference venous pressure coincides with a hydrostatic pressure corresponding to an elevation difference between the heart of the target person and a peak elevation of a vein,

wherein the vein leads from the heart to the measurement position, and

wherein the at least one processor is configured to set a cuff pressure of the cuff sensor at the reference venous pressure.

2 . The venous pressure testing apparatus according to claim 1 , wherein the at least one processor is configured to estimate that the central venous pressure of the target person is higher than or equal to the reference venous pressure if the venous pulse is detected by the cuff sensor at the measurement position of the target person who assumes the particular posture.

3 . The venous pressure testing apparatus according to claim 2 , wherein the at least one processor is configured to:

receive the reference venous pressure; and

specify the particular posture of the target person based on the received reference venous pressure.

4 . The venous pressure testing apparatus according to claim 3 , wherein the particular posture is an angle formed by an upper part and a lower part of a body of the target person whose arms hang down.

5 . A venous pressure testing apparatus for estimating a central venous pressure of a target person by measuring a venous pulse by a sensor at a predetermined measurement position of the target person, comprising:

at least one processor configured to estimate that the central venous pressure of the target person is lower than a received predetermined reference venous pressure if the venous pulse is not detected by the sensor at the predetermined measurement position of the target person,

wherein the target person has a particular posture,

wherein the reference venous pressure coincides with a hydrostatic pressure corresponding to an elevation difference between the heart of the target person and a peak elevation of a vein,

wherein the vein leads from the heart to the measurement position

wherein the at least one processor estimates that the central venous pressure of the target person is higher than or equal to the reference venous pressure if the venous pulse is detected by the sensor at the measurement position of the target person who assumes the particular posture,

wherein the particular posture of the target person is specified based on the received reference venous pressure,

wherein the particular posture is an angle formed by an upper part and a lower part of a body of the target person whose arms hang down, and

wherein the at least one processor is configured to cause the target person to assume the particular posture by setting a bend angle of a back contact surface, the back contact surface being in contact with the back of the target person, of a posture guide tool capable of adjusting the angle formed by the upper part and the lower part of the body of the target person by bending the back contact surface, at the angle formed by the upper part and the lower part of the body of the target person that has been specified as the particular posture by the specification unit.

6 . The venous pressure testing apparatus according to claim 4 , wherein the at least one processor is configured to specify the particular posture based on a length of a line segment drawn on a body surface of the target person so as to connect respective points corresponding to the heart and the peak point and an angle formed by the line segment and a horizontal direction.

7 . The venous pressure testing apparatus according to claim 6 , wherein the at least one processor is configured to:

receive body information of the target person; and

calculate the length of the line segment drawn on the body surface of the target person so as to connect the respective points corresponding to the heart and the peak point based on the received body information.

8 . The venous pressure testing apparatus according to claim 4 , wherein the at least one processor is configured to:

detect an angle formed by the upper part and the lower part of the body of the target person as a posture of the target person based on an output of an angle sensor which detects an angle formed by the upper part and the lower part of the body of the target person; and

estimate that the central venous pressure of the target person is lower than the reference venous pressure if the venous pulse is not detected by the sensor at the measurement position of the target person when the detected posture is the particular posture.

9 . The venous pressure testing apparatus according to claim 3 , wherein the particular posture is an angle formed by an upper part of a body and an upper arm of the target person who lies on his or her back with the upper arm raised toward the vertical direction.

10 . The venous pressure testing apparatus according to claim 3 , wherein the particular posture is an angle formed by an upper part and a lower part of the body of the target person who has raised an upper arm above the heart toward the vertical direction and an angle formed by the upper arm and the upper part of the body.

11 . The venous pressure testing apparatus according to claim 3 , further comprising a display unit which displays the particular posture.

12 . The venous pressure testing apparatus according to claim 2 , wherein:

the measurement position is an upper arm; and

the at least one processor is configured to estimate that the central venous pressure of the target person is lower than the reference venous pressure if the venous pulse is not detected by the cuff that is attached to the upper arm of the target person and the cuff pressure of which is set at the reference venous pressure, and estimate that the central venous pressure of the target person is higher than or equal to the reference venous pressure if the venous pulse is detected by the cuff.

13 . The venous pressure testing apparatus according to claim 12 , wherein the at least one processor is configured to vary the cuff pressure from the reference venous pressure and estimates that a cuff pressure obtained when the venous pulse has a maximum amplitude is a central venous pressure.

14 . A non-transitory computer readable storage medium that stores a venous pressure testing program for testing a central venous pressure of a target person by measuring a venous pulse by a cuff sensor at a predetermined measurement position of the target person, the venous pressure testing program causing a computer to execute processing of:

estimating that the central venous pressure of the target person is lower than a predetermined reference venous pressure if the venous pulse is not detected by the cuff sensor at the measurement position of the target person who assumes a particular posture with which a water-gauge pressure corresponding to a vertical distance between the heart of the target person and a peak point, in the vertical direction, of a vein leading from the heart to the measurement position coincides with the reference venous pressure; and

setting a cuff pressure of the cuff sensor at the reference venous pressure.

15 . A venous pressure testing method for estimating a central venous pressure of a target person by measuring a venous pulse by a cuff sensor at a predetermined measurement position of the target person, comprising:

an estimation step of estimating that the central venous pressure of the target person is lower than a predetermined reference venous pressure if the venous pulse is not detected by the cuff sensor at the measurement position of the target person who assumes a particular posture with which a water-gauge pressure corresponding to a vertical distance between the heart of the target person and a peak point, in the vertical direction, of a vein leading from the heart to the measurement position coincides with the reference venous pressure; and

a step of setting a cuff pressure of the cuff sensor at the reference venous pressure.