Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.
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Transcript of Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.
![Page 1: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/1.jpg)
HemodynamikkHemodynamikk
Hans TorpFysiologi og Biomedisinsk Teknikk
NTNU
![Page 2: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/2.jpg)
HemodynamicsHemodynamics
• Hemo from Hemo from Haima =Haima = Blood Blood
• Dynamics from Dynamics from Dynamis ~ Dynamis ~ force which results in force which results in
motionmotion
• Blood pressure -> Blood flowBlood pressure -> Blood flow
Voltage
current
![Page 3: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/3.jpg)
Normal blood pressure is not Normal blood pressure is not sufficientsufficient
Voltage
current
![Page 4: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/4.jpg)
Relation Relation blood pressure / blood flowblood pressure / blood flow
• Blood pressure = Blood flow * periferal resistance Blood pressure = Blood flow * periferal resistance
• periferal resistance increases by narrowing of periferal resistance increases by narrowing of
capillariescapillaries
• Blood flow to an organ may have substaial variation, Blood flow to an organ may have substaial variation,
with a constant blood pressure with a constant blood pressure
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Blood flow – low periferal Blood flow – low periferal resistanceresistance
Blood pressure
Blood flow
![Page 6: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/6.jpg)
Blood flow – high periferal Blood flow – high periferal resistanceresistance
Blood pressure
Blood flow
Spill film
![Page 7: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/7.jpg)
Hastighet [cm/s] versus volumstrøm Hastighet [cm/s] versus volumstrøm [ml/s][ml/s]
V1
A1
Blodmengde som passerer areal A1: Q1 = V1 * A1
Hastighet V1 måles med Doppler , areal A1 måles på ultralydbilde
Eksempel: V1= 30 cm/s , A1= 0.3 cm^2, Q1 = 9 ml/s = 54 ml/min
![Page 8: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/8.jpg)
Stenosis assessmentStenosis assessment
V1 V2
A1 A2
V1 * A1 = V2 * A2
% reduksjon A1 - A2 = V2 - V1 A1 V2
Example:
5x velocitycorresponds to
80% stenose
Degree of stenosis can be calculatet without angle correction
![Page 9: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/9.jpg)
Stenose + lekkasje i aortaklaffStenose + lekkasje i aortaklaff
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Pressure gradient in a stenosisPressure gradient in a stenosis
V1 V2
P1 P2
Bernouli’s equation: P1 - P2 = 4 V2 - 4 V1 2 2V [m/s]
P [mmHg]
Hans TorpNTNU, Norway
![Page 11: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/11.jpg)
Fall i blodtrykk ved stenoseFall i blodtrykk ved stenose
V1 V2
P1 P2
Bernouli’s ligning: P1 - P2 = 4 V2 - 4 V1 2 2
Significant stenosis (V2 >>V1) : P1 - P3 = 4 V2
Cinetic energy loss due to turbulence
P3
2
Hans TorpNTNU, Norway
![Page 12: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/12.jpg)
Pressure gradient in a stenosisPressure gradient in a stenosis
V1 V2
P1 P2
Trykk - fall (gradient) : P1 - P3 = 4 V2
P3
2
Eksempel: 80% aorta-stenoseV1= 1 m/s V2 = 5 m/s gir trykk-gradient 4*5*5 = 100 mmHg
Hans TorpNTNU, Norway
![Page 13: Hemodynamikk Hans Torp Fysiologi og Biomedisinsk Teknikk NTNU.](https://reader035.fdocuments.net/reader035/viewer/2022062219/551a6f5055034643688b5026/html5/thumbnails/13.jpg)
V1 V2
P1 P2
Bernouli’s equation Pressure gradient: P1 - P3 = 4 V22
P3
Example: 80% aortic-stenosisV1= 1 m/s V2 = 5 m/s ~ pressure gradient of 4*5*5 = 100 mmHg
Left ventricular pressure of 220 mmHg is required to achieve 120 mmHg aothic pressure
Hans TorpNTNU, Norway
Pressure gradient in a stenosisPressure gradient in a stenosis