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Determinants of Lymph Flow
• The degree of activity of the lymphatic pump
- smooth muscle filaments in lymph vessel cause them to contract
- external compression also contributes to lymphatic pumping
Figure 16-11; Guyton and Hall
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Determinants of Lymph Flow
Interstitial fluid hydrostatic pressure Lymph Flow
Figure 16-9; Guyton and Hall
Figure 16-10; Guyton and Hall
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Factors affecting Central Venous Pressure
Figure 15-9; Guyton and Hall
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NORMAL
HYPEREFFECTIVE
-4 0 +4 +8
25
20
15
10
5
0
CA
RD
IAC
OU
TP
UT
(L
/min
)
RIGHT ATRIAL PRESSURE (mmHg)
HYPOEFFECTIVE
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Copyright © 2006 by Elsevier, Inc.
• Plateau of CO curve determined by heart strength (contractility + HR) Sympathetics
plateau Parasympathetics (HR)
Plateau
• Heart hypertrophy ’s plateau
• Myocardial infarction plateau)
• Plateau
The Cardiac Output Curve
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• Point at which plateau occurs on CO curve is determined by heart strength (contractility and HR)
Sympathetics plateau
Parasympathetics (HR) plateau)
Heart hypertrophy ’s plateau
Myocardial infarction plateau)
The Cardiac Output Curve
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Arterial Baroreceptor Reflex
Blood Pressure
ArterialBaroreceptors
VasomotorCenter
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Response of the Baroreceptors to Arterial Pressure
Figure 18-6; Guyton and Hall
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Response of the Baroreceptors to Pressure
Constrict
Common Carotids
Constrictors
Pressure at
Carotid Sinuses Arterial Pressure
Figure 18-5; Guyton and Hall Figure 18-7; Guyton and Hall
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Functions of the Baroreceptors• Maintains relatively constant pressure despite changes in
body posture.
DecreaseCardiac Output
Sensed ByBaroreceptors
Supine StandingDecreaseCentral
Blood Volume
VasomotorCenter
SympatheticNervous Activity
DecreaseArterial Pressure