BP Tree of life

• Cardiac output
• "blood flow"
• volume of blood ejected with each cardiac contraction

Stroke Volume

• Preload
• Contractility
• Afterload

• Stretching of ventricles before contraction
• largely function of venous return

Force of ventricular contraction

Force needed to overcome aortic pressure and achieve left ventricular outflow

balance between input from SNS & PNS

Sympathetic nervous system

Parasympathetic nervous system

• Systemic Vascular Resistance
• Resistance of blood flow through body's blood vessels

Increases

decreases

Local and systemic mediatora

• Vasopressin
• Angiotensin
• SNS

• releases catecholamines (hormones made by adrenal glands on top of kidneys)
• Primarily responsible for basal systemic vascular tone - min to min regulation of BP

• Causes vasoconstriction
• More long-term regulation of vascular tone

• NO
• CO2
• Histamine
• PGs

Nitric Oxide

Carbon Dioxide

• Prostaglandins
• Lipid compounds derived from arachidonic acid, have varying hormone-like effects

Change in metabolic demand, muscle activity, vascular injury, and to circumvent systemic vascular control

• NO
• CO2
• Histamine
• Prostacyclin (PG)

• Endothelin
• Thrombin
• Thromboxane (PG released from plts)