Key Points
- This research aims to explore how hemorrhagic shock affects the reactivity of resistance and capacitance vessels in cat skeletal muscle.
- Assessment of vascular responses to sympathetic stimulation and norepinephrine infusion in cat skeletal muscle.
- Comparison of pre-capillary and post-capillary resistance responses during hemorrhagic shock.
- Evaluation of fluid movement across capillary membranes under different shock conditions.
- Resistance vessel reactivity declines faster than capacitance responses during shock.
- Nerve stimulation causes a net inward movement of fluid before pre-capillary responses are abolished.
- Restoration of vascular reactivity occurs after blood replacement, though time in shock affects outcomes.
Structured PICO
PPopulationCat skeletal muscle model
IInterventionHemorrhagic shock with regional lumbar sympathetic vasoconstrictor nerve fiber stimulation and close intra-arterial infusion of l-norepinephrine
CComparatorBaseline state (pre-shock) and after replacement of shed blood
OOutcomeReactivity of resistance and capacitance vessels and capillary filtration transfersurrogate
In a cat model of hemorrhagic shock, the differential loss of pre-capillary versus post-capillary vascular reactivity to sympathetic stimulation leads to a decompensatory loss of capillary fluid, providing a physiological rationale for sympatholytic therapy in late shock.