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Description of a Swine Infant Model of Volume-Controlled Hemorrhagic Shock
Published on: November 3, 2023
Venous blood for the analysis of acid-base status in a model of septic shock
Matthew J Maiden1,2,3, Jonathan D Fraser1,2, Mark E Finnis1,2
1Intensive Care Unit, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
Objective:
To determine the relationship between arterial and venous acid-base status in a model of septic shock.
Methods:
Paired samples (n = 435) of arterial and femoral venous blood from 57 sheep (47 septic, 10 non-septic) managed with protocol-guided ventilation, sedation, parenteral fluids and inotropic support.
Results:
The arterial-venous difference in acid-base parameters was similar with and without sepsis. There was a consistent arterio-venous relationship for metabolic (pH, lactate, bicarbonate, base excess), but not respiratory parameters (partial pressures of oxygen, carbon dioxide, and haemoglobin-oxygen saturation), independent of sepsis.
Conclusions:
Venous blood provides a reliable measure of metabolic but not respiratory disturbance.
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