Abstract
Background
Existing porcine models of endotoxic shock poorly represent the human situation.
Aims
To assess whether the cardiovascular profile of a porcine model could be improved by refining the protocol.
Methods
In 30 pigs, right and left heart pressures and cardiac output were measured. Lipopolysaccharide (LPS) was administered as a bolus (n=12), as a 30 minute infusion (n=6) or as a 30 minute infusion along with inhaled NO and volume resuscitation (n=6) and six sham-treated pigs received normal saline. Haemodynamic values were measured over three hours.
Results
LPS increased pulmonary vascular resistance (PVR) (13.3±1.4 to 37.0±3.9kPa/l per sec, p< 0.05) and reduced cardiac output (6.0±0.6 to 4.8±0.4l/min). Mortality was 50% within 30 minutes. Inhaled NO and volume resuscitation controlled pulmonary vascular resistance (PVR) and preserved CO. Systemic vascular resistance (SVR) declined in the first hour (118.4±11.8 to 65.8±8.2kPa/l per sec, p< 0.05) and remained low.
Conclusions
Porcine models of endotoxaemia based on LPS administration are a poor model of human septic shock, but can be improved by regulating PVR and supporting CO which may contribute to future studies of septic shock
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Herity, N.A., Allen, J.D., Silke, B. et al. Inhaled nitric oxide in combination with volume resuscitation refines a porcine model of endotoxic shock. Ir J Med Sci 170, 172–175 (2001). https://doi.org/10.1007/BF03173883
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DOI: https://doi.org/10.1007/BF03173883