Key result
Patients with severe alcoholic liver cirrhosis failed to increase their pulmonary vascular resistance during inspiratory hypoxia, unlike control subjects who showed significant increases.
Why the study?
Does hypoxia induce normal pulmonary vasoconstriction in patients with severe liver cirrhosis compared to controls?
Observational (n=28)
No
Does hypoxia induce normal pulmonary vasoconstriction in patients with severe liver cirrhosis compared to controls?
Patients with liver cirrhosis lack normal hypoxic pulmonary vasoconstriction, which may explain the paradoxical combination of arterial hypoxemia and low pulmonary vascular resistance in this population.
Answers are grounded in this paper and cite their sources.
Impaired hypoxic vasoconstriction may underlie hypoxemia despite low PVR in cirrhosis; leaves open causality and applicability beyond alcoholic disease.
The combination of arterial hypoxemia and low pulmonary vascular resistance in patients with liver cirrhosis is unexplained. Pulmonary microcirculatory dilation, but not gross arterio-venous shunts, has been the usual postmortem finding in patients with liver cirrhosis. When 10 patients with alcoholic liver cirrhosis breathed 10% oxygen in nitrogen, they failed to increase their pulmonary vascular resistance. However, four patients with functional murmurs, three patients with hyperkinetic heart syndrome, six patients with normal pulmonary artery pressures and intracardiac left to right shunts, and five patients with renal failure and anemia all increased their pulmonary vascular resistances when they breathed 10% oxygen in nitrogen. These findings suggested that in liver cirrhosis the normal regulating mechanism (hypoxic vasoconstriction) of the pulmonary circulation may be impaired, resulting in failure of the lung to match perfusion with ventilation.
No takes yet. Share an insight, caveat, or question.
Daoud et al. (1972) conducted an observational in Liver cirrhosis (n=28). Inspiratory hypoxia (8-14% O2) vs. Room air was evaluated on Pulmonary vascular resistance during hypoxia (units) (p=<0.05). Patients with severe alcoholic liver cirrhosis failed to increase their pulmonary vascular resistance during inspiratory hypoxia, unlike control subjects who showed significant increases.
Synapse has enriched 10 related papers. Consider them for comparative context: