Effects of Inhaled Nitric Oxide on Hypoxic Pulmonary Vasoconstriction in Dogs and a Case Report of Venae Cavae Syndrome

Abstract

We investigated the effect of inhaled nitric oxide (NO) on hypoxic pulmonary vasoconstriction (HPV) in dogs, by treating a dog suffering from venae cavea syndrome (VCS) and pulmonary hypertension (PH) with NO inhalation. The increasing mean pulmonary arterial pressure (mPAP) induced by hypoxia was lessened significantly by NO inhalation. High PAP in VCS also declined as a result of NO inhalation. These results suggested that inhaled NO can reverse HPV in dogs and prevent worsening PH during surgical extraction of heartworm in VCS.