Pulmonary Vascular Response to Sodium Nitroprusside in Anesthetized Dogs

Chloralose anesthetized, spontaneously breathing, normoxic and hypoxic closed-chest dogs previously instrumented to record pulmonary arterial pressure and flow.

Sodium nitroprusside (SNP) administered as a continuous IV infusion across 7 doses, evaluated before and after sympathetic blockade with propranolol and phentolamine, and during hypoxia (breathing 5% O2).

Control state (baseline prior to SNP infusion).

Pulmonary hemodynamics and total calculated pulmonary vascular resistance.surrogate