A controlled reactor for use in making pharmaceutical nitric oxide for inhalation by a patient. The reactor including a cassette having a hydrophilic porous substrate coated and impregnated with a particulate reductant such as croconic acid. The reactor also including a piezoelectric print head for atomizing and pulsing small droplets of an aqueous solution containing nitrite ions, non-detergent surfactant, and, viscosity agent. The reactor used to provide controlled delivery of pharmaceutical nitric oxide gas to a controlled patient inhalation delivery system that may include a mechanical ventilator circuit.
