Cannula for minimizing dilution of dosing during nitric oxide delivery

A nasal cannula for therapeutic gas delivered to a patient in need thereof, comprising:

• a first lumen, a second lumen, and a third lumen:
• the first lumen being a first therapeutic gas lumen for delivering a first therapeutic gas to a patient,
• the second lumen being a triggering lumen for triggering release of a pulse of the first therapeutic gas, and
• the third lumen being a second therapeutic gas lumen for delivering a second therapeutic gas to the patient;
• the first therapeutic gas lumen, the triggering lumen, and the second therapeutic gas lumen aggregating at a cannula nosepiece, the cannula nosepiece allowing separate flow paths to the patient for each of the first therapeutic gas lumen, the triggering lumen, and the second therapeutic gas lumen;
• and
• the first therapeutic gas lumen having an inner diameter that is (i) smaller than an inner diameter of the second therapeutic gas lumen and an inner diameter of the triggering lumen and (ii) larger than an inner diameter of the flow path for the first therapeutic gas lumen at the cannula nosepiece.

A nasal cannula for therapeutic gas delivered to a patient, comprising:

• a first lumen, a second lumen, and a third lumen:
• the first lumen being a first therapeutic gas lumen for delivering nitric oxide gas to a patient,
• the second lumen being a triggering lumen, and
• the third lumen being a second therapeutic gas lumen for delivering one or more of oxygen gas and air gas to the patient;
• the first therapeutic gas lumen, the triggering lumen, and the second therapeutic gas lumen aggregating at a cannula nosepiece, the cannula nosepiece allowing separate flow paths to the patient for each of the first therapeutic gas lumen, the triggering lumen, and the second therapeutic gas lumen;
• the flow path for the first therapeutic gas lumen for delivering nitric oxide to the patient having a volume defined by the region extending between exits of a first and second nasal cannula nare at the cannula nosepiece that is less than about 10% of a minimum pulse volume of the pulse of nitric oxide;
• the first therapeutic gas lumen having an inner diameter that is smaller than an inner diameter of the second therapeutic gas lumen and an inner diameter of the triggering lumen;
• and
• the first therapeutic gas lumen having an inner diameter that is larger than an inner diameter of the flow path for the first therapeutic gas lumen at the cannula nosepiece.

A method for treating pulmonary hypertension, comprising:

• administering nitric oxide gas to a patient through a nasal cannula, wherein the nasal cannula comprises:
• a first lumen, a second lumen, and a third lumen:
• the first lumen being a first therapeutic gas lumen for delivering a nitric oxide gas to a patient,
• the second lumen being a triggering lumen for sensing the onset of inspiration or a change in pressure, and
• the third lumen being a second therapeutic gas lumen for delivering oxygen gas to the patient;
• and
• a cannula nosepiece aggregating, and allowing separate flow paths to the patient for, each of (i) the first therapeutic gas lumen, (ii) the triggering lumen, and (iii) the second therapeutic gas lumen;
• wherein the first lumen has an inner diameter that is smaller than an inner diameters of the second lumen and third lumen but larger than an inner diameter of the flow path for the first lumen at the cannula nosepiece.