Methods, systems and devices for non-invasive ventilation including a non-sealing ventilation interface with an entrainment port and/or pressure feature
Systems and methods may include a gas source, a gas delivery circuit, and a nasal interface allowing breathing ambient air through the nasal interface. A gas flow path through the nasal interface may have a distal gas flow path opening. A nozzle may be associated with a proximal end of the nasal interface a distance from the distal end gas flow path opening. At least a portion of an entrainment port may be between the nozzle and the distal end gas flow opening. The nozzle may deliver gas into the nasal interface to create a negative pressure area in the gas flow path at the entrainment port. The nasal interface and the nozzle may create a positive pressure area between the entrainment port and the distal end gas flow path opening. Gas from the gas delivery source and air entrained through the entrainment port may increase airway pressure or lung pressure or provide ventilatory support.
1. A ventilation system comprising:
a ventilator; and
a patient ventilation interface in fluid communication with the ventilator, the patient ventilation interface comprising:
an outer tube having an outlet at a distal end and an entrainment aperture open to ambient air at a proximal end; and
a nozzle for delivering gas from the ventilator into the outer tube, the nozzle disposed completely proximal to the entrainment aperture.
2. The system of claim 1 , wherein the patient ventilation interface comprises a nasal interface and the outer tube is dimensioned to fit at least partially inside a patient's nostril.
3. The system of claim 2 , wherein the outer tube comprises a nasal cushion.
4. The system of claim 1 , wherein the outer tube has a cross section that expands from the proximal end to the distal end.
5. The system of claim 1 , wherein the outer tube has a constant cross section from the proximal end to the distal end.
6. The system of claim 1 , wherein the delivery of the gas by the nozzle creates a positive pressure area within a velocity profile defined by the ventilation gas delivered by the nozzle.
7. The system of claim 6 , wherein the velocity profile intersects the outer tube at a position proximal to the outlet.
8. The system of claim 6 , wherein the delivery of the gas by the nozzle creates a negative pressure area having an annular cross-section between the velocity profile and the outer tube.
9. The system of claim 8 , wherein the entrainment aperture is disposed within the negative pressure area.
10. The system of claim 1 , wherein the nozzle is concentric to the outer tube.
11. The system of claim 1 , wherein the nozzle is angled relative to the outer tube.
12. The system of claim 1 , wherein the nozzle is positioned in parallel with the entrainment aperture in relation to a gas flow direction.
13. The system of claim 1 , wherein the patient ventilation interface is adapted to connect to the ventilator with tubing having an outer diameter of 3-7 mm.
14. A patient ventilation interface comprising:
an outer tube having an outlet at a distal end and an entrainment aperture open to ambient air at a proximal end; and
a nozzle for delivering gas from a ventilator into the outer tube, the nozzle disposed completely proximal to the entrainment aperture.
15. The patient ventilation interface of claim 14 , wherein the patient ventilation interface comprises a nasal interface and the outer tube is dimensioned to fit at least partially inside a patient's nostril.
16. The patient ventilation interface of claim 15 , wherein the outer tube comprises a nasal cushion.
17. The patient ventilation interface of claim 14 , wherein the nozzle is positioned in parallel with the entrainment aperture in relation to a gas flow direction.
18. A ventilation system comprising:
a ventilator; and
a patient ventilation interface in fluid communication with the ventilator, the patient ventilation interface comprising:
an outer tube having an outlet at a distal end and an entrainment aperture open to ambient air at a proximal end; and
a nozzle for delivering gas from the ventilator into the outer tube, the nozzle disposed equidistantly between a proximal end and a distal end of the entrainment aperture.