Medical tubes for breathing circuit
A breathing circuit for use in respiratory therapy includes an inspiratory tube and an expiratory tube. The inspiratory tube of the breathing circuit has a smooth bore. The expiratory tube of the breathing circuit is corrugated. Preferably, the expiratory tube is vapor permeable. Using the combination of a smooth bore inspiratory tube with a corrugated expiratory tube has the unexpected result of improving the performance of the breathing circuit and its components.
1 . A breathing circuit comprising a combination of an inspiratory tube and an expiratory tube, the breathing circuit configured for use in respiratory therapy for a patient, the breathing circuit comprising:
the inspiratory tube configured to receive an inspiratory gases flow from a gas source, the inspiratory tube comprising an inspiratory inlet, an inspiratory outlet, and a wall enclosing an inspiratory central bore, wherein the inspiratory central bore of the inspiratory tube is smooth;
the expiratory tube configured to receive an expiratory gases flow from a patient, the expiratory tube comprising an expiratory inlet, an expiratory outlet, and a wall enclosing an expiratory central bore, wherein the expiratory central bore of the expiratory tube is corrugated; and
a connector that in use connects the inspiratory outlet and the expiratory inlet to a patient interface to transfer the inspiratory gases flow to the patient and the expiratory gases flow from the patient;
the inspiratory tube having an inner diameter between 9 mm and 13 mm and the expiratory tube having a nominal inner diameter between 13 mm and 19 mm.
2 . The breathing circuit of claim 1 , wherein the connector comprises a y piece configured for coupling the inspiratory tube and the expiratory tube.
3 . The breathing circuit of claim 1 , further comprising a chamber configured for holding a quantity of water and configured to be positioned on a humidifier.
4 . The breathing circuit of claim 1 , further comprising a dry line configured for conveying flow from the gas source to a humidifier inlet.
5 . The breathing circuit of claim 1 , the inspiratory tube having an inner diameter between 9 mm and 10 mm, or having an inner diameter between 11 mm and 13 mm, or having an inner diameter between 10 mm and 13 mm, or having an inner diameter between 8 mm and 13 mm.
6 . The breathing circuit of claim 1 , the expiratory tube having a nominal inner diameter between 13 mm and 15 mm, or having a nominal inner diameter between 13 mm and 16 mm, or having a nominal inner diameter between 14 mm and 18 mm, or having a nominal inner diameter between 16 mm and 19 mm, or having a nominal inner diameter between 14 mm and 19 mm.
7 . The breathing circuit of claim 1 , the inspiratory tube or expiratory tube having a length between 1.5 m and 2.5 m or having a length between 1.6 m and 2.5 m.
8 . The breathing circuit of claim 1 , wherein the inspiratory tube comprises a heating element within the inspiratory central bore or within the wall.
9 . The breathing circuit of claim 1 , wherein the expiratory tube comprises a heating element.
10 . The breathing circuit of claim 1 , wherein the expiratory tube is breathable.
11 . The breathing circuit of claim 1 , wherein the wall of the expiratory tube is permeable to water molecules and substantially impermeable to liquid and bulk flow of the expiratory gases flow flowing therethrough.
12 . The breathing circuit of claim 1 , wherein the inspiratory tube comprises in longitudinal cross-section a plurality of bubbles, each bubble comprising a flattened surface forming at least part of the wall of the inspiratory central bore.
13 . The breathing circuit of claim 1 , wherein the circuit kit breathing circuit is suitable for treatment of patients having tidal volumes in a range of 50 ml to 300 ml for pediatric patients.
14 . The breathing circuit of claim 1 , wherein the circuit kit breathing circuit is suitable for treatment of pediatric and adolescent patients.
15 . The breathing circuit of claim 1 , wherein a difference between the inner diameter of the inspiratory tube and the nominal inner diameter of the expiratory tube is between 1 mm and 10 mm.
16 . The breathing circuit of claim 1 , wherein at least one of the inspiratory tube and the expiratory tube comprises multiple sections to accommodate other equipment, wherein the other equipment comprises a water trap, an intermediate connector with one or more sensors, a PCB, or a controller.
17 . The breathing circuit of claim 1 , the inspiratory tube having an inner diameter of 11.7 mm.
18 . The breathing circuit of claim 1 , wherein the inspiratory gases flow received by the inspiratory tube are delivered to the patient and the expiratory gases flow received by the expiratory tube comprises at least a portion of any gases delivered to and exhaled by the patient.
19 . A breathing circuit comprising a combination of an inspiratory tube and an expiratory tube, the breathing circuit configured for use in respiratory therapy for a patient, the breathing circuit comprising:
the inspiratory tube configured to receive an inspiratory gases flow from a gas source, the inspiratory tube comprising an inspiratory inlet, an inspiratory outlet, and a wall enclosing an inspiratory central bore, wherein the inspiratory central bore of the inspiratory tube is smooth;
the expiratory tube configured to receive an expiratory gases flow from a patient, the expiratory tube comprising an expiratory inlet, an expiratory outlet, and a wall enclosing an expiratory central bore, wherein the expiratory central bore of the expiratory tube is corrugated; and
a connector that in use connects the inspiratory outlet and the expiratory inlet to a patient interface to transfer the inspiratory gases flow from the inspiratory tube to the patient and to transfer the expiratory gases flow from the patient to the expiratory tube;
the inspiratory tube having an inner diameter between 9 mm and 13 mm and a length, and the expiratory tube having a nominal inner diameter between 13 mm and 19 mm and a length, wherein the breathing circuit is suitable for treatment of pediatric and neonatal patients.