Minimally invasive determination of collateral ventilation in lungs

Abstract

Minimally invasive methods, systems and devices are provided for qualitatively and quantitatively assessing collateral ventilation in the lungs. In particular, collateral ventilation of a target compartment within a lung of a patient is assessed by advancement of a catheter through the tracheobronchial tree to a feeding bronchus of the target compartment. The feeding bronchus is occluded by the catheter and a variety of measurements are taken with the use of the catheter in a manner which is of low risk to the patient. Examples of such measurements include but are not limited to flow rate, volume and pressure. These measurements are used to determine the presence of collateral ventilation and to quantify such collateral ventilation.

What is claimed is: 
     
         1 . A method for determining the function or malfunction of an endobronchial prosthesis positioned within a lung passageway of a patient, said method comprising:
 occluding the lung passageway proximally of the endobronchial prosthesis;   allowing the patient to breathe air without any markers; and   measuring air flow or accumulation from the lung passageway over time wherein said measurement is correlative to the function or malfunction of the endobronchial prosthesis.   
     
     
         2 . A system for detecting collateral ventilation into a lung compartment in a patient, said system comprising:
 a catheter adapted to be introduced transtracheally to a bronchus leading to a target lung compartment;   an occlusion member on a distal region of the catheter, said occlusion member being adapted to selectively occlude the bronchus; and   a flow measurement sensor on the catheter to detect flow of air from the isolated compartment as the patient exhales.   
     
     
         3 . A system for detecting collateral ventilation into a lung compartment in a patient, said system comprising:
 a catheter adapted to be introduced transtracheally to a bronchus leading to a target lung compartment;   an occlusion member or a distal region of the catheter, said occlusion member being adapted to selectively occlude the bronchus; and   an accumulator connectable to the catheter to accumulate air exhaled from the catheter over time.   
     
     
         4 . A system as in  claim 3 , wherein the accumulator comprises a slack collection bag which has substantially no resistance to filling with air. 
     
     
         5 . A treatment guide to determine a course of treatment for a lung compartment of a patient, the guide comprising:
 a plurality of hyperinflation values, each hyperinflation value representing a degree of hyperinflation of the lung compartment, and/or a plurality of compliance values, each compliance value representing a degree of compliance of the lung compartment; and   a plurality of treatment options, wherein each treatment option is correlated to a hyperinflation value and/or a compliance value.   
     
     
         6 . A treatment guide as in  claim 5 , wherein the guide comprises a computer program. 
     
     
         7 . A treatment guide as in  claim 6 , wherein the computer program includes at least one mathematical computation to generate the plurality of hyperinflation values and/or the plurality of compliance values. 
     
     
         8 . A treatment guide as in  claim 7 , wherein the mathematical computation utilizes pressure and concentration of inert gas values. 
     
     
         9 . A method of evaluating collateral ventilation of a target lung compartment of a patient, the method comprising:
 positioning an instrument within a lung passageway leading to the target lung compartment so that the target lung compartment is isolated;   allowing the patient to inhale air;   generating at least one measurement of at least one characteristic of the inhaled air within or exiting the target lung compartment with the use of the instrument; and   determining a level of collateral ventilation into the target lung compartment based on the at least one measurement.   
     
     
         10 . A method as in  claim 9 , wherein the at least one characteristic includes volumetric flow rate. 
     
     
         11 . A method as in  claim 9 , wherein the at least one characteristic includes pressure. 
     
     
         12 . A method as in  claim 9 , wherein determining a level of collateral ventilation includes calculating a value of collateral resistance. 
     
     
         13 . A method as in  claim 9 , further comprising determining a treatment plan based on the level of collateral ventilation. 
     
     
         14 . A method of evaluating a patient for treatment of a target lung compartment, the method comprising:
 generating at least one measurement associated with the target lung compartment while the patient is breathing air;   calculating a level of collateral ventilation into the target lung compartment based on the at least one measurement; and   treating the patient based on the calculated level of collateral ventilation.   
     
     
         15 . A method as in  claim 14 , wherein treating the patient comprises aspirating the target lung compartment. 
     
     
         16 . A method as in  claim 14 , wherein treating the patient comprises occluding a lung passageway feeding the target lung compartment. 
     
     
         17 . A method as in  claim 16 , wherein occluding comprises positioning an occlusal stent within the lung passageway. 
     
     
         18 . A method as in  claim 14 , wherein calculating comprises calculating a value of collateral resistance based on the at least one measurement. 
     
     
         19 . A treatment guide to determine a course of treatment for a lung compartment of a patient, the guide comprising:
 a plurality of collateral resistance values, each value representing degree of collateral ventilation of the lung compartment; and   a plurality of treatment options, wherein each treatment option is correlated to a collateral resistance value.   
     
     
         20 . A treatment guide as in  claim 19 , wherein the guide comprises a computer program. 
     
     
         21 . A treatment guide as in  claim 20 , wherein the computer program includes at least one mathematical computation to generate the plurality of collateral resistance values. 
     
     
         22 . A treatment guide as in  claim 21 , wherein the mathematical computation utilizes pressure and volumetric flow rate values. 
     
     
         23 . A treatment guide as in  claim 22 , wherein the guide includes a visual display showing a curve representing a relationship between the collateral resistance values and a combination of the pressure and volumetric flow rates. 
     
     
         24 . A system as in  claim 2 , wherein the catheter comprises a one-way valve which blocks air flow into the target lung compartment and permits air flow from the compartment to the atmosphere. 
     
     
         25 . A system as in  claim 3 , wherein the catheter comprises a one-way valve which blocks air flow into the target lung compartment and permits air flow from the compartment to the atmosphere.