Devices and methods for treating lung tumors

A system for ablative treatment of a targeted lung tissue, the system comprising:

• an ablation energy source;
• a source of conductive hypertonic saline solution having a concentration of at least 5% of sodium chloride by weight/volume;
• a catheter configured to advance through a natural airway passage of a lung and position a distal portion of the catheter within the airway passage and proximate a target area of the lung,
• an ablation element coupled to the distal portion and configured to receive energy from the ablation energy source and deliver the energy into the airway passage proximate the target area;
• a temperature sensor coupled to the distal portion;
• an irrigation port on the distal portion in fluid communication with the source of conductive hypertonic saline solution and configured to dispense the hypertonic saline solution into the airway passage of the lung, and
• a controller configured to:
• control delivery of energy from the ablation element into the airway passage to ablate lung tissue in the target area;
• monitor a temperature proximate the temperature sensor using data generated by the temperature sensor;
• control infusion of the conductive hypertonic saline solution through the irrigation port into the airway passage during the delivery of the energy, wherein the control of the infusion includes:
• infusing the conductive hypertonic saline solution at a first rate or first bolus during a first period of a cycle and infusing the conductive hypertonic saline solution at a second rate or second bolus during a second period of the cycle, wherein the first rate is greater than the second rate or the first bolus is greater than the second bolus,
• switching between the first period and the second period in the cycle based on the temperature, and
• repeating the cycle until the target area is ablated by the delivery of the energy from the ablation element.