Flow sensor for ventilation

A flow sensor system for assisting resuscitative treatment, comprising:

• a flow conduit configured to be placed in a patient airway and having a lumen that accommodates gas flow between a first region and a second region;
• a flow restrictor disposed within the lumen of the flow conduit between the first region and the second region, the flow restrictor comprising at least one flap in a sensitive region of the flow sensor system;
• and
• at least one pressure sensor configured to measure gas pressure of at least one of the first region and the second region of the flow conduit,
• wherein the at least one flap exhibits a greater level of hydrophobicity than a neighboring region adjacent to the at least one flap,
• wherein the at least one flap is disposed in the lumen of the flow conduit and the at least one flap is configured to deflect bi-directionally due to gas flow through the flow restrictor in either direction, and
• wherein the neighboring region includes a reservoir comprising at least a tapered portion of the lumen and at least a portion of the flow restrictor adjacent to the at least one flap, the reservoir being configured to collect water arising from gas flowing through the lumen and the neighboring region is configured to wick away water from the sensitive region to the reservoir.