New medical circuit components and methods for forming such components are disclosed. These components include microstructures for humidification and/or condensate management. The disclosed microstructures can be incorporated into a variety of components, including tubes (e.g., inspiratory breathing tubes and expiratory breathing tubes and other tubing between various elements of a breathing circuit, such as ventilators, humidifiers, filters, water traps, sample lines, connectors, gas analyzers, and the like), Y-connectors, catheter mounts, humidifiers, and patient interfaces (e.g., masks for covering the nose and face, nasal masks, cannulas, nasal pillows, etc.), floats, probes, and sensors in a variety of medical circuits.