A needleless connector caps is provided with one or more vents allowing air to pass around the cap, for example in a case where a cap may be accidentally lodged in a position completely concentric with a patient's throat. Configuration of structural elements making up a cap exterior can provide one or more openings or channels in the cap that remain unblocked and extend from the base to the top side of the cap forming one or more vents allowing air to pass through the cap.