Did you know that adult humans only have a tenth of a second to get the airway closed prior to a bolus of liquid entering the upper part of the esophagus or food and liquid will go down the “wrong pipe” (aka trachea)?
Not a lot of room for error. Most of us have personally experienced the mis-timed swallow either privately or witnessed by others, often when we are talking or otherwise distracted. This hazard is not often experienced by babies, small children or animals because of what I would call “nature’s anatomical protection”, with the hyoid and larynx more closely approximated and in an elevated position and tucked under the base of the tongue, as compared to older individuals. In humans, due to the dual function of the larynx for communication and swallowing, the larynx and hyoid descend as we mature, making the airway more precarious for aspiration but allowing for complex communication and differentiating us from the animals.
continue reading →