Larynx – Conducting Zone (Nursing)

00:01 So starting with the larynx, which is the most superior portion of the lower respiratory tract just after the pharynx.

00:09 They have three main functions.

00:11 The first is to provide a patent airway or basically an open and clear passage for air.

00:20 The larynx is also going to route air and food into their proper channels.

00:26 This happens by way of a structure known as the epiglottis.

00:30 The epiglottis is going to be open during speech.

00:34 But when you swallow your food the epiglottis closes so that food does not get into the respiratory tract.

00:42 So what happens when you talk and eat at the same time sometimes our food goes down the wrong pipe.

00:48 This is what happens when epiglottis is open while you are swallowing.

00:55 The third function of the larynx is going to be voice production and this takes place using the house vocal folds.

01:05 So if we look a little bit closer at voice production, we find that speech is the intermittent release of expired air during the opening and closing of a structure known as the glottis.

01:18 The glottis includes the vocal folds as well as the space in between these two folds.

01:25 We also refer to the vocal folds as the vocal cords.

01:32 When it comes to pitch or the pitch of your voice, soprano or base, your vocal cords are attached to laryngeal muscles.

01:41 These laryngeal muscles are going to create a tension that is like the tuning of a string instrument.

01:48 The pitch is going to be determined by the length and the tension of these vocal cords as they are being pulled by these laryngeal muscles.

02:00 While pitch is determined by tension loudness of sound is going to be determined by the force of air that goes through the glottis.

02:11 So along with the larynx, we also have chambers of the pharynx the oral nate, oral cavity, the nasal cavity and the sinus cavities that are all going to take part in amplifying enhancing sound quality.

02:28 We shape our sound into language or speech by the muscles of the pharynx as well as the tongue, the soft palate and the lips.

02:39 So speech is like a coordinated dance between all of these structures.

02:46 The larynx can also serve a sphincters function.

02:51 In this case the vocal folds may act as a sphincter in order to prevent air passage.

02:58 A good example of this is the valsalva maneuver.

03:01 During this, the glottis is going to close in order to prevent air from exhaling or being released from the air passage.

03:12 At the same time the abdominal muscles are going to contract and these two processes cause the intra-abdominal pressure to increase.

03:24 Together this will help do things like empty the rectum or in the case of heavy lifting like in weightlifting, stabilizing the trunk.

03:33 So if you've ever noticed in weightlifting when a person lifts weights, a lot of times, it looks like they're holding their breath and they actually sometimes have to be reminded to breathe so they don't pass out.

03:44 This is due to the valsalva maneuver.