At first glance the nose seems like a small insignificant part of the body. It doesn’t pump blood like the heart. It doesn’t think and reason, like the brain. It doesn’t aid in reproduction, nor does it digest food.” Yet the nose and “its components are just as important as those other vital organs for keeping each of us alive. (1)
In other words, the nose plays a pivotal role with regards to the airway, temperature and humidity, air filtration, smell-taste and as a resonator.
Airway
The nose is a rigid passageway that allows air to pass into the lower respiratory tract. In infancy, air passing through the nose is the primary way how the infant gets oxygen into the lungs. If there’s a significant nasal deformity or blockage in the back of the nose causing air hunger, surgery may be vital to save the infant’s life. In adults, nasal obstruction in compromised patients can also have life threatening consequences. The heart, brain and other organ systems cannot survive without oxygen and it’s important to note how air is delivered to the lungs.
Temperature & humidity regulation
The nose is the organ that delivers air to the surfaces of the lung at an ideal temperature and humidity. The nasal membrane inside the nose has a rich supply of blood with a remarkable ability for heating or cooling the inhaled air in spite of the temperature outside.
Imagine being outside in Jackson Hole, Wyoming when the temperature drops to 10 degrees F below zero or in Las Vegas, Nevada when the temperature rises to 112 degrees F in the shade. Our body cannot survive for long using the air at these temperatures. But the nose consistently regulates the temperature of the inspired air so that in the back of the throat it is only one or two degrees above or below the body temperature of 98.6 F regardless of the outside temperature! It does a remarkable job as well in regulating the humidity (between 75 and 80 percent) that reaches the lung’s surfaces by giving up moisture from the mucous blanket. (1)
Air Filtration
The nose is a self-cleansing structure that uses tiny hair cells called cilia and mucous to trap and remove unwanted foreign substances from the inspired air. This “mucociliary” activity continuously removes and propels unwanted particles and sinus drainage towards the back of the throat through the esophagus (food passage) into the stomach and G.I. tract. Mucous also contains Immunoglobulin A (IgA) an antibody that plays a role in the body’s defense mechanism.
Smell & Taste
As air passes through the nasal passageway we can determine whether the aroma of a delicious meal is on its way or the odor of a gas leak tells us it’s time to get away. The nerve cells for the sense of smell (olfactory nerve) are located in the upper-back part of the nose and they send signals that go directly to the brain. The nerve cells for the sense of taste (gustatory nerve) are located in the taste buds of the tongue, mouth and throat.
It is obvious to everyone who has experienced the common cold that the sense of smell is closely associated with the sense of taste. For example, if you pinch your nose you’ll have more difficulty identifying the flavor of certain foods.
Resonator
The nasal cavity or “nasal tract” contributes to the timbre or tone quality of the voice. It’s the quality that makes your voice sound different from that of another person. The function of the nasal tract as a resonator is apparent to all, but especially worrisome to the singer who is suffering from a common cold or other nasal conditions.
Rhinosinusitis
Almost without exception, sinusitis is preceded by an inflammation of the nasal airway passageway. Rhinosinusitis is an inflammation of the nose as well as the sinuses.
SUMMARY
The nose plays a vital role in our well-being. The septum, made of cartilage and bone, divides the nose into the right and left sides. There are three bony structures called turbinates on each side of the nose that help warm and direct the flow of air to the back of the throat. Every two or three hours one side of the turbinates swells while the other side shrinks referred to as the “nasal cycle.”
Mucous covers surface of the nasal cavity and sinuses like a blanket. The sinuses open into the nasal cavity. Understanding the functions of the nose (and their interrelationships) is the first step in knowing what to do when things go wrong with the sinus. . Future articles will deal with sinusitis.
- Jordan Josephson, MD; Sinus Relief Now; Perigee Book.