Preface

Endotracheal intubation is the most important component of airway management and is of vital importance. Airway management is a complicated medical practice in which many medical disciplines are involved. These medical disciplines include anesthesiology, emergen‐ cy medicine, critical care, pulmonary medicine, and surgery. Various examinations, maneu‐ vers, and positions may also be required for tracheal intubation. In addition, if the tracheal intubation could not be performed, surgical intervention should be implemented and oxy‐ genation should be provided by tracheotomy or cricothyrotomy. Thus, if intubation difficulty is predicted in medical situations where the airway opening should be provided, or if intuba‐ tion is not possible, a "difficult airway algorithm" should be used for life-saving procedures. In this book, the medical basis of hypoxia and oxygenation, functional airway anatomy and physiology, and difficult airway management are described. I am grateful to the authors for their contributions to this book and hope that this book will be helpful to the readers.

#### **Prof.Dr.Riza Hakan Erbay, M.D.**

Chairman of Department of Anesthesiology and Reanimation Faculty of Medicine Pamukkale University Denizli, Turkey

**Section 1**

**Functional Anatomy and Phsiology of Airway**

**Functional Anatomy and Phsiology of Airway**

**Chapter 1**

**Provisional chapter**

**Functional Anatomy and Physiology of Airway**

**Functional Anatomy and Physiology of Airway**

DOI: 10.5772/intechopen.77037

In this chapter, we scope the importance of functional anatomy and physiology of the upper airway. The upper airway has an important role in transporting air to the lungs. Both the anatomical structure of the airways and the functional properties of the mucosa, cartilages, and neural and lymphatic tissues influence the characteristics of the air that is inhaled. The airway changes in size, shape, and position throughout its development from the neonate to the adults. Knowledge of the functional anatomy of the airway in these forms the basis of understanding the pathological conditions that may occur. The upper airway extends from the mouth to the trachea. It includes the mouth, the nose, the palate, the uvula, the pharynx, and the larynx. This section also describes the functional physiology of this airway. Managing the airway of a patient with craniofacial disorders poses many challenges to the anesthesiologist. Anatomical abnormalities may affect only intubation, only airway management, or both. This section also focuses on the abnormal airways in obesity, pregnancy, children and neonate, and patients with abnormal facial

**Keywords:** anatomy, airway, function, physiology, upper airway

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

The upper airway has an important role in conducting air to the lungs. Both the anatomical structure of the airways and the functional properties of the mucosa, cartilages, and neural and lymphatic tissues influence the characteristics of the air that is inhaled [1]. The upper airways begin with the nasal cavity and continue over nasopharynx and oropharynx to the larynx and the extrathoracic part of the trachea. The structure and function of this system have a major influence upon the conduction of the air to the lower airways [1]. Functions of the airway include phonation, olfaction, digestion, humidification, and warming of inspired

Aslı Mete and İlknur Hatice Akbudak

Aslı Mete and İlknur Hatice Akbudak

http://dx.doi.org/10.5772/intechopen.77037

**Abstract**

defects.

**1. Introduction**

Additional information is available at the end of the chapter

Additional information is available at the end of the chapter

#### **Functional Anatomy and Physiology of Airway Functional Anatomy and Physiology of Airway**

DOI: 10.5772/intechopen.77037

#### Aslı Mete and İlknur Hatice Akbudak Aslı Mete and İlknur Hatice Akbudak

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.77037

#### **Abstract**

In this chapter, we scope the importance of functional anatomy and physiology of the upper airway. The upper airway has an important role in transporting air to the lungs. Both the anatomical structure of the airways and the functional properties of the mucosa, cartilages, and neural and lymphatic tissues influence the characteristics of the air that is inhaled. The airway changes in size, shape, and position throughout its development from the neonate to the adults. Knowledge of the functional anatomy of the airway in these forms the basis of understanding the pathological conditions that may occur. The upper airway extends from the mouth to the trachea. It includes the mouth, the nose, the palate, the uvula, the pharynx, and the larynx. This section also describes the functional physiology of this airway. Managing the airway of a patient with craniofacial disorders poses many challenges to the anesthesiologist. Anatomical abnormalities may affect only intubation, only airway management, or both. This section also focuses on the abnormal airways in obesity, pregnancy, children and neonate, and patients with abnormal facial defects.

**Keywords:** anatomy, airway, function, physiology, upper airway

#### **1. Introduction**

The upper airway has an important role in conducting air to the lungs. Both the anatomical structure of the airways and the functional properties of the mucosa, cartilages, and neural and lymphatic tissues influence the characteristics of the air that is inhaled [1]. The upper airways begin with the nasal cavity and continue over nasopharynx and oropharynx to the larynx and the extrathoracic part of the trachea. The structure and function of this system have a major influence upon the conduction of the air to the lower airways [1]. Functions of the airway include phonation, olfaction, digestion, humidification, and warming of inspired

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

air [2]. Clinical application of anatomical and physiological knowledge of respiratory system improves patient's safety during anesthesia [3]. This chapter focuses on airway anatomy and physiology, which form the basis for airway management and endotracheal intubation, and also for anesthesiologists.

provides protection which is of the shape of the middle third part of the nose and supports the nasal valve. The lower lateral cartilage segments are butterfly shaped and consist of medial and lateral crures. The medial crus forms the columellar, while the lateral crus forms the nasal area. These crures together form the nasal vestibule deficit. Cartilage is supported by nasal septum [6]. The nasal cavity is divided into two compartments by the nasal septum. One of them opens out into the nostrils. The other compartment is the nasopharynx, which opens to the concha or the posterior nasal opening. The vestibule, which includes the nostrils between the small flat nose hairs, is a small aperture [5]. **The nasal septum** divides the nasal cavity into two separate compartments. It consists of an anterior cartilaginous portion, which provides support for the nasal tip, and a posterior bony portion formed by the perpendicular plate of the ethmoid and the vomer (**Figure 2**) [6]. Deviations of the septum are very common; in fact, they are present to some degree in about 75% of the adult population. When the rapid growth in this region, septal cartilage, occurs from an unspecified minor dislocation, the deformity as often as the appearance of the second tooth structure often does not manifest itself. A distribution that supports this traumatic theory is that men are more often affected than women [5]. Due to the possibility of septum deviation, before passing instrumentation, through the nasal passages, the more open side should be determined [4]. The lateral wall of the nasal passages includes **the turbinates (the concha).** These are three, rarely four, scroll-like projections from the lateral nasal wall. The lower two, referred to as the inferior and middle turbinates, are functionally the most significant. Each turbinate consists of a bony frame with the overlying respiratory epithelium

Functional Anatomy and Physiology of Airway http://dx.doi.org/10.5772/intechopen.77037 5

The **inferior meatus**, between the inferior turbinate and the floor of the nasal cavity, is the preferred pathway for the passage of nasal airway devices [4]. The cribriform plate, part of

(**Figure 3**) [6].

**Figure 2.** Nasal Sinuses.
