Deck 2: The Upper and Lower Airway and Associated Structures

Question 1

A 36-year-old man was taken to the emergency department after having been found lying unresponsive in a local park with an empty whisky bottle nearby. He was given oxygen by an open face mask during the 15minute ride in the ambulance. The paramedic decided to improve the airway by passing a soft nasal tube. On attempting to pass the well-lubricated tube into the patient's nose, the paramedic found it impossible to push it much beyond the nasal vestibule on either side. What are the common anatomic causes of obstruction of the nasal airway?

Answer 1

The most common cause for difficulty in passing a nasal tube is a deflected nasal septum. This occurs more commonly in the male, and is thought to be due to previous trauma to the septum during the period of active growth. Nasal spurs and polyps may cause difficulty and swelling of the mucous membrane secondary to infection or chemical irritation, and can also cause blockage. The widest part of the nasal cavity is near the floor.

Question 2

A 12-year-old girl was brought to the hospital with a history of fever, malaise, anorexia, and a sore throat. She also had hoarseness, a cough, and rhinitis. On examination there was erythema of the posterior pharyngeal wall, with small ulcers on the palatoglossal folds and soft palate. The tonsils were seen to be red and enlarged, and an obvious white-yellow exudate was seen on the surface of the left tonsil. Examination of the deep cervical lymph nodes showed enlargement and tenderness of the node below and behind the angle of the mandible; the enlargement was greatest on the left side. A diagnosis of viral pharyngitis was made. List the various lymphoid organs found in the nasal and oral parts of the pharynx. Explain Waldeyer's ring.

Answer 2

The lymphoid tissue around the openings of the mouth and nasal cavities into the pharynx include (1) the palatine tonsil, (2) the lingual tonsil, (3) the tubal tonsils, and (4) the pharyngeal tonsil. For details of Waldeyer's ring, see text Chapter 2.

Question 3

A 3-year-old boy was playing with his toys on the floor when his sister decided to share some peanuts with him. A few minutes later he started to cough and gave a hoarse cry. The cough then became croupy, and aphonia occurred. The mother, hearing the commotion, rushed into the room and quickly realized what had happened. She turned the child upside down and hit his back several times, but with no effect. The child, now in obvious respiratory distress, was rushed to the local emergency department. On examination, he was tachypneic, with suprasternal retractions. He was not coughing, and although he attempted to cry, there was no sound. He would not tolerate being laid down. On the basis of your knowledge of the anatomy of the airway, where do you think the foreign body was lodged? Describe the normal protective reflexes that exist in the airway to prevent the inhalation of a foreign body. What is the anatomic and physiologic rationale behind the use of back blows, chest thrusts, and abdominal thrusts (Heimlich procedure) in the management of upper airway obstruction? Which of these procedures is most appropriate for a 3-year-old child?

Answer 3

The presence of severe respiratory distress with suprasternal retractions and aphonia indicates the presence of upper airway obstruction, probably located within the larynx. The airway is protected by a number of important reflexes, including the gag reflex, the laryngeal reflex, and the cough reflex. The gag reflex occurs in response to stimulation of the pharyngeal mucous membrane innervated by the glossopharyngeal nerve. The laryngeal and the cough reflexes are mediated via the vagus nerve. These protective reflexes are lost in descending order as a patient loses consciousness.
All maneuvers that are directed toward freeing an obstruction of the airway by an inhaled foreign body are based on an attempt to increase the intrathoracic pressure by compressing the intrathoracic gas volume, so that the foreign body is expressed from the mouth. The underlying mechanisms involved in the use of back blows, chest thrusts, and abdominal thrusts are discussed in this CD chapter. It is now generally agreed that the best and safest method to use on a 3-year-old child is the abdominal thrust.

Question 4

A 17-year-old boy was driving his minibike at high speed along a country lane, when he suddenly saw what he thought was a shortcut through a gap in a hedge. He did not see that the gap was closed by a strand of barbed wire. He struck the wire with his neck and was thrown from the bicycle. On arrival at the emergency department, he had all the signs and symptoms of upper airway obstruction. Using your knowledge of the anatomy of the neck, explain the type of injury that could have occurred in this case. Does the position of the vocal cords at the time of impact influence the type of injury that occurs? What anatomic factors normally protect
the upper airway from serious blunt injuries? Does age play a role in the severity of the injury?

Question 5

A 39-year-old man with extensive maxillofacial injuries following an automobile accident was brought to the hospital. Evaluation of the airway revealed partial obstruction. Despite an obvious fractured mandible, an attempt was made to move the tongue forward from the posterior pharyngeal wall by pushing the angles of the mandible forward. This maneuver failed to move the tongue, and it became necessary to hold the tongue forward directly in order to pull it away from the poste- rior pharyngeal wall. At times, why is it not possible to pull the tongue forward in the presence of a fractured mandible?

Question 6

When a laryngoscope is passed it is important to align the mouth, the oropharynx, and the larynx into one plane. How do you bring the axes of the oropharynx and the larynx in line? How do you bring the axis of the mouth in line with the other axes? Describe the structures in the order that you can view them through a laryngoscope from the base of the tongue down to the trachea.