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CHAPTER 20 Caring for Clients With Upper Respiratory Disorders

now. Negative modes include iron lungs or respirator tanks, or pneumowrap and chest cuirass (a plastic shell-like appa ratus that fits over the chest). The second classification, positive pressure ventilators, are more commonly used. These types of ventilators inflate the lungs by exerting positive pressure, pushing air into the airway. Positive pressure ventilators generally require intu bation and are used for clients with acute respiratory failure and primary lung disease, such as cystic fibrosis, or for cli ents who are comatose, are under general anesthesia, or have extensive upper airway edema. Complications related to me chanical ventilation include damage to the lungs, decreased lung expansion, and ventilator-associated pneumonia (VAP). Table 20-2 briefly describes the types of positive pressure ventilators. Accidental removal of an endotracheal tube must be prevented because this can result in laryngeal edema or la ryngospasm (spasm of the laryngeal muscles, resulting in narrowing of the larynx) and subsequent respiratory arrest. The inflated cuff and placement of tape around the tube at tached to the client’s cheek secures the endotracheal tube. The proximal end of the tube is marked for determining whether downward displacement has occurred. The intubated client has the endotracheal tube re moved when the vital capacity is adequate and the client can breathe without assistance. Blood gas studies are also used as a guideline for removal. Depending on hospital policy,

Figure 20-7 Endotracheal tubes.

ventilation of the lungs. Humidification is necessary because air going to the lungs through an endotracheal tube does not pass through the moist mucous membranes of the upper airway. There are several modes of mechanical ventilation clas sified according to the way they support ventilation. Two major classifications are negative pressure and positive pres sure ventilators. Negative pressure ventilators exert negative pressure, a pulling or sucking force, on the external chest. Although widely used at one time for clients with chronic respiratory failure related to neuromuscular disease such as poliomyelitis or myasthenia gravis, this mode is rarely used TABLE 20-2 Types of Positive Pressure Ventilators TYPE OF POSITIVE PRESSURE VENTILATORS HOW USED Positive pressure ventilator—general information

Exerts positive pressure on airway to inflate lungs; expiration is passive Usually requires endotracheal or tracheal intubation

Pressure-cycled positive pressure ventilator

Inspiration ends when a preset pressure is reached; cycle means that ventilator cycles on, delivers flow of air until a certain pressure is reached, and then cycles off. Designed for short-term use because volume of air varies as client’s airway resistance or compliance changes Controls respiration after a preset time; length of inspiration and flow rate of air regulate volume the client receives; usually used on newborns and infants Delivers a preset volume of air with each inspiration; once volume is delivered, ventilator cycles off and client expires air passively. Provides consistent adequate breaths despite airway resistance or changes in compliance; most commonly used ventilator for adults Ventilator cycles between higher and lower pressure levels of CPAP. This helps to open alveoli and promotes better gas exchange. Clients require less sedation on and can maintain a cough reflex. Clients have potential for earlier removal (weaning) from the ventilator. Ventilation delivered by face masks or other nasal devices; does not require intubation of any kind; used for clients with sleep-related breathing disorders or other chronic respiratory disorders. Provides positive pressure to airways throughout respiration. It is sometimes used for intubated clients being weaned from ventilators, or is used with masks to maintain alveoli patency. Clients must be able to breathe on their own for this modality.

Time-cycled positive pressure ventilator Volume-cycled positive pressure ventilator

Airway pressure release ventilation (APRV)

Noninvasive positive pressure venti lator (NIPPV) Continuous positive airway pressure (CPAP)

Copyright © 2025 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. Provides positive pressure support ventilation with independent control of inspiratory and expira tory pressures. Clients use a nasal or oral mask or a mouthpiece with a tight seal. The client initi ates each inspiration or the machine will because it has a backup mode, ensuring that the client receives a set number of breaths per minute. Clients with severe COPD or sleep apnea use this type of support ventilation. Bilevel positive airway pressure (BiPAP)

COPD, chronic obstructive pulmonary disease. Adapted from Hinkle, J. L., Cheever, K. H., & Overbaugh, K. (2021). Brunner & Suddarth’s textbook of medical-surgical nursing (15th ed.). Wolters Kluwer.