Ch. 20 Reading

Question 1

goal of oxygen therapy is to provide a sufficient concentration of inspired oxygen to permit full use of the oxygen-carrying capacity of the arterial blood; this ensures adequate cellular oxygenation, provided that the cardiac output and hemoglobin concentration are adequate.
Principles of therapy
Methods of delivery
Complications of oxygen therapy
Nursing management

Answer 1

Oxygen Therapy

Question 2

The concentration of oxygen given to an individual patient is a clinical judgment based on the many factors that influence oxygen transport, such as hemoglobin concentration, cardiac output, and arterial oxygen tension.
After oxygen therapy has begun, the patient is continuously assessed for level of oxygenation and the factors affecting it. The patient’s oxygenation status is evaluated several times daily until the desired oxygen level has been reached and has stabilized.

Answer 2

Principles of therapy

Question 3

Common problems with these devices include system leaks and obstructions, device displacement, and skin irritation.
Low-flow systems
Reservoir systems
High-flow systems

Answer 3

Methods of delivery

Question 4

provides supplemental oxygen directly into the patient’s airway at a flow of 8 L/min or less.
this method of oxygen delivery results in a variable FIO2 as the supplemental oxygen is mixed with room air. The patient’s ventilatory pattern affects the FIO2 of a low-flow system: As this pattern changes, differing amounts of room air gas are mixed with the constant flow of oxygen.
EX: nasal cannula

Answer 4

Low-flow systems

Question 5

incorporates some type of device to collect and store oxygen between breaths. When the patient’s inspiratory flow exceeds the oxygen flow of the oxygen delivery system, the patient is able to draw from the reservoir of oxygen to meet his or her inspiratory volume needs.A reservoir oxygen delivery system can deliver a higher FIO2 than a low-flow system. Examples of reservoir systems are simple face masks, partial rebreathing masks, and nonrebreathing masks.

Answer 5

Reservoir systems

Question 6

oxygen flows out of the device and into the patient’s airways in an amount sufficient to meet all inspiratory volume requirements.
An air-entrainment mask is an example of a high-flow system that delivers precisely controlled oxygen at the lower FIO2 range.
One newer high-flow system is the high-flow nasal cannula.

Answer 6

High-flow systems

Question 7

Oxygen toxicity
Carbon dioxide retention
Absorption atelectasis - Breathing high concentrations of oxygen washes out the nitrogen that normally fills the alveoli and helps hold them open (residual volume).

Answer 7

Complications of oxygen therapy

Question 8

Breathing high concentrations of oxygen washes out the nitrogen that normally fills the alveoli and helps hold them open (residual volume)

Answer 8

Nursing management

Question 9

Pharyngeal airways
Endotracheal tubes (ETT)
Tracheostomy tubes
Nursing management

Answer 9

Artificial Airways

Question 10

used to maintain airway patency by keeping the tongue from obstructing the upper airway. Complications of these airways include trauma to the oral or nasal cavity, obstruction of the airway, laryngo-
spasm, gagging, and vomiting.
Oropharyngeal airway
Nasopharyngeal airway

Answer 10

Pharyngeal airways

Question 11

The proper size is selected by holding the airway against the side of the patient’s face and ensuring that it extends from the corner of the mouth to the angle of the jaw. If the airway is improperly sized, it will occlude the airway.
When properly placed, the tip of the airway lies above the epiglottis at the base of the tongue. An oropharyngeal airway is used only in an unconscious patient who has an absent or diminished gag reflex.

Answer 11

Oropharyngeal airway

Question 12

The proper size is selected by holding the airway against the side of the patient’s face and ensuring that the nasopharyngeal airway extends from the tip of the nose to the ear lobe. A nasal airway is placed by lubricating the tube and inserting it midline along the floor of the naris into the posterior pharynx. When properly placed, the tip of the airway lies above the epiglottis at the base of the tongue.

Answer 12

Nasopharyngeal airway

Question 13

providing short-term airway management.
Indications for endotracheal intubation include maintenance of airway patency, protection of the airway from aspiration, application of positive-pressure ventilation, facilitation of pulmonary hygiene, and use of high oxygen concentrations.
Complications
including nasal and oral trauma, pharyngeal and hypopharyngeal trauma, vomiting with aspiration, and cardiac arrest
Tracheal rupture is a rare and often fatal complication that is associated with emergent intubation. Hypoxemia and hypercapnia can also occur, resulting in bradycardia, tachycardia, dysrhythmias, hypertension, and hypotension.
Several complications can occur while the ETT is in place, including nasal and oral inflammation and ulceration, sinusitis and otitis, laryngeal and tracheal injuries, and tube obstruction and displacement. Other complications can occur days to weeks after the ETT is removed, including laryngeal and tracheal stenosis and a cricoid abscess

Answer 13

Endotracheal tubes (ETT)

Question 14

preferred method of airway maintenance in a patient who requires long-term intubation formed. A tracheostomy is also indicated in several other situations such as the presence of an upper airway obstruction secondary to trauma, tumors, or swelling and the need to facilitate airway clearance secondary to spinal cord injury, neuromuscular disease, or severe debilitation.
A tracheostomy tube provides the best route for long-term airway maintenance, because this route avoids the oral, nasal, pharyngeal, and laryngeal complications associated with an ETT. The tube is shorter, has a wider diameter, and is less curved than an ETT; the resistance to airflow is less; and breathing is easier.
include ease with secretion removal, increased patient acceptance and comfort, capability of the patient to eat and talk if possible, and easier ventilator weaning.
Single-lumen tubes consist of the tube; a built-in cuff, which is connected to a pilot balloon for inflation purposes; and an obturator, which is used during tube insertion. Double-lumen tubes consist of the tube with the attached cuff, the obturator, and an inner cannula that can be removed for cleaning and then reinserted or, if disposable, replaced by a new sterile inner cannula.
Complications
including misplacement of the tracheal tube, hemorrhage, laryngeal nerve injury, pneumothorax, pneumomediastinum, and cardiac arrest.
while the tracheostomy tube is in place, including stomal infection, hemorrhage, tracheomalacia, tracheoesophageal fistula, tracheoinnominate artery fistula, and tube obstruction and displacement. Many complications can occur days to weeks after the tracheostomy tube is removed, including tracheal stenosis and tracheocutaneous fistula

Answer 14

Tracheostomy tubes

Question 15

Last, observing the patient to ensure proper placement of the tube and patency of the airway is essential.
Patient safety is of paramount importance when caring for a patient with an artificial airway, because loss of the tube can result in loss of the patient’s airway.
If the tracheostomy remains open, consideration is given to ventilating the patient through the stoma instead of the mouth.
Humidification
prevent drying and irritation of the respiratory tract, to prevent undue loss of body water, and to facilitate secretion removal.
Cuff management
Only low-pressure, high-volume cuffed tubes are used in clinical practice.
Proper cuff inflation techniques and cuff pressure monitoring are critical components of the care of a patient with an artificial airway.
Suctioning
Communication
Oral hygiene
Extubation and decannulation

Answer 15

Nursing management

Question 16

often required to maintain a patent airway in a patient with an ETT or tracheostomy tube. Suctioning is a sterile procedure that is performed only when the patient needs it and not on a routine schedule. Indications for suctioning include the presence of coarse crackles over the trachea on auscultation, coughing, visible secretions in the airway, a sawtooth pattern on the flow-volume loop on the ventilator monitor, increased peak airway pressures on the ventilator, decreasing oxygenation saturation, and acute respiratory distress.
Complications: hypoxemia, atelectasis, bronchospasms, dysrhythmias, increased intracranial pressure, and airway trauma.
The open suction method requires disconnecting the patient from the ventilator
The closed suction method requires a sterile, closed tracheal suction system (CTSS) and allows the patient to remain on the ventilator when suctioned; preferable, (limit the hypoxemia)
For shallow suctioning, the suction catheter is inserted to the end of the ETT or tracheostomy tube, and then the suction is applied.
For deep suctioning, the suction catheter is inserted until resistance is met, the catheter is pulled back approximately 1 cm, and then suction is applied. Evidence suggests that shallow suctioning is as effective as deep suctioning for secretion removal and is associated with fewer complications.

Answer 16

Suctioning

Question 17

include establishing an environment that fosters communication, performing a complete assessment of the patient’s ability to communicate, anticipating the patient’s needs, teaching the patient and family how to communicate, using a variety of methods to communicate, and facilitating the patient’s ability to communicate by providing the patient with his or her eyeglasses or hearing aid.
include the use of verbal and nonverbal language and various devices to assist the patient on short-term and long-term ventilator assistance.
Nonverbal communication may include the use of sign language, gestures, lip reading, pointing, facial expressions, or eye blinking. Simple devices include pencil and paper; Magic Slates; magnetic boards with plastic letters; picture, alphabet, or symbol boards; and flash cards. More sophisticated devices include typewriters, computers, talking ETT and tracheostomy tubes, and external handheld vibrators. Regardless of the method selected, the patient must be taught how to use the device.
Passy-Muir valve is a device used to assist a mechanically ventilated patient with a tracheostomy to speak. This one-way valve opens on inhalation, allowing air to enter the lungs and closes on exhalation, permitting the patient to speak

Answer 17

Communication

Question 18

Patients with artificial airways are extremely susceptible to developing VAP because of microaspiration of subglottic secretions. These secretions are full of microorganisms from the patient’s mouth. Because the cuff of the artificial airway does not form a tight seal in the patient’s airway, these secretions seep around the cuff into the patient’s lungs, promoting the development of VAP.

Answer 18

Oral hygiene

Question 19

Extubation, the process of removing an ETT, is a simple procedure that can be done at the bedside.46 Before the cuff of an ETT or tracheostomy tube is deflated in preparation for removal, it is important to ensure that secretions are cleared from above the tube cuff.
Complications of extubation include sore throat, stridor,
hoarseness, odynophagia, vocal cord immobility, pulmonary
aspiration, and cough.
Decannulation is the process of removing a tracheostomy tube. This is also a simple process that can be performed at the bedside. After removal of the tracheostomy tube, the stoma is usually covered with a dry dressing with the expectation that it will close within several days. Difficulty removing the tracheostomy tube because of a tight stoma is usually the only complication associated with decannulation.

Answer 19

Extubation and decannulation

Question 20

Types of ventilators
Ventilator mechanics

Answer 20

Invasive Mechanical Ventilation

Question 21

two main types of ventilators available at the present time are (1) positive-pressure ventilators and (2) negative pressure ventilators. Negative pressure ventilators are applied externally to the patient and decrease the atmospheric pressure surrounding the thorax to initiate inspiration. They generally are not used in the critical care environment. Positive-pressure ventilators use a mechanical drive mechanism to force air into the patient’s lungs through an ETT or tracheostomy tube.

Answer 21

Types of ventilators

Question 22

properly ventilate the patient, the ventilator must complete four phases of ventilation: (1) change from exhalation to inspiration, (2) inspiration, (3) change from inspiration to exhalation, and (4) exhalation.
Trigger
Limit
Cycle
Baseline

Answer 22

Ventilator mechanics

Question 23

phase variable that initiates the change from exhalation to inspiration is called the trigger. Breaths may be pressure triggered or flow triggered, depending on the sensitivity setting of the ventilator and the patient’s inspiratory effort, or they may be time triggered, depending on the rate setting of the ventilator.
A time-triggered breath is a machine-controlled breath that is initiated by the ventilator after a preset length of time has elapsed and is controlled by the rate setting on the ventilator
Flow-triggered and pressure-triggered breaths are patient-assisted breaths that are initiated by decreased flow or pressure, respectively, within the breathing circuit.

Answer 23

Trigger

Question 24

The variable that maintains inspiration is called the limit or target. Inspiration can be pressure limited, flow limited, or volume limited. A pressure-limited breath is one in which a preset pressure is attained and maintained during inspiration. A flow-limited breath is one in which a preset flow is reached before the end of inspiration. A volume-limited breath is one in which a pre-set volume is delivered during the inspiration. However, the limit variable does not end inspiration; it only sustains it.

Answer 24

Limit

Question 25

The variable that ends inspiration is called the cycle.
Volume-cycled ventilators are designed to deliver a breath until a preset volume is delivered. Pressure-cycled ventilators deliver a breath until a preset pressure is reached with-in the patient’s airways. Flow-cycled ventilators deliver a breath until a preset inspiratory flow rate is achieved. Time-cycled ventilators deliver a breath over a preset time interval.

Answer 25

Cycle

Question 26

The variable that is controlled during exhalation is called the baseline.
The baseline variable may be set at zero (i.e., atmospheric pressure) or above atmospheric pressure (i.e., PEEP).

Answer 26

Baseline

Question 27

can help match ventilation and perfusion through the redistribution of oxygen and blood flow in the lungs, which improves gas exchange.
Place least damaged portion of the lungs into a dependent position. The least damaged portions of the lungs receive preferential blood flow, resulting in less (V/Q) mismatch.
Prone positioning
Rotation therapy

Answer 27

Positioning Therapy

Question 28

therapeutic modality that is used to improve oxygenation in patients with ARDS.
Patients who are unable to tolerate the face-down position are not appropriate candidates for this type of therapy.
Prone positioning is contraindicated in patients with increased intracranial pressure, hemodynamic instability, spinal cord injuries, or abdominal surgery.
Prone positioning is discontinued when the patient no longer demonstrates a response to the position change.
The biggest limitation to prone positioning is the actual mechanics of turning the patient.
Abdomen must be allowed to hang free to facilitate diaphragmatic descent.
Before the patient is turned to the prone position, his or her eyes are lubricated and taped closed, tubes and drains are secured, and the procedure is explained to the patient and family
Complications of the procedure include dislodgment or obstruction of tubes and drains, hemodynamic instability, massive facial edema, pressure injuries, aspiration, and corneal ulcerations.

Answer 28

Prone positioning

Question 29

Kinetic therapy and continuous lateral rotation therapy (CLRT) are two forms
The patient is continuously turned from side to side with a rotation of 40 degrees or greater (kinetic therapy)
Two types of beds can perform this type of therapy: (1) an oscillation bed, in which the mattress inflates and deflates to provide rotation, and (2) a kinetic bed, in which the entire platform of the bed rotates.95
Rotation therapy is thought to improve oxygenation through better matching of ventilation to perfusion and to prevent pulmonary complications associated with bed rest and mechanical ventilation.
Complications of the procedure include dislodgement or obstruction of tubes, drains, and lines; hemodynamic instability; and pressure injuries.
To prevent pressure injuries, the patient is positioned 30 degrees from the surface of the mattress regardless of the degree of rotational turn.

Answer 29

Rotation therapy

Question 30

Bronchodilators and adjuncts
Neuromuscular blocking agents

Answer 30

Pharmacology

Question 31

facilitate removal of secretions and dilate airways are of major benefit in the treatment of pulmonary disorders. Mucolytics are administered to help liquefy mucus secretions, which facilitates their removal. Bronchodilators such as beta2 agonists and anticholinergic agents aid in smooth muscle relaxation and are of particular benefit to patients with airflow limitations. Steroids are often used in conjunction with beta2 agonists to enhance their effects and to decrease airway inflammation.

Answer 31

Bronchodilators and adjuncts

Question 32

Sedation can be used to comfort the patient and to decrease the work of breathing, particularly if the patient is fighting the ventilator.
Neuromuscular paralysis may be necessary to facilitate optimal ventilation. Paralysis also may be necessary because paralytic agents only halt skeletal muscle movement and do not inhibit pain or awareness, they must be administered with a sedative or anxiolytic agent. Pain medication is administered if the patient has a pain-producing illness or surgery. Providing reorientation and explanations for all procedures is crucial, high risk for developing the complications of immobility
Patient safety is another concern because the patient cannot react to the environment.
Peripheral nerve stimulator

Answer 32

Neuromuscular blocking agents

Question 33

Long-term use of neuromuscular blocking agents can result in prolonged neuromuscular blockade and skeletal muscle weakness. To avoid this complication, the patient’s level of paralysis is carefully monitored with the use of a peripheral nerve stimulator (PNS). The PNS delivers an electrical stimulus to a preselected nerve by electrodes, and the response is monitored to gauge the level of paralysis.

Answer 33

Peripheral nerve stimulator