Acute Respiratory Failure
objective
By the end of this lesson the learner is expected to:
1. Identify the Definition respiratory failure .
2.Describe the Pathophysiology respiratory failure .
3.Discuss the Clinical Manifestations respiratory failure.
4.Discuss the management respiratory failure.
5. Discuss the Nursing Diagnosis respiratory failure
Definition
Acute respiratory failure (ARF) is defined as a fall in arterial oxygen tension (PaO2) to less than 50 mm Hg (hypoxemia) and a rise in arterial carbon dioxide tension (PaCO2) to greater than 50 mm Hg
(hypercapnia), with an arterial pH of less than 7.35.
Pathophysiology
Acute respiratory failure is diagnosed when the patient is unable to maintain adequate blood gas values.
Hypoxemia may result from inadequate ventilation (air movement in and out of lungs) or poor oxygenation (adequate
ventilation but inability to get the oxygen into the blood and therefore the cells) or both
Respiratory system mechanisms leading to ARF include:
• Alveolar hypoventilation
• Diffusion abnormalities
• Ventilation–perfusion mismatching
Causes
Common causes of ARF can be classified into four categories:
Decreased respiratory drive.
Dysfunction of the chest wall.
Dysfunction of the lung parenchyma.
Other causes.
Decreased Respiratory Drive:
Severe head injury .
Large brain stem lesions .
Sedative drugs .
Metabolic ( hypothyroidism ).
These disorders impair the normal response of chemoreceptors in the brain to normal
respiratory stimulation.
Dysfunction Of The Chest Wall:
These include musculoskeletal disorders (muscular dystrophy, polymyositis),
neuromuscular junction disorders
(myasthenia gravis, poliomyelitis), some peripheral nerve disorders, and spinal cord disorders (amyotrophic lateral
sclerosis, Guillain-Barré syndrome, and cervical spinal cord injuries).
Dysfunction Of Lung Parenchyma:
Pleural effusion, hemothorax, pneumothorax, and upper airway obstruction are conditions that interfere with ventilation by preventing expansion of the lung.
Other diseases and conditions of the lung that lead to ARF include pneumonia, status
asthmaticus, atelectasis, pulmonary embolism, and pulmonary edema.
Other Causes :
Include major abdominal & thoracic surgery .
Due to effect of anesthesia ,analgesia ,sedatives & pain .
Clinical Manifestations
Early signs are those associated with impaired oxygenation and may include:-
restlessness.
fatigue.
Headache.
Dyspnea.
air hunger.
Tachycardia.
and increased blood pressure.
.
As the hypoxemia progresses, more
obvious signs may be present including :- Confusion.
Tachycardia.
Tachypnea.
central cyanosis.
and finally respiratory arrest.
Clinical Manifestations
Physical findings are those of acute respiratory distress, including
use of accessory muscles.
decreased breath sounds if the patient cannot adequately ventilate.
and other findings related specifically to the underlying disease process and cause of ARF.
Diagnostic Tests
Respiratory failure is diagnosed when
PaO2 falls below 60 mm Hg or PaCO2 is elevated above 50 mm Hg.
Some patients with chronic respiratory disease have adapted to impaired gas exchange. In these patients a drop in PaO2 of 10 to 15 mm Hg is considered acute failure.
chest x-ray examinations may be used to determine the cause and guide treatment.
Pulse oximetry is used to continuously monitor oxygen saturation
Medical Management
The objectives of treatment are to correct the underlying cause and to:
restore adequate gas exchange in the lung.
Intubation and mechanical ventilation may be required to maintain adequate ventilation and oxygenation while the underlying cause is corrected.
Nursing Management
Nursing management of the patient with ARF includes assisting with intubation and
maintaining mechanical ventilation . The nurse assesses the patient’s respiratory status by
monitoring the patient’s level of response,
arterial blood gases, pulse oximetry, and vital signs and assessing the respiratory system. The nurse implements strategies (eg, turning
schedule, mouth care, skin care, range of motion of extremities) to prevent
complications.
Nursing Management
The nurse also assesses the patient’s
understanding of the management strategies that are used and initiates some form of
communication to enable the patient to express his or her needs to the health care team.
Management of Patients With Chest and
Lower Respiratory Tract Disorders that led to ARF.
As the patient’s status improves, the nurse assesses the patient’s knowledge of the
underlying disorder and provides teaching as appropriate to address the underlying disorder.
Nursing Diagnosis
1- Impaired gas exchange related to decreased ventilation
Expected Outcomes The patient will experience improved gas exchange, Interventions
Assess lung sounds, respiratory rate and effort, use of accessory muscles.
Observe skin and mucous membranes for cyanosis.
Assess degree of dyspnea on ascale of 0 to 10, 0 no dyspnea,10 worst dyspnea.
Monitor for confusion or changes in mental status
Monitor arterial blood gas values and pulse oximetry as ordered
Elevate head of bed or help patient to lean on over bed table.
Position with good lung dependent (“good lung down”).
Administer supplemental oxygen at 2 L/min unless ordered otherwise.
Place a fan in the patient’s room.
2-Ineffective airway clearance related to excessive secretions
Expected Outcomes The patient will have improved airway clearance
Interventions
Assess lung sounds q4th and prn.
Monitor amount, color, and consistency of sputum
Turn patient q2h or encourage to ambulate if able.
Encourage patient to cough and deep breathe every hour and prn.
Administer expectorants as ordered.
If patient is unable to cough up
secretions, suction per institution policy.
Obtain order for chest physiotherapy or flutter valve if indicated
3-Ineffective breathing pattern related to anxiety or pain
Expected Outcomes The patient will
maintain an effective breathing pattern
Interventions
Assess respiratory rate, depth, and effort q4h and prn.
Monitor blood gas and oxygen saturation values.
Determine and treat the cause of ineffective breathing pattern.
Place patient in Fowler’s or semi-Fowler’s position.
Teach patient to use diaphragmatic breathing, with a regular 2second in, 4 second out pattern
4-Activity intolerance related to imbalance between oxygen supply and demand
Expected Outcomes :Patient will receive assistance with self-care until he or she is able to carry out own ADLs.
Interventions
Assess amount of activity the patient can tolerate without becoming short of
breath.
Monitor vital signs and oxygen saturation with activities.
Allow uninterrupted rest at night as much as possible.
Slowly increase activity as able.
Allow patient to rest between activities.
Bed rest may be necessary during acute dyspnea.
Obtain bedside commode, shower chair, handheld showerhead,
if needed.
Obtain portable oxygen if patient is able to ambulate
Evaluation
If interventions have been effective, the patient will state that dyspnea is
controlled.
Mental status will be normal for the patient.
Airways will be kept clear at all times, and the patient’s respiratory rate will be regular and within normal limits.
