NU 456 - Exam 3
Practice Questions &
Answers
Comprehensive Explanations
& Rationales
Key Concepts • Review
Questions • Exam Preparation
,What is Acute Respiratory Failure? -Results from inadequate gas exchange on room air
-PaO2 < 60 mmHg
-PaCO2 > 50 mmHg
-pH ≤ 7.30
Etiology of Acute Respiratory Failure -Failure of oxygenation
•Insufficient O2 transferred to the blood (Hypoxemic)
-Failure of ventilation
•Inadequate CO2 removal (Hypercapnic)
-Both of the above
Hypoxemic -Oxygen failure
-PaO2 ≤ 60 mmHg on 60% oxygen
-Acute (min to hours)
-Chronic (several days or longer)
Hypercapnic -Ventilatory failure
-PaCO2 > 45 mmHg and pH <7.35
-Acute (min to hours)
-Chronic (several days or longer)
Hypoxemic respiratory failure Failure of oxygenation
-Insufficient O2 transferred to the blood
Hypercapnic respiratory failure Failure of Ventilation
-Inadequate CO2 removal
-Imbalance between ventilatory supply and demand
•Asthma
•Emphysema
•Chronic Bronchitis
•Cystic Fibrosis
-CO2 levels cannot be maintained w/in normal limits due to
•Increase in CO2 production
•Decrease in alveolar ventilation
Consequences of hypoxemia & hypoxia -Metabolic acidosis & cell death
•aerobic & anaerobic metabolism
-Decreased cardiac output
-Impaired renal function
-GI tissue ischemia
Clinical Manifestations of Respiratory Failure -Rapid, shallow breathing pattern
-Dyspnea
-Tripod position
-Pursed lip breathing
-Retractions
-Paradoxical breathing
-Diaphoresis
-Crackles in lungs
-Absent or diminished breath sounds
-Bronchial breath sounds
-Pleural friction rub
Diagnostic studies for Respiratory Failure -History & Physical assessment
-Chest x-ray
-ABG analysis
-CBC
-Sputum/blood cultures
-Electrolytes
-ECG
-Urinalysis
-CT scan
-V/Q lung scan
-Pulmonary artery catheter (severe)
,Compensatory mechanisms for respiratory failure -Tripod positioning
-Pursed lip breathing
-Retraction
-Paradoxical breathing
-Augmented cough
-Huff coughing
-Staged Cough
**
Nursing Diagnosis for Respiratory Failure -Ineffective gas exchange
-Ineffective airway clearance
-Ineffective breathing pattern
-Risk for fluid volume imbalance
-Altered nutrition
-Risk for impaired skin integrity
-Anxiety
Respiratory therapy for Respiratory Failure Oxygen Therapy
-Tolerated by patient
-Maintain PaO2 >60 mmHg
-Maintain SaO2 >90%
-At lowest O2 concentration possible
Mobilize Secretions
-Effective coughing
-Adequate hydration & humidification
-Chest physiotherapy
-Airway suctioning
-Patient positioning/ambulation
Hydration & Humidification
-Adequate fluid intake
-IV hydration
-Humidification devices
-O2 via aerosol
-Mucolytic drugs
Chest Physiotherapy
-Postural drainage
-Percussion
-Vibration
Types of airway suctioning -Nasopharyngeal
-Oropharyngeal
-Nasotracheal
Positive pressure ventilation (PPV) -Used most commonly in acute respiratory failure
-Causes: increased intrathoracic pressure
-Leads to: reduced venous return, ventricular preload & cardiac output, which
results in hypotension
-Effect is greater in presence of hypovolemia
Noninvasive PPV BiPAP and CPAP
Drug therapy for Respiratory Failure Bronchodilators
-Relief of bronchospasm
Reduction of airway inflammation
-Corticosteroids
Reduction of pulmonary congestion
-Diuretics
-Nitrates if heart failure present
Treatment of pulmonary infections
-IV antibiotics
Reduction of severe anxiety, pain, and agitation
-Benzodiazepines
-Opioids
, Supportive therapy for Respiratory Failure -Maintain adequate CO & hemoglobin concentrations
•Transfusions
-Therapeutic paralysis
-Nutritional support
-Hemodynamic monitoring
Huff Coughing vs Staged Coughing Huff Coughing
-Series of coughs performed while saying "huff"
-Effective in clearing central airways
Staged Coughing
-Sit leaning forward
-Take three deep breaths through mouth and cough
Pursed Lip Breathing Increases SaO2 by slowing respirations, allowing more time for expiration and
preventing small bronchioles from collapsing
Retraction Inward movement of intercostal spaces or supraclavicular area and use of
accessory muscles during inspiration or expiration
Paradoxical Breathing The abdomen rises and the chest is pulled inward during inspiration. On expiration
the abdomen falls and the chest expands
Tripod Positioning Decreases work of breathing by increasing the anteroposterior diameter of the chest
and changing the pressure in the thorax
Phase I of ARDS Injury & Exudative
-1-7 days after injury
-pH: 7.49 alkalosis
-PaCO2: 34 alkalosis
-PaO2: 90 normal
-Base Excess: +3 alkalosis
-Physiologic Shunt: >5%
-Respiratory Rate: 18-20
-Tidal volume: slight increase
-Assessable symptoms:
•Tachypnea & Hypoventilation
Phase II of ARDS Reparative
-1 week after injury
-pH: 7.50 alkalosis
-PaCO2: 30 alkalosis
-PaO2: 60 Hypoxemia
-Base Excess: +1 Normal
-Physiologic Shunt: >10%
-Respiratory rate: >20
-Tidal volume: Moderate increase
-Assessable symptoms:
•Dyspnea/Tachypnea
•Hyperventilation
•Retractions
•Fatigue
•Fine Crackles
•Agitation/Restlessness
Practice Questions &
Answers
Comprehensive Explanations
& Rationales
Key Concepts • Review
Questions • Exam Preparation
,What is Acute Respiratory Failure? -Results from inadequate gas exchange on room air
-PaO2 < 60 mmHg
-PaCO2 > 50 mmHg
-pH ≤ 7.30
Etiology of Acute Respiratory Failure -Failure of oxygenation
•Insufficient O2 transferred to the blood (Hypoxemic)
-Failure of ventilation
•Inadequate CO2 removal (Hypercapnic)
-Both of the above
Hypoxemic -Oxygen failure
-PaO2 ≤ 60 mmHg on 60% oxygen
-Acute (min to hours)
-Chronic (several days or longer)
Hypercapnic -Ventilatory failure
-PaCO2 > 45 mmHg and pH <7.35
-Acute (min to hours)
-Chronic (several days or longer)
Hypoxemic respiratory failure Failure of oxygenation
-Insufficient O2 transferred to the blood
Hypercapnic respiratory failure Failure of Ventilation
-Inadequate CO2 removal
-Imbalance between ventilatory supply and demand
•Asthma
•Emphysema
•Chronic Bronchitis
•Cystic Fibrosis
-CO2 levels cannot be maintained w/in normal limits due to
•Increase in CO2 production
•Decrease in alveolar ventilation
Consequences of hypoxemia & hypoxia -Metabolic acidosis & cell death
•aerobic & anaerobic metabolism
-Decreased cardiac output
-Impaired renal function
-GI tissue ischemia
Clinical Manifestations of Respiratory Failure -Rapid, shallow breathing pattern
-Dyspnea
-Tripod position
-Pursed lip breathing
-Retractions
-Paradoxical breathing
-Diaphoresis
-Crackles in lungs
-Absent or diminished breath sounds
-Bronchial breath sounds
-Pleural friction rub
Diagnostic studies for Respiratory Failure -History & Physical assessment
-Chest x-ray
-ABG analysis
-CBC
-Sputum/blood cultures
-Electrolytes
-ECG
-Urinalysis
-CT scan
-V/Q lung scan
-Pulmonary artery catheter (severe)
,Compensatory mechanisms for respiratory failure -Tripod positioning
-Pursed lip breathing
-Retraction
-Paradoxical breathing
-Augmented cough
-Huff coughing
-Staged Cough
**
Nursing Diagnosis for Respiratory Failure -Ineffective gas exchange
-Ineffective airway clearance
-Ineffective breathing pattern
-Risk for fluid volume imbalance
-Altered nutrition
-Risk for impaired skin integrity
-Anxiety
Respiratory therapy for Respiratory Failure Oxygen Therapy
-Tolerated by patient
-Maintain PaO2 >60 mmHg
-Maintain SaO2 >90%
-At lowest O2 concentration possible
Mobilize Secretions
-Effective coughing
-Adequate hydration & humidification
-Chest physiotherapy
-Airway suctioning
-Patient positioning/ambulation
Hydration & Humidification
-Adequate fluid intake
-IV hydration
-Humidification devices
-O2 via aerosol
-Mucolytic drugs
Chest Physiotherapy
-Postural drainage
-Percussion
-Vibration
Types of airway suctioning -Nasopharyngeal
-Oropharyngeal
-Nasotracheal
Positive pressure ventilation (PPV) -Used most commonly in acute respiratory failure
-Causes: increased intrathoracic pressure
-Leads to: reduced venous return, ventricular preload & cardiac output, which
results in hypotension
-Effect is greater in presence of hypovolemia
Noninvasive PPV BiPAP and CPAP
Drug therapy for Respiratory Failure Bronchodilators
-Relief of bronchospasm
Reduction of airway inflammation
-Corticosteroids
Reduction of pulmonary congestion
-Diuretics
-Nitrates if heart failure present
Treatment of pulmonary infections
-IV antibiotics
Reduction of severe anxiety, pain, and agitation
-Benzodiazepines
-Opioids
, Supportive therapy for Respiratory Failure -Maintain adequate CO & hemoglobin concentrations
•Transfusions
-Therapeutic paralysis
-Nutritional support
-Hemodynamic monitoring
Huff Coughing vs Staged Coughing Huff Coughing
-Series of coughs performed while saying "huff"
-Effective in clearing central airways
Staged Coughing
-Sit leaning forward
-Take three deep breaths through mouth and cough
Pursed Lip Breathing Increases SaO2 by slowing respirations, allowing more time for expiration and
preventing small bronchioles from collapsing
Retraction Inward movement of intercostal spaces or supraclavicular area and use of
accessory muscles during inspiration or expiration
Paradoxical Breathing The abdomen rises and the chest is pulled inward during inspiration. On expiration
the abdomen falls and the chest expands
Tripod Positioning Decreases work of breathing by increasing the anteroposterior diameter of the chest
and changing the pressure in the thorax
Phase I of ARDS Injury & Exudative
-1-7 days after injury
-pH: 7.49 alkalosis
-PaCO2: 34 alkalosis
-PaO2: 90 normal
-Base Excess: +3 alkalosis
-Physiologic Shunt: >5%
-Respiratory Rate: 18-20
-Tidal volume: slight increase
-Assessable symptoms:
•Tachypnea & Hypoventilation
Phase II of ARDS Reparative
-1 week after injury
-pH: 7.50 alkalosis
-PaCO2: 30 alkalosis
-PaO2: 60 Hypoxemia
-Base Excess: +1 Normal
-Physiologic Shunt: >10%
-Respiratory rate: >20
-Tidal volume: Moderate increase
-Assessable symptoms:
•Dyspnea/Tachypnea
•Hyperventilation
•Retractions
•Fatigue
•Fine Crackles
•Agitation/Restlessness
