Respiratory Failure/ARDS – 20 Flashcards
ARDS – PaO2/FIO2 ratio
</= 200
Sudden, progressive ARF in which Alveolar cap. membrane damaged –>more permeable to intravascular fluid–>Alveoli fill with fluid
ARDS
Injury or exudative phase
Time Period
1-7 days after insult
Reparative or proliferative phase
Time Period
1-2 wks after initial lung injury
Fibrotic or chronic/late phase
Time Period
2-3 wks after initial lung injury
Neutrophils adhere to plum microcirculation–> damage to vascular endothelium & increased cap perm–>Engorgement of peribronchial & perivascular interstitial space–>Intrapulm. shunt develops –>alveoli fill w/ fluid & bld passing through cannot be oxygenated; Alveolar cells (I & II) damaged–>Surfactant dysfunx & atelectasis–>Hyaline membranes line alveoli. Severe V/Q mismatch & shunting of pulmonary cap blood–>hypoxemia
(Unresponsive to increasing O2 concentrations)–>Lungs become less compliant
1-7 days after insult
Injury or exudative phase
Influx of neutrophils, monocytes, and lymphocytes–>Fibroblast proliferation. Lung becomes dense and fibrous, compliance continues to decrease. Hypoxemia worsens.
reparative phase persists
1-2 wks after initial lung injury
If reparative phase persists
widespread fibrosis results
If phase is arrested, lesions resolve
Lung completely remodeled (sparsely collagenous & fibrous tissues); Requires long-term mechanical ventilation; Survival chances poor
2-3 wks after initial lung injury
Fibrotic or chronic/late phase
Survival chances poor
dyspnea tachypnea cough restlessness Auscultation normal-fine, scattered crackles
ARDS- Initial presentation
Chest Xray ARDS
normal or scattered interstitial infiltrates initially
Evident discomfort
↑WOB
Intercostal & suprasternal retractions
Pulmonary funX tests –> decreased compliance & lung vol.
ARDS-increased fluid accumulation and decreased compliance
Chest x-ray–>whiteout/ white lung
d/t consolidation and coalescing infiltrates widespread throughout lungs
Rupture of overdistended alveoli during mechanical ventilation
Barotrauma
smaller tidal volumes results in
higher PaCO2
Permissive hypercapnia
Keep pH >/= 7.2
Decreased risk of Baro & Volutrauma
Occurs when large tidal volumes used to ventilate noncompliant lungs–>Alveolar fx/tears and mvmnt of fluids & proteins into alveolar spaces
Volutrauma
NDx ARDs
Ineffective airway clearance Ineffective breathing pattern Risk for imbalanced fluid volume Anxiety Impaired gas exchange Imbalanced nutrition: less than body requirements
Overall goals for patient with ARDS
PaO2 >/= 60 mmHg
Adequate lung ventilation to maintain normal pH
Goals for patient recovering from ARDS
PaO2 normal for age/baseline with FIO2 21%
SaO2 >/= 90%
Patent airway/ Clear lungs
Oxygen administration
Give lowest concentration that –> PaO2 60 mmHg+
ScvO2 = 60% to 80%
SpO2 continuously monitored > 90%
When FIO2 exceeds 60% for more than 48 hours–>
Risk for 02 tox
Additional pressures from PEEP can
compromise venous return to R side of the heart–>Decreased preload, CO, and BP
PEEP @ 5cm H20 compensates for
loss of glottic function
Prior to initiation of Vibratory pack for chest PT
Obtain baseline assessment
Anxiety Goal ARDs
Decreased anxiety ( <+2 )
2 Classifications of ARF
Hypoxemic respiratory failure
Hypercapnic respiratory failure
Hypoxemic respiratory failure d/t
Insufficient O2 transferred to the blood
Hypercapnic respiratory failure d/t
Inadequate CO2 removal
ARF
PaO2 of 60 mm Hg or less
Inspired [O2] of 60%+
Hypoxemic Respiratory Failure
ARF
PaCO2 above norm (>45 mm Hg)
(pH <7.35)
Hypercapnic Respiratory Failure
