Page 113 - Critical Care Notes

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Respiratory Disorders
Respiratory Failure
Respiratory failure occurs when there is either insufficient oxygenation
and/or inadequate CO 2 elimination. Broadly defined as PaO 2 <50 mm Hg or
PaCO 2 >50 mm Hg and arterial pH <7.35 when baseline ABGs are considered
normal. The PaCO 2 /FIO 2 ratio is generally <200. Respiratory failure generally
classified as either hypoxemic (type I, PaO 2 <60 mm Hg or low PaCO 2 ) or
hypercapnic (type II, PaCO 2 >50 mm Hg). May also be classified as acute or
chronic.
Clinical Presentation
■ Tachypnea, dyspnea
■ Diminished breath sounds, wheezing and rhonchi, crackles
■ Use of accessory muscles to breathe
■ Tachycardia and cardiac arrhythmias
■ Cold, clammy skin, diaphoresis
■ Ashen skin
■ Peripheral cyanosis of skin, oral mucosa, lips, and nailbeds
■ Sitting bolt upright or slightly hunched over
■ Asterixis if severe hypercapnia
■ Agitation, anxiety
■ Restlessness, lethargy, altered mental status (confused, disoriented),
somnolence
■ Seizures, coma
■ Can lead to sepsis and ventilator-associated pneumonia after intubation
Diagnostic Tests
■ ABGs
■ CXR and sputum cultures
■ Pulmonary function tests
■ CBC especially WBC, Hgb, and Hct
■ ECG, echocardiogram may be helpful
■ CT scan
· ·
■ V/Q scan
■ Angiography
■ Toxicology screen
■ Serum chemistry tests
Management
■ Treat underlying cause.
■ Monitor VS, heart rhythm, fluid and electrolyte balance, intake and output.
■ Assess cardiac, respiratory, and neurological status.
RESP