Page 114 - Critical Care Notes

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RESP
■ Administer O 2 via mask or mechanical ventilation.
■ Assess oxygenation: ABGs, pulse oximetry (SpO 2 ), capnography. Consider
bicarbonate if acidosis present.
■ Administer bronchodilators: terbutaline (Brethaire, Bricanyl), albuterol
(Proventil), ipratropium bromide (Atrovent HFA).
■ Administer corticosteroids: methylprednisolone (Solu-Medrol).
■ Obtain blood cultures.
■ Administer antibiotics if infection suspected.
■ Administer analgesics for pain as indicated.
■ Administer nitrates: nitroglycerin or nitroprusside (Nitropress), inotropes
(dopamine, dobutamine, norepinephrine), and vasopressors as indicated to
provide hemodynamic support.
■ Provide enteral or parenteral nutritional support.
■ Administer diuretics: furosemide (Lasix) or metolazone (Zaroxolyn) if
refractory to Lasix.
■ Consider extracorporeal membrane oxygenation (ECMO).
■ Assess for complications related to mechanical ventilation (refer to
Basics tab).
Acute Respiratory Distress Syndrome (ARDS)
ARDS is defined as noncardiogenic pulmonary edema characterized by severe
refractory hypoxemic respiratory failure and decreased pulmonary compliance
quickly leading to acute respiratory failure.
Pathophysiology
↑ capillary/alveolar membrane permeability → interstitial and alveolar leak →
right-to-left intrapulmonary shunting → severe and refractory hypoxemia, meta-
bolic acidosis. Inactivation of surfactant → alveolar atelectasis and collapse,
↑ alveolar dead space, ↓ lung compliance, → hypoventilation and hypercapnia
with severe hypoxemia.
· ·
The intrapulmonary shunt is a type of V/Q mismatch because a percentage
of cardiac output is not oxygenated as a result of collapsed or fluid-filled and
nonventilated alveoli (physiological shunt), there is an absence of blood flow to
already ventilated alveoli (alveoli dead space), or combination of both (refer to
· ·
section on V/Q Mismatch). In ARDS, this shunt is ≥15%.
Clinical Presentation
Symptoms of ARDS occur within 24 to 48 hr of cause and include:
■ Increased respiratory rate, increased work of breathing, dyspnea, cyanosis
■ Crackles, rhonchi or wheezes, dry cough
■ Intercostal and suprasternal retraction, retrosternal discomfort
■ Agitation, restlessness, apprehension, anxiety, confusion
■ Diaphoresis
■ Abdominal paradox
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