Respiratory Failure

Definition

A condition in which the respiratory system is unable to provide an adequate amount of oxygen or to remove carbon dioxide efficiently

Normal PaO2: 75-100 mm Hg

Normal PaCO2: 35-45 mm Hg

Hypoxia is a decrease in O2 reaching tissues

Hypercapnia is an increase in CO2 in the blood

Normal pH: 7.35-7.45

Arterial Blood Gas

Measurement of arterial blood gases

Type I Respiratory Failure (hypoxemia)

Type 2 Respiratory Failure (hypercapnia + hypoxemia)

Acute Respiratory Failure

● Trauma● Pulmonary embolism● Overdose● Stroke

Acute Respiratory Distress Syndrome (ARDS)

Respiratory failure characterized by rapid onset of widespread inflammation of the lungs

Symptoms include:

● Shortness of breath● Rapid breathing● Bluish skin coloration

ARDS Pathomechanism

● Diffuse damage to the alveolar-capillary interface● Leakage of protein rich fluid leads to edema and formation of

hyaline membranes in alveoli● Diffuse alveolar damage to type I and II pneumocytes

SPARTAS

Sepsis

Pancreatitis/Pneumonia

Aspiration

uRemia

Trauma

Amniotic fluid embolism

Shock

Neonatal Respiratory Distress System

A lack of surfactant in premature infants causes collapse of alveoli. Underdeveloped type II pneumocytes don’t produce enough surfactant.

Pneumothorax

Collection of air in pleural space between the chest and the lung

Pulmonary Embolism

Embolic blockage of an artery in the lung by an insoluble bolus, typically arising from a DVT

Chronic Respiratory Failure

● Cystic Fibrosis● Neurologic abnormalities● COPD

Cystic Fibrosis

● Defective CFTR gene■ CFTR is involved in the production of

sweat, digestive fluids and mucous

● Fluids that should be thin are thickened

● Thickened lung mucous predisposes to infections

Treatment

● Removal or reversal of causative agent● Ventilatory support

Mrs. Puffer is a 35-year-old single mother, just getting off the night shift. She

reports to the ED in the early morning with shortness of breath. She has cyanosis of

the lips. She has had a productive cough for 2 weeks. Her temperature is 38.9,

blood pressure 110/76, heart rate 108, respirations 32, rapid and shallow. Breath

sounds are diminished in both bases, with coarse rhonchi in the upper lobes. Chest

X-ray indicates bilateral pneumonia.

What values would you expect to see on her ABG?

a. Normal PaCO2, Elevated PaO2

b. Decreased PaCO2, Decreased PaO2

c. Elevated PaCO2, Normal PaO2