Page 35 - Critical Care Nursing Demystified

20 CRITICAL CARE NURSING DeMYSTIFIED

KEY WORDS

ABGs – arterial blood gases Lung compliance
AC – assist-controlled ventilation LWP – Lateral wall pressure
ALI – acute lung injury Minimal leak technique
ARDS – adult respiratory distress Mucus plug
syndrome MV – mechanical ventilation
ARF – acute respiratory failure PEEP – positive end-expiratory
Aspiration pressure
Atelectasis Pleural effusion
BiPAP – bilevel positive airway Pneumothorax
pressure PPV – Positive pressure ventilation
BVM – bag-valve mask (manual Pressure support
resuscitator) RT – respiratory therapy
COPD – chronic obstructive SaO – pulse oximetry
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pulmonary disease SIMV – synchronized intermittent
CPAP – continuous positive airway mandatory ventilation
pressure Surfactant
CV – controlled ventilation Tension pneumothorax
ETT – Endotracheal tube V – tidal volume Downloaded by [ Faculty of Nursing, Chiangmai University 5.62.158.117] at [07/18/16]. Copyright © McGraw-Hill Global Education Holdings, LLC. Not to be redistributed or modified in any way without permission.
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FiO – fraction of inspired oxygen Work of breathing
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Anatomy and Physiology

In order to assist the patient with complex respiratory issues, an understanding
of the intricacies of normal breathing and lung compliance patterns is required.
The work of breathing is defined as the amount of force needed to overcome
the elastic and resistive properties of the lungs. Lung compliance refers to the
degree of elasticity or expandability of the lungs and thorax. Any condition that
impedes lung contraction and expansion causes a decrease in compliance.
Increased pressure within the thoracic cavity can interfere with lung expansion.
Examples of certain conditions include emphysema, asthma, pleural effusion,
hemothorax, pneumothorax, empyema, pulmonary edema, pulmonary emboli,
or any other space-occupying lesions within the thoracic cavity.
Such obstructive diseases create a decrease in normal airflow because of dif-
fuse airway narrowing. During normal, quiet ventilation only 2% to 3% of the
total energy expended by the body is required by the pulmonary system. When