CHEST INJURIES - Medicine for Mountaineering and Other Wilderness Activities - page 117

Ablowtothelowerchestmayalsodamageintraabdominalorgans—theliveriftheblow
has been low on the right side, the spleen by left-sided injuries, or the kidneys by a blow to
the back ( Chapter 10: Abdominal Injuries ) .
Pneumothorax
Pneumothorax allows the lung to partially or totally collapse ( Figs. 9-2 and 9-3 ) . When
the air is introduced by rupture of a small bleb or air bubble on the surface of the lung,
the pneumothorax is considered “spontaneous.” If the air is introduced by an injury, the
pneumothorax is “traumatic.” Occasionally a tear in the surface of the lung functions as a
one-way valve, allowing air to enter the pleural space during inspiration but closing and
not allowing air to escape during expiration. As a result the lung collapses, tension within
thepleuralspaceincreaseswitheverybreath,andbothrespiratoryandcardiacfunctioncan
be severely impaired. This condition is called tension pneumothorax.
Figure 9-2. Pulmonary function with a punctured lung and intact chest wall 1
Figure 9-3. Collapse of the left lung and shift of heart and trachea to the right with left pneumothorax
A spontaneous pneumothorax is heralded by the sudden onset of chest pain associated
withshortnessofbreath.Suchalarmingsymptomsinanolderpersonandontheleftsideof
the chest may suggest a heart attack. Spontaneous pneumothorax is rarely fatal, but can be
painful and usually compromises respiratory capacity. Individuals with spontaneous pneu-
mothorax should be evacuated promptly. If shortness of breath is not severe, they may be
able to walk out unassisted.
A key to the diagnosis of pneumothorax is the absence of audible breath sounds when
listeningtothechest,preferablywithastethoscope.Withatensionpneumothoraxresulting