Occasionally a child dies in a severe paroxysm from strangulation.
Most deaths are, however, dependent upon complications. Of these
the most frequent is pneumonia, which is not uncommon in infants.
Convulsions also cause many deaths. They may occur during the paroxysms
of coughing and if repeated are very dangerous. The great congestion
of the blood vessels of the head during the paroxysms sometimes leads
to rupture of blood vessels, so, that nose-bleed is not infrequent.
Hemorrhage into the brain may occur. Bleeding beneath the conjunctiva
of the eye-ball results in red blotches over the white of the eye.
These may be small or the blood may spread over the entire white
portion of the eye-ball causing a most striking appearance. Bleeding
into the loose tissues of the eye-lid may occur, producing a “black
eye”. This has been mistaken as due to injury and should be remembered
as something which may occur spontaneously during whooping cough.
In infants disturbances of digestion are frequent, and intestinal
disorders in them are grave and add materially to the danger of the
disease.
After recovery permanent damage to the heart may remain. The condition
brought about by the disease also favors the rapid progress of any
tubercular disease which otherwise might be of little moment.