Involvement of the autonomic nervous system occurs several days after the onset of spasms, and causes:
Sudden cardiac death is now the most frequent cause of mortality in tetanus in ventilated patients. [8]
Abdominal pain and rigidity may mimic an acute abdomen. Constipation, diarrhoea, and ileus may also occur.
Pharyngeal and laryngeal spasm may cause airway obstruction. The combination of poor swallow, increased saliva, inadequate cough and raised intra-abdominal pressure increases risk of aspiration. Pneumonia is common.