Hiccups (Singultus)
Though usually a benign and self-limited annoyance, hiccups may be persistent and a sign of serious underlying illness. In patients on mechanical ventilation, hiccups can trigger a full respiratory cycle and result in respiratory alkalosis.
Causes of benign, self-limited hiccups include gastric distention (carbonated beverages, air swallowing, overeating), sudden temperature changes (hot then cold liquids, hot then cold shower), alcohol ingestion, and states of heightened emotion (excitement, stress, laughing). There are over 100 causes of recurrent or persistent hiccups, grouped into the following categories:
Central nervous system: Neoplasms, infections, cerebrovascular accident, trauma.
Metabolic: Uremia, hypocapnia (hyperventilation).
Irritation of the vagus or phrenic nerve: (1) Head, neck: Foreign body in ear, goiter, neoplasms. (2) Thorax: Pneumonia, empyema, neoplasms, myocardial infarction, pericarditis, aneurysm, esophageal obstruction, reflux esophagitis. (3) Abdomen: Subphrenic abscess, hepatomegaly, hepatitis, cholecystitis, gastric distention, gastric neoplasm, pancreatitis, or pancreatic malignancy.
Surgical: General anesthesia, postoperative.
Psychogenic and idiopathic.
Clinical Findings
Evaluation of the patient with persistent hiccups should include a detailed neurologic examination, serum creatinine, liver chemistry tests, and a chest radiograph. When the cause remains unclear, CT of the head
