Nausea and Vomiting

Essentials

• The most common cause of acute nausea is an acute gastroenteritis. The patient usually has concurrent watery diarrhoea, abdominal cramps and fever. Similar illness is possibly found in close contacts of the patient.
• Nausea may be caused by a condition needing urgent treatment: myocardial infarction, hypoglycaemia, ketoacidosis, pancreatitis, gastrointestinal obstruction, appendicitis, meningitis or other severe infection (pneumonia, sepsis), increased intracranial pressure, acute cerebrovascular disorder or intoxication.
• Other causes of nause include e.g. epilepsy, pregnancy, radiotherapy, medications (e.g. many antimicrobials, opioids, cytostatic drugs), hepatitis (e.g. hepatitis A), thyrotoxicosis, otogenic causes and gastritis.
• Fairly common causes of prolonged or recurrent nausea encountered in outpatient care include migraine and episodes of bulimia, stress and various mental disorders.

Diagnostic approach in nausea

Diagnostic clues

• See table T1.

Aetiological clues from patient history

• Sudden vomiting without preceding nausea may be associated with increased intracranial pressure.
• Dehydration and weight loss suggest an organic disease.
• Morning nausea and vomiting are typical of early pregnancy, alcoholic gastritis, increased intracranial pressure, and uraemia.
• Vomiting after a meal suggests pyloric obstruction (gastric or duodenal ulcer, carcinoma), hepatic or biliary problems or a psychogenic cause (bulimia).
• Voluminous, bile-stained vomiting suggests proximal intestinal obstruction.
• Haematemesis suggests bleeding ulcer, acute gastric mucosal damage, Mallory-Weiss ulceration, or oesophageal varices.
• Faecal vomitus is caused by distal intestinal obstruction.
• History of travelling. Initial symptoms of acute hepatitis often include food aversion and nausea. Nausea and vomiting may be the cardinal symptoms of giardiasis.
• Lactose intolerance may sometimes present as nausea and vomiting without evident intestinal symptoms.
• The patient's medication may be cause (nitrofurantoin, sulphasalazine, imidazoles, erythromycin, tetracycline, metformin, tramadol, other opioids, antidementia drugs, SSRI drugs, digoxin in toxic concentrations).
• If the general condition remains unaffected the symptoms may be of psychogenic origin.

Investigations

• Consider first whether a referral to a hospital is indicated Acute Abdomen in the Adult.
• If the patient is not referred to hospital the following tests are performed according to the history and clinical signs:
  • CRP, plasma glucose, pancreatic plasma amylase concentration, ECG, and, particularly in the elderly, a urine test.
• In prolonged symptoms (in addition to the former)
  • Basic blood count with platelet count, plasma creatinine, potassium, sodium, ALT, alkaline phosphatase, TSH, drug concentrations, e.g. serum digoxin

Further investigations

• If intestinal obstruction Intestinal Obstruction, Paralytic Ileus and Pseudo-Obstruction is suspected (vomiting, pain, bloating, high-pitched bowel sounds), the first-line examination is abdominal CT scan. Its availability in hospital emergency departments is good (check local availability).
• In special circumstances (e.g. recurring intestinal obstruction whose cause is known), plain radiograph of the abdomen may be considered if not transferring the patient to a hospital is preferred.

Drug therapy of nausea Acupuncture for Postoperative Nausea and Vomiting, Drugs for the Treatment of Nausea and Vomiting in Adults in the Emergency Department Setting