Nausea and vomiting

Question 1

What’s in the vomit?

Answer 1

Reports of coffee grounds may indicate upper GI bleeding but represent one of the most over-called signs in clinical medicine- always verify yourself and look for other evidence of GI bleeding.
Recognisable food = gastric stasis.
Feculent = small bowel obstruction.

Question 2

Timing of vomiting

Answer 2

Morning = pregnancy or raised ICP.
1h post food = gastric stasis/ gastroparesis (DM).
Vomiting that relieves pain = peptic ulcer.
Preceded by loud gurgling = GI obstruction.

Question 3

Tests to investigate vomiting

Answer 3

Bloods: FBC, U&E, LFT, Ca2+, glucose, amylase.
ABG: A metabolic (hypochloraemic) alkalosis from loss of gastric contents (pH >7.45, raised HCO3-) indicates severe vomiting.
Plain AXR: If suspected bowel obstruction.
Upper GI endoscopy: If suspicion of bleed or persistent vomiting.
Consider head CT in case of raised ICP.

Question 4

Treatment of vomiting

Answer 4

Identify and treat underlying causes.
Symptomatic relief: anti-emetics.
Be pre-emptive, e.g. pre-op for post-op symptoms.
Try oral route first.
30% need a 2nd line anti-emetic, so be prepared to prescribe more than one.
Give IV fluids with K+ replacement if severely dehydrated or nil by mouth, and monitor electrolytes and fluid balance.