Hyperemesis Gravidarum

Question 1

What is hyperemesis gravidarum?

Answer 1

Persistent vomiting in pregnancy causing weight loss and ketosis
Weight loss is defined as over 5% of pre-pregnancy weight
May be fatal if no access to help
Thought to be caused by high levels of hCG

Question 2

What are the risk factors for HG?

Answer 2

Previous HG
Multiple pregnancy
Molar pregnancy

Question 3

What is the presentation of hyperemesis gravidarum?

Answer 3

Inability to keep food or fluids down
Weight loss
Nutritional deficiencies
Tachycardia
Postural hypotension
Hypokalaemia and hyponatraemia 
Polyneuritis from low vitamin B
Hypovolaemia
Haematemesis from Mallory-Weiss tears
Renal failure
Liver failure
Inability to swallow saliva (ptyalism) and spitting
Behaviour disorders

Question 4

What are the investigations that need to be conducted for hyperemesis gravidarum?

Answer 4

Urine dip to look for ketones and UTI
FBC may reveal a raised haematocrit
U&Es may reveal electrolyte disturbances like hyponatraemia and hypokalaemia
LFTs - transaminases may be abnormal and albumin low
TFTs if symptoms of hyperthyroidism
US to look for multiple/molar pregnancy

Question 5

When should a patient with HG be admitted to hospital?

Answer 5

When they can’t keep anything down despite oral antiemetics

Question 6

What is the management of patients with HG in hospital?

Answer 6

Aggressive rehydration
Glucose may precipitate Wernicke’s encephalopathy
High dose folic acid and thiamine to prevent Wernicke’s encephalopathy
Give metoclopramide/cyclizine/promethazine
Give ondansetron if these measures fail, but this is not licensed
Daily U&Es to guide sodium and potassium replacement
If vomiting still intractable, try corticosteroids - prednisolone/hydrocortisone IV
These patients are at a high risk of VTE, so give thromboprophylaxis and thromboembolic stockings