hyperemesis_gravidarum
hyperemesis gravidarum
Introduction
Differential diagnosis of persistent vomiting in pregnancy
relatively common causes
hyperemesis gravidarum
gastroenteritis - in particular, suspect this if diarrhoea is present as well
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less common causes
unusual causes
ED Mx of hyperemesis
dehydrated or ketonuric
IV thiamine supplementation to prevent the complication of Wernicke’s encephalopathy should be administered to all women with hyperemesis gravidarum severe enough to warrant admission. Thiamine dose is 100mg daily for 2-3 days. This will normally need to be given parenterally, 100mg thiamine in 100mL 0.9% sodium chloride IV over 30-60 minutes.
consider VTE prophylaxis if requiring admission
these patients usually do well with iv rehydration Rx (eg. N Saline 1L over 2hrs then 1L over 2-4hrs then 3L/day of Hartmann's with 5% glucose - do not use 5% glucose alone!) + anti-emetics (see below)
often these patients can be directly admitted from triage to a ED short stay observation unit using a care plan pathway
send bloods for FBE, U&E, and, TSH if thyroid testing has not been done
check urinalysis and send MSU m/c/s if suspicious of UTI
exclude other conditions such as a surgical abdomen
ensure an USS has be done or will be done within a week or so to exclude multiple pregnancies and molar pregnancy.
repeated vomiting usually causes some oesophagitis and may even cause Mallory-Weiss tear resulting in small amounts of blood in vomit.
not significantly dehydrated and not ketonuric
these patients can usually be managed as an outpatient
check urine, USS as above
non-pharmacologic measures
small frequent meals and snacks aiming for food/fluid every 1-2 hours
avoid foods that may trigger symptoms including spicy, odourous, very sweet or acidic foods
chew foods slowly
eliminate other non-dietary triggers
during the first trimester avoid multivitamins that contain high levels of iron (>27mg iron per tablet), re-start after 12wks
adequate sleep
sea-sickness P6 acupressure wristbands
ginger (orally as a tablet or syrup) to a maximum of 1g daily
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oral agents to consider (as per WH guideline 2019):
first line:
pyridoxine (vitamin B6) 25mg o tds (this medication is optional as effectiveness is limited)
second line:
add
doxylamine (Restavit, a H1 antagonist) 12.5mg o nocte, increase to 25mg nocte, then add 12.5mg mane and afternoon if needed
third line, add either ONE of the following:
fourth line, add a sedating antihistamine:
fifth line if severe, persistent or resistant vomiting:
ondansetron (Zofran) 4-8mg o (tablet or wafer) bd/tds max 24mg/day
sixth line - consider parenteral administration of ONE of the following:
seventh line:
prednisolone 50mg o daily for 3 days, then 25mg o daily for 3 days, then reduce by 5mg as tolerated
don't forget to remind patient to take folate supplements as well to reduce probability of neural tube defects
patients with > 10% LOW with persistent symptoms or a pre-pregnancy BMI < 18 should be referred to dietitian
hyperemesis_gravidarum.txt · Last modified: 2019/08/18 13:09 (external edit)