Hyperemesis Gravidarum Flashcards
Definitions
Protracted nausea and vomiting in pregnancy with a triad of:
- > 5% weight loss from pre-pregnancy weight
- Dehydration
- Electrolyte imbalance (i.e. hypoNa, hypoK, ketonuria, raised transaminases etc.)
It is a diagnosis of exclusion
Instead of saying morning sickness, RCOG now uses nausea and vomiting of pregnancy (NVP) with Hyperemesis gravidarum being the extreme form
Aetiology
Epidemiology
- Nausea and vomiting occurs in up to 75% of women in pregnancy
- Nausea and vomiting in pregnancy is more common in urban women than rural women
- Professional working Caucasian women have a decreased incidence compared to women who stay at home
- Hyperemesis gravidarum occurs in 1 in 200 pregnancies
Aetiology
- Unknown
- Various putative mechanisms proposed including an association with high level of serum hCG, oestrogen and thyroxine
- The likely cause is multifactorial
- Causes imbalances of fluid, electrolytes, disturbs nutritional intake and metabolism, causes physical and psychological outcome.
Risk factors:
- Family history of hyperemesis gravidarum
- Previous hyperemesis gravidarum
- Multiple pregnancy or increased placental mass
- Gestational trophoblastic disease
- Triploidy
- Trisomy 21
- Hydrops fetalis
- Associated with: hyperthyroidism, nulliparity, obesity
Symptoms and Signs
Presenting Symptoms
- Presents in 1st trimester
- Morning sickness/ N+V
- Unable to tolerate foods
- Postural dizziness
Signs O/E
- > 5% of weight loss- check and compare to pre-pregnancy
- Dry mucous membranes
- Tachycardia
- Hypotension
- Ketotic breath (suggestive of volume depletion)
- Muscle wasting
DDx
- DKA
- Hyperthyroidism
- PUD
- Hepatitis
- Appendicitis
- Gestational trophoblastic disease
Investigations
RCOG diagnostic criteria to diagnose HG à requires ALL THREE:
- ≥5% pre-pregnancy weight loss
- Dehydration
- Electrolyte imbalance
Examination:
- Basic obs: temperature, pulse, BP, O2 sats, RR, abdomen exam
- Weight
- Signs of dehydration (if severe -> ketonuria and raised urea)
- Signs of muscle wasting
Investigations:
- Body weight
- U&E
- Urine dipstick (check ketones)
- Observations
- If ‘severe’ from PUQE-24 (≥13) à admit
Management
Admission criteria -> IV normal saline with KCl, thiamine (Vitamin B1) supplementation
- Unable to keep down fluids / oral antiemetics
- Ketonuria
- Weight loss >5%
- Co-morbidity (i.e. diabetes) – lower threshold for admission
Mild and moderate NVP/HG treated in the community: Remember VTE, KCl, Vitamin B1 (thiamine)
- > if severe (PUQE ≥13), treat as inpatient
- > if fails, treat as a day case in ambulatory care
PLAN:
1st line: antihistamines
- IV promethazine, cyclizine, prochlorperazine, chlorpromazine
2nd line: antiemetics
- IV ondansetron, metoclopramide (≤5 days), domperidone
- Reassess in 24hrs
- Metoclopramide is 2nd line due to chance for extra-pyramidal symptoms (EPS)
- Ondansetron is 2nd line due to unknown effects in pregnancy
3rd line: steroids
- IV hydrocortisone, BD, 100mg (convert to PO when capable)
4th line: alternative therapy Ginger and P6 wrist acupressure
Combinations can be used if a single medication is ineffective
- Pay attention to the psychological effect of hyperemesis gravidarum
- If admitted (dehydration) -> give VTE prophylaxis (LMWH)
Complications
Maternal (major = VTE, Wernicke’s, hypokalaemia, hyponatraemia)
- Dehydration
- Mallory-Weiss tear
- Wernicke’s encephalopathy (lack of B12) Central pontine myelinolysis (from rapid [Na+] correction)
- Acute tubular necrosis (dehydration)
- VTE (from dehydration)
Foetal:
- IUGR: intrauterine growth retardation
- PTL
- Termination
Prognosis
- May persist throughout pregnancy
- Associated with increased maternal morbidity and mortality
- Can recur in pregnancy- so important to remember what worked well for future
PACES
Nausea and vomiting is a symptom of pregnancy and affects most women to some degree. It begins early in pregnancy, most commonly between the 4th and 7th week. It usually settles by 12–14 weeks, although in some women it may last longer. It is often called ‘morning sickness’ but it can occur at any time of the day or night
If the nausea and vomiting becomes so severe that it leads to dehydration and significant weight loss, it is known as hyperemesis gravidarum.
It may affect 1 to 3 in 100 pregnant women.
This is causing symp very similar to the ones you are experiencing such as…
Women with severe nausea and vomiting or with hyperemesis gravidarum may, however, have a baby with a lower than expected birthweight. So we will continue to monitor the baby’s growth for this reason.
- You will need to be admitted into the hospital and given a drip
- anti-sickness medication and a B vitamin called thiamine; both of these can be given through the drip in your arm if you are unable to keep tablets down
- Cyclizine is the medication that is usually given first. It can be taken in tablet form or by an injection. Prochlorperazine and metoclopramide can be tried if cyclizine has not worked. All three of these medications are considered to be safe in pregnancy.
- special stockings (graduated elastic compression stockings) to help prevent blood clots
Pregnant women are at increased risk of developing
blood clots in their legs, called deep vein thrombosis (DVT) or in their lungs (called pulmonary embolism). Being dehydrated and not being mobile increases this risk further. Heparin injections reduce this risk.
Safety net
- If feel dizzy, LOC, etc –> contact midwife and return to maternity assessment unti
