Hyperemesis Gravidarum (also known as HG) is a severe type of vomiting of pregnancy which has got deleterious effect on the health of mother and/or incapacitates her in day-to-day activities.
Triad of adverse effects:
- > 5% loss of pre- pregnancy weight
- Dehydration
- Electrolyte imbalance
Incidence:
There has been a marked fall in the incidence during last 30 years (less than 1 in 1,000 pregnancies) because:
- better application of family planning knowledge.
- early visit to antenatal clinic.
- potent antihistaminic and antiemetic drugs.
Etiology:
High risk factors:–
- mostly limited to 1st trimester and resolve by 20 weeks (90%)
- more common in 1st pregnancy,
- Younger age
- Low body mass
- History of motion sickness or migraine
- Family history
- Women suffered nausea and vomiting while on COC’s.
- Unplanned pregnancy, multiple pregnancy, hydatidiform mole.
Theories:
1) Hormonal =
• excess of chorionic gonadotropin or higher biological activity of hcG. • high serum level of oestrogen. • excess of progesterone leading to relaxation of cardiac sphincter of retention of gastric fluids due to impaired gastric motility.
2) Psychogenic = aggravates nausea
3) Dietetic deficiency = low carbohydrate reserve decreases Vit B6, B1.
4) Allergic or immunological basis
5) Decreased gastric motility
Pathology:
Changes in various organs –
- Liver = enzymes are elevated. There is centri-lobular fatty infiltration without necrosis.
- Kidneys = usually normal with fatty change in the cells of first convoluted tubule.
- Heart = small heart, subendocardial haemorrhage
- Brain = small haemorrhage in hypothalamic region
Metabolic, Biochemical & Circulatory changes:
Due to the combined effect of dehydration and starvation due to protracted vomiting
METABOLIC :- For energy supply, fat reserve is broken down.
Fats [due to low carbohydrate] ➡️ Incomplete oxidation ➡️ ketone bodies in blood accumulates ➡️ acetone excreted through kidney and in breath.
BIOCHEMICAL :–
- Loss of water and salt ➡️ decrease in plasma Na, K, chlorides
- Starvation ➡️ metabolic acidosis
- Loss of HCI & hypokalemia ➡️ alkalosis
CIRCULATORY :–
Hemoconcentration ➡️ Decrease in Hb%, RBC values, WBC, eosinophiles
Clinical Course:
Division:
▪ EARLY = no evidence of dehydration or starvation
▪ LATE = evidence of dehydration and starvation
Symptoms:
- Vomiting is increased in frequency with retching.
- Urine quantity increased.
- Epigastric pain
- Constipation may occur.
Signs:
Features of dehydration of ketoacidosis
{eg. dry coated tongue, sunken eyes, acetone smell in breath, rise in temp.}
Investigations:
- Urinalysis = small quantity, dark colour, high specific gravity with acid reaction, presence of acetone, diminished or absence of chloride.
- Biochemical & circulatory changes = LFTS are abnormal (40%) with rise in level transaminase & bilirubin.
- Serum TSH, T3 and free T4 = 60% may suffer from thyroid dysfunction.
- Ophthalmoscopic examination = if patient is seriously ill, retinal haemorrhage & detachment of retina.
- ECG = when there is abnormal serum potassium level.
Diagnosis:
• First confirm the pregnancy.
• USG – used to confirm pregnancy, also excludes other obstetric, gynaecological, or medical cause of vomiting.
Differential Diagnosis:
When vomiting is persistent in spite of usual treatment, other causes of severe vomiting should be considered and investigated.
Complications:
Maternal =
- Neurologic complications like Wernicke’s encephalopathy etc.
- Stress ulcer in stomach
- Jaundice, hepatic failure
- Convulsions & coma
- Renal failure
Foetal =
Foetus is usually unaffected but risk may be due to Low birth weight & preterm birth.
Prevention:
- Take small amount & at frequent intervals
- Drink fluids in between meals & not after the meals.
- Not to lie down immediately after meals.
- Avoid food that cause gastric irritation.
- Avoid high fat food and odors that trigger nausea and vomiting
Management:
Principles –
- maintenance of hydration
- control vomiting
- correct fluid & electrolyte imbalance
- prevent serious complications of secure vomiting
- correct metabolic disturbances (acidosis or alkalosis)
- care of pregnancy.
- correct vitamin deficiencies.
HOSPITALIZATION:
In case of :- Protracted NVP (Nausea, vomiting in pregnancy) despite the use of oral anti-emetics, weight loss > 5%, presence of any comorbidity
FLUIDS:
After cessation of vomiting –
- Oral feeding is paused for atleast 24hrs
- Fluid is given through intravenous drip
➡️ Calculation of amount of fluid to be infused in 24 hours is:
Total fluid [3 litres]
- 5% dextrose (1.5 litres)
- Ringer’s solution (1.5 litres)
**Crystalloids (equal to the amount of vomitus and urine) is also added.
Drugs:
- Antiemetic drugs – • promethazine 25mg or prochlorperazine 5mg IM (twice or thrice daily) • metoclopramide (second line drug)
- Hydrocortisone 100 mg IV (in case of hypotension or intractable vomiting)
- Nutritional supplementation – Vit B, 100mg daily, Vit B6, Vit C, Vit B12
- Ondansetron – safe and effective
To Read, Antiemetic drugs in detail, CLICK HERE.
Nursing care:
- Sympathetic but firm handling of patient.
- Thiamine 100mg IV is injected to prevent Wernicke’s encephalopathy.
- Stress ulcer by proton pump inhibitor (IV).
- Hyperemesis progress chart – to assess progress of patient while in hospital.
- Daily record of pulse, temp., B.P. (twice). ECG, urine.
- Termination of pregnancy is rarely indicated.