(Postpartum hypocalcemia, Periparturient hypocalcemia, Puerperal tetany, Eclampsia)

What is eclampsia?

Eclampsia (hypocalcemia or puerperal tetany) is an emergency medical condition associated with a life-threatening drop in blood calcium levels that occurs in nursing mothers. Eclampsia most commonly occurs when the puppies are one to four weeks of age and the mother is producing the most milk.

The cause of eclampsia may be due to:

• excessive loss of calcium from the mother to the developing fetal skeletons,
• calcium supplementation during pregnancy,
• producing milk after birth,
• not receiving a balanced premium growth and development diet while pregnant and nursing, or
• a hormonal problem with the parathyroid gland.

Females that are particularly good mothers, especially attentive to their puppies, seem to be more likely to develop eclampsia. Breeds such as Chihuahuas, Pomeranians, Toy Poodles, Miniature Pinscher, Shih Tzu, and other small breeds are at an increased risk.

Types

While eclampsia normally occurs after the dog has given birth, it is possible for the condition to develop at different stages in the pregnancy:

• Prepartum – Symptoms of eclampsia may begin to appear before birthing occurs. Mild eclampsia may reduce the effectiveness of myometrial contractions, which in turn induces uterine contractions.
• Parturition – It is possible for signs of eclampsia to appear during the actual birthing process. If the eclampsia is mild in severity, it may slow the labor’s progression without exhibiting any other signs.
• Postpartum – Postpartum eclampsia is most common in the first five weeks after birth, when lactation is at its peak. This is because the mother’s body is unable to keep up with the calcium it is providing to the offspring.

Symptoms of Eclampsia

Eclampsia is an emergency condition and animals that exhibit signs should be relieved from nursing, and the veterinarian contacted immediately. Signs vary depending on the severity of the condition.

Diagnosis of Eclampsia 

• History and signs
• Estimation of serum calcium level:- Serum calcium concentration <7 mg/dL 

Differential Diagnosis

• Hypoglycemia (low blood sugar), conditions caused by poisons/toxins, and neurological disorders that may cause seizures
• Metritis (inflamed uterine wall) and mastitis (inflamed mammary gland), which may cause irritability and increased body temperature
• Hypoparathyroidism (deficit of parathyroid hormone in the blood), in instances where there are small amounts of serum PTH

Treatment of Eclampsia

• Slow intravenous administration of organic calcium compounds (20% calcium borogluconate or 10% calcium gluconate) at a rate of 1–1.5 mL/kg for dogs and 2.5 mL/kg for cats.This usually results in rapid clinical improvement within 15 min
• During administration of calcium, heart rate should be carefully monitored for bradycardia or arrhythmia by auscultation

Prognosis

If treatment is started promptly, most bitches usually respond well to calcium treatment, and eclampsia is successfully controlled.

Dogs that become comatose or have extremely high body temperatures for a long period have a worse prognosis. 

Can eclampsia be prevented?

A number of authors have speculated that eclampsia is a nutritionally related disorder of pregnancy or lactation resulting from either the overfeeding of high calcium-containing animal protein (egg or meat) or the feeding of dog foods containing cereals with phytate (because phytate binds ionized calcium, making it biologically unavailable). As a result, recommendations to prevent eclampsia involve feeding a balanced (puppy or kitten) formula commercial pet food without additional vitamin or mineral supplementation during the second half of gestation. This gestational diet should contain between 1.0% and 1.8% calcium and 0.8% and 1.6% phosphorus. Dietary supplementation with any dairy products during gestation should be avoided as they disrupt normal calcium-phosphorus-magnesium balance in the diet and may promote the development of eclampsia. The postpartum diet should be balanced for all lifestages, including lactation, and contain at least 1.4% calcium, with a calcium:phosphorus ratio of 1:1.3