I’ve spent more time in front of digital screens during the COVID-19 pandemic than to which I wish to admit. I’ve watched some new shows and rewatched some others. This morning, a re-run of the heart-wrenching Downton Abbey episode that saw Lady Sybil die of eclampsia had me feeling all sorts of ways again. Did you know cats and dogs can develop eclampsia too? This week’s post is all about this postpartum emergency, so I hope you find it helpful. Happy reading!
Eclampsia – What is it?
Eclampsia is also called periparturient hypocalcemia, puerperal tetany, and postpartum hypocalcemia. It’s a potentially life-threatening condition that typically develops several weeks after queening/whelping (e.g.: 21-45 days postpartum). Occasionally, eclampsia develops during late gestation (e.g.: last 20 days of pregnancy).
Requirements for calcium increase during late gestation and queening/whelping for several reasons:
- Developing fetal skeletons
- Lactation demands
- Decreased responsiveness to parathyroid hormone (the hormone that regulates calcium in the body) due to an acid-base change called respiratory alkalosis induced by increased panting
- Uterine contractions during labor
Increased calcium demand is exacerbated by reduce calcium intake because queens and bitches normally often have hyporexia (reduced appetite) during late gestation and queening/whelping. Calcium supplementation in late pregnancy and feeding a diet with an inappropriate calcium:phosphorus ratio may also contribute to the development of hypocalcemia (low calcium) because the regulatory mechanisms controlling calcium metabolism are suppressed.
What does it look like?
Eclampsia occurs in cats and dogs who recently queened/whelped and are currently lactating. This condition may also develop in those for whom birth and lactation are impending. Small and toy breed dogs, as well as mothers who queen/whelp large litters, are over-represented.
Calcium is necessary to maintain the integrity of many cell membranes throughout the body. When calcium levels decrease too much, nerve fibers can spontaneously discharge. This manifests in a variety of ways:
- Excessive panting
- Muscle fasciculations
- Muscle twitches/tremors
- Tachypnea (increased respiratory rate)
- Ataxia (unsteadiness while walking)
- Tetany (involuntary contraction of muscles)
- Behavior change (staring into space, not paying attention to kittens/puppies)
How is eclampsia diagnosed?
Veterinarians will perform a primary survey when presented patients with muscle tremors and/or seizures. They will evaluate the ABCs – airway, breathing, and circulation – in patients presented for emergency concerns. Affected patients typically have elevated body temperatures because excessive skeletal muscle activity creates a lot of body heat. A non-invasive blood test can confirm hypocalcemia, but false-negative/normal results are possible. As such, a diagnosis of eclampsia is based on:
- Compatible history
- Appropriate physical examination findings
- Response to treatment
How is it treated?
With early recognition and treatment, the prognosis for eclampsia in cats and dogs is good. Treatment is relatively straightforward. Affected patients require calcium supplementation. For severely affected patients, veterinarians will administer an intravenous injection of a medication called calcium gluconate. During the injection, electrocardiography (ECG/EKG) should be monitored closely because abnormal heart rates can develop.
After intravenous administration of calcium, veterinarians will also initiate oral calcium supplementation. Multiple small doses throughout the day are needed because large doses of oral calcium frequently induce vomiting. Treatment is needed until kittens and puppies are weaned.
Kittens and puppies should be weaned if they’re old enough to eat on their own. If they’re not old enough to be weaned, one can provide supplemental meals of an appropriate milk replacer to reduce the queen’s / bitch’s lactation demands. However, if eclampsia recurs with this supplemental approach, then kittens/puppies must be weaned and hand-raised.
The take-away message about eclampsia in pets…
Eclampsia is a potentially life-threatening postpartum emergency in cats and dogs characterized by markedly decreased blood calcium. Affected patients may be restless, have muscle twitching and tremors, and can readily develop seizure activity. Diagnosis is based on a compatible history and physical examination, as well as an appropriate response to calcium supplementation. Prognosis is generally good with timely identification and intervention.
To find a board-certified veterinary theriogenologist (reproduction specialist), please visit the American College of Theriogenologists.
To find a board-certified veterinary emergency and critical care specialist, please visit the American College of Veterinary Emergency and Critical Care.
Wishing you wet-nosed kisses,