A. DEVELOPMENT

Hypocalcemia, or eclampsia, is a low concentration of calcium in the body. Another name for this condition is puerperal tetany. This condition should not be confused with preeclampsia in women, a syndrome of high blood pressure and protein loss that occurs during pregnancy. Eclampsia in dogs occurs most commonly in small-breed dogs nursing a large litter. Onset of clinical signs is most common at peak lactation, 2 to 3 weeks after whelping, when the demand for calcium for milk production outstrips the bitch’s ability to draw calcium from her bones.

B. SIGNALMENT

Breeds described in the literature as predisposed to eclampsia include the Chihuahua, miniature pinscher, shih tzu, miniature poodle, Mexican hairless, and Pomeranian. In general, occurrence is more likely if the ratio of body weight to litter size is small.

C. HISTORY AND CLINICAL SIGNS

Although the onset of clinical signs of eclampsia is most common at peak lactation, hypocalcemia may develop during pregnancy or at whelping. Initial clinical signs include neglect of the pups, restlessness, and scratching at the face. There is quick progression to wobbly gait, dilated pupils, disorientation, and muscle tremors. In the final stages, seizures and stiff paralysis are seen. In a report of 31 cases of eclampsia in dogs, six dogs did not show this classic progression of signs.

D. DIAGNOSIS

Tentative diagnosis is made based on the signalment and history. Definitive diagnosis requires identification of low calcium concentrations in blood.

E. TREATMENT

Calcium is administered intravenously to effect. The heart must be evaluated throughout administration of calcium, preferably with an electrocardiogram (ECG). If calcium is infused too quickly, arrhythmias and abnormalities in heart rate may be induced. Once the dog is stabilized, calcium also can be infused subcutaneously. It is important to use calcium solutions appropriate for the route of administration; some calcium solutions are irritating and will cause loss of the skin over a site of subcutaneous administration. Once the dog can be sent home, oral calcium and vitamin D should be administered for the duration of the lactation. It may be beneficial to take the pups off the bitch for 12 to 24 hours. If clinical signs of eclampsia recur when the pups resume nursing, they must be removed and hand-fed or weaned.

F. PROGNOSIS

Prognosis depends on the bitch’s response to therapy. Most bitches that respond quickly to calcium therapy recover well.

Eclampsia may recur at subsequent lactations. The best way to prevent this is to feed a well-balanced diet during pregnancy, without calcium supplementation. Administration of calcium supplements during pregnancy shuts down the bitch’s calcium regulatory system; so, when she needs to draw calcium from bone during lactation, her body cannot respond and clinical signs of eclampsia develop. It is much better to wait to supplement calcium orally until at or after whelping.

A. DEVELOPMENT

Metritis is infection of the uterus. This is not the same as pyometra, which is infection overlying the uterine abnormality termed cystic endometrial hyperplasia (see Chapter 16). Metritis occurs when the normal flora of the reproductive tract are allowed to colonize the uterus postpartum. This most commonly occurs following dystocia, retention of a fetus or a placenta, or prolonged delivery.