GYNAECOLOGICAL EMERGENCIES IN PET ANIMALS

GYNAECOLOGICAL EMERGENCIES IN PET ANIMALS

1. N. Mohanty, Proffesor and head, dept. of Gynaecology Faculty of veterinary science & animal husbandry

Bhubaneswar, Orissa

The classical stages of the canine estrus cycle has been earlier documented1. This was prior to the understanding of the hormones. So his classifications of various stages were based on sexual behaviour and physiologic changes in the reproductive tract. At present the definitions are based on; behavioural, clinical, physiologic, cytologic and endocrinological changes in the bitch.

Prebreeding examination of the bitch prior to breeding should be encouraged with respect to :

1. General physical examination
2. Immunization record
3. Testing for heart worm and other
4. Screening for genetic diseases
5. Radiography – for hip dysplasia (hereditary)
6. Thyroid testing

Understanding the physiology and endocrinology of pregnancy and eutocia in bitch is necessary for preventing, diagnosing and treating the anomalies. Although the exact mechanisms for initiation of parturition has not been completely known, but studies in bitch and other species have provided data that allow veterinarian to understand and identify the problem.

Basing on the endocrinology of canine parturition the following factors can be the contributory factors.

1. Corticosteroids –           Fetal ACTH increased, release of fetal cortisol
2. PGFM (13,14-dihydro –        Increased synthesis and release of PG

15-keto-prostaglandin F2C)

3. Progesterone –           Prepartum decrease to < 1-2 µg/ml
4. Prolactin –           Increase in PRL from 40± 7 µg/ml to 117 µg ± 24 µg/ml within 32 hrs to parturition.

 

Predicting Onset of Parturition:

Predicting day of whelping is difficult as the canine gestation length can range from 57 to 72 days 2.

When canine gestation length is timed from ovulation, the duration is more precise, ranging from 62 to 64 days.

The predictions of delivery date are:

1. Breeding date –    57-72 d from a single breeding
2. Ovulation date –    64 -66 d after serum LH surge (determined by serum LH)
3. Serum P4                                                                              –    1-1.9 µg/ml-63-65 d

2-3.9 µg/ml – 63-65 d

4-10 µg/ml- 62-64d

Ø Parturition within 12 -24 hrs after P4 conc.

drops< 1-2 µg/ml

4. Diestrus vaginal serum –    57d (approx) after onset of cytologic diestrus (decreased superficial cells and increased small intermediate cells)

5. Rectal temperature – Drop to 8°F, between 8-24 hr. prior to parturition
6. Radiographic appearance –    20-22d , spine, skull , ribs of fetuses (prepartum)                        2-9 d, caudal vertebrae, fibula, paws 3-8d, teeth

7. Ultrasonographic appearance –    fetal biparietal and fetal trunk diamt.
8. Onset of lactation –    2 wks before parturition
9. Nesting behaviour –    5-7 d prior to parturition to first stage of labour.
10. Cervical , vaginovestibular and – Near parturition vulvar relaxation
11. Lochia (greenish black – following placental sepration, with whelping occurring discharge)             1-2hr of its presence.

 

The most commonly encountered gynaecological emergencies in pet animals are:

1. Uterine inertia
2. Dystocia
3. Uterine torsion
4. Inguinal hernia
5. Uterine rupture
   1. Septic metritis and toxaemia
   2. Metritis
   3. Hypocalcaemia
   4. Pregnancy toxaemia
   5. Medical induction of parturition

    

   https://www.pashudhanpraharee.com/overview-of-infertility-in-the-bitch/

   1. Uterine Inertia:

   PRIMARY       ¯ Characterized by a failure to expel normal sized fetuses through a birth canal that is normal except for an incompletely dilated cervix.

   It is complete if no signs of second stage labour occurs.

   Etiology—       Mechanical , hormonal , physical and genetic components .

   This occurs when parturition begins normally, but uterine contraction stops before expulsion of the puppy. Mostly occurring with :

   1. Inherited breed predisposition (Terrier) with overstretched uterus containing large
   2. Inadequate uterine stimulation in one or two-pup
   3. Systemic disease- hypocalcaemia
   4. Obesity
   5. Uterine infection in septicemia
   6. Inadequate nutrition
   7. Uterine torsion
   8. Trauma

   Ø Serum calcium measurement in affected bitches

    

   Prognosis- Guarded to good

   SECONDARY – Prolonged uterine contractions failing to expel a fetus.

   A.  Strong and frequent stage II ’!Abdominal straining that fails to produce a pup within 30 minutes.

   1. Perceived failure to start parturition on time.
      1. Perceived failure to progress normally with delivery of puppies once labour has begun.

      Predisposing Factors :

      1. Fetal and maternal factors and many of these occurring together .

      e.g:- Foetal oversize a fetal factor leads to secondary uterine inertia, a maternal factor.

      SO WHILE PREDICTING OR DIAGNOSING DYSTOCIA IT IS ESSENTIAL TO CHARACTERIZE MATERNAL AND FETAL FACTORS.

      During second stage of labour strong abdominal straining or tenesmus is suggestive of pup presence in birth canal.

      Assistance may be necessary if the bitch does not deliver the pup within 30 minutes. Pup lodged in the birth canal can die if complete placental separation is not followed by delivery.

      Obstruction compromises other pups remaining in the uterus.

      Eventually active straining and labour will subside as secondary uterine inertia develops.

       

      A.  Weak or Intermittent stage II’! Abdominal straining that fails to produce a pup within 4 hrs (1st pup) or 2 hrs(between pups).

      After 4 hrs of onset of the stage II labour  Pup is not delivered or 2 hrs between pups is suggestive of infective uterine contraction to advance the foetus through the birth canal.

      These bitches frequently respond to medical management with oxytocin or calcium. Incidence of stillbirth rises as the time interval between delivered pups increases.

      Reliable sign of beginning of whelping ->

      Presence of lochia or uteroverdin (greenish –blackish vulvar discharge) indicates placental separation has begun.

      It has reported that sometimes after the death of the caudal foetus in the uterus before term, lochia will pass and the remaining pups are born normally at term.

      IMPORTANT NOTE:- Passage of lochia from a term bitch signifies whelping to commence within 1-2 hrs . Failure signifies a potential dystocia and if not relieved within 24 hrs the entire litter of pups may die.

      Common observation to be noted by the owner:

      1. Copious amount of clear, water like vulvar discharge – Allantoic or amniotic fluid
      2. Confusion with the placental fluids and
      1. 2. 10% solution of calcium gluconate (0.22 to 44 ml/kg)i/v
         3. Glucocorticoids not to be used (decreases intestinal absorption, enhance renal excretion of calcium)

Oral administration of calcium or D may be of benefit after initial i/vObserving a sac or bubble protruding from the vulva lips – caudal portion of allantochorion.

All these signifies the presence of a pup in the birth canal.

Diagnostic Evaluation5 :

To confirm       –           i. Pregnancy is present

1. Parturition is not proceeding normally

• The cause of dystocia

1. Detect maternal anal/or fetal compromise The necessary evaluation should be based on –

1. Complete history – general health , prior illness, previous reproductive performance (breeding dates), past whelping & dystocia, rectal measurements during pregnancy.
2. Physical – temp.,pulse, respiration rate, capillary refill, hydration status.
3. Thorasic auscultation – cardio pulmonary function
4. Abdominal palpation – fetal presence
5. Palpation of fetal movement and auscultation of fetal heart beats ( absence does not confirm fetal death)
6. Inspection of mammary gland- normal or abnormal secretion of milk
7. Examination of vulva – lochia or blood
8. Digital examination of the vestibule and vagina – ascertain the relaxation of the birth canal, presence or absence of foetus, soft or bony tissue impingement on the birth
9. Abdominal radiography – fetal number , size, position, signs of fetal

Radiographic signs of fetal death –

1. Presence of gas within foetal body cavities or blood
2. Alteration in the spatial relationship between bones of the axial skeleton.

• Overlap of foetal cranial bones

1. Failure of the skeleton to calcify or continue to grow

7. Ultrasonographic examination – Presence or absence of intrauterine fetal viability. it has been suggested that fetal distress can be predicted using ultrasonographic observation of brady cardia when fetal tissue pH reaches 05 and fetal heat rate is 40 to 130 beats/min6.
8. External monitoring devices and hand held Doppler units (Whelp Wise) – Assessing uterine contractile activity and fetal heart

imp. note:-          Fetal heart rate –          < 130 beats/min; poor viability of pups if not delivered within next 2-3 hrs.

< 100 beats /min; immediate veterinary intervention

1. Laboratory evaluation – Complete blood count, serum chemistry (glucose, calcium) urine analysis

Treatment:

1. Manipulative treatment  –

Extracting malpositioned or slightly oversized foetus (snook ovariohook, sponge forceps, clamshell forceps) only these instruments are to be used when fetus is dead or there is adequate room space.

Protruding puppy from vulva – Lubricating the birth canal and grasping with a gauze sponge. Grasping tail or limb are not to be encouraged .

Puppies obstructing the birth canal and barely protruding are to be recovered by C.S.

II.                Medical treatment-

Thumb rule for indicating medical treatment

• Bitch is in good health
• Labour has not been unduly protracted
• Cervix is dilated
• Fetal size is consistent for vaginal

When medical treatment produces a slow response and many pups remain in utero then indicate C.S.

Administration of ecbolic drugs is not indicated in obstructive dystocia The various forms of medical treatment to be considered are;

1. Oxytocin:

Action- uterine contractions and milk ejection Synthetic oxytocin .Half life is 1-2 mins

Safe for both bitch and pups.

But high and repeated doses results uterine hyper stimulation or (uterine tetany) with fetal distress.

Recommended dose – 5-20 units/dog, i/m at 30-40 min interval, poor response may be seen when the extracellular calcium conc. are low

1. Calcium- Added to oxytocin administration

Oxytocin increase frequency where as calcium increases strength of uterine contractions

(myometrial contraction). Combination results a direct action on the rate of Ca ion influx into the myometrial cell .

Dose    – Slow i/v over 3-5 min, 10% calcium gluconate @ 0.2 ml/kg or 1-5 ml/dog s/c., discontinued if the animal is restless or change in the heat rate and rhythm occur.

1. Ergonovine – Ergot alkaloid

Not to be used for treating canine dystocia rather to be used for uterine contraction and vasocerotictism in post partum haemorrhage.

Dose    – 10-30 µg/kg per os or i/m

Combination with oxytocin in women results in less blood loss post partum but it causes nausea, B.P. & vomiting.

1. Glucose for clinical management Oral glucose or 5 to 10% glucose solution i/v
2. Tranquilizers- indicated for
   1. overcoming voluntary inhibition of parturition
   2. facilitate clinical & vaginal

Uses is to be  discouraged

Barbiturates and promazine derivatives are poorly metabolized by fetal liver.

Occasionally, dopamine antagonists (acepromazine) and phenothiazine block dopamine receptors can be given post partum to increase pituitary release of prolactin.

 

 

MEDICAL APPROACHES FOR TREATING CANINE DYSTOCIA

History                                                                             Approach

1 or 2- pup litter or fetal oversize                                                                     C.S.

5 or more pups remaining in uterus                                                                  C.S.

4 or less pups remaining in uterus        1.Oxytocin 0.1 – 2.0IU/kg i/m not exceeding 20IU with a non obstructed birth canal                                            2. If pup is born with 30 mins repeat oxytocin at

30 min interval if delivery slows add calcium

3. If put is not born with 30min of oxytocin admn., give 10% (calcium gluconate 0.2ml/kg) i/v not exceeding 5 ml.

Repeat oxytocin after calcium . If no pup is born after 30 min. C.S.

III   Uterine Torsion:

Relatively uncommon due to long and freely movable uterine horns. One or both horn can twist along the long axis or arround the opposite horn, or the entire body can rotate.

Symptoms        –           Severe pain with abdominal distension

Haemorrhagic vulva discharge Tachycrdia

Signs of shock Dystocia.

Severe torsions can cause obstruction of the blood supply to the uterus resulting in thrombosis or rupture of the uterine vessel, congestion, shock, fetal and /or maternal death. Rupture may occur at parturition.

Diagnosis         –           From clinical signs

Ultrasonographic exam. Exploratory laparotomy

Treatment         –         Immediate surgical correction (hysterotomy to remove foetus or hysterectomy if thrombosis and gangrene are present)

 

IV  Inguinal Hernia:

Occasional occurrence when pregnant uterine horns enter through inguinal ring and can result in dystocia.

Congenital defects       –           Basset hound, Cairn terrier, Basenji, Pekingese, West Highland White terrier.

Treatment        –           1. Surgical repair of the hernia for preventing ischemic compromise.

2, C.S. for delivery of term pups.

 

V  Uterine rupture:

Rare in bitch

Follows uterine trauma or trauma

Condition may go undiagnosed until dystocia results when puppies fail to enter the birth

canal.

Death of foetus immediately when fetus expelled to abdominal cavity and be resorbed (if

fetal calcification has not occurred ) or retained as mummified foetus. Possible sequel –                                    Peritonitis.

III  Septic Metritis and Toxaemia:

It is evident by 48-72 hr after intra uterine fetal death.

When dystocia gets undiagnosed or untreated, the entire litter dies within 24 hrs.

The foetus then serves as the substrate for infection with ascending vaginal bacteria.

Diagnosis         –           History or ultrasonography

Symptoms        –           Elevated rectal temperature, degenerative left shift of WBC. Treatment        –                        Aggressive fluid and antibiotic therapy

Hysterotomy.

IV      Metritis:

Acute puerperal metritis a disease of immediate post partum period (0 to 7d post whelping) is severe inflammation or the endometrium and myometrium that causes systemic illness in the bitch.

Etiology-          Retained placenta Retained pups

Macerated and decomposed pups Prolonged delivery

Bacteria thrive in retained or devitalized tissues leading to inflammation of endo- and myometrium and if untreated leads to septicemia and toxaemia.

Symptom-        Depression

High rectal temp.(103°-105°F)

Putrid, reddish brown uterine discharge Hypovolumic shock from dehydration Septicemia or endotoxaemia

Diagnosis-   Cytologic evaluation of uterine discharge

1. Neutrophils – degenerative
2. Bacteria

• Erythrocytes ,endometrial cells and muscle fibers from decomposing fetuses
• Leukopenia with immature

Treatment-                   1. Treating shock- replacing fluid deficits

1. Initiating broad spectrum antibiotics
2. Dextrose i/v (if hypoglycemia)

Once the bitch is stabilized, surgical intervention is required to remove remaining placenta and/or devitalized fetal or uterine tissues.

Then culturing the contents.

Merits of infusing the uterus with antibiotics or draining uterine contents are unknown. Antibiotic infusions may be contraindicated9 as it impede phagocytic function of uterine neutrophils. Antiseptic solutions infusion may damage uterine neutrophils .

Role of various ecbolic agents in treatment is uncertain . Using ergonovine is not recommended because of uterine rupture.

Efficacy and safety of using PGF2á have not been studied carefully. Hormones as in bovine cases it may be judiciously used depending on the integrity of the myometrium and uterine wall.

VIII. Hypocalcemia: Eclampsia, Puerperal tetany

Depletion of calcium in the extracellular compartment characterized by nervousness elevated body temp., dry mouth ,sclera, panting , restlessness, whining, tremors, staggering. It may occur prior to parturition and is far more common during the first few weeks post partum. Observed generally in smaller breeds.

Symptoms       – Restlessness ,pacing, panting, reluctance to care for the pups, stiffness before the onset of muscle tremors, tetany and convulsions.

Diagnosis        1. Hyperthermia- 105°F (due to increased muscle activity)

2. Electrocardiogram – Deep, wide T waves, prolonged Q-T interval Taller R waves
3. Blood calcium- < 7 mg/100ml (normal 9-11mg/100ml) Confirmative
4. Blood glucose- Normal (differentiating from pregnancy toxemia) Differential diagnosis of seizures – epilepsy, meningoencephalitis,
5. Magnesium – Normal

Treatment       1. Slow i/v administration of calcium gradual cooling the bitch. treatment.

1. 1. 1. 2. 1. 10% solution of calcium gluconate (0.22 to 44 ml/kg)i/v
            2. Glucocorticoids not to be used (decreases intestinal absorption, enhance renal excretion of calcium)
            3. • Oxytocin; Not known whether it can induce parturition in term bitch or with elevated
                 1. 20/µg/kg every 8 hr
                 2. 30µg/kg every 12 hr for 72 hr
                 3. 250µg/kg every 8 hrs for 4 days.Oral administration of calcium or D may be of benefit after initial i/v treatment.
                    2. Removing pups to reduce lactational drainage. Prevention –                            Balanced diet with P ratio (1:1 to 1:2:1)

                    Dietary cation–anion difference may be more crucial than calcium intake during pregnancy in preventing hypocalcaemia . Feeding highly anionic (acidic) diet were more responsive to parathyroid hormone , enabling quick mobilization of calcium from bone .

                    Current recommendation for preventing eclampsia in bitch –

                    Feeding diets during pregnancy that are not excessive in calcium. So during lactation calcium supplementation to bitches is imperative for preventing Eclampsia.

                    Dry dog feed diets – high percentage of soybean meal or bran

                    IX Pregnancy Toxaemia:

                    Can occur days to weeks before parturition and is also associated with prolonged gestation and dystocia.

                    Etiology-          Inadequate nutrition Bitches with large litters

                    Ø         Ketonuria without glucosuria is a hallmark of prepartum pregnancy toxemia in bitch.

                    Symptoms        –           Weakness, inability to stand, seizures and coma.

                    Hepatic lipidosis

                    Diagnosis         –           Urine ketones in the absence of urine glucose hypoglycemia Treatment       –                        Supplemental nutrition

                    I/v dextrose administration

                    Medical induction of parturition with glucocorticoids.

                     

                    X.    Medical Induction of Parturition:

                    Indication –   Pregnancy compromising with maternal health (Preg. Toxaemia) Preterm induction of parturition in the healthy bitch has not been well studied. The common drugs that can be tried are:

                    1. Glucocortricoids;

                    Dexamethasone is effective in terminating with 2 to 16 days after initiation of treatment.

                    Dose – 0.2 mg/kg/os TID for 5 days followed by

                    0.16 to 0.02/kg/is TID for next 5 days

                    Termination of canine pregnancy of 57 -58 day at a dose rate of 0.4 mg/kg parenterally one time.

                    Long term glucocorticoids enhance viability of pups by enhancing maturation of fetal lungs .

                    • Prostaglndings;

                    Terminate pregnancy after 3 to 5 day at the dose rate given S/C or i/m

                 Majority of the fetus expelled are live with placenta intact.

               P4conc.

               • Mifipristone(RU-486)

               Progesterone antagonists can induce premature delivery in bitches. Bitches on 32d

               pregnancy can be induced with mifepristone, expelling dead foetus or dark mucoid vulvar discharge. But it is unknown whether it can induce near term.

                

               XI Retained Fetal Membrane:

               The persistence of green genial discharge after 12 hrs. of birth of last puppy is indicative of a retained after birth.

               Vaginal exploration with finger & by fiddling to bring out the umbilical cord & gentle traction is applied to withdrawal the placenta.

               The uterus is palpated through the abdominal wall& detect it’s presence (in small bitch) as an egg like distension. Fine parts of the bitch raised & firm pressure is applied to the distended part. By this separation occurs & the placenta is expelled immediately.

               Treatment is to be repeated after a few hours.

               Oxytocin is administered half an hour after the last fetuses have been delivered for expulsion of the terminal placenta if present.

               Radiographic examination of the abdomen may be undertaken.

               In no response by Oxytocin administration or abdominal manipulation , lapratomy is indicated for milking the fetal membrane along the uterus towards the cervix. If this fails hysterotomy can be performed to relieve them.

               References:

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               2. Concannon, , Whaley,S. and Lein, D. (1983). Canine gestation length:Variation related to time of mating and fertile life span of sperm. Am.J.Vet.Res., 44: 1819-1821..
               3. Jones, E. and Joshua, J.O. (1983). Some problems of parturition. In Reproductive Clinical Problems in the Dog. London, Wright-PSG. Pp. 80-84.
               4. Bennett, (1980). Normal and abnormal parturition. In Morrow, D.A., (ed). Therapy in Theriogenology. Philadelphia, W.B. Saunders. Pp. 595-606.
               5. Johnston, D., Root Kustritz, M.Y. and Olson, P.N.S. (2001). Canine and Feline Theriogenology. Philadelphia.
               6. Monheit, G., Stone, M.L. and Abitol, M.M. (1988). Fetal heart rate and transcutaneous monitoring during experimentally induced hypoxia in the foetal dog. Pediatr. Res., 23: 548-552.
               7. Batra, (1986). Effect of oxytocin on calcium influx and efflux in the rat endometrium.

               Eur. J. Pharmacol., 120: 57-61.

               8. Roberts, J. (1986). Veterinary Obstetrics and Genital Diseases (Theriogenology). Woodstock, V.T., pp. 231.
               9. Gilbert, O. and Schwark, W.S. (1992). Pharmacologic considerations in the management of peripartum conditions in the cow. Vet. Clin. North Am. Food Anim. Pract., 8: 29-56.
               10. Threlfall, R. (1995). Ohio State University, cited by Johnston et al., 2001. Pp. 126.
               11. Maher, E., Cliver, S.P. and Goldenberg, R.L. (1994). The effect of corticosteroid therapy in the very premature infant: March of Dimes Multicentre Study Group. Am. J. Obstet. Gynaecol., 170: 869-873.
               12. Concannon, W., Yeager, A. and Frank, D. (1990). Termination of pregnancy and induction of premature luteolysis by the antiprogestagen, mifepristone, in dogs. J. Reprod. Fertil., 88: 99-104..
               13. Arthur, H., Noakes, D.E. and Pearson, H. (1989). Veterinary Reproduction and Obstetrics (Theriogenology). 6th ed., Bailliere Tindall, London, UK.https://www.researchgate.net/publication/333716708_Gynaecological_problems_in_she_dogs