Thursday, June 26, 2014

1389. FINAL Copy - MVA - Guidelines on pyometra treatment email to the MVA



Recent Advances in Veterinary Practice No.3
Myanmar Veterinary Association, July 5, 2014

GUIDELINES ON TREATMENT OF PYOMETRA CASES IN DOGS AND CATS
Dr Sing Kong Yuen, BVMS (Glasgow), MRCVS
Founder of Toa Payoh Vets, Singapore. 
www.toapayohvets.com, judy@toapayohvets.com

Pyometra is an infected uterus filled with pus. The uterine lining (endometrium) becomes cystic and hyperplastic due to the effects of oestrogen and progesterone. Bacteria from the vagina enters the cervix to invade the uterine lining leading to inflammation and pus formation.  

If the cervix remains closed, the pus accumulates in large quantities inside the uterus (closed pyometra). If the cervix is open, the pus is discharged via the vagina (open pyometra).  (VIDEO & IMAGES)

If there are ovarian remnants after spay, the stump of the uterus may become infected (stump pyometra). This occurs any time after ovariohysterectomy.  (IMAGE CAT STUMP PYOMETRA X 2)

In Singapore, almost all home cats are spayed to prevent them caterwauling (loud cries of heat). So pyometra in cats is uncommon.  However, many dog owners do not spay their dogs for reasons such as cruelty and therefore pyometra of older bitches is encountered often .

Yangon appears to have a higher incidence of pyometra in cats and dogs as they have been treated with the synthetic progesterone (Depo-M or Contracep)  IM every 3-4 months to suppress the heat cycle.   (IMAGE OF DEPO-M & CONTRACEP). However, client education has led to more owners opting for ovariohysterectomy (IMAGE OF DOG BOMA).   

This paper shares my experiences with the treatment of pyometra for the last 40 years. I graduated from Glasgow University in1974 and am still practicing.  My guidelines are as follows:

1. A correct diagnosis is important.
1.1 History of estrus. Do a thorough physical examination including weighing the dog, taking rectal temperature and checking for false pregnancy or mating.

TIP. Always ask the owner when the vomiting intact female dog has the last estrus.  Pyometra occurs usually 1-12 weeks after estrus. I see many cases around 2 months after estrus. Pyometra may co-exist in pregnancy (20-24 days after ovulation) but it is rare.

1.2 Clinical signs. Important ones are fever, polydipsia, polyuria, abdominal swelling, vaginal discharge and nipple discharge of false pregnancy. Many owners do not provide correct information saying that the vomiting dog has been fed a wrong type of food and had diarrhoea. I had a case when the vet misdiagnosed the closed pyometra as acute gastroenteritis (IMAGE OF HUSKY). The dog died of septicaemia and shock when I did the emergency ovariohysterectomy. Some owners say that the dog does not have polydipsia but has polyuria.

2. Uterine palpation (large uterus for closed pyometra). Abdominal pain or discomfort (dog bites) may be present in a swollen abdomen.

TIP. Practise abdominal palpation in every dog or cat  and you will be able to feel swollen loops of uterine horns in the abdomen. The radiographs will show the swellings (IMAGE OF SONIA, Jack Russell) of closed pyometra.

3. Vaginal discharge (serosanguinous or mucopurulent) is seen in open pyometra (IMAGE & VIDEO).

4. Blood test. CBC/Biochemistry. Leucocytosis, neutrophilia and thrombocytopenia in closed pyometra cases. Anaemia. High serum BUN and creatinine will point to kidney damage.  

TIP. Always advise a blood test to screen the health of the dog and possible kidney damage to determine the anaesthetic risks and prognosis. Some closed pyometra cases may have permanent kidney damage and will continue to vomit even after spay as in one case of a Miniature Schnauzer whose owner’s father procrastinated surgery. The owner was satisfied that the vomiting was due to kidney damage rather than from my surgery as I had interpreted the high serum BUN and urea to her from the blood test.  Without this blood evidence, some owners blame the vomiting on the vet doing an incompetent spay.   

5. Imaging
5.1 Survey radiography may show large distended uterine horns or loops in closed pyometra.
5.2 Ultrasonography shows thickened uterine wall (cystic endometrial hyperplasia and intraluminal fluid (pus). Normal uterine wall cannot be detected by ultrasonography.

6. Client Education & Informed Consent Form.
6.1. Pyometra is a medical emergency. Prognosis depends on the health of the dog as shown in the blood test results of CBC/Biochemistry as well as physical examination.
6.2  Informed consent for anaesthesia and surgery explaining the high risks involved esp. for old dogs. This is important as there have been litigation against Singapore surgeons who have not fully explained the risks of anaesthesia and surgery.
6.3  An estimated amount of medical costs must be given to the owner before the surgery. A pyometra surgery and anaesthesia in small breeds cost around $800 in Toa Payoh Vets in 2014.  

PRE-OP STABILISATION
1. Immediate I/V fluid therapy, antibiotics and pain-killers for 1-2 days. I usually give Hartmann’s, dextrose and amino acids, baytril and spasmogesic IV. The dog is an in-patient.

ANAESTHESIA & SURGERY
1.  I use 25-50% of the calculated dosage I/V for sedation/induction depending on the health of the dog. Then I intubate and maintain with isoflurane + o2 anaesthesia. If the dog is very weak and lethargic, I use entirely isoflurane + O2 anaesthesia and find this to be very effective and safe.

1.1 My calculated dosage is as follows: For a young 10-kg dog, Domitor + Ketamine IV = 0.4 ml + 0.5 ml respectively.

1.2. For very old (over 10 years) dogs and/or in poor health, I use only isoflurane + oxygen gas.

2. Clipping and cleaning to be done before sedation outside the operating room reduces anaesthetic time and risks.

3. Make a long incision carefully to get the swollen uterus out easily and without rupturing the friable parts, contaminating the abdomen with pus.

TIP. The full bladder may be just below the skin. If the vet is not careful, the bladder may be cut spilling urine into the peritoneum.

3.1  I use the 3-haemostat method to clamp and ligate. I release the middle of the 3 haemostats. Then I ligate on the clamped grooved area vacated by the middle of the 3 haemostats.

TIP. I see some vets use only 2 haemostats and do not ligate over the clamped area. So, the ligature slips leading to bleeding.  Some vets using this method ligate two the ovarian ligament in two areas instead of the usual one spot.

For the uterine body, I usually ligate the clamped area of the middle of the 3 haemostats. In big breeds, I used the inverting continuous suture to close the stump and ligate the stump.

TIP. Be careful. Avoid contamination of the peritoneum with pus leaked from the uterus.  

4. Sutures. For medium to large breed dogs, I use 2/0 braided absorbable sutures (Polysorb). For small breeds I use 3/0 sutures. My associate vet, Dr Daniel prefers the monofilament absorbable sutures (Monosyn).

5. I use Anti-sedan IM to reverse and abolish the effects of Domitor sedation in cases where the dog is still not conscious after the surgery. The dog is usually awake within 5 minutes of the injection.

6. Post-op Nursing. The dog is hospitalised around 3 days to lower the medical costs. She goes home with antibiotics for another 10 days and an Elizabeth collar. Tolfedine pain-killers are given for the first 4 days.

7. Outcome. If the dog is not extremely ill, she recovers very well from the surgery. The blood test is useful in client education as regards any permanent kidney damage (high serum BUN and creatinine and phosphous).

8. Practise evidence-based medicine as clients are better educated and have high expectations. Some 10 years ago, in one case, the dog kept vomiting and died despite being spayed. I did not do the blood test to check for kidney damage as the owner wanted the cheapest medical cost. Her family members sent mass e-mails to everyone in Singapore advising them to avoid me. There are strangers and a doctor who phone me to let me know.  Nowadays, they use Facebook or pet forums to voice their grievances against the vet.

8.1 AMA (Against Medical Advice). Nowadays, I give the client a written record that he does not want blood tests, X-rays or procedures as advised by me. I have the written evidence in case of litigation or complaint. In computerized records, there is the allegation of falsifying evidence by deleting the earlier record but vets using manual records need to keep proper records to protect their reputation.

SURGERY FOR STUMP PYOMETRA
Make a long incision to access the retained or remnant ovarian tissues located caudal to the kidney area. The remnant ovary is usually cystic and enclosing the sutures. (IMAGE).

MEDICAL TREATMENT FOR VALUABLE BREEDING FEMALE DOGS & CATS
1. PGF2alpha is an effective pregnancy terminating drug. It causes uterine contractions to expel the pus. In closed pyometra, the uterus may rupture. I have no experience with this treatment.

However, a senior vet in Singapore had one successful case. He incised the linea alba to be able to view the swollen uterine horns. He passed catheters into the uterine horns to suck out the pus and pumped normal saline and antibiotics to irrigate the uterus. The Pekinese gave birth to one pup at the next cycle.     

CONCLUSION
In most practices, the client wants “cheap and good” surgery. Sometimes the kinder vet tries to reduce medical costs by not taking blood tests or doing only one view in radiography. No ultrasonography will be done. It is best to practice evidence-based medicine by taking blood test and X-rays. Pyometra is a medical emergency and if the dog does die on the operating table, all family members feel that the vet is incompetent. After all, he has not done blood tests which other vets would have done.    
A Video of one of my recent case of closed and open pyometra will be screened. It is at:  
http://www.youtube.com/watch?v=J9WJqmVPfw8.

Written notes about the video:

When the vet (myself) said that the dog had a very low chance of survival on the operating table and the medical costs were high in this closed-open pyometra case, the owner felt that it would  a waste of money paying for such a high risk anaesthesia.  He decided to bring the dog home after my I/V treatment to die at home.

But I noticed that there was this 12-year-old boy who cried his heart out. Some vets don't follow up as the owner had decided and they had no time to "solicit" for business and risk being rejected.

But this little boy loves this 14-year-old dog very much as tears streamed down his face when the father decided on no operation. He knew the outcome would be death from septicaemia (leucocytosis, neutrophilia, thromobocytopenia in the blood test).

I phoned the father (owner) the next morning. The dog was still passing bloody vaginal discharge and had become lethargic.

I reduced the surgical costs to give this high anaesthetic risky canine patient a chance to live.

Time was running out on her as she became sick again. Her serosanguinous vaginal discharge flowed out like a burst dam.

If she survived the operation, the little boy would get his companion back to health and that was what mattered to me in this case.

 "Don't wait till you have finished work this evening to bring the dog down," I advised the father. "Bring her down now while she still has a fighting chance to live. Time is running out."

Dr Daniel operated immediately in the afternoon. The dog was warded one night. The little boy was most happy to have his companion back home the next day with his mother. "Are you happy now?" I asked him as he carried his friend carefully into the car. "Yes," he beamed to me his best smile.

This is a case where a vet can make a difference if he take the time to follow up before time has run out for a little boy's best friend. Now, as at Jun 25, 2014, around 2 months after spay, the 14-year-old dog is normal.

This case encourages the vet to care for the sick pyometra dog by following up with the owner the next day. Reducing the medical costs would be needed in some cases where money was a concern.

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