Thursday, May 29, 2014

What is Your Diagnosis and Treatment? Acute onset of a vaginal mass in a pit bull.

Betty, a 2 year old in tact female pit bull.
"Betty" is a 2 year old in tact female pit bull with an acute onset of a vaginal mass. The owners just noticed the problem today and presented her to the emergency service. She had a small amount of pinkish vaginal discharge for a few days before her owners discovered the mass. They do not remember when she was in heat last. She had no other history of any medical problems.

The dog was bright and alert and her physical examination was unremarkable except for the vaginal mass. 
Vaginal mass on Betsy

What additional diagnostic tests would you do?

What is your diagnosis and how would you treat this problem?

Post answers either here or on Facebook.

Monday, May 19, 2014

Postoperative Pain Control in Dogs and Cats: How much is enough?

Postoperative comparison of four perioperative analgesia protocols in dogs undergoing stifle joint surgery
Kerrie A. Lewis, DVM, MS; Richard M. Bednarski, DVM, MS; Turi K. Aarnes, DVM, MS;
Jonathan Dyce, MA, VetMB; John A. E. Hubbell, DVM, MS
(J Am Vet Med Assoc 2014;244:1041–1046)

Summary

In this study the authors compared 4 protocols for perioperative analgesia in dogs undergoing TPLO surgery for the treatment of a ruptured cruciate. Forty-eight dogs were included in the study. The dogs were randomly assigned to receive one of the following protocols:
            IM premedication with morphine
            CRI of morphine, lidocaine, and ketamine (MLK)
            Lumbosacral epidural of morphine and ropivicaine
            Both MLK and the epidural of morphine and ropivicaine.

All dogs received NSAIDS after surgery. Pain and sedation scores were collected from the dogs for 24 hours postoperatively. Morphine was administered as a rescue analgesic if a pain score of > 5 of 24 was determined.

No differences in anesthetic parameters were found between groups, and no differences in postoperative pain parameters (pain scores, sedation score, rescue analgesia requirement, or time to first rescue analgesia administered after surgery) were found. The authors concluded that all 4 analgesic protocols were acceptable for postoperative analgesia for the first 24 hours.

Commentary

The most conservative analgesic protocol, i.e., premedication with morphine alone, was as effective as the more aggressive protocols. Based on the results of this study, the conservative approach of an opiod premedication combined with postoperative NSAID therapy appears to be an appropriate method of pain control in dogs having TPLO.

This well designed study provides us with valuable clinical information. The authors chose dogs having TPLO, which is a painful surgical procedure involving osteotomy of the proximal tibia followed by plate fixation. The fact that 1 preoperative dose of morphine combined with postoperative non-steroidal therapy provided acceptable postoperative analgesia suggests that more aggressive pain management may not be necessary.

The findings of this study bring up a larger question: what is the appropriate level of pain control for postoperative patients? How much analgesic therapy is needed after other types of surgeries such as abdominal or thoracic procedures?   An aggressive approach to pain management ensures that we are addressing the needs of the patient, however, all medications have side effects and these must be considered when formulating our approach.  Regurgitation, aspiration pneumonia, dysphoria and excessive sedation are all complications that are associated with drugs used for analgesia.  The subjective nature of our pain assessment methods makes it difficult to know when we are administering an appropriate amount of analgesia. Hopefully more studies like this one in which objective measures were used to assess sedation and pain will be conducted to answer these questions.

What is your opinion? What routine analgesic protocols do you use and what is your experience with them? Leave a comment on the blog or on facebook; I would love to hear your thoughts.            

Saturday, May 10, 2014

Surgical Correction of Stenotic Nares: Or how to do a nose job in a brachycephalic dog.

Fig. 1: normal anatomy of the nose in a dog
From: Evans HE. The respiratory system. In Evans, HE, editor, Miller’s Anatomy of the Dog. 3rd edition, WB Saunders, 1993, pg. 464.
Stenotic nares are one aspect of brachycephalic syndrome, the upper airway obstructive disorder seen in brachycephalic dogs such as bulldogs, pugs, and Boston terriers. Stenotic nares are characterized by a malformation of the alar folds resulting in abnormally small nostrils.

The mobile portion of the external nares is comprised of 3 cartilages, the dorsal and ventral parietal cartilage and the accessory cartilage.  The alar fold (also called the wing of the nostril or the lateral cartilage) is the nasal structure that forms the lateral border of the nostril.(1)  This fold is collapsed medially in dogs with stenotic nares.  During inspiration, the alar fold may collapse further, causing complete occlusion of the nostril.

Surgical Procedure

Fig. 2: Wedge resection for correction of stenotic nares in brachycephalic dogs.
From: Fingland RB, Obstructive upper airway disorders, in: Saunders Manual of Small Animal Practice, 3rd ed., editors: Birchard SJ, Sherding RG, Elsevier, St. Louis, pg. 1651.
The surgical procedure to alleviate stenotic nares is either to remove a wedge of tissue from the alar fold, or to do a subtotal excision of the alar fold. The author usually performs the wedge excision technique which is described here. (Fig. 2) Position the animal in ventral recumbency with the head at the end of the operating table.  The nose is surgically prepared. A scalpel with #15 blade is used to make angled incisions in the alar fold so the portion to be removed in the shape of a triangle. (Fig. 3)
Fig. 3: Angled incisions made to begin triangular wedge excision of alar fold.
Be sure to include a pie-shaped section of cartilage from the inside of the alar fold in the excised section. Remove the tissue via sharp dissection.  Control hemorrhage with direct pressure.  Place simple interrupted sutures (4-0 Monocryl) in the alar fold, taking bites from inside the nostril to the outside (Fig 4). 
Fig. 4: direction of suture bites for closure of the alar fold after wedge excision.
Hemorrhage subsides after the sutures are placed. If the nostril does not appear adequately open, remove the sutures and excise more tissue from the either the lateral or medial aspect of the alar fold. Try to achieve symmetrical openings to the nostrils. (Figs. 5,6)
Fig. 5: Completed correction of one side of stenotic nares in a Shih Tzu
Fig. 6: Completion of both sides of correction of stenotic nares via wedge excision.
Postoperatively, keep the nostrils clean with moist sponges, and prevent self-mutilation with an Elizabethan collar if necessary.  Suture removal is not necessary since absorbable suture material is used.