Author

Stephen J. Birchard DVM, MS, Diplomate ACVS

Saturday, August 16, 2014

Scrotal Hematoma in Dogs After Castration: Why does it happen and how to prevent it.

Scrotal hematoma, the accumulation of blood in the scrotal sac, is a common postoperative complication of castration in dogs. (Fig. 1) 
Fig. 1: Scrotal hematoma that developed after castration in this golden retriever
Postoperative bleeding from one or both testicular arteries or veins is the most likely cause. Bleeding from these vessels can also accumulate in the abdominal cavity and be unrecognized until the dog becomes hypovolemic and develops shock. Bleeding from subcutaneous tissues could also result in a scrotal hematoma but is less likely, particularly in cases where bleeding is severe and the scrotal hematoma is large.

Etiology
Insecure ligatures are probably the cause of bleeding from testicular vessels. Ligature failure during castration may be due to a number of technical problems, such as loose ligature, improper suture material, or ligature slippage. Improper location of the suture ligature can also predispose to failure. If the spermatic cord is not adequately exteriorized the ligatures will be placed too close to the testicle. (Fig. 2) 
Fig. 2: The red dotted line indicates ligation of the spermatic cord too close to the testicle (T)
The ligatures in the figure are placed in the proper location.
(Modified from: Boothe, HW. Surgery of the testicles and scrotum. Saunders Manual of Small Animal Practice, Birchard and Sherding editors,  Figure 87-1, Elesevier, 2006, pg. 970.)
This causes excessive tissue to be incorporated in the ligatures. Insufficient stripping of the adipose tissue from the cord also predisposes the ligature to slippage.

Treatment
Scrotal hematomas can be managed medically with compresses (ice packs for the first 24 hours postoperatively, followed by warm compresses), Elizabethan collar, restricted exercise, analgesics such as NSAIDS, and antibiotics. In severe cases or those not responding to medical therapy, scrotal ablation is necessary to remove the entire scrotum and its contents.

Prevention
To prevent scrotal hematoma when performing castration, adhere to the following technical principles:
- After incising over the testicle and exposing it, break down the gubernaculum testis and place traction on the testicle to allow several centimeters of the spermatic cord to be exposed. (Fig. 3)
Fig. 3: Proper exposure and clamping of the spermatic cord during routine canine castration.
- Carefully and thoroughly strip the adipose tissue from the spermatic cord with a moistened surgical sponge.
- Triple clamp the cord with Carmalt clamps, cut between the 2 clamps closest to the testicle and perform routine ligatures with Monocryl or PDS suture (transfixing and full ligatures). The full ligature is placed in the crush area of the most proximal clamp after it is removed, the transfixing ligature is placed just distal to the full ligature. (Fig. 4)
Fig. 4: Proper ligature technique in a closed canine castration. (T=testicle)
(Modified from: Boothe, HW. Surgery of the testicles and scrotum. Saunders Manual of Small Animal Practice, Birchard and Sherding editors, Elesevier, 2006, Figure 87-1, pg. 970.)
- Check the vascular stump for bleeding prior to replacing it into the incision. Repeat the same procedure on the opposite side.  

I prefer closed castration, even on large dogs, because it allows excision of the testicular tunics along with the testicle. (Fig. 5)
Fig. 5: Closed castration allows removal of the parietal vaginal tunic with the testicle
Close the subcutaneous tissue routinely (3-0 or 4-0 absorbable suture in a simple continuous pattern). Although skin sutures can be used on the skin incision, I prefer do an intradermal closure in lieu of skin sutures. Fewer complications occur with an intradermal closure of castration incisions. In an unpublished study performed at Ohio State several years ago, dogs with intradermal skin closure had fewer incisional problems and even fewer scrotal hematomas postoperatively. Less self-trauma to the incision and scrotum were thought to be the reason for this finding.

What are your experiences and opinions regarding castration technique and complications in dogs? Do you have any tips or suggestions? Post questions and comments either on the blog or on facebook (Dr. Stephen Birchard, Veterinary Continuing Education) 

Thank you!