4 Common Mistakes Made When Using Surgical Instruments

One of the most fundamental of surgical skills is proper handling of instruments. Using surgical instruments improperly can make the surgical procedure more difficult and time consuming. Here are 4 mistakes commonly made by inexperienced surgeons, and how to fix them:

1. Needle holders: the instrument is held with the thumb and 4th finger, but there is a right and wrong way to do it (it's all in the thumb!) This also applies to any forceps or scissors with ringed handles. (Fig. 1)

Fig 1a: Incorrect method to hold needle holders or any forceps or scissors
with ringed handles. Note how the thumb is too far inside the ring.

Fig 1b: Correct method to hold needle holders. Note that the only the tip
of the thumb is inserted through the ring of the instrument.

2. Thumb forceps: how the forceps are held can make a world of difference. (Figure 2)

Fig 2a: Incorrect method for holding thumb tissue forceps. This is a
clumsy grip that results in greater tissue trauma. 

Fig 2b: Correct and more precise method for holding tissue forceps. 

3. Retractors: holding them properly will avoid having the assistant's hand obscure the surgical field. (Fig. 3)

Fig. 3a: These are Senn retractors, commonly used in veterinary surgery.

Fig. 3b: Incorrect grip on the retractor. The fingers are too close  to
the end of the retractor resulting in the fingers and hand interfering with
the surgical exposure.

Fig. 3c: Correct grip on the retractor which will keep the fingers away from the
surgical field.

4. Cutting suture ends after tying a knot: here's a hint, use the tips! (Fig. 4)

Fig. 4a: Incorrect method of cutting suture ends with  scissors.
The blades close to the hinge are being used to cut the suture which
obscures the knot, making it difficult to see how long the suture ends will be. 

Figure 4b: Correct method; using the scissor's tips allow the assistant
to see the distance between the knot and the length being cut.

I hope you find these suggestions helpful. Post any questions or comments you may have on instrument handling and technique.

How To Repair Diaphragmatic Hernias in Dogs and Cats

 
   Introduction  
   Hernias of the diaphragm can be either congenital or acquired. Acquired hernias are most commonly due to blunt trauma to the abdomen.  Increased intra-abdominal pressure causes the diaphragm to stretch and rupture.  Liver, spleen and intestines are the organs most commonly herniated into the thoracic cavity.(1)  The muscular portion of the diaphragm, at its ventral and lateral aspects, is the most frequently torn area. Congenital hernias include the pericardial peritoneal diaphragmatic hernia (PPDH).

   Clinical Signs  
   Signs of respiratory distress, e.g., tachypnea, dyspnea, or abdominal breathing, are most common.  The animal may have a "tucked-up" appearance to the abdomen due to shifting of viscera into the pleural space.  In chronic cases, weight loss and lethargy may be the only signs the owners describe.(2) Exercise intolerance is also usually seen. In rare cases, the owner may describe signs referable to other organ systems.  For example, herniation of the intestine can cause obstruction of bowel, resulting in vomiting.  Herniation of the liver and biliary system can cause extrahepatic biliary obstruction, causing elevated serum bilirubin and icterus. 
   
   Diagnosis 
   Auscultation of the thorax reveals decreased lung sounds ventrally, and muffled heart sounds.  The thorax is dull on percussion.  Reportedly, auscultation of borborygmus in the thorax is a sign of diaphragmatic hernia, but this is not a consistent finding and should not be depended upon to make the diagnosis.
   Radiographic examination of the thorax may reveal fluid densities and/or bowel loops in the thorax. (Fig 1) Loss of continuity of the diaphragm is also seen. 

Fig. 1: Lateral thoracic radiograph of a dog with a diaphragmatic hernia and
several loops of bowel in the thoracic cavity. 

Hydrothorax may be the only radiographic sign if the liver is the only organ herniated into the thorax.  This fluid appears serosanguineous and is a transudate or modified transudate.  Ultrasonographic examination of the cranial abdomen can help confirm the hernia. 
   
   Preoperative Care  
   Diaphragmatic herniorraphy is usually considered an emergency operation. Although historically some authors advocated delaying surgical repair for several hours (3), a more recent study found that patients operated within the first 24 hours after presentation had very good outcomes (90% survival) (4). If the animal with diaphragmatic hernia does not stabilize with initial supportive care or if stomach or strangulated bowel is in the thorax the repair must be done immediately.(5) Stomach in the thorax can become dilated with air and cause life threatening hypoventilation. (Fig. 2) 

Fig. 2: Lateral thoracic radiograph of a dog with diaphragmatic hernia and stomach in the thorax cavity.
The stomach is severely dilated with air. 

If this occurs, pass a stomach tube to initially decompress the stomach If a stomach tube cannot be passed perform gastrocentesis percutaneously by placing a needle or over the needle catheter into the stomach through the chest wall.  When respiratory parameters have improved, anesthesia and surgery can then be performed.
   
   Anesthesia  
   Since these patients have markedly reduced ventilatory capacity, anesthetic induction and intubation must be rapid and smooth.  Pre-oxygenation of the patient in an oxygen cage or with an anesthetic mask is helpful to prevent hypoxia during the stress of anesthetic induction.  Rapidly acting intravenous induction agents, such as propofol, allow prompt intubation.  Begin positive pressure ventilation as soon as the endotracheal tube is placed.  Inhalant anesthetics, such as isoflurane, are acceptable for maintenance of anesthesia.
   During the clipping and prepping of the animal for surgery, the prep table can be tilted so that the head is elevated and the hindquarters lowered.  This helps prevent movement of abdominal viscera into the thorax.  
    
   Key Point: It is important to realize that when the abdominal cavity is surgically opened in an animal with diaphragmatic hernia, the animal will no longer be able to ventilate on its own. The rent in the diaphragm allows air to enter the thoracic cavity when the abdomen is open, eliminating the negative intrathoracic pressure that is necessary for normal ventilation. Intermittent positive pressure ventilation (IPPV) is therefore necessary during the surgical repair of the diaphragm. 
   
   Surgery 
   The ventral midline abdominal approach is indicated for most diaphragmatic hernias. (Fig. 3) 

Fig. 3: Intraoperative appearance of a left diaphragmatic hernia
exposed via a ventral midline abdominal approach.
(arrows indicate edges of the ruptured diaphragm).
The liver is present in the thoracic cavity.

Balfour retractors and large malleable retractors facilitate the exposure.  Grasping the edges of the diaphramatic defect with Babcock forceps or stay sutures can help in closure of the defect.  In many cases, the diaphragmatic defect must be enlarged to allow the viscera to be pulled back (reduced) into the abdomen.  When enlarging the defect, be sure to make the diaphragmatic incision in an accessible portion of the diaphragm to simplify closure. Chronic hernias may be associated with adhesions between the herniated organs and the lungs or mediastinum.(2) Break these down carefully to avoid injury to lung or other organs.  After reducing herniated organs back to the abdominal cavity carefully examine the lungs for evidence of atelectasis.  If atelectasis is found it is best not to acutely re-expand those lung lobes since re-expansion pulmonary edema can occur.  This is especially true in chronic hernias.  Place a thoracic drain tube before closure of the diaphragm to allow for re-establishment of negative pressure in the pleural space once the diaphragmic rent is repaired.  
   A variety of techniques for herniorrhaphy have been described.  The author prefers a continuous suture pattern using 2-0 or 3-0 PDS depending on patient size. Suturing is begun at the most inaccessible area of the defect (usually the dorsal aspect) progressing to the most accessible.(Fig 4) 

Fig. 4: Same dog as in figure 3 after suture closure of the diaphragmatic hernia.

Be very careful when working around the central part of the diaphragm because of the caudal vena cava.  Take care to not make the closure too tight around the caval hiatus.  Incorporation of the ribs with the soft tissues during suturing is sometimes necessary for those hernias that occur along the costal arch.
   In rare cases there is not enough diaphragmatic tissue to permit primary closure.  For example, chronic hernias in which the diaphragmatic tissue tears directly off the costal arch or dorsally from the spine.  In these cases reconstruction of the defect with a mesh implant such as Marlex mesh can be used.  The mesh is sutured in place with non-absorbable sutures such as monofilament polypropylene.  Prophylactic antibiotics are indicated in these cases.
   Once closure of the diaphragm is completed, remove residual air from the thorax.  This can be done either directly through the diaphragm using a needle or over the needle catheter or by placing a thoracostomy tube. When postoperative pneumothorax is a potential problem, such as those cases with lung adhesions, an indwelling thoracic drain tube should be placed and left in for as long as necessary to ensure stable negative intrapleural pressure. As previously mentioned in animals with chronic hernias and lung atelectasis, slowly evacuate the air in the pleural space over several hours to prevent re-expansion pulmonary edema. 
   
   Postoperative Care 
   Close observation of the patient is mandatory postoperatively.  If available the patient is kept in an oxygen cage until recovered.  In most cases recovery is unremarkable.  Acute, severe pulmonary edema can occur in some animals postoperatively and must be treated aggressively using diuretics, oxygen, and assisted ventilation.  In general the prognosis for postoperative survival is very good for patients with either acute or chronic diaphragmatic hernias. (2,4)
   
   References
1. Wilson GP, Newton CD, Burt JK. A review of 116 diaphragmatic hernias in dogs and cats. J Am Vet Med Assoc 1971; 159:1142-1145
2. Minihan AC, Berg J, Evans KL. Chronic diaphragmatic hernia in 34 dogs and 16 cats.
J Am Anim Hosp Assoc. 2004 Jan-Feb;40(1):51-63. 
3. Boudrieau RJ: Pathophysiology of Traumatic Diaphragmatic Hernia, in Bojrab MJ (ED): Disease Mechanisms in  Small Animal Surgery, ed 2. Philadelphia, Lea & Febiger, 1993, pgs 103–108
4. Gibson TW1, Brisson BA, Sears W. Perioperative survival rates after surgery for diaphragmatic hernia in dogs and cats: 92 cases (1990-2002).J Am Vet Med Assoc. 2005 Jul 1;227(1):105-9.
5.Bjorling DE. Thoracic Trauma, in Birchard SJ, Sherding RG, ed. Saunders Manual of Small Animal Practice. St. Louis, Elsevier, 2006, pgs. 1721-1722.

How To Safely Place a Chest Tube in Dogs and Cats

Indications

Thoracic drain tubes are indicated for animals with disorders of the thoracic cavity  that cause accumulation of air or fluid in the pleural space. Some examples are: pneumothorax due to trauma or spontaneous causes such as emphysematous bullae, or pleural effusion due to infection (pyothorax) or neoplasia. If repeated drainage of the thorax is anticipated for palliative care of the patient, a thoracic drain is more effective and less painful for the patient than repeated thoracocentesis with a needle or catheter. A properly performed thoracic drain tube placement is a safe and effective means of managing patients with acute or chronic pleural disorders.

Technique

Equipment
Basic surgical pack
Red rubber catheters (8 – 20 Fr),
or Argyle catheters with trocar (same sizes)
3-way stopcocks
Christmas tree adapters
Syringes (12 – 60mls)
Bandage materials
Antibiotic ointment
Suture material  (2-0 or 3-0 monofilament non-absorbable)

Place the animal under general anesthesia and prepare the lateral thorax for aseptic surgery. Make a small (2-3 cm) skin incision at the 10th intercostal space.
Incise through the subcutaneous tissue and the lattisimus dorsi muscle. Use a Carmalt or Pean forcep to create a tunnel underneath the lattisimus dorsi muscle from the skin incision to the 8th intercostal space. Grasp the tip of a red rubber catheter with a Carmalt forcep or use an Argyle trocar catheter. (Fig. 1)

Fig 1: The end of a red rubber catheter is grasped within a Carmalt clamp
from: Bateman SW, et.al. Emergency and Critical Care Techniques and Nutrition. 
In: Saunders Manual of Small Animal Practice. 3rd edition, 
Birchard and Sherding, eds., Elsevier, St. Louis, 2006. Pg. 29

Insert the tip of the tube into the skin incision and advance it through the tissue tunnel to the level of the 8th intercostal space.(Fig 2)

Fig. 2: The red rubber tube and Carmalt clamp are advanced from the 10th to the 8th intercostal space

Firmly grasp the tube and insert through the chest wall with a forceful but controlled effort. (Fig. 3)

Fig. 3: Cross sectional view of Carmalt clamp and chest tube entering the pleural cavity through the  intercostal space.
from: Bateman SW, et.al. Emergency and Critical Care Techniques and Nutrition. In: Saunders Manual of Small Animal Practice. 3rd edition, Birchard and Sherding, eds., Elsevier, St. Louis, 2006. Pg. 29

Once the tube has penetrated the chest wall, advance it into the pleural space. If using the Argyle tube, slide the trocar out of the tube and then slide the tube inside the pleural cavity.(Fig. 4)

Fig. 4: Sequence of steps(A-D) for inserting an Argyle thoracic drain tube with inner trocar into the chest cavity.
from: Crisp MS, Buffington CA. Critical Care Techniques. In: Saunders Manual of Small Animal Practice. 2nd edition, Birchard and Sherding, eds., Elsevier, St. Louis, 2000, pg. 21.

If using a red rubber catheter and forceps, after entering the chest open the forceps, slide the catheter into the pleural cavity, then remove the forceps from the incision. Promptly place a clamp on the tube after entering the chest to prevent pneumonthorax.

Place a 3-way stopcock on the end of the tube(Fig. 5); a Christmas tree adapter may be necessary to fit the stopcock to the flared end of the tube. 

Fig. 5: Stopcock secured to the end of the chest tube with wire; heavy
suture can also be used.

Use large suture or wire to secure the stopcock and adapter to the tube and place a purse string and finger trap pattern suture to secure the tube to the skin (Fig. 6).   

Fig. 6: Secure the thoracic drain tube to the skin with a purse string /finger trap suture combination.

A “C” clamp can also be placed on the tube for added safety in case the stopcock should become dislodged.  Apply antibiotic ointment to the tube entry site in the skin and protect the tube on the patient with a bandage.

Postoperative Care

Obtain radiographs of the thorax to ensure correct placement of the tube.(Fig. 7)

Fig. 7: Lateral thoracic radiograph of a cat with a thoracic drain tube in place.

Patients with thoracic drain tubes require 24 hour monitoring. If the tube becomes damaged or the stopcock is dislodged, immediate pneumothorax will occur and could be life threatening. Change the chest bandage as needed and check the tube location to be sure it is not pulling out and that the stopcock and Christmas tree adapter are tight and not leaking. Place an Elizabethan collar on the animal if necessary.

Evacuation of air and/or fluid can be performed either manually or with a continuous suction device which, when connected to a source of negative pressure, allows for drainage of the thoracic cavity. In most animals intermittent manual drainage of the chest cavity is sufficient to keep the animal’s respiratory status stable. 

In some cases a sudden increase in the amount of air being pulled from the drain tube can be due to a leak in the tube or its apparatus. Test the integrity of the tube by clamping the tube close to the patient and try applying negative pressure to the stopcock with a syringe. If air is easily withdrawn, a leak is present. Check all connections for tightness and check the tube for cracks or holes allowing air to leak into the system.

In addition to other routine supportive care measures, analgesic therapy with a NSAID or opioid such as Tramadol is indicated due to the painful nature of the indwelling tube in the pleural space. The pleura is one of the most sensitive tissues in the body and the tube acts as a foreign body rubbing on the pleural membranes. 

Thoracic drain tubes can be left in the patient for several days or even a few weeks at a time depending on the need for continued drainage. Since dogs do not have a complete mediastinum, a unilateral tube is usually adequate for drainage of both sides of the pleural cavity. However in some cases, such as chronic pyothorax or chylothorax, fibrinous adhesions in the cavity can make the fluid loculated, decreasing the function of the tube. Bilateral tubes may then be necessary.

Remove the chest tube when the amount of fluid or air is minimal. The chest tube acts as a foreign body in the pleural space and can create 1-2 mls/kg/24 hours of fluid. After removal of the tube apply antiobiotic ointment to the skin incision and keep the incision covered with a bandage for another 1-2 days.

The following is a video produced by my colleague Dr. Ron Bright demonstrating chest tube placement on a cadaver dog using an Argyle thoracic drain tube with trocar.

References

Bateman SW, et.al. Emergency and Critical Care Techniques and Nutrition. In: Saunders Manual of Small Animal Practice. 3rd edition, Birchard and Sherding, eds., Elsevier, St. Louis, 2006. Pg. 29

Surgical Removal of Screw Tail in Bulldogs

Case Report
Tank is a 7 year old male castrated English bulldog that presented for chronic skin fold dermatitis secondary to screw tail conformation.(Fig.1) 

Fig. 1: Tank, a 7 year old male castrated English Bulldog

The dog was showing signs of pruritis and pain in the tail area for several months. Physical examination revealed patchy partial alopecia of the lateral trunk and evidence of pyoderma in the skin folds associated with an ingrown tail.(Fig.2)

Fig. 2: The tail on Tank showing the typical screw  tail conformation

Preoperative thoracic radiographs showed no significant abnormalities. A radiograph of the caudal spine showed a typical abnormal tail anatomy common in bulldogs.
(Fig. 3) 

Fig. 3: Lateral radiograph of the caudal vertebrae on Tank showing the
abnormal coccygeal vertebrae. (arrow)

Pre-anesthetic CBC and serum chemistry profile on Tank were within normal limits. 

Surgical Procedure
Under general anesthesia, Tank was placed in sternal recumbency and the tail and adjacent skin was clipped and prepared for aseptic surgery. The anal sacs were expressed and a purse string suture was placed in the anus to prevent fecal contamination of the surgical site. Intravenous cephazolin was administered as a prophylactic antibiotic. 

The surgery was begun by making a cranial to caudal incision dorsally over the base of the tail.(Fig. 4) 

Fig. 4: The caudectomy on Tank began with an incision over the  dorsal aspect of the tail.

The tissues were dissected down to the bone by blunt and sharp dissection. After the soft tissues were dissected off, the coccygeal vertebrae were severed with a bone cutter and rongeurs.(Fig. 5)

Fig. 5: Appearance of surgical site after severing the coccygeal vertebrae. Arrow
indicates the cut edge of the vertebrae on the portion of tail to be removed.

The tail was then removed by extending the skin incisions ventrally on each side until the tail was no longer attached to the body.(Fig. 6)

Fig. 6: Surgical site after complete removal of the tail. Note the  cut
edge of the coccygeal vertebrae on the body (white arrow), and cut
edge of the coccygeal vertebrae on the excised tail (black arrow).

Care was taken not to injure the rectum which is just ventral to the tail. A Jackson-Pratt closed suction drain was placed in the deep aspect of the incision prior to closure. For more information on Jackson Pratt drains see: https://drstephenbirchard.blogspot.com/2014/03/jackson-pratt-drains-for-wounds-in-dog.html Excess skin was removed, and the surgical wound was closed in several layers: deep tissues with 2-0 PDS simple interrupted, subcutaneous tissues with 3-0 Monocryl simple interrupted, and the skin with 3-0 Monocryl simple interrupted. The purse string suture was removed. (Fig. 7)

Completed caudectomy on Tank including placement of the Jackson-Pratt drain.

Postoperatively Tank was given supportive care consisting of intravenous fluids, analgesic therapy, incision care and drain maintenance. Tank was discharged from the hospital the following day. Tank’s drain was removed 3 days postoperatively, and examination by the referring veterinarian 10 days postoperatively found satisfactory healing of the incision and improvement of his clinical signs. A follow-up phone call to the owner 1 month after surgery found Tank to continue doing well with no further pruritis or evidence of infection in the tail area.

Discussion
Intertriginous dermatoses, or skin fold pyoderma, is a well recognized disorder caused by excessive skin folds in various regions in dogs, such as nasal, lip, perivulvular, and the secondary to the screw-tail, or ingrown tail abnormality in bulldogs. Redundant skin in these areas leads to skin friction, excessive moisture, and poor air circulation. Trapped skin secretions are fertile ground for surface bacteria and yeast to establish infection. 

Medical treatment consisting of hair clipping, medicated soaps and shampoos, and topical and systemic antibiotics may improve the condition, but surgical resection of the excessive skin is necessary to achieve successful long-term resolution. In bulldogs with ingrown tail, amputation of the tail is the most effective method of treating this form of intertriginous dermatoses. However, detailed descriptions of the technique for removal of the very abnormal bulldog tail are not widely available in the veterinary literature. 

Postoperative complications after caudectomy for ingrown tail were analyzed in one clinical study of 17 dogs. (1) Short-term complications were rare but included postoperative wound infection and changes in defecation behavior. Long-term complications were not seen and the authors stated that the procedure effectively resolved clinical signs in the dogs studied. 

References
1. Knight SM1, Radlinsky MG, Cornell KK, Schmiedt CW. Postoperative complications associated with caudectomy in brachycephalic dogs with ingrown tails. J Am Anim Hosp Assoc. 2013 Jul-Aug;49(4):237-42. 

Acute Traumatic Abdominal Hernia in Dogs and Cats

Case Report

Cass is a 2 year old spayed female who presented to the emergency service after been bitten by another dog. She had no pertinent history of other health problems. On physical examination Cass had a palpable soft tissue subcutaneous swelling on the left lateral abdomen. A defect in the abdominal wall was palpable deep to the swelling and viscera were thought to be in the subcutaneous space. 

Plain radiographs of the abdomen revealed a left lateral abdominal hernia. (Fig. 1) No other radiographic abnormalities were found. 

Fig. 1: Ventrodorsal radiograph of Cass confirming left lateral abdominal hernia (arrow).

Cass was initially treated with supportive care consisting of intravenous fluids with a balanced electrolyte solution, analgesics, and antibiotics. Preoperative CBC and serum chemistry profile were within normal limits. Cass was placed under general anesthesia and the ventral abdomen was clipped and prepared for aseptic surgery. (Fig. 2) 

Fig. 2: Cass in dorsal recumbency after clipping and prepping for  abdominal surgery.
Note the bulge on the left lateral abdomen at the site of the hernia.

A ventral midline abdominal approach was made. On thorough exploratory of all abdominal structures herniation of a portion of jejunum was found in a left sided abdominal wall defect.(Fig. 3, 4) 

Fig. 3: Intraoperative view of the abdominal cavity on Cass. (Head is to the left.)
Note herniated bowel and omentum (arrow).

Fig. 4: Same intraoperative view as figure 3 after reduction of the hernia showing the muscular defect.

Gentle traction on the herniated bowel reduced the hernia and the bowel mesentery was bruised but all tissues were viable. The abdominal muscle defect was closed from within the abdominal cavity with 2-0 PDS simple continuous pattern.(Fig. 5) 

Fig. 5: Same intraoperative view as figures 3 and 4 showing closure of the hernia.

The ventral abdominal incision was closed routinely. 

Postoperatively supportive care (IV fluids, analgesics, and antibiotics) was continued. Cass made an uneventful recovery and was discharged the day after surgery. At suture removal 10 days postoperatively Cass was doing well.

Discussion

In animals with severe abdominal trauma, hernias can be missed on initial physical examination. Serial, thorough physical examinations and careful analysis of abdominal imaging is recommended to fully assess trauma patients. Intestine and omentum were the 2 most commonly herniated structures in the study previously mentioned. (1)

Bite wounds were the most common cause of traumatic abdominal hernias in one study, with vehicular trauma being the next most common cause. (1) This is in contrast to an older study that found blunt trauma to be the primary cause of traumatic hernias.(2) Additional injuries, such as bowel perforation, are common complications of abdominal hernias. 

Key Point: Dogs and cats with acute traumatic abdominal hernias should have a complete abdominal exploratory via routine ventral approach. The hernias can be repaired from within the peritoneal cavity by closing the affected interior muscle layers. (3)

References
1. Shaw, Scott P; Rozanski, Elizabeth A; Rush, John E. Traumatic body wall herniation in 36 dogs and cats. JAAHA 39:35-45 2003.
2. Waldron DR, Hedlung CS, Pechman R. Abdominal hernias in dogs and cats: a review of 24 cases. JAAHA, 22:817-822,1986 
3. Smeak, DD. Abdominal wall reconstruction and hernias. In: Veterinary Surgery Small Animal, eds. Tobias KM, Johnston, SA. Elsevier, St. Louis, pg. 1368.

When Is Umbilical Hernia in Dogs An Emergency Operation? Here's a Great Example

Case Report

A 7-year-old spayed female mixed breed dog named Lola presented with acute vomiting and rapid enlargement of a mass over her umbilicus.(Fig.1) 

Fig. 1: Lola, a 7 year old female spayed dog

The owners reported that she had a hernia there since birth but it just recently got much larger. The mass was soft, painful on palpation, and not reducible. An umbilical hernia containing abdominal viscera was suspected.

Plain film abdominal radiographs were obtained and confirmed an umbilical hernia with loops of intestine in the hernia sac. (Fig.2)  The remainder of the abdomen was radiographically within normal limits. 

Fig. 2: Lateral abdominal radiograph in Lola showing
an umbilical hernia with incarcerated bowel (arrow)

Complete blood count and serum chemistry profile were unremarkable. An intravenous catheter was placed and a balanced electrolyte solution administered to correct dehydration. Under general anesthesia the ventral abdomen was clipped and prepared for aseptic surgery. (Fig.3) 

Fig. 3: Appearance of the hernia in Lola after clipping for surgical repair

A ventral abdominal approach was performed with care taken to not injure structures within the hernia. A strangulated loop of jejunum was found in the hernia. (Fig.4) The remainder of the abdomen was normal. 

Fig. 4: Intraoperative photo of Lola during abdominal exploratory showing the
strangulated portion of jejunum after it was reduced.

The affected segment of intestine was resected and an end to end anastomosis performed (see http://drstephenbirchard.blogspot.com/2013/10/intestinal-anastomosis-made-simple.html for details on technique for intestinal anastomosis).  Debridement of the tissue edges of the hernia was not necessary and it was repaired as part of the routine linea alba closure with 2-0 PDS, simple continuous pattern. The remainder of the abdominal incision was closed routinely. Postoperative abdominal radiographs confirmed satisfactory closure of the hernia. (Fig. 5) 

Fig. 5: Lateral abdominal radiograph of Lola 1 day after repair of the umbilical hernia.

Lola recovered well from surgery and was released from the hospital 2 days postoperatively.

Discussion

Lola is an example of a dog with an incarcerated (non-reducible), and strangulated (loss of blood supply of the hernia contents) umbilical hernia. Umbilical hernias are common in dogs and cats but rarely do they contain intestine or other abdominal organs.(1) More commonly umbilical hernias are small and contain a portion of the falciform ligament or greater omentum. 

Plain film radiographs were diagnostic for the hernia in Lola. Ultrasonography can also be useful to determine if a hernia is present and if organs are located in the hernia sac. 

The clinical signs of acute vomiting and pain on palpation were suggestive of intestinal obstruction, and possibly strangulation. Vomiting was predictive of non-viable intestine in inguinal hernias in dogs in one study.(2) Emergency surgery is indicated when this type of hernia is suspected. 

In Lola the hernia repair was straightforward since adequate local tissues, i.e. rectus muscle fascia, was available for closure without tension across the suture line. Larger defects may require a muscle flap or mesh implant, such as polypropylene mesh, for effective repair. Mesh is well tolerated in dogs and provides a strong and stable closure for abdominal wall defects with minimal complications.(3)

Complications of hernia repair include pain, seroma, infection, reoccurrence and mesh rejection requiring removal.   However, complications are rare and the prognosis for successful repair of congenital and traumatic hernias is generally good. 

This is the first in a series of Veterinary Key Points blogs addressing congenital and acquired hernias in dogs and cats. Watch for future articles on other hernia types and their treatment.

References

1. Ruble RP, Hird DW. Congenital abnormalities in immature dogs from a pet store: 253 cases (1987-1988). J Am Vet Med Assoc. 202(4) 633-636, 1993

2. Water DJ, Roy RG , Stone EA. A retrospective study of inguinal hernia in 35 dogs. Vet Surg 22:44, 1993

3. Bowman K, Birchard SJ, Bright RM. Complications associated with implantation of polypropylene mesh in dogs and cats: A retrospective study of 21 cases (1984-1996). J Am An Hosp Assoc 34:225-233, 1998

Episioplasty for Perivulvular Dermatitis in Dogs

Intertriginous dermatoses, or skin fold pyoderma, is a well recognized disorder caused by excessive skin folds in various regions in dogs, such as nasal, lip, and perivulvular skin folds.(Fig. 1a,b)

Fig. 1a: Excessive skin fold in perivulvular area of a  spayed mixed breed dog.

Fig. 1b: Same dog as Fig. 1a; the chronically inflamed vulva is exposed by
pushing the skin fold dorsally.

Redundant skin in these areas leads to skin friction, excessive moisture, and poor air circulation.(1a-b) Trapped skin secretions are fertile ground for surface bacteria and yeast to establish infection. Chronic skin infection in the perivulvular region can also lead to ascending urinary tract infection(UTI). 

Medical treatment consisting of hair clipping, medicated soaps and shampoos, and topical and systemic antibiotics may improve the condition, but surgical resection of the excessive skin is necessary to achieve successful long-term resolution.(1) Episioplasty is a skin reconstructive surgical procedure to correct excessive perivulvular skin folds and is well described in standard surgical textbooks.(Fig.2)

Fig. 2: Schematic representation of episioplasty in dogs. A: initial incision of skin to be resected;
B: beginning skin closure; C: completed closure.
From: Bellah JR. Surgery of intertriginous dermatoses. In: Saunders Manual of Small Animal Practice. 3rd edition, 
Birchard and Sherding, eds., Elsevier, St. Louis, 2006. Pg. 537

Episioplasty has been used for many years to treat perivululvar dermatitis in dogs that did not respond to more conservative treatment but has also been shown to be an effective treatment for the chronic urinary tract infection associated with perivulvular dermatitis.(2) In this blog we will describe the surgical technique and postoperative care for episioplasty in dogs. 

Surgery 
After placing the dog under general anesthesia, it is positioned in ventral recumbency and the perivulvular region clipped and prepared for aseptic surgery. Administer prophylactic intravenous antibiotics, such as cefazolin, to establish blood levels prior to the surgical procedure. Empty the anal sacs and place a purse string suture in the anus to prevent fecal contamination during the perioperative period. Pull the tail dorsally and cranially and secure with tape. 

The redundant perivulvular skin is carefully examined to determine how much will require resection. The proposed area of skin to be removed is marked to aid in excision.(Fig.3) 

Fig. 3: The proposed area of perivulvular skin to be resected is marked with a sterile marking pen.

The skin incisions are made with a scalpel and the skin removed with blunt and sharp dissection using Metzenbaum scissors.(Fig.4) 

Fig 4: Appearance of the surgical site after resection of the perivulvular skin fold..

Electrocautery is used for hemostasis. Only the skin is removed; subcutaneous fat is left in tact in order not to create excessive dead space under the reconstructed skin. The deep fascia and subcutaneous tissues are closed first with absorbable suture in a simple interrupted pattern. The first sutures are placed at the 10, 12 and 2 o’clock positions, then the remainder placed as needed to provide accurate apposition of the skin.(Fig.1) Skin closure can be with skin sutures, intradermal sutures, or continuous absorbable skin suture (e.g. 4-0 Monocryl).(Fig.5)

Fig. 5: Appearance of the surgical site after completion of  the skin closeure.

Remove the pursestring suture in the anus after completion of the procedure. 

Postoperative Care 
Postoperative care consists of analgesic therapy such as tramadol and a NSAID (if not contraindicated), ice packs on the incision for the first 24 hours followed by warm compresses, and exercise restriction until the incision is healed and skin sutures removed.(Fig.6) 

Fig 6: Appearance of the surgical site 3 weeks postoperatively.

Keep the incision clean and free of urine and fecal soiling. If episioplasty was performed for chronic UTI, maintain antibiotic therapy for 2-3 weeks followed by repeat urine culture and sensitivity. Continue antibiotics until the urine culture is negative. 

Prognosis 
Complete resolution of the skin fold pyoderma should occur after resection of the excessive skin. Episioplasty is effective in treating perivulvar dermatitis.and in treating chronic urinary tract infection that is secondary to ascending infection from excessive skin folds around the vulva.(2) 

References 
1. Bellah JR. Surgery of intertriginous dermatoses. In: Saunders Manual of Small Animal Practice. 3rd edition, Birchard and Sherding, eds., Elsevier, St. Louis, 2006. Pg. 537. 
2. Lightner BA, McLoughlin MA, Chew DJ, Beardsley SM, Matthews HK. Episioplasty for the treatment of perivulvar dermatitis or recurrent urinary tract infections in dogs with excessive perivulvular skin folds: 31 cases (1983-2000). J Am Vet Med Assoc 219: 1577-1581, 2001

Splenectomy in Dogs and Cats: Indications, Surgical Technique, and Postoperative Care

Splenectomy is the partial or total removal of the spleen. Common indications for splenectomy include splenic neoplasia, severe splenic trauma and splenic torsion.
(Fig 1)

Fig. 1: Abdominal exploratory revealing a very large splenic hematoma in a golden retriever.
The tumor and spleen were surgically removed.

 Thrombosis of the spleen can also occur, sometimes associated with gastric dilatation/volvulus, and also requires splenectomy. (Fig 2 )

Fig. 2: Thrombosis of part of the spleen in a dog. (normal spleen white arrow,
thrombotic spleen black arrow) Note sharp demarcation between the normal and
abnormal portions of spleen.

Preoperative Considerations

History and Physical Examination– Animals requiring splenectomy can present with a variety of clinical signs depending on the disorder. Acute onset of pale mucous membranes, collapse and hemoabdomen are common findings in animals with splenic neoplasia, especially hemangiosarcoma. For splenic fracture, there is usually a recent history of blunt or penetrating trauma. Animals with splenic rupture will have hemoabdomen and develop pale mucous membranes, collapse, tachycardia, tachypnea, and evidence of fluid on abdominal palpation. Abdominal palpation may also reveal abdominal discomfort or a cranial abdominal mass.

Diagnostic Evaluation – A complete blood count (including platelet count), biochemical profile and urinalysis are indicated in animals with suspected splenic disease. Assessment of coagulation may also be indicated, especially in dogs with suspected hemangiosarcoma since disseminated intravascular coagulation can occur with that neoplasm. Arterial blood pressure is performed to detect hypotension. Abdominal radiographs or ultrasonography may discover fluid or a cranial abdominal mass. Ultrasonography may also reveal evidence of metastasis of the primary splenic tumor to other sites such as the liver and regional lymph nodes. If fluid is present, perform abdominocentesis, and evaluate the fluid packed cell volume, total protein and cytology. Obtain thoracic radiographs to examine for metastasis or other problems.

Initial Treatment – Prior to anesthesia and surgery, stabilize patients with intravenous fluids and blood transfusions if necessary. Although it may be impossible to return the animal to normal circulatory status prior to surgery, improvement of their condition is desirable to make them a better candidate for anesthesia and surgery.

Surgical Anatomy 

The spleen is located in the left cranial abdomen and lies parallel to the greater curvature of the stomach. The splenic artery is a branch of the celiac artery. Branches of the splenic artery also supply the left limb of the pancreas (pancreatic branch), the fundus of the stomach (short gastric arteries and veins), and the greater curvature of the stomach (left gastroepiploic artery and vein). (Fig 3) Many small branches arise from the terminal branches of the splenic artery and vein and enter the splenic parenchyma perpendicular to the long axis of the spleen. The splenic vein drains the spleen and transports blood into the gastrosplenic vein and ultimately to the portal vein.

Fig. 3: Surgical anatomy of the spleen. Arrows indicate the small vessels that
are dissected, ligated in small groups, and divided during total splenectomy.
(from: Evans HE, de Lahunta Miller's Anatomy of the Dog Saunders/Elsevier 4th ed.
Tobia and Johnston, Veterinary Surgery Small Animal Elsevier, 2012)

Surgical Technique

Perform a routine ventral abdominal approach from the xyphoid to a few centimeters cranial to the pubis. After a thorough exploratory of the abdomen, the spleen is exteriorized and isolated with moistened abdominal sponges. A partial or total splenectomy can be performed, depending on the reason for the splenectomy. Partial splenectomy will preserve splenic function, but total splenectomy is usually performed since it is technically easier and there are few long-term complications from total splenectomy in dogs and cats.

If one or more tumors are present on the spleen, omental adhesions may be present and should be ligated and sharply divided. Dissection and ligation of the small splenic vessels close to the hilus can then be done. These vessels can be ligated and divided in small groups when they are close together. Be careful to preserve the short gastric vessels that supply the gastric fundus, and the left gastroepiploic vessel that supplies blood to the greater curvature of the stomach. Also avoid ligating the pancreatic branch of the splenic artery. If the small vessels are ligated close to the splenic parenchyma, vessels to the pancreas and stomach will not be compromised.

Splenic vessels can be ligated with suture (e.g. Monocryl), hemostatic clips; the LDS  device (ligate, divide, staple), or the Ligasure vessel-sealing device (see video below). The author prefers the Ligasure for splenectomy since it is a rapid and effective means of providing hemostasis.

In animals with splenic torsion, the blood vessels to the spleen are twisted into a pedicle that contains the mesentery and vessels. Do not untwist the spleen since this will allow cellular breakdown products, thrombi, and other toxic substances to be released into circulation.(1) Ligate the entire vascular pedicle with full and transfixing ligatures and remove the spleen.

After removal of the spleen, check all ligated vessels for lack of persistent hemorrhage and then close the abdomen routinely.

Postoperative Care and Complications

Maintain supportive care immediately after surgery consisting of intravenous fluids, analgesics and monitoring of vital signs. If preoperative or intraoperative blood loss was excessive monitor the animal’s PCV postoperatively and consider blood transfusion if the PCV drops below 20. With appropriate care most dogs will recover from splenectomy quickly with many being discharged from the hospital the day after surgery.

The most common complication associated with splenectomy is hemorrhage. Other potential complications include pancreatitis, cardiac arrhythmias, and postoperative pain.

The prognosis for dogs undergoing splenectomy varies depending on the splenic disease. Dogs and cats with splenic trauma, splenic torsion, or benign neoplasia have a good prognosis assuming they survive the perioperative period. In contrast, animals with malignant neoplasia, most commonly hemangiosarcoma, have a poor prognosis due to the tendency for metastasis of the primary tumor.(2)

References

1. Richter MC. Spleen, in Veterinary Surgery: Small Animal, eds. KM Tobias, SA Johnston, Elsevier, St. Louis, 2012, pg. 1341.
2. Spangler WL1, Kass PH. Pathologic factors affecting postsplenectomy survival in dogs. J Vet Intern Med. 1997 May-Jun;11(3):166-71.