VSR 421: Regional Veterinary Surgery (2+1)

Diaphragmatic hernia in dogs

 DIAPHRAGMATIC HERNIA

• Congenital peritoneo pericardial hernia
• The signs occur at any age. sometimes will be shown while shifting to solid food.
• It is also noticed incidentally in thoracic radiographs or at necropsy.
• Clinical signs include respiratory distress and related to the type of organ involved in herniation.
• Acquired Diaphragmatic hernia
• Diaphragmatic hernia in dogs is usually traumatic; like accidents or a fall from a height. The hernial content is usually a portion of omentum, stomach or liver and very rarely intestine.
• The extent of herniation depends upon size and location of tear. The hernia gradually develops through a small tear due to negative pressure in the thoracic cavity and bellowing action of the abdomen during respiration. Weakest points in the diaphragm are
  • Close to posterior vena cava
  • Costal margin
  • Close to the oesophagus

Symptoms

• Symptoms in congenital diapragmatic hernia, may not be noticed until the pup attains six months of age and when its starts feeding on solid foods. 
• Abdominal breathing.
• Peculiar cough,  tendency to tire easily,  unthriftiness and tucked up abdomen.
• Tendency to vomit after feeding.
• Animal is reluctant to move.  Remains most of the time in standing position or sitting on the haunches.
• Difficulty and pain while walking down from a height.
• Chronic stomach disorders.
• Respiratory distress .
• Gurgling sounds on auscultation of chest. Absence of respiratory sounds on affected side. More pronounced respiratory distress immediately after feeding

Diagnosis

• History and clinical signs on auscultation – cardiac sounds are muffled
• plain/contrast radiography

Plain radiography - Diaphragmatic hernia

 

• Contrast x- ray Diaphragmatic hernia

Contrast radiography  showing intestines in the thorax

• Exploratory laparotomy 
• Ultra sound scan

Treatment

• The condition is corrected only by surgery. IPPV The diaphragm can be approached by different approaches
  • Abdominal approach
  • Lateral Thoracic approach
  • Median sternotomy
  • Rib splitting
  • The median sternotomy and rib splitting techniques are rarely used. Median sternototmy gives a very good exposure whereas the exposure to the thoracic cavity is very limited with rib splitting.
  • Intra operative considerations: In all the approaches the animal should be maintained under positive pressure ventilation.
  • Negative pressure in the thoracic cavity should be re established by aspirating the air from the thoracic cavity before the final closure.

Thoracic approach

• The thoracic cavity is entered through a 6th or 7th intercostal space. The hernia is reduced and the tear in the diaphragm is sutured with a 1/0 synthetic absorbable suture material.
• Care should be taken to avoid injury to lungs and other great vessels. The intercostal incision is closed including the adjacent ribs.

Abdominal approach

• Mid line incision starting from Xyphoid backwards is made.
• The hernia is reduced and the tear in the diaphragm is closed in the same manner.