Initial Approach

Team work is the essence and the name of the game dealing with Thorax trauma and every member of the emergency team needs to know and understand his assignment.

Main sources for Thorax Trauma in Dogs

 Hit by car

 Dog fights / bites

 High rise syndrome

 Mistreatment, kicks, punches and other type of blows

 Penetrating wounds (bullets, knives, etc.)

Main Sources for Trauma in Cats

 Fights / bites

 Mistreatment, kicks, punches and other type of blows

 Penetrating wounds (bullets, knives, etc.)

 High rise syndrome

 Hit by car

Blunt trauma can be related to car accidents, fall from a height or high rise syndrome, kicks or "human beings" interaction, penetrating trauma, bites or fight, specially small--large animal interactions, projectiles, stabbing.

In a patient with severe or multiple trauma initial assessment is made at the same time as other things are initiated to stabilize the patient. Fluid therapy and shock treatment are started at the same time the patient is being evaluated. Survey asking a detailed history of the trauma incident may provide vital clues.

Time lapse since the trauma occurred is an important information that has to be asked to the owners. Many times because of anxiety, the time lapse cannot be thoroughly determined, but whenever possible is a very useful data and can help with some actions to be taken.

Detailed inspection of the animal would reveal external or even internal injuries. Clipping the hair may facilitate visualization of bruises. Hypoxia and hemorrhage are two of the main causes of death among traumatized patients.

Every traumatized patient whom present in shock with no evidence of external bleeding, third space accumulation of blood must be assessed and ruled out.

The physical evaluation must be done in an orderly fashion, always keeping in mind the ABC concepts, no matter this subject has suffer modifications in the latest times: respiratory, cardiovascular, nervous, digestive, and muscle / skeletal systems.

 Inspection: Initial overall observation of the patient

 Palpation: Superficial and deep.

 Percussion: Free fluid? gas? pain?

 Thorax Auscultation: Decreased vesicular murmur, muffled or absent respiratory--heart sounds?

 Other: Draw blood for preliminary lab data: blood work and chemical panel, bladder catheterization: urine sample, rectal palpation: pain, fractures.

 Preliminary assessment: Rectal temperature, heart rate and respiratory rate, color of mucous membranes, capillary refill time and hydration status, pulse quality and rhythm, external bleeding assessment, skin integrity and lesions, level of consciousness (mentation).

 Respiratory system: Adequate ventilation, imbalance between ventilation and perfusion, upper airway disturbances, need tracheotomy? Pneumothorax? Think about thoracocentesis, diagnosis or therapeutic, trauma or lung injuries? Ruptured diaphragm? Hemo, hydro or chylothorax? Does any lesion require immediate surgery?

 Cardiovascular system: Any external visible hemorrhage? Any hypovolemic or shock signs, arterial blood pressure, pulse oxymetry, rhythm and pulse characteristics, cardiac auscultation, venous distention? IV catheter placement and open IV pathway, replace any volume deficiency, colloids requirements, does any lesion require immediate surgery?

 Nervous system: Level of consciousness? Alert, ambulates, reflexes, unconscious? Gait? Depressed, paretic, paraplegic? Has the patient received any medication that may alter the examination? Some pathological changes in the central or peripheral nervous system? Does any lesion require immediate surgery?

 Digestive system: Abdominal trauma can be a challenge to diagnose. 50% of serious lesions are misdiagnosed in human being patients!!!! It is highly important to keep in mind a suspicion for abdominal trauma every time we deal with traumatized patients. Any signs of acute hemorrhage? Ruptured spleen? Other hemorrhage sources like kidneys, liver, mesenteric vessels?: abdominocentesis / diagnostic peritoneal lavage (DPL) GI tract assessment. Abdominal viscera exploration (i.e., urinary bladder, ureters, gall bladder, pancreas): ultrasound scan, radiograph. Possible peritonitis? Need for immediate exploratory laparotomy?

 Muscle skeleton system: Gait abnormalities or lameness, any visible signs of open fracture or luxation? Joint exploration, tendon laceration or avulsion?

Ancillary Diagnostics

X-rays must be taken if possible before any centesis or DPL is performed since these procedures may introduce air / fluid into the abdominal cavity. Plain or contrast studies? Ultrasound? CT scan or MRI? Do we always need such expensive studies?

 Thorax: Assess and palpate for thoracic movement and respiratory pattern.

 Rib fractures. Do we need to pain treatment? Flail chest? Support bandages? Penetrating wounds. Locate heartbeat.

 Abdomen: Look for pain, evidence for free fluid or abdominal distention. Diagnostic peritoneal lavage more accurate (20ml/kg of warm saline or lactated Ringers), identify every palpable organ whenever possible, retroperitoneal space evaluation.

 Spine and appendages: Temperature of extremities, evaluate for fractures or luxations, check for wounds or any evident deformity, retroperitoneal space can be involved in spinal and / or pelvic fractures.

 Nervous system: Evaluate aptitude to stand up and walk, position of the extremities and presence of paresis / paralysis, flaccidity or rigidity, cranial and peripheral reflexes.

 Head and neck: Blood loss coming from the natural openings? Look after injuries in the head, eyes, ears, nose and nostrils, check for pain and range of motion of the head, open the mouth and explore it for tongue or dental lesions. Remember palate fractures in high rise syndrome. Airway obstruction due to saliva and blood clots?

Specific Thorax Approach

Maybe, the major decision in the approach of small animal patient with thoracic trauma, is to recognize the real need for surgical intervention, while most of thoracic injuries can be appropriately managed by simple measures aimed to correct hypoperfusion and hypoxemia. Emergency thoracotomy should be considered in every unstable patient who has the source of instability potentially corrected by surgery.

Tap it before Rad it: This is "almost always" rule. Most of the lesions should be diagnosed by needle thoracocentesis, instead of chest radiograph. A simple technique, a butterfly catheter, 10 cc syringe and 3-way lock. Cats with respiratory effort because thorax trauma needs a very gentle management, and normally they refuse adopt positions according radiology examination. Attempts to force them can cause the death of the cat.

Open pneumothorax: There is a free communication trough a chest wall between the pleural space and atmosphere. Can be life threatening according of the size of the wound. Patients came into clinic showing respiratory efforts and a rapid shallow restrictive respiratory pattern. Auscultation shows muffled thorax sounds: heart and respiratory. Diagnosis should made base on thoracocentesis and suction of variable amount of free air. Treatment involves the repair of the chest defect and place a drainage tube to keep the pleural space with negative pressure.

Close pneumothorax (tension pneumothorax): This lesion arise when a one way valve phenomenon on the lungs, allowing the air leak the lung space and increase the pressure and gas accumulation. Normally is a self limiting condition and just require supportive care like oxygen and fluid administration.

Diagnosis and initial treatment should be done by thoracocentesis and fine needle gas aspiration. Further treatment need chest tube placement and permanent gas suction system.

Hemothorax: Massive lesions are rare in dogs and cats compare with human beings. If the thoracocentesis reveals the presence of blood in a considerable volume, the patient should be treated as hypovolemic and fluid infusion using crystalloids, colloids or blood products.