Penetrating abdominal trauma

Most penetrating abdominal trauma in New Zealand occurs from stab wounds. Gun-shot and other missile/projectile injuries present less frequently.¹

 

Penetrating abdominal trauma management algorithm 

Penetrating abdo flow chart with CT scan changes oct 2023

 

Management pearls

• In patients with upper abdominal stab wounds (or any GSW/projectile), haemodynamic instability may be due to pericardial injury or massive haemothorax/tension pneumothorax. Perform urgent FAST scan (and CXR)

 

• Upper abdominal wounds should be considered as junctional wounds and should have a CT chest and abdomen performed (provided the patient is stable and there are no indications for immediate laparotomy). Note that a normal CT may not rule out a diaphragmatic injury and further investigations (eg: laparoscopy) may need to be considered if this is suspected. 

 

• Intraabdominal injuries from stab wounds should be considered if the wound is from the nipples (T4) to the groin crease anteriorly, and from the tips of scapulae (T4) to the gluteal folds posteriorly.

 

• Gunshot wounds and projectiles are more likely to cause serious intraabdominal injury and can cause injuries or lodge quite distant from the entry wound
  • any entry wound on the torso could have a trajectory which could cause intra-thoracic injury.
  • The number of wounds + foreign bodies seen on AXR/CXR should be an even number (have a think about this!). If not you are
    • missing a wound
    • missing a bullet (expand imaging ie: image the neck, chest and abdo/pelvis)
    • or the patient has been shot before

 

• If a stab wound is thought to be superficial, careful exploration in the ED can be performed. If the wound base is clearly seen in the subcutaneous tissue with no violation of the abdominal rectus fascia, the wound can be irrigated and closed (and the patient discharged if clinically appropriate). Do not probe wounds blindly.

 

• If the patient has an anterior abdominal wound and a negative CT scan, the wound could be closed and the patient considered for discharge after discussion with the surgical team.

 

 

 

Mechanism of injury – history

 

Stab wounds

• Type of weapon
• Length and diameter of blade
• Estimation of how deeply object penetrated body
• Direction of penetration

 

Gunshot wounds

• Type of gun (eg: pistol, shotgun)
• Calibre of bullet
• Distance fired from

 

 

Clinical findings

Look

• examine patient carefully for all wounds
  • don’t forget to look in the axilla, groin, perineum, between buttocks
  • in the case of projectiles: look for possible exit wounds

Palpate

• examine abdomen for abdominal pain and peritonism
• If the wound might have a trajectory across the rectum, a careful PR should be performed

 

Investigations

Bloods

Standard trauma blood tests looking in particular for a decrease in haemoglobin

 

Plain radiographs

• An erect CXR may show intraperitoneal free air – however, this could be external air entrained into the peritoneal cavity by the penetrating object. It is most useful for determining potential thoracic injury.
• If the injury is caused by a GSW or projectile – use a paperclip taped over the skin that is open for posterior wounds and closed for anterior wounds and request an AXR and CXR

eFAST

• USS not validated for penetrating trauma
• If free fluid is seen on FAST, this would be an indication for further evaluation
• A negative FAST does not rule out intraabdominal injury in penetrating trauma
• For patients with upper abdominal stab wounds or any projectile wound: if unstable – eFAST can be utilised to rapidly assess for cardiac tamponade or tension pneumothorax/massive haemothorax.

CT abdomen/pelvis with contrast

Most patients with penetrating anterior abdominal wounds thought to breach the fascia will proceed to CT scan provided they are haemodynamically stable with no indications for immediate laparotomy.

Stable patients with penetrating injuries to the back, flank or buttock should have a CT scan, ideally with rectal contrast.

 

 

Management

Indications for immediate laparotomy

• peritonism/diffuse abdominal tenderness
• hypotension/shock
• evisceration
• penetrating object still in situ

 

Superficial wounds

Patients with superficial stab wounds with a wound base clearly visualised not penetrating the anterior rectus fascia can have their wounds repaired in ED and discharged if appropriate

 

Anterior wounds breaching fascia (patient stable)

Guided by CT results*

 

Posterior/flank wounds (patient stable)

Guided by CT results*

Disposition – interhospital transfer guidelines

 

penetrating abdo destination

 

References

 

1. Bhagvan S, Ng A, Civil I. Penetrating thoraco‐abdominal injuries: the Auckland City Hospital experience. ANZ journal of surgery. 2011 Sep 1;81(9):595-600.