Trauma : knife through chest

Ultrasound images and text Genevieve Carbonatto

A 53  year old lady presents to the Emergency Department after having stabbed herself in the chest in a suicide attempt. The knife is still in the chest close to and to the left of the sternum  in the 5th intercostal space. She is alert and orientated, she says she stabbed herself some time ago but cannot remember when. Her  saturations are 96% on room air, HR 110/min, BP 130/80, air entry is present  bilaterally, no crepitus. There is no active bleeding but there is a significant clot surrounding the knife entrance wound. Bloods are taken for a group and hold, FBC, UEC and coagulation profile.

An emergency point of care ultrasound is performed. There is bilateral lung sliding. This is his ECHO

There is some pericardial fluid, but no clotted blood.

She is taken to theatres within 18 minutes.

The knife in the chest in theatre just before being removed.

Discussion

Penetrating injury to the chest may involve the following organs (4)

• Chest wall
• Pleura and lung
• Heart
• Oesophagus
• Diaphragm
• Thoracic blood vessels
• Thoracic duct
• Mediastinal structures

Clinical presentations (1) of a patient with cardiac injury can be divided into 3 groups:

1.  Chest wound with little or no sign of shock, possible cardiac penetration
2.  Chest wound, hypotension often responding to transfusion, probable cardiac penetration, no haemodynamic difficulty
3. “Apparently dead” chest wound , unconscious, absent pulses, dilated pupils, no recordable BP

Hypotension from penetrating injury to the chest may be due to:

• cardiac tamponade
• bleeding into chest (haemothorax)
• bleeding externally
• injury to the great vessels
• tension pneumothorax

From the site of penetration the  likely areas of heart involved are :

• Between sternum and nipple on the left – probable  right ventricular injury
• Lateral to nipple on the left – possible left ventricular injury
• Medial to the nipple on the right – right atrium and great veins at risk
• Posterior to the midaxillary line on the right – left atrium at risk

The heart may also be penetrated if the injury is subxiphoid or subcostal

Applied Anatomy: The Construction Of The Human Body :  Gwilym G. Davis.. The shaded area indicates where penetrations are frequently associated with cardiac injury

The management (5) of chest injuries depends on the clinical condition of the patient on presentation to the Emergency Department and the type of injury ( gunshot vs stab)

1.  Patients in cardiac arrest or imminent cardiac arrest require an  immediate rescuscitative thoracotomy in the Emergency Department without any investigations. The overall survival rate depends on the mechanism of injury, the prehospital time and the indication for the thoracotomy. One study reported an overall survival of 8.3% for stab wounds and 4.4 % for gunshot wounds.
2.  Patients with severe hypotension  require an emergency ultrasound to look for pericardial fluid, haemothorax and pneumothorax and immediate transfer to theatre for a thoracotomy with little delay. A chest Xray may be helpful if this does not contribute to delay to theatre.
3. Patients who are mildly hypotensive with no evidence of cardiac injury on ultrasound may be given fluids to correct the hypotension and treated appropriately for possible causes of hypotension such as blood loss to the chest (chest drain) or externally
4.  Patients who are not hypotensive and have no evidence of pericardial fluid on ultrasound may undergo time consuming investigations looking for vascular injuries, diaphragmatic injuries or oesophageal injuries such as CT scan with contrast ,  bronchoscopy, angiography, oesophagoscopy, endoscopy, laparoscopy (to evaluate for diaphragmatic injuries)

Teaching point : In the past haemoperocardium, haemothorax and pneumothorax were injuries diagnosed by  clinical examination, chest Xray, ECG and pericardiocentesis. Now emergency ultrasound has replaced much of this and become a valuable and time saving tool to rule out haemopericardium, haemothorax and pneumothorax.

References

1. Ann R Coll Surg Engl. 1983 Sep; 65(5): 304–307.PMCID: PMC2494362 PMID: 6614765 Emergency surgery for stab wounds to the heart
2. This section is from the book “Applied Anatomy: The Construction Of The Human Body”, by Gwilym G. Davis.
3. Ann Surg 1979 Jun, 189(6): 777-783 Principles for the Management of Penetrating Cardiac Woundshttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC1397211/by J Evans – ‎1979
4. Medscape: Penetrating Chest Trauma Treatment & Management Updated: Dec 18, 2017  Author: Rohit Shahani, MD, MS, MCh; Chief Editor: Jeffrey C Milliken, MD
5. Scand J Surg. 2002;91(1):41-5.Penetrating injuries of the chest: indications for operation.Demetriades D1, Velmahos GC