Introduction

The aim of this post is to give an account of the steps involved in performing a resuscitative clamshell thoracotomy for chest trauma. I will highlight some of the relevant technical as well as a few non-technical pitfalls. Please refer to my  previous post on the indications for a clamshell incision.

It is exceptional for any one civilian general surgeon, working outwith a large trauma centre, to perform more than a handful of resuscitative trauma thoracotomies in the course of her/his career. As a result, this limited personal experience needs to be supplemented by simulation training on anaesthetised animals and/or human cadavers.

The less experienced surgeon has a significant psychological barrier to overcome before deciding to perform a resuscitative thoracotomy. The surgeon’s unease to act and the inevitable delay in the decision making that follows, could be further reinforced by the cognitive biases  such as the “diagnostic momentum” bias. In diagnostic momentum, the surgeon continues a clinical course of action already instigated by the team without considering changing the plan, particularly when the original plan is commenced by a senior clinician. Diagnostic momentum is a potential bias for the unwary junior member of any multidisciplinary team.

It is worth remembering that the clamshell incision is only a means to an end, and the main focus should be on the surgical manoeuvres potentially needed for damage control following gaining access. Resuscitative thoracotomy should ideally be done in a well-equipped environment and only by those who have the necessary experience in dealing with the range of injuries commonly encountered.

I hope it is clear from the above description that the challenges of performing a resuscitative thoracotomy include the ability to decide when to operate, possessing the technical skills for performing a thoracotomy incision, and the surgical experience to know what to do once in the chest.

Clamshell incision

1. If the patient is stable enough, transfer the patient to the operating theatre. This will delay the procedure but with a trade-off of a far superior surgical environment. If the patient is unstable, proceed to performing an emergency room thoracotomy.
2. Use an antiseptic solution to rapidly sterilise the anterior and lateral thoracic wall.
3. Wear sterile gloves, eye protection and a gown.
4. It is essential to remain calm; give clear instructions.
5. Think one step ahead at all times and verbalise your thoughts for the team.
6. Don’t injure yourself or others!
7. Work in a well-lit area.
8. Privacy from the gaze of the other patients/relatives is essential.
9. The anaesthetist should ET tube the patient with both arms positioned above the patient’s head. The latter will help to maximise the intercostal spaces.
10. Stand to the patient’s left side.
11. having an assistance is a luxury.
12. Use any large (No. 21) blade.
13. Diathermy has no use.
14. Feel for the xiphoid process and locate the inframammary folds (in females you may have to lift the breasts up).
15. Make an incision along the left 4th or 5th intercostal space over the inferior breast crease, starting an inch lateral to the edge of the sternum and finishing at the mid axillary line. The incision should be well above the costal angle and above the xiphisternum.
16. Make confident, deep, and long strokes with the scalpel. Avoid making light, multiple strokes; it slows you down and makes the wound bleed more.
17. Ignore any bleeding points from the skin, fat, serratus anterior and intercostal muscles.
18. Use heavy Mayo-type scissors to complete the division of the intercostal muscles and pleura.
19. Use a Finochietto rib spreader to open the intercostal gap. The spreader should be placed at the most inferolateral aspect of the incision so that it does not obscure access. This completes the left anterolateral thoracotomy.
20. If required, extend this left sided incision over onto the right side by make a symmetrical incision on the right chest (clamshell).
21. Sternotomy is best done after completion of both left and right anterolateral thoracotomies. Divide the sternum using a Lebsche knife and a mallet. You can use a Gigli saw, a bone cutter, plaster cast scissors or even your hands to crack open the sternum if you have to. You need to be making rapid progress.
22. The internal mammary vessels may not bleed due to hypotension. However, these will bleed postoperatively if not secured. Identify them carefully and tie them securely during the thoracotomy closure.
23. Lift the sternum and run your fingers gently along the fibrous plane between the posterior surface of sternum and the heart. The sternum is lifted up, like opening the front car bonnet.
24. A second Finochietto may be applied to the right thoracotomy if available. This completes the clamshell thoracotomy.

Introduction

In this post I will attempt to give an account of the indications for an emergency thoracotomy in chest trauma. The discussion will focus on penetrative chest injuries causing haemodynamic instability, and when CT scan preoperatively cannot be obtained safely. I will then discuss factors that may influence the surgeon’s decision for the choice of incision. The step by step technique for each approach will be covered separately. Dealing with major chest trauma is often stressful for doctors. Knowing when and how to perform an emergency thoracotomy quickly but safely can be life-saving.

Indications for Surgery

Most patients in need of emergency thoracotomy are often too unstable to go through a CT scan. What makes a patient cardiovascularly too unstable to undergo a CT scan depends on a combination of two factors: 1) the patient’s blood pressure and 2) the ease of access to the scanner. It is important to highlight that not all accident and emergency departments have rapid access to an on-site CT scanner. Instead, it is the bedside clinical judgement that is the decider. It is also fair to say that emergency thoracotomy has almost no role in the management of blunt decelerating injuries, since most of these patients unfortunately either die on route or die shortly after arrival at the hospital.

The vast majority of patients in need of emergency thoracotomy are those with penetrating trauma. In the UK penetrating chest trauma is most commonly caused by stab injuries and less commonly by gun shots. When compared to a gun shot injury, a knife injury often involves fewer injured organs, and unlike a gun shot, a knife injury does not involve both an entry wound and an exit wound.

The most urgent of all penetrating chest injuries is a stabbed heart. This should be suspected in any penetrating injury to the anterior thoracic wall. The patient could be showing clinical signs of tamponade, including muffled heart sounds, raised JVP, low BP, and pulsus paradoxus (a drop of at least 10 mmHg in arterial blood pressure with inspiration). FAST scan could be very useful when available, but these patients often require urgent surgical exploration. 

Many patients would have had a chest drain(s) soon after their arrival at the emergency department and the volume of blood aspirated from any drain would have been recorded. A volume of 1.5 litres or more is often taken as an indication for a thoracotomy. However, this should be put in the context of the individual patient’s clinical picture. If such a patient is clinically stable without ongoing blood loss through the drain, an emergency thoracotomy may be deferred, pending the results of a CT scan.

Choice of Incisions

For most clinical scenarios, and when no pre-operative imaging is available, the default is a clamshell incision. The incision often starts as a left antero-lateral thoracotomy through the 4th intercostal space. At times this my be started from the right side if the problem clearly stems from the right chest. The surgeon should have a very low threshold for extending this incision to the contralateral intercostal space for a full clamshell. This provides excellent exposures of aorta, heart, lungs and oesophagus, however it provides less optimal views of the superior mediastinum particularly for injuries to the base of the neck and the superior thoracic aperture. If required, a sternotomy can be added to a clamshell. However in a known injury to the superior mediastinum, a midline sternotomy may be the best approach initially. A special mention is due for injuries over the right thoracoabdominal area. This area extends from the right 5th intercostal space superiorly and a horizontal line crossing the most inferior aspect of the rib cage inferiorly. In this case, and when no preoperative imaging can be obtained due to patient’s condition, a midline laparotomy is often the starting point to look for any liver trauma. Occasionally a pericardial window can be made from the cephalad end of the laparotomy incision, for a rapid inspection of the pericardial space to check for cardiac tamponade.  The laparotomy can then be extended into the left chest over the 7th intercostal space for a left thoracoabdominal incision for a more definitive approach to the heart. A laparotomy can always be abandoned and a clamshell incision made instead, in case of unexplained hypotension but a negative laparotomy. You notice that the trauma surgeon should continuously reassess the adequacy of any exposure and change tacks as required.