Procedure

Emergency Department Thoracotomy

Indications

Best indicated to repair a (predicted) simple injury of the chest causing a serious physiological insult.

Decision is dictated :
- mechanism of injury
- physiologic status of pt
- timing of events

Distinguish Vital Signs vs Signs of Life

Vital Signs
Palpable pulse
Recordable BP
Spontaneous respiratory activity

Signs of Life
Pupillary response
Spontaneous ventilatory effort
Palpable pulse
Extremity movement
Cardiac electrical activity

Clear Indication for EDT
1. Penetrating thoracic injury with SOL in pt not responding to fluids
- and losing vital signs in ED or on arrival to ED

Possible Indications
1. Penetrating abdominal injury with at least one field SOC and <15min CPR
2. Blunt trauma who had field SOL and lose SOL within 5 mins of arrival into ED (controversial)

Contra-Indications
1. No field SOL in penetrating or blunt trauma.
2. Blunt trauma and >5min prehospital CPR
3. Penetrating trauma and >15 min CPR.

Theory

Injury Patterns
Targets a few basic injury patterns:
- release of pericardial tamponade
- control of intrathoracic vascular or cardiac haemorrhage
- correction of bronchovenous air embolism
- open-heart massage
- temporary occlusion of the descending thoracic aorta

Release of Pericardial Tamponade
Muffled heart sounds, hypotension, jugular venous distension (Beck's triad)
- not reliably present, need a high index of suspicion.
USS v. helpful.
Compromises diastolic filling, preload and thus stroke volume.
EDT only relevant to pt's presenting in the final stages of tamponade and with collapse; else could be done in OR.

Control of Intra-thoracic Vascular / Cardiac Haemorrhage
Temporary control pending definitive repair in OR.
Cardiac injuries with suture ligation, finger occlusion or skin staplers.
Chest wall injuries with vascular clamps or direct packing
Lung lacs with staples, sutures or temporary hilar clamping.

Temporary Occlusion of Descending Thoracic Aorta
Reduces blood loss below diaphragm and shunts to brain and heart
- risks cardiac failure due to ventricular dilation, reperfusion injury
--> use your thumb, remove if rhythm restored, minimizing complications
Simultaneously massage heart with non-dominant hand against underside of sternum.

Open Cardiac Massage
Closed chest compressions generate 25-40% of baseline cardiac output only.
- can reasonably perfuse heart and brain at least
- but far less benefit in shock because of critically low blood volume
Hence open cardiac massage remains only effective post-injury CPR option.

Bronchovenous Air
Systemic / left sided air embolism due to fistula between pulmonary bronchus and vein.
Usually penetrating but can be blunt when rib # or shear injury.
Causes haemodynamic collapse, cardiac arrest, exacerbated by +ve pressure ventilation
- can suddenly have cardiovascular collapse after intubation
Noticed on opening the chest:
- ant descending coronary artery has bubbles in it.

Special Preparation
Notify CardioTx and OR to prepare
Massive transfusion protocol

Prep
Supine with left arm raised
Splash prep
Stand on pt's left.
The left chest will be opened.

Incision
Start just to the right side of sternum
5th ICS to left mid-axillary line, following gentle curve of associated rib
Male: generally just below the nipple
Female: just below the inframammary fold

Procedure

1. Incise
2. Divide intercostal muscles with scissors or scalpel
3. Sharply incise pleura
4. Finocheietto retractor, handle directed laterally and toward feet

Extension across sternum?
Lebsche knife and mallet or rib shears
Clamshell by carrying similar incision over to R side.

Pericardotomy
Incise pericardium longitudinally from aortic root to apex
Avoid the phrenic nerve laterally!
Remove clot.
Temporarily repair cardiac lacerations using skin stapler or sutures.
- do so quickly and with a temporary mindset - will go to theatre for definitive repair.
Using a Foley is traumatic to cardiac wounds and should be avoided
Delay cardioversion until lacerations repaired.

Aortic cross-clamp
Thoracic aorta accessed by retracting lung medially
- slide hand along left lateral thoracic wall to feel thoracic vertebral body
- aorta on anterior lateral surface, and immediate occlusion with the thumb is easily achieved
May need to sometimes sharp dissect with scissors (or blunt with surgeon's hand) to isolate aortic segment to place a clamp.
- then need to dissect pleura off aorta else ineffective and can damage esophagus and intercostal arteries.

Open cardiac massage
Often while maintaining aortic control.
Both hands in the chest.
Open pericardium
Right hand lifted posterior heart; gently pushed against underside of sternum.
- both hands cupped and opposed at the wrist
- heart gently compressed from apex toward aortic root.
Internal cardiac defib often required; (*only 15-30J energy needed)

Evacuation of bronchovenous air embolus
Once recognized, isolate injured lung.
Take down inferior phrenic ligament, clamp hilum with a vascular clamp or soft bowel clamp.
Grasp ascending aorta with thumb and index finger, start cardiac massage (removes air from coronary vessels).
Aspirate air from left ventricle using an 18g needle.
Eipnephrine administered 1:10,000 down the ET tube, drives air bubbles out of cerebral circulation and vital organs.
Once cardiac activity achieved, lung injury oversewn or stapled; lobectomy in minority of cases.

Other useful adjuncts
If no cardiac activity, obtain ABG and start cardiac massage.
- if pH <7, achieve fibrillation; correct acidosis with bicarbonate.
--> once fine fibrillation, attempt progression to coarse fibrillation with epinephrine into ET tube or central line (avoid direct cardiac puncture as may bleed).
Once pH 7.2, defibrillate the coarse fibrillation.
Then deal with hypothermia, coagulopathy and ongoing acidosis.
Transport to operating room - proper lighting, instrumentation etc.

Clamping pulmonary hilum
If massive bleeding from central pulmonary vasculature.
Momentarily pause ventilations, retract L lung superiorly and medially
Curved clamp e.g. Satinsky around hilum.

Outcomes?
Basd on mechanism and pattern.
Overall survival for penetrating trauma averages 20%
- best if isolated cardiac injury
Blunt trauma has terrible survival 0-2%.

Post-Op

Complications

Alternatives and Controversies