Overview

Definition:
-Clamshell thoracotomy, also known as an anterior clamshell incision or transverse sternotomy, is an emergency surgical approach that provides wide exposure of both hemithoraces, the mediastinum, and the heart
-it is typically employed in life-threatening thoracic trauma or cardiac emergencies requiring rapid access for resuscitation and definitive repair.
Epidemiology:
-While not a common procedure, clamshell thoracotomy is primarily indicated in severe, high-energy thoracic trauma cases, particularly those with exsanguinating hemorrhage or suspected massive intrathoracic injury
-its incidence is directly related to the prevalence of severe trauma requiring emergent thoracotomy, with estimated rates of 0.1% to 1% of all emergency department thoracotomies.
Clinical Significance:
-This technique is critical for rapid control of life-threatening bleeding from great vessels, cardiac rupture, or massive hemothorax
-it allows for immediate cardiac resuscitation, tamponade release, and access to both lungs and the entire thoracic cavity, making it a vital skill for trauma surgeons and cardiothoracic surgeons managing critically ill patients.

Indications

Emergency Indications:
-Massive hemothorax with hemodynamic instability
-cardiac tamponade requiring emergent decompression
-exsanguinating hemorrhage from thoracic great vessels (aorta, pulmonary artery, vena cavae)
-suspected cardiac rupture or great vessel injury in a hemodynamically unstable patient
-blunt chest trauma with flail chest and severe respiratory compromise unresponsive to ventilation.
Relative Indications:
-Complex bilateral pulmonary contusions with refractory hypoxemia
-severe esophageal or tracheal injury requiring immediate repair
-suspected aortic transection in a hemodynamically compromised patient.
Contraindications:
-Non-survivable injuries (e.g., extensive brain injury, avulsed organs)
-patient refusal
-severe coagulopathy precluding surgical intervention
-lack of appropriate surgical expertise or resources.

Preoperative Preparation

Patient Assessment:
-Rapid assessment of ABCs (Airway, Breathing, Circulation)
-immediate hemodynamic monitoring (arterial line, central venous access)
-initiation of massive transfusion protocol if indicated
-rapid intubation and mechanical ventilation
-portable chest X-ray if time permits, but not to delay intervention.
Surgical Team Readiness:
-Ensure availability of a surgical team experienced in thoracic surgery and trauma
-confirm availability of all necessary surgical instruments, including sternal saw, rib retractors, and hemostatic agents
-prepare for massive blood product transfusion.
Anesthesia Considerations:
-General anesthesia with controlled ventilation
-initiation of neuromuscular blockade
-careful fluid management and hemodynamic support
-readiness for rapid induction and maintenance of anesthesia under stressful conditions.

Procedure Steps

Incision Placement:
-A transverse incision is made across the sternum, typically from the anterior axillary line on one side to the anterior axillary line on the opposite side, curving superiorly around the breasts
-it can be extended superiorly around the clavicles if needed for superior mediastinal access.
Sternal Division:
-The sternum is divided longitudinally using a sternal saw, from the suprasternal notch to the xiphoid process
-care is taken to avoid injury to underlying mediastinal structures, particularly the heart and great vessels.
Retraction And Exposure:
-A large rib spreader or sternal retractor is used to spread the sternal halves apart, creating a wide opening to expose both pleural cavities and the mediastinum
-this "clamshell" opening allows for unparalleled access.
Surgical Intervention:
-Immediate identification and control of bleeding sources
-management of cardiac tamponade by evacuation of pericardial effusion
-repair of cardiac or great vessel injuries using sutures, vascular grafts, or other hemostatic techniques
-lung repair or resection as needed
-control of massive hemothorax by direct ligation or cautery.
Closure:
-After hemostasis is achieved and injuries are repaired, the sternum is approximated and secured with sternal wires
-ribs are approximated, and chest tubes are inserted into each hemithorax for drainage
-the overlying soft tissues are closed in layers.

Postoperative Care

Monitoring:
-Intensive care unit (ICU) admission is mandatory
-continuous hemodynamic monitoring, including arterial and central venous pressures
-mechanical ventilation with gradual weaning
-close monitoring of chest tube output and respiratory status.
Pain Management:
-Aggressive pain control is crucial, often requiring patient-controlled analgesia (PCA) with opioids or epidural analgesia
-adequate pain relief facilitates deep breathing and mobilization.
Chest Tube Management:
-Serial chest X-rays to ensure proper lung expansion and drainage
-management of chest tubes to prevent kinking or dislodgement
-monitor for signs of pneumothorax or hemothorax recurrence.
Rehabilitation:
-Early mobilization as tolerated
-pulmonary physiotherapy and breathing exercises to prevent atelectasis and pneumonia
-gradual return to normal activity levels.

Complications

Early Complications:
-Hemorrhage from great vessels or heart injury
-cardiac arrhythmias
-mediastinal hematoma
-pneumothorax
-infection
-wound dehiscence
-respiratory failure
-acute kidney injury.
Late Complications:
-Chronic pain at the sternotomy site
-sternal non-union or malunion
-restrictive lung disease
-paradoxical chest wall movement
-adhesions and chronic pleural effusion
-incisional hernia.
Prevention Strategies:
-Meticulous surgical technique to avoid iatrogenic injury
-prompt recognition and management of bleeding
-adequate chest tube drainage
-aggressive pain control and pulmonary physiotherapy
-judicious use of antibiotics
-careful wound closure.

Key Points

Exam Focus:
-Clamshell thoracotomy is an emergent procedure for severe thoracic trauma or cardiac arrest with reversible cause
-it offers bilateral chest exposure for rapid resuscitation and repair
-indications include massive hemothorax, cardiac tamponade, and great vessel injury in unstable patients.
Clinical Pearls:
-This is a salvage procedure
-speed is paramount
-anticipate massive hemorrhage and have blood products ready
-careful sternal division and retraction are key to avoiding further injury
-chest tube management is critical post-operatively.
Common Mistakes:
-Delaying the procedure in a hemodynamically unstable patient
-inadequate exposure leading to incomplete control of bleeding
-iatrogenic injury to great vessels or heart during sternal division
-insufficient postoperative pain management hindering lung expansion.