Open Heart Massage

Anatomy and Physiology

Anatomy

Knowledge of cardiothoracic anatomy is critical during an open thoracotomy to access the heart for OCM. The procedure typically begins with a left anterolateral thoracotomy at the fourth or fifth intercostal space or, in certain cases, a median sternotomy. The surgeon must manage the lungs bilaterally, keeping them retracted to maintain a clear surgical field. The sternum is either sawed or clipped to access the heart, allowing exposure to the heart within the pericardium. The surgeon then incises through the pericardium to allow full access to the heart to initiate OCM and, in cases of cardiac tamponade, relieve pressure effectively.[9][10]

Careful dissection is necessary throughout the procedure to avoid damage to the phrenic and intercostal nerves and prevent vascular injury to the intercostal arteries, pulmonary vessels, and internal mammary vessels, crucial to the thoracic blood supply.[2][9] Once inside the pericardium, attention focuses on compressing the left ventricle while preserving the coronary arteries to maintain myocardial oxygenation. Additionally, the surgeon must be comfortable identifying the aorta above the diaphragm for cross-clamping and then separating it from the esophagus with their fingers so as not to clamp it.[10] Cross-clamping directs blood flow to the brain and heart, optimizing perfusion to essential organs. Mastery of this anatomy allows the surgeon to perform effective compressions, minimize iatrogenic injuries, and manage complications, ultimately improving patient outcomes in this critical intervention.

Physiology 

Perfusion to vital organs during cardiac massage may be monitored through end-tidal carbon dioxide (EtCO₂) levels. Since EtCO₂ is a byproduct of cellular respiration, its presence indicates that cellular metabolism is ongoing, suggesting adequate oxygen delivery. Oxygen delivery is determined by cardiac output and the oxygen-carrying capacity of the blood, which depends on the patient’s oxygen saturation and hemoglobin levels. Although the ROSC is not achieved until after internal cardioversion, manual compressions generate sufficient cardiac output to sustain oxygen delivery and support cellular metabolism.[10]

Results from multiple studies have demonstrated that OCM offers physiological advantages over other resuscitation methods, particularly in cases of traumatic cardiac arrest and in the operating room setting. OCM allows direct manual heart compression, which is associated with superior coronary and cerebral perfusion and yields higher perfusion pressures. This method enables the delivery of targeted, controlled compressions that effectively maintain systemic circulation to vital organs, including the brain and heart. In contrast, closed-chest compressions often fall short of producing the required perfusion pressures, especially in patients with thoracic injuries or after thoracotomy. These studies include: 

• A 1962 experimental study by Weale et al:
  • This study examined the effectiveness of 2 resuscitation methods that were compared using a sample of 19 dogs. Cardiac arrest was induced through ventricular fibrillation under general anesthesia, and the animals’ venous and arterial pressures were monitored via cannulation of the femoral vessels, with electrocardiograms (ECGs) recorded from chest wall electrodes. Inducing ventricular fibrillation with electric current, researchers observed an increase in venous pressure and a drop in arterial pressure. Later in the study, blood pressure was compared in 2 animals during closed-chest cardiac massage (CCCM) and OCM. Systolic blood pressure increased from 40 to 90 mm Hg in 1 animal and from 80 to 120 mm Hg in another when transitioning from closed to OCM. Diastolic blood pressure rose 30 mm Hg in the first animal and 15 mm Hg in the second.
  • Additionally, a decrease in mean venous pressure, ranging from 4 to 15 mm Hg, was noted after switching to OCM. The study concluded that CCCM was less effective because it produced lower mean arterial pressure (MAP) and higher venous pressure, causing poorer organ perfusion. The authors suggested that CCCM should be used temporarily until OCM can be performed.[11]
• A 1984 comparative study by Robert Bartlet:
  • In this, he examined 3 types of cardiac massage: CCCM, OCM, and direct mechanical ventricular assistance (DMVA), which involved a bell-shaped device that adhered to the heart’s apex and alternated between contracting and stretching the ventricles. The study was conducted on 15 anesthetized dogs, monitoring aortic pressure, pulmonary artery pressure, cardiac output, and ECG. After inducing cardiac arrest, CCCM was administered for 10 minutes. Following this, manual OCM was initiated in group I, while DMVA was used in group II at frequencies of 60 and 90 compressions per minute. Group III continued with CCCM.
  • During CCCM, a cardiac index (CI) of approximately 780 mL/min/m² was recorded, representing 19% of the control value, with a MAP of 26 mm Hg, or 23% of the control value. In group I, OCM at 60 compressions per minute produced a CI of 2078 mL/min/m² (52% of the control) and a MAP of 50 mm Hg (36% of the control). In group II, DMVA at the same frequency generated a CI of 2780 mL/min/m² (70% of the control) and a MAP of 72 mm Hg (65% of the control). When the compression rate was increased to 90 per minute, MAP and CI increased by 26% and 23% in the DMVA group and by 15% and 14% in the OCM group, respectively.[12]
• A 1984 comparative study conducted by Artur Sanders and colleagues:
  • This study compared coronary perfusion pressure during CCCM and OCM in 10 dogs. After inducing anesthesia, the dogs’ aortas were cannulated through their carotid arteries and their right atriums via their internal jugular veins, continuously measuring blood pressure at both locations. During CCCM, none of the dogs reached a coronary perfusion pressure above 30 mm Hg, a threshold linked to poorer outcomes.
  • Five dogs then underwent thoracotomy and transitioned to OCM, while the remaining 5 continued with CCCM. The group receiving OCM demonstrated significantly higher coronary perfusion pressure values than those on CCCM. Additionally, 4 of the 5 dogs in the OCM group achieved a ROSC, whereas none of the animals in the CCCM group experienced ROSC.[13]
• A recent review paper by Kornhall and colleagues:
  • This paper reviewed the available evidence on OCM and CCCM and proposed prior evidence that may support improved physiology and outcomes from OCM.[2] Physiologically, healthcare professionals know that the higher the coronary perfusion pressure, the more likely the cardiac arrest patient may achieve a ROSC. An animal study in mongrel dogs performed in 2003 demonstrated a coronary perfusion pressure of 38.2 mm Hg in OCM compared to only 20.3 mm Hg with CCCM.[14] Many animal studies consistently demonstrate this.[15][13] Furthermore, cerebral perfusion also concordantly improves with OCM and approaches near-normal values, whereas closed chest compressions lead to only 30% of normal cerebral blood flow.[16]
• A study performed by Boczar and colleagues in 1995:
  • This study was one of the primary human studies and showed that coronary perfusion pressure increased from an average of 7.3 mm Hg to 32.6 mm Hg when converting from CCCM to OCM.[17] Furthermore, mean CI values are more than double those of direct open compressions.[18]
• Other studies:
  • Few human trials have been published studying the outcomes of OCM. Most recently, in 2011, a study of 76 patients who experienced cardiac arrest after coronary artery bypass grafting surgery demonstrated a survival rate of 82% after immediate resternotomy with an OCM.[19] Results from another study in nontraumatic, out-of-hospital cardiac arrest showed ROSC in 58% of patients in the OCM group versus only 30% in the CCCM group.[20]

Despite these reassuring findings, these data must be interpreted with caution as the intervention of chest compression may be performed too late and may include a unique population of patients who underwent recent cardiac surgery.

Indications

An open approach is essential in managing cardiac arrest resulting from traumatic or nontraumatic hemorrhage. In these cases, external chest compressions or traditional cardiopulmonary resuscitation (CPR) may worsen outcomes by increasing stroke volume, accelerating blood loss, and causing further mechanical damage. Standard CPR is generally unsuitable for cardiac arrests caused by exsanguination or severe vascular injuries in the thoracic or abdominal regions, as it can expedite fatal blood loss. Survival in these scenarios relies on rapid transport to a hospital within minutes for ERT, often paired with damage control anesthesia and surgery. Notably, both external and internal CPR are only effective after bleeding has been controlled, and there is adequate mean intrathoracic pressure to make resuscitation meaningful. 

The American Heart Association, the Eastern Association for the Surgery of Trauma, and the International Liaison Committee on Resuscitation recommend OCM under certain circumstances, such as penetrating cardiac arrest.[21] ERT and thoracic aortic cross-clamping can be lifesaving in cases of exsanguination and cardiac arrest resulting from intrathoracic bleeding or life-threatening heart and hilar injuries as they aid in getting patients to the operating room for definitive repair and source control of the hemorrhage.[10] In cases of penetrating chest injuries with signs of life at the scene and witnessed cardiac arrest, ERT with OCM is indicated as it is successful up to 30 minutes after cardiac arrest, with survival rates of 10% to 15% and as high as 20% for stab wounds.[22] Authors report other indications for cardiac arrest after recent cardiac surgery and decompression of pericardial tamponade.[2][23][24] Some recommend OCM when standard advanced life support protocols do not restore spontaneous circulation within 5 to 10 minutes.[25] Other potential indications include abnormal chest wall anatomy preventing effective, closed-chest compressions, refractory ventricular fibrillation, and massive air embolism. 

For severe extrathoracic injuries, such as those involving the femoral vessels or severe trauma to the neck, death can occur within 5 to 10 minutes. Emergency thoracotomy or sternotomy provides direct access for source control, OCM, and rapid restoration of venous return through a central venous line or direct cannulation of the superior vena cava or right atrium. ERT is appropriate in cases of cardiac arrest resulting from blunt trauma if the patient arrives within 10 minutes of the witnessed arrest and is intubated or within 5 minutes if not intubated. Beyond these timeframes, the procedure is often futile, with survival rates of only around 0.2% for blunt trauma cases.[22]

Contraindications

ERT and OCM are high-stakes, last-resort procedures typically indicated for traumatic cardiac arrest or severe hemorrhagic shock with a reasonable potential for survival. However, significant contraindications to these procedures must be carefully considered. The only organic contraindication to OCM is the presence of a pulse.[9] Other key contraindications include known patient wishes precluding resuscitation, such as a "do not resuscitate" order, and a patient without previously witnessed signs of life upon hospital arrival. Blunt trauma patients who present with no cardiac activity and without pupillary response have an extremely low chance of meaningful survival and are generally contraindicated for ERT and OCM due to poor outcomes and resource considerations.

Additional contraindications include patients with prolonged prehospital downtime without any signs of life en route, as the likelihood of neurological recovery is minimal. The success of ERT in trauma patients has been closely linked to the time between cardiac arrest and the initiation of the procedure.[26] Severe, irreversible injuries—such as those involving significant damage to the brain, heart, or major vessels—or other unsurvivable trauma also contraindicate these interventions. ERT and OCM are generally not recommended for patients with severe underlying comorbidities that would limit their ability to survive even if they achieve ROSC. In cases of exsanguination, such as massive thoracic or abdominal bleeding, these procedures may not be viable if resources and surgical capabilities for definitive repair are unavailable.

Equipment

An ERT requires specific equipment to ensure rapid access to the thoracic cavity and immediate intervention in traumatic cardiac arrest situations. The following are typically needed for a well-prepared ERT setup:

• Sterile surgical instruments
  • Rib spreader (Finochietto or Tuffier retractors)
  • Scalpel and blades
  • Heavy scissors (Mayo or trauma scissors)
  • Large needle driver and sutures (eg, 3-0 or 4-0 polypropylene for cardiac repair)
  • Hemostats and large clamps for vascular control (such as Satinsky or DeBakey vascular clamps)
• Thoracotomy instruments
  • Rib shears, heavy scissors, or Gigli saw (if rib cutting is necessary)
  • Suction device with adequate tubing
• Hemostatic control tools
  • Vascular tourniquets
  • Large gauze sponges or laparotomy pads
  • Occlusive dressings
• Aortic cross-clamping instruments
  • Cross-clamp or aortic occlusion clamp for descending aorta isolation (commonly a Fogarty or Satinsky clamp)
  • Chest drain kit with tubing for pleural evacuation if necessary
• OCM supplies
  • Cardiac internal defibrillator paddles (if internal defibrillation is required)
  • Epinephrine and other resuscitative drugs for intracardiac or intravenous (IV) administration
• Monitoring and airway equipment
  • Endotracheal intubation kit (eg, laryngoscope, endotracheal tube)
  • Suction catheter and suction unit for clearing airways or blood
• Personal protective equipment 
  • Gown, gloves, mask, and eye protection for all personnel to minimize exposure to bloodborne pathogens during open thoracotomy

Personnel

Performing OCM in an operating room is a complex and time-sensitive procedure requiring a well-coordinated team of skilled personnel. Each member is critical in optimizing patient outcomes and ensuring rapid response. The core personnel for OCM typically include:

• Trauma or cardiothoracic surgeon
• Anesthesiologist 
• Surgical assistant 
• Scrub nurse or surgical technologist
• Circulating nurse

When OCM is performed in the emergency room (ER), the team composition is tailored for rapid, life-saving intervention, often with fewer specialized resources than in the operating room. Key personnel typically include:

• Trauma surgeon or ER physician
• ER or trauma nurse
• Anesthesiologist (if available)
• Respiratory therapist (if available)
• Circulating nurse or ER technician
• Support staff for blood bank and laboratory communication

Preparation

In emergencies requiring OCM, obtaining informed consent is typically impractical, and healthcare professionals are generally exempt from this requirement due to the immediate, life-saving nature of the procedure. Nonetheless, clinicians must check for and document the patient’s known code status as soon as feasible. This step ensures alignment with any preexisting patient directives, such as not resuscitate orders, and upholds ethical and legal standards in patient care.

Preparation for OCM is a rapid, highly coordinated process due to the life-threatening conditions often necessitating the procedure. Essential preparation steps include:

• Team communication
  • Prior to OCM, each team member should have clearly defined roles, especially in emergencies. The trauma surgeon or lead physician usually coordinates, while the rest of the team (including nurses, anesthesia providers, respiratory therapists, and technicians) are assigned specific tasks, such as airway management, monitoring, and blood product administration.
• Gathering equipment and supplies
  • Rapid access to a thoracotomy tray with sterilized instruments is crucial. Additionally, supplies like suture material, hemostatic agents, and medications, including vasopressors and sedatives, should be readily available. Preparation also includes immediate access to blood products, fluids, and resuscitative drugs.
• Patient positioning and preparation
  • The patient is positioned supine on the ER bed with the arm abducted to allow the trauma team access to the thoracic cavity. Due to the urgency, a complete aseptic technique is often omitted, or a rapid application of skin preparation (chlorhexidine gluconate or povidone-iodine) may suffice.
• Airway management
  • The patient’s airway is secured (typically by intubation) to maintain adequate oxygenation during OCM. An anesthesia clinician or other skilled clinician manages ventilation, usually with 100% oxygen, to optimize tissue perfusion.
• Monitoring and intravenous access 
  • Continuous vital sign monitoring is set up for real-time feedback on patient status. Ideally, multiple large-bore intravenous lines are established to facilitate rapid infusion of fluids, blood products, or medications. If time permits, arterial lines or central venous access can provide more precise hemodynamic monitoring.
• Coordination with ancillary services
  • Immediate communication with the blood bank ensures prompt availability of blood products for transfusion, as many patients with OCM have extensive blood loss. Lab support is also on standby to expedite critical labs, such as blood gases and coagulation studies.
• Readiness for possible escalation to surgery
  • If the patient’s condition stabilizes, they can be transferred to the operating room for definitive care. The operating room team may be placed on alert for a potential handover to continue the resuscitation in a more controlled environment.

Technique or Treatment

Access to the heart is typically achieved through a left anterolateral thoracotomy, which can be completed in under a minute, provided a trained team is present.[27] A cardiothoracic surgeon with experience in performing a rapid median sternotomy in under 2 minutes is preferable. However, a nonspecialist surgeon may also be able to perform an emergency, open thoracotomy in 2 to 3 minutes.[9] The following approaches are used to access the heart in cases where OCM is needed: 

Left Anterolateral Thoracotomy

The patient is positioned supine or slightly left lateral decubitus, with the left arm raised if time allows. A 10 to 15 cm incision is made along the left fourth or fifth intercostal space, extending from the sternal border to the midaxillary line. The ribs are carefully separated using rib retractors, with the division of the intercostal muscles and ligating the internal mammary artery if more comprehensive access is required. The left lung is gently retracted to expose the pericardium, ensuring lung protection for a clear surgical field. The pericardium is then identified and incised longitudinally, anterior to the phrenic nerve, taking care to avoid nerve injury. The pericardial edges are pulled aside using sutures or clamps. OCM is performed once the heart is exposed by compressing the heart rhythmically with the surgeon's preferred technique. The descending thoracic aorta is located and cross-clamped if necessary to prevent further bleeding and enhance coronary perfusion.

Bilateral Anterior Thoracotomy Approach (Clamshell)

The patient is supine with both arms extended and immobilized to allow adequate access to the thoracic cavity. Using a scalpel, the surgeon makes a bilateral transverse incision along the fourth or fifth intercostal space, extending across the midline from the left midaxillary line to the right midaxillary line. This incision divides the sternum horizontally, usually using heavy scissors or a Gigli saw, facilitating a comprehensive view of both hemithoraces. After the incision, rib retractors are used to separate the ribs widely, providing broad exposure to the thoracic cavity. Both lungs are gently retracted to minimize damage and enhance visibility for the subsequent steps. A midline incision is made in the pericardium to access the heart, avoiding injury to the phrenic nerves. Retracting the pericardium improves visualization and facilitates manipulation of the heart. OCM is performed using the surgeon's preferred technique. 

Median Sternotomy

The patient is supine with arms extended, ensuring the head is stabilized to prevent neck strain. A midline vertical incision is made from the sternal notch to the xiphoid process directly over the sternum. Sternal access is achieved using an oscillating saw or sternal shears to divide the sternum longitudinally, requiring precision to avoid damaging underlying vascular or cardiac structures. A sternal retractor is placed to separate the 2 halves of the sternum, allowing for full visualization of the mediastinum. Bilateral lung and tissue retraction is performed to keep the field clear for safe cardiac access. The pericardium is then incised longitudinally along the midline, lifting the tissue to prevent contact with the heart. The pericardial edges are retracted or sutured to improve exposure. OCM is performed. If necessary, the ascending or descending aorta is located and cross-clamped, depending on the clinical situation, to enhance visibility and manage blood flow.

OCM requires precise techniques to restore circulation while minimizing cardiac trauma effectively. The 2 main approaches—the 2-handed and single-hand techniques—are described below: 

OCM Techniques

Wise and colleagues recommend a 2-handed technique for OCM, where 1 flat hand is placed beneath the heart's posterior surface and the other on the anterior surface.[9] The heart is then gently compressed from the apex upward at approximately 100 beats per minute (aligning with Advanced Cardiac Life Support guidelines), ensuring not to use fingertips, as they increase the risk of myocardial injury. Alternatively, a single-hand technique can be employed if the clinician's hand is large enough. In this approach, the clinician’s straight fingers are positioned on the heart’s posterior surface near the apex, with the thumb on the anterior surface. Maintaining the heart horizontally is essential during OCM; lifting the apex could hinder venous filling. Additionally, an assistant may compress the descending aorta to maximize blood flow to the coronary arteries and cerebral vasculature.[9] If spontaneous circulation is restored, the incision is covered with sterile, saline-dampened gauze, and antibiotics targeting skin flora are administered. Definitive thoracotomy closure, ideally by a cardiothoracic surgeon, is recommended as soon as possible.

Complications

OCM is an invasive, high-risk procedure often performed as part of ERT, which carries substantial risks of complications commonly associated with open thoracic surgeries. Injuries to the intercostal vessels, nerves, lungs, pericardium, and heart muscle may occur during tissue dissection. Additionally, the procedure risks damage to major vascular structures, including the internal thoracic vein, pulmonary veins, and coronary vessels, which can lead to significant hemorrhage. Pneumothorax is also a concern, especially if lung tissue is inadvertently damaged during the procedure, leading to air escaping into the pleural space. Complications following OCCM include a range of potential issues, with postoperative wound infection rates estimated between 0% to 9.1% and mechanical cardiac injury occurring in 0% to 1.4% of cases.[1] In a 2011 review of 123 OCM cases, 51% of the procedures were deemed unlikely to benefit the patients due to poor survival prognosis, ultimately resulting in all 63 patients’ deaths in the intensive care unit despite the temporary ROSC in 4 patients. This study highlighted the need for careful patient selection to avoid unnecessary interventions, as demonstrated by using 335 units of concentrated red blood cells and 3 instances of occupational blood exposure.[28]

Due to the invasive nature of OCM, nearby structures such as the phrenic and intercostal nerves and the intercostal, pulmonary, and internal mammary vessels are susceptible to damage.[2][9] Mechanical injuries to the heart, including to the pericardium, myocardium, or coronary vessels, can arise from direct manipulation, increasing the risks of complications. In cases requiring thrombolysis for complications like massive pulmonary embolism or stroke, OCM may further complicate management since the thoracotomy site is a relative contraindication for systemic thrombolysis; in such cases, alternative therapies like embolectomy or localized thrombolysis should be considered.[2] Even if the patient survives, infection risk remains high, as many emergency thoracotomies are performed without a complete aseptic technique, making wound management and postoperative care essential to minimizing the risk of mediastinitis or other infections.

Finally, there is a risk of neurological deficits following OCM, particularly in cases where blood flow to the brain is compromised during cardiac arrest. This can lead to poor neurological outcomes even if spontaneous circulation is restored. Results from a study by Patel et al concluded that to improve the rate of neurologically intact survivors, novel resuscitative techniques targeting cerebral perfusion must be investigated, as existing techniques are inadequate.[8] While OCM can be life-saving, it carries a spectrum of complications that must be carefully managed to optimize patient outcomes.

Clinical Significance

OCM is a critical emergency technique, particularly for severe trauma cases and cardiac arrests where closed chest compressions may not be adequate. Traditionally, before closed-chest compressions became standard, surgeons routinely relied on OCM to maintain circulation during cardiac arrest. Some study results indicate that OCM may be more efficient in sustaining circulation than closed compressions. For example, results from a 1953 study found a recovery rate of 28% among patients who received OCM, and results from a subsequent 30-year study showed that performing open cardiopulmonary resuscitation within 4 minutes of arrest resulted in recovery rates up to 58%, with patients often neurologically intact.[29][30] However, recent comparative data are limited; results from a 2016 observational study on traumatic cardiac arrest found no significant improvement in EtCO₂ or ROSC in patients receiving OCM following failed closed compressions relative to those who only received closed compressions.[3]

One novel approach described in recent literature involves a transdiaphragmatic method to perform OCM during laparotomy.[31] In a case series of 6 patients experiencing cardiac arrest during surgery (4 liver transplants and 2 trauma cases), the heart was accessed through a diaphragmatic incision, resulting in the ROSC in 3 patients, 2 of whom survived intensive care unit transfer and 1 to discharge. While OCM remains limited by its invasive nature and associated risks, including potential injury to thoracic structures and infection risk, it can be a lifesaving measure when used judiciously in cases where rapid surgical intervention is available. These studies highlight the potential of OCM to improve outcomes in highly controlled, specific circumstances, especially when applied early and with skilled surgical support.

Enhancing Healthcare Team Outcomes

Effective open cardiac massage (OCM) implementation in emergency settings requires advanced technical skills, strategic planning, and interprofessional communication. To ensure optimal outcomes, clinicians need a thorough understanding of thoracic anatomy, surgical techniques, and resuscitative protocols. Precise execution of OCM relies on the clinician’s ability to perform complex maneuvers under high-pressure circumstances, particularly understanding when to intervene and how to maximize circulation while protecting vital structures. The clinical strategy includes prompt decision-making about OCM indication, timing, and coordination with the surgical team to ensure the procedure is performed safely and effectively. Each team member’s role, from initiating the incision to compressing the heart, must be clear, with rapid, concise communication to reduce risks and enhance the likelihood of return of spontaneous circulation with minimal complications.

Interprofessional communication and care coordination are essential to patient-centered care and safety in OCM cases. Healthcare professionals must maintain open lines of communication, ensuring that everyone involved in the procedure is aware of the patient’s code status, surgical preparation, and emergent needs. Nurses play a vital role in assisting with patient positioning, managing equipment, and ensuring sterility, while pharmacists can provide critical medication management, including anticoagulation reversal or administration of emergency medications. This synchronized, team-oriented approach helps mitigate risks, improve patient outcomes, and streamline the process of postresuscitation care. Such coordinated effort supports optimal patient safety and strengthens team performance, fostering a collaborative environment where each member contributes to effective, life-saving care.