Open Heart Massage

Anatomy and Physiology

When a surgeon performs an open thoracotomy to access the heart, knowledge of cardiothoracic anatomy is crucial. During dissection, the lungs must be held out of the way bilaterally. After sawing or clipping through the sternum and accessing the heart encased in the pericardium, the surgeon may incise through the pericardium to allow full access to the heart in the case of cardiac tamponade.[6] They must take care to avoid the phrenic and intercostal nerves[1][6] and vascular injury to the intercostal, pulmonary, and internal mammary vessels.

Indications

The American Heart Association and the International Liaison Committee on Resuscitation recommend open cardiac massage under certain circumstances such as penetrating cardiac arrest.[7] Authors report other indications for cardiac arrest after recent cardiac surgery and decompression of pericardial tamponade.[1][8][9] Some recommend open cardiac massage when standard advanced life support protocols do not restore spontaneous circulation within 5 to 10 minutes.[10] Other potential indications include abnormal chest wall anatomy preventing effective, closed-chest compressions, refractory ventricular fibrillation, and massive air embolism.

Contraindications

The only organic contraindication is the presence of a pulse.[6] Known patient wishes which preclude resuscitation, for example, a "do not resuscitate" order, are another contraindication.

Equipment

The necessary equipment needed to perform an emergency thoracotomy includes the following:

• Chlorhexidine gluconate or povidone iodine
• Gigli saw
• Large clamp or forceps
• Large scalpel
• Large scissors

Personnel

A cardiothoracic surgeon with experience in performing a rapid median sternotomy under 2 minutes is preferable. However, a non-specialist surgeon may also be able to perform an emergency, open thoracotomy in 2 to 3 minutes.[6] Additional staff members, including the scrub nurse, may assist.

Preparation

Typically, the need for open cardiac massage manifests during emergencies, and thus, health care professionals are exempted from informed consent in these situations. However, these health care professionals must pay careful attention and document the patient’s code status.

The patient is positioned in the supine position. The anesthesiologist or other intensive care providers should secure the airway and obtain adequate vascular access for fluid and pharmacologic administration. 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.

Technique or Treatment

Bilateral Anterior Thoracotomy Approach 

The surgeon uses a scalpel to make bilateral thoracostomies in the 5 intercostal spaces at the mid-axillary line. They then connect the thoracostomies with a deeper skin incision. Layers of the intercostal muscles and pleura are dissected as the surgeon advances towards the sternum. The surgeon then cuts through the sternum using heavy scissors, or a Gigli saw. Once they excise the sternum, they make an incision in the pericardium only if pericardial tamponade is suspected; otherwise, an intact pericardium is preferable to prevent inadvertent damage to the atria and ventricles if the heart is compressed inappropriately. The surgeon evacuates blood and any clots, if necessary, then accesses the heart.

Wise and colleagues[6] recommend a 2-handed technique for internal cardiac massage: a flat hand is placed under the posterior heart surface, and the other hand is placed on the anterior heart surface. The heart is squeezed from the apex upward at a rate of approximately 100 beats per minute. Caution must be taken not to use fingertips to compress the heart due to increased risk of myocardial injury.

A single-hand technique can also be utilized if the provider’s hand is large enough; in this approach, the provider positions straight fingers at the posterior surface of the heart near the apex and applies the thumb to the anterior surface. It is paramount that the heart remains horizontal throughout internal cardiac massage as lifting the apex may prevent venous filling. Another assistant may compress the descending aorta to maximize blood flow to the coronaries arteries and cerebral vasculature.[6]

Compression rate should adhere to the Advanced Cardiac Life Support guidelines with a rate of at least 100 beats per minute. If the return of spontaneous circulation is accomplished, sterile, saline-dampened gauze is applied to the incision, and antibiotics covering skin flora are administered. Definitive prompt surgical closure of thoracotomy, preferably by a cardiothoracic surgeon, is recommended.

Complications

The invasive nature of performing a resuscitative thoracotomy may damage surrounding nerves, blood vessels, lungs, and the heart. Specific nearby nerves include the phrenic and intercostal nerves.[1][6] Vascular injury to the intercostal, pulmonary, and internal mammary vessels may also occur.[1] Damage to the heart in the pericardium, myocardium or coronary vessels is likely due to direct manipulation of the heart. Patients who achieve successful resuscitation but require thrombolysis due to massive pulmonary embolism or stroke may be challenging because the thoracotomy incision is a relative contraindication to thrombolysis. In these cases, alternative interventions, including embolectomy and localized thrombolysis, should be considered.[1] Finally, if the patient survives, infection risk of the thoracotomy wound exists, particularly since many emergency thoracotomies are not performed with a complete aseptic technique.

Clinical Significance

Before the advent of closed-chest compressions, surgeons routinely performed open cardiac massage. Some studies have suggested that open cardiac massage may be a more efficient method of maintaining circulation during cardiac arrest compared to closed cardiac compressions. Recent data on open chest cardiopulmonary resuscitation are lacking. A study published in 1953 demonstrated a recovery rate of 28%.[11] Another study spanning 30 years demonstrated that if open cardiopulmonary resuscitation was performed within 4 minutes of cardiac arrest, recovery rates approached 58%, and these patients were neurologically intact.[12] A simple PubMed search strategy to identify trials involving comparisons between open cardiac massage and closed chest compressions only identified 1 prospective observational study within the last 5 years. In a population of patients with traumatic cardiac arrest, a prospective observational study in 2016 reported no significant improvement in end-tidal carbon dioxide or return of spontaneous circulation in a patient receiving open-chest cardiac massage following closed chest compressions compared to patients having closed chest compressions only.[2]

Another recent study was identified, which described an alternative approach to performing open cardiac massage via a transdiaphragmatic approach.[13] This case series described 6 patients who experienced cardiac arrest during laparotomy (4 liver transplantation cases, 2 trauma cases), and subsequently, open cardiac massage was performed with accessing the heart through a diaphragmatic incision. Only 3 patients regained spontaneous circulation, 2 survived during transit to the intensive care unit, and 1 survived to discharge.

Enhancing Healthcare Team Outcomes

A recent review paper by Kornhall and colleagues reviewed the available evidence on open, very closed chest compressions and proposed prior evidence that may support improved physiology and outcomes from open cardiac massage.[1] Physiologically, health care professionals know that the higher the coronary perfusion pressure, the more likely the cardiac arrest patient may achieve a return of spontaneous circulation. An animal study in Mongrel dogs performed in 2003 demonstrated a coronary perfusion pressure of 38.2 mm Hg in open cardiac compression compared to only 20.3 mm Hg with closed chest compressions.[14] Many animal studies consistently demonstrate this.[15][16] Furthermore, cerebral perfusion also concordantly improves with open cardiac massage and approaches near-normal values, whereas closed chest compressions lead to only 30% of normal cerebral blood flow.[17]

One of the primary human studies performed by Boczar and colleagues in 1995 showed that coronary perfusion pressure increased from an average of 7.3 mm Hg to 32.6 mm Hg when converting from closed-chest compressions to open chest direct cardiac compressions.[18] Furthermore, mean cardiac index values more than double with direct open compressions.[19]

Very few human trials studying outcomes of open cardiac massage have been published. 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 open cardiac massage.[20] Another study in non-traumatic, out-of-hospital cardiac arrest showed the return of spontaneous circulation in 58% of patients in the open chest compression group versus only 30% in the closed-chest compression group.[21]

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

Due to the complexity and rapidity of the required procedure, the interprofessional team must be familiar with the procedure and be prepared to act quickly. Generally, the surgeon will open the chest and gain access. The nurse may be asked to assist by performing cardiac massage, getting the paddles ready, and obtaining medications for intracardiac injection. In addition, IV fluids may need to be quickly pushed. In addition, the nurse must document the time involved, the number of shocks, the amount of medications given, and the patient's response. Even with a coordinated interprofessional approach, survival is low; however, if all members of the team are ready to act quickly, outcomes will be improved. [Level 5]