What is the proper procedure for cardiopulmonary resuscitation (CPR) in a patient with an open chest after surgery?

CPR on Open Chest After Surgery

For cardiac arrest after open heart surgery, immediately initiate external chest compressions if emergency resternotomy is not available within 1 minute, but proceed to early resternotomy (within 5 minutes) if initial defibrillation or pacing fails, as open-chest CPR generates superior hemodynamics with cardiac index doubling from 0.6 to 1.3 L/min/m² compared to external compressions. 1, 2

Initial Response Algorithm (First 60 Seconds)

The approach differs dramatically based on the presenting rhythm:

For Witnessed VF/VT Arrest

• Perform immediate defibrillation as the first intervention 1
• VF/VT occurs in 25-50% of post-cardiac surgery arrests, with first shock success rates exceeding 90% 3
• If defibrillation unsuccessful within 1 minute, immediately begin CPR 1
• This prioritization avoids the morbidity of chest compressions or resternotomy when a single shock may restore circulation 3

For Asystole or Bradycardic Arrest

• Attempt immediate pacing if epicardial wires are already in place 1
• Use available hemodynamic monitoring to confirm myocardial capture and adequate cardiac function 3
• If pacing unsuccessful within 1 minute, initiate standard CPR 1

For PEA or Unwitnessed Arrest

• Begin external chest compressions immediately while rapidly identifying reversible causes 1
• Despite case reports of cardiac damage from external compressions, the risk is far outweighed by certain death without perfusion 3

Critical Reversible Causes to Address Simultaneously

Post-cardiac surgery arrests have specific mechanical etiologies requiring urgent identification:

• Cardiac tamponade (most common mechanical cause) 1
• Tension pneumothorax 1
• Graft occlusion (coronary or vascular) 1
• New valve dysfunction 3
• Hemorrhage 1

Resternotomy Decision Point (3-5 Minutes)

The Society of Thoracic Surgeons recommends resternotomy as a standard part of resuscitation protocols for at least 10 days after surgery. 3, 4

Indications for Emergency Resternotomy

• Failure of initial defibrillation or pacing within 1 minute 1
• Suspected mechanical cause (tamponade, bleeding, graft occlusion) 1
• Refractory arrest despite standard ACLS measures 4

Critical Success Factors

• Must be performed by experienced providers 3, 4
• Must occur in appropriately staffed and equipped ICU 3, 4
• Good outcomes observed with rapid resternotomy protocols when these conditions are met 3
• Resternotomy performed outside the ICU results in poor outcomes 3

Hemodynamic Superiority of Open-Chest CPR

• Cardiac index increases from 0.6 L/min/m² (closed-chest) to 1.3 L/min/m² or higher (open-chest) 2
• Coronary perfusion pressure more than doubles with direct cardiac compression 2
• Superior forward blood flow and return of spontaneous circulation documented 4

Open-Chest CPR Technique

Direct cardiac compression is performed using either thumb-and-fingers technique or palm against sternum with extended fingers. 4

• Access through existing sternotomy (post-cardiac surgery) or thoracotomy through 5th left intercostal space 4
• Generates superior coronary perfusion pressure compared to external compressions 4

Ventilation Management During Resuscitation

Use lower tidal volumes, lower respiratory rates, and increased expiratory time to minimize auto-PEEP and barotrauma. 1, 5

• Evaluate for tension pneumothorax as a rare but life-threatening complication 1
• Brief disconnection from ventilator or pause in bag-mask ventilation with thoracic compression may relieve hyperinflation 1
• Target arterial oxygen saturation ≥94% but avoid hyperoxia 5

Mechanical Circulatory Support for Refractory Cases

For patients refractory to standard resuscitation including open-chest CPR, mechanical circulatory support (ECMO or cardiopulmonary bypass) may improve outcomes when the etiology is potentially reversible. 3, 1, 4

• Multiple case series demonstrate potential benefit, though no RCTs exist 3
• Consider when suspected cause could be corrected during limited period of mechanical support 1
• Represents evolving advanced resuscitative technique in modern cardiac surgery centers 6

Common Pitfalls to Avoid

• Delaying resternotomy beyond 5 minutes when initial measures fail 1, 7
• Performing resternotomy outside the ICU without experienced personnel and equipment 3
• Failure to recognize mechanical causes requiring surgical intervention rather than prolonged medical resuscitation 1
• Excessive tidal volumes causing auto-PEEP and impeding venous return 1
• Continuing external compressions when open-chest CPR is feasible, as this provides inferior hemodynamics 2

Context-Specific Considerations

Cardiac arrest occurs in 1-8% of cardiac surgery cases, typically in highly monitored ICU settings with trained staff available 3, 7. This unique environment—with existing monitoring, vascular access, and surgical expertise—creates an opportunity for survival rates substantially higher than standard cardiac arrest when protocol deviations from traditional ACLS are implemented 7.

The landscape continues evolving with minimally invasive cardiac surgery (lateral thoracotomy, mini-sternotomy), requiring personnel to expeditiously identify the most appropriate rescue strategy for each patient's specific surgical approach 6.