Direct cardiac massage without major thoracotomy: feasibility and systemic blood flow

Area of Science:

• Cardiovascular Physiology
• Emergency Medicine
• Surgical Innovation

Background:

• Open-chest cardiac massage (OC-CM) offers superior hemodynamics but requires thoracotomy.
• Minimally-invasive direct cardiac massage (MID-CM) was developed to avoid major thoracic incisions.
• This pilot study assesses the feasibility and efficacy of MID-CM.

Purpose of the Study:

• To test the technical feasibility of effective direct cardiac massage via a small thoracic incision.
• To compare systemic blood flow and metabolic indicators between MID-CM and OC-CM.

Main Methods:

• Twelve swine underwent induced ventricular fibrillation and resuscitation.
• Groups received either bimanual OC-CM (N=6) or MID-CM (N=6) for 30 minutes.
• Hemodynamic and metabolic measurements were recorded at baseline and at 10, 20, and 30 minutes.

Main Results:

• Both MID-CM and OC-CM reduced aortic blood pressure and cardiac index from baseline.
• No significant differences in systemic blood pressure, pulmonary artery pressure, or cardiac index were observed between MID-CM and OC-CM.
• Metabolic indices, including mixed venous O2 saturation and arterial pH, showed similar decreases in both groups over time.

Conclusions:

• MID-CM is technically feasible and achieves comparable hemodynamic and metabolic results to OC-CM in swine.
• MID-CM represents a potential alternative to OC-CM, avoiding the need for a major thoracotomy.
• Further research is warranted to validate these findings in clinical settings.