July 11, 2008–When combined with the conventional cardiopulmonary resuscitation (CPR), extracorporeal life support (ELS) can double the survival of adult hospital patients in comparison with CPR alone. These results were released on July 7, 2008 in The Lancet.
Myocardial infarction, or heart attack, occurs when blood flow to the beating heart is restricted. This is related but not equivalent to sudden cardiac arrest (SCA), which is a sudden halt in all blood flow because the heart does not contract properly. Even when CPR is introduced, sudden cardiac arrest has a low survival rate, which has not changed significantly since 1993. Previous studies investigating the relationship between CPR and survival rates have shown that, once CPR has been performed for 10 minutes, survival rates drop significantly, and even more if this exceeds 30 minutes.
Another method of support for cardiac arrest patients is ELS, which acts via insertion of a catheter into the femoral vein and artery in the leg. In the process, blood travels out through this catheter by way of a pump, heat-exchanger, and oxygenator before returning to the body, prepared to reenter the body with bound oxygen. Using ELS has previously shown positive results in cardiac arrest patients. It enhances the coronary blood flow, helping keep heart tissue alive, which can reduce the time needed before independent circulation can occur. Additionally, ELS maintains blood flow to other organs, thus preventing further dysfunction and decreasing later morbidity. Finally, while supported using ELS, the underlying cause of the arrest can be diagnosed, assisting with the treatment of this condition and thus the eventual return of the patient to a normal state.
To investigate the effects of CPR and ELS on the survival of SCA patients, Yih- Sharng Chen, MD, and Jou-Wei Lin, MD, National Taiwan University Hospital, Taipei, Taiwan, and colleagues performed a three-year study examining patients between the ages of 18 and 75 years who had experienced in-hospital cardiac arrest of cardiac origin. In this group, 113 patients had been treated with only CPR for more than 10 minutes, while 59 had been treated with both ELS and CPR.
The patients who received both measures had a better survival rates to discharge, better 30=day survival and better 1-year survival than patients who received only conventional CPR. For each of these endpoints, patients who received ELS were approximately half as likely to die as those receiving only CPR.
The authors conclude: "Extracorporeal CPR had a short-term and long-term survival benefit over conventional CPR in patients with in-hospital cardiac arrest of cardiac origin."
Reference: Cardiopulmonary resuscitation with assisted extracorporeal life-support versus conventional cardiopulmonary resuscitation in adults with in-hospital cardiac arrest: an observational study and propensity analysis
Lancet, July 7, 2008 Click Here For Journal
- Anna Sophia McKenney, Medical News Today