by Isam Mina | Edited by Kiyan Daneshvar
The human blood system consists of the pulmonary and systemic circulations with blood flow being regulated by an electrical stimulus. Occasionally, this electrical regulation can be faulty and cause an arrythmia eventually leading to a cardiac arrest. To mitigate the neurological effects of a cardiac arrest, the function of the heart must be artificially simulated through a process known as cardiopulmonary resuscitation (CPR). Fundamentally, CPR maintains blood flow to the organs of the body via chest compressions.
Commonly, CPR has been associated with a particular compression technique referred to as active compression-decompression CPR (ACD-CPR). This technique refers to the compression of the sternum using the palm of one’s hand. More precisely, it involves a repeated cycle of thirty chest compressions and two breaths.
This aforementioned technique has evolved into the face of basic life support. Effective as it is, its dominance in the first aid field may be challenged by the emergence of an alternative technique by the name of interposed abdominal compressions CPR (IAC-CPR).
A three-rescuer technique, IAC-CPR includes the compression mechanisms involved in ACD-CPR, in addition to abdominal compressions between the xiphoid process and the umbilicus alternately performed with chest compressions.
According to Diana M. Cave, a former regional account manager who was involved in implementing programs with the American Heart Association (AHA), “IAC-CPR increases diastolic aortic pressure and venous return, resulting in improved coronary perfusion pressure”.9 This is due to abdominal compressions’ effect in (1) increasing intrathoracic pressure and (2) charging the intrathoracic compliance to prepare for the coming chest compression.
There have been several clinical studies and trials conducted to evaluate the efficiency of IAC-CPR in comparison to ACD-CPR. Most notable are the two studies conducted by Dr. Jeffrey Sack, a former instructor in “Advanced Life Support” at the AHA, and Dr. Michael Kesselbrenner, a specialist in interventional cardiology.
Results from the first randomized in-hospital study of 143 patients who experienced a cardiac arrest showed that the overall rate of return of spontaneous circulation (ROSC) in patients who received IAC-CPR was 49%, which was greater than the ROSC of patients who received standard CPR, which was 28%. Results from the other in-hospital trial of patients who experienced cardiac arrest yielded results further proving that the ROSC and patient survival rate of patients who experienced IAC-CPR (51% and 25% respectively), were greater than the ROSC and patient survival rate of patients who experienced standard CPR (27% and 7% respectively).
On the other hand, one in-hospital study conducted by J. R. Mateer et al. using the Milwaukee County Paramedic System showed no significant improvement in the survival rate of patients who received IAC-CPR (28%) and that of patients who received standard CPR (31%).
By no means is this article saying that IAC-CPR is determinedly a more effective technique than ACD-CPR. However, dismissing the promise exhibited by this technique would not be in the best interest of our public health system. With that being said, the implications of integrating a more effective CPR technique can be far-reaching and all-encompassing, improving our ability to deal with injuries that do not necessarily need to be fatal. In shifting between these techniques, we will need to rely on the stability of the public health system and its capability of spreading awareness and conducting efficient first aid training.