CPR-Why not?

Motivation: When I was in eighth grade, I was traveling through the Detroit Airport and saw a man ten feet from me collapse.  He just folded senseless to the ground without any preliminaries and stayed that way.  My first response was to blink my eyes to assure myself that this was real.  The unreal feeling was succeeded by an enveloping numbness.  I did nothing and gazed dumbly at the man on the ground.  Of course, if everyone had acted as I did, the man would not have received any help.  His wife cried out, and someone else must have done something (I was not noticing much).  Soon, EMS came and cleared us out.  Interestingly, nobody did CPR.

Recently, as I learned in my ED clerkship orientation, the American Heart Association reformulated the CPR guidelines to eliminate rescue breathing from the CPR algorithm for the lay person.  Although many factors went into this decision including emerging evidence that in the first few minutes chest compressions are more important than breaths, one of the key cited reasons is that removing rescue breathing may encourage more people to do CPR, which substantially increases chances of survival.  Only 20-30% of out-of-hospital cardiac arrests ever receive CPR.  I wondered, however, if people don't do CPR because they are afraid of rescue breathing or or because they are scared out of their minds - like me.  Here is an article examining this very question:

Article: CPR Training and CPR Performance: Do CPR-trained Bystanders Perform CPR?  Swor, R., et. al. Acad. Emerg. Med. 2006 (13): 596-601.  http://www.ncbi.nlm.nih.gov/pubmed/16614455?dopt=Abstract

Method: A prospective multicentered study in Southeastern Michigan in which individuals calling 911 for cardiopulmonary arrest between 1997-2003 were followed-up and interviewed.  Arrests occurring in nursing home facilities were not counted.

Results: In the study period, 868 subjects suffered arrest for whom 911 calls were made.  Of these 868 calls, 684 callers were followed-up and interviewed (78.8%).  Of the missing callers, 163 (18.8%) could not be identified or contacted while 21 refused to give permission (2.4%).  Callers were most frequently family member of the victim (69.6%).

Patient population: The patient population was predominantly male (68%) and suffered an arrest in a residential setting (80.8%).  About 17% survived to hospital admission, but only 6.6% survived to hospital discharge!

Responder characteristics: Among bystanders, 54% had received CPR training during their lifetime.  In all, CPR was started before EMS arrival in 33.6% of cases.  For bystanders, factors positively associated with starting CPR were younger age (less than 50), public location, witnessed arrest, and higher educational level. Among those who were CPR trained, only 35.1% initiated CPR.  Factors positively associated in this subgroup included public location, witnessed arrest, higher education level, and recent CPR training.  Younger age was not correlated in this population.

Reason for not doing CPR:  For those who were CPR trained, the most common causes recalled for not initiating CPR were panic (38.7%), concern about performing CPR correctly (10.8%), physical inability to do CPR (3.6%), and thoughts about potentially harming the patient (1.8%).  A significant fraction (4.3%) did not perform CPR because they thought the patient was dead.  Only four callers (1.4%) identified mouth-to-mouth resuscitation as a barrier.  None identified concern about infectious diseases.

Conclusion: This study proved once again that while arrest outside hospital has poor prognosis, many potential lives are being lost because CPR is not initiated soon enough.  What I found fascinating in this study was that even among the CPR trained, only 35% initiated CPR.  Overwhelmingly, the most common reason for not doing CPR was panic and not aversion to mouth-to-mouth resuscitation or concern about infectious diseases as commonly thought.  One point to keep in mind is that the whole study of bystanders is susceptible to the psychological bias that those not performing CPR may not want to disclose their true reasons from shame.  I also found the association between public location and bystander initiation of CPR interesting.  One reason may be that presence of more people decreases panic and incites action.

Given the high panic and anxiety surrounding such cases, I think that simplifying the CPR regimen is probably a very good thing.  If I know that when someone goes down before me I just have to kneel down and pump at 100 compressions a minute, I may be more likely to do it.  Hopefully, there will be widespread dissemination of this knowledge through posters and other public education tools.