The National Registry of CPR collects data from in-hospital resuscitation events in more than 500 participating hospitals in the United States. In the latest publication, "Survival From In-Hospital Cardiac Arrest During Nights and Weekends"  the authors evaluated survival rates over a 7 year period for adults in-hospital cardiac arrest based on arrest time of day and day of week.

As expected the results showed that survival rates were worse during nights and weekends. The biggest areas of concern being operating room/postanesthesia care unit and the interventional catheterization laboratory. The differential did not hold true for the emergency or trauma units.

The authors believe that there are many factors that contribute to the decline at night and on the weekends.

 Some factors are:

 - Physicians perform psychomotor tasks less proficiently at night,

-  experienced workers often times do not get scheduled on night shifts, 

-  and fewer visitors means that the likelihood of detecting deterioration in an unmonitored patient is much less.

These are just a few reasons that are mentioned. The NRCPR believes that these stats can be fixed with additional training, such as mock codes and cardiac resuscitation simulation. Also, with the addition of schedule changes taken into account alternating weekends and nights to boost proficiency.

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