New Test for Determining Futility of CPR

The Wall Street Journal reports that the "capnograph," which measures carbon dioxide being expelled from the mouth of the patient, can "tell rescuers when further efforts at cardiopulmonary resuscitation, or CPR, are futile or whether they should be continued."  The capnograph records CO2 pressure in milligrams of mercury. If the maximum CO2 pressure achieved during 20 minutes of CPR is 14 or less, resuscitation is almost certainly futile. If the level is above about 25, you need to keep working at it.