CPR: Longer may be better
Hospitalists may be stopping resuscitation too soon
Keywords: Research finds that some patients benefit from longer CPR efforts
by Deborah Gesensway
Published in the November 2012 issue of Today's Hospitalist
IF YOU HAVE A HUNCH that a hospitalized patient in cardiac arrest might benefit from a few more minutes of resuscitation, keep going. According to the lead author of a new study that looked at how the duration of inpatient resuscitation efforts affects survival, that's the lesson hospitalists should take away from the research.
"The message is not that longer is better overall," says Zachary D. Goldberger, MD, assistant professor of medicine at the University of Washington and a cardiologist at Seattle's Harborview Medical Center. "But the research suggests that longer
efforts may benefit some patients." The observational study was published in the Sept. 5, 2012, issue of The Lancet.
|"Additional minutes can have substantial implications in critically ill patients."|
–Zachary D. Goldberger, MD
Harborview Medical Center
Obviously, Dr. Goldberger points out, there are "patients who will not survive the resuscitation, and if they do, they may not have a meaningful recovery. But in some patients, the decision to stop a resuscitative effort is less clear."
While the research in no way supports continuing futile care, "the overall message is clearly a non-trivial amount of patients need more than 30 minutes." And although the study found that the duration of resuscitation efforts varies substantially from hospital to hospital, "attempts in most patients are rarely extended that long."
The study looked at more than 64,000 patients who had experienced cardiac arrest in 435 U.S. hospitals between 2000 and 2008. The research did not, however, shed light on exactly how long resuscitation efforts should last. "There is no magic number," Dr. Goldberger says.
Not much of a time difference
Dr. Goldberger and his team used American Heart Association registry data to look at several factors related to inpatient resuscitation. To gauge how long hospitals would attempt to resuscitate patients, the research team looked specifically at an unusual subgroup: patients who didn't survive a cardiac arrest that happened in the hospital.
The authors analyzed how long resuscitation had been tried on those patients before being deemed unsuccessful. (They studied nonsurvivors rather than survivors because resuscitation is stopped immediately when someone revives. Therefore, findings on the duration of successful attempts will always skew to the shorter end of the curve if survivors' resuscitation-duration data are included.)
The team also matched survival rates to duration—and found that patients were more likely to survive when their cardiac arrest happened at hospitals that on average spent more time trying to resuscitate nonsurvivors. That was compared to patients who arrested at hospitals that resuscitated nonsurvivors for shorter median amounts of time.
But the time difference outlined in the study wasn't substantial, Dr. Goldberger notes. Hospitals that fell into the quartile with the longest resuscitation times attempted resuscitating patients for only nine minutes longer on average than hospitals in the quartile with the least amount of time: 25 minutes compared to 16 minutes. Patients at hospitals with longer duration times, according to the article, "had a higher likelihood of return of spontaneous circulation and survival to discharge than did those at hospitals with shorter median resuscitation durations."
Moreover, the study found that people who ultimately survived their arrest—but only after prolonged resuscitation—didn't suffer worse neurological effects than people who came back more quickly.
"If someone came to me and said, 'Great, you saved all these lives, but they all likely have no chance of a neurological recovery,' I would answer, 'not necessarily,' " Dr. Goldberger says. Although the investigators had neurologic data available for only a small sample of their cohort, their results showed that "there doesn't seem to be a detriment in their neurological function with longer effort, if patients survive."
The research raises important questions, says Dr. Goldberger: Is duration of resuscitation a marker for either better resuscitation technique overall or for more comprehensive care?
And do hospitals that tend to resuscitate patients longer do other things better that may contribute to improved survival? Those could include systematically following clinical guidelines, doing good quality compressions, having better team coordination or leadership, and having an overall culture that stresses a more aggressive approach to resuscitation. "Duration," says Dr. Goldberger, "may be only part of it."
While hospitals that tried resuscitation the longest were 12% more likely to achieve spontaneous circulation when all patients were included in the analysis, the effect was greater for some subgroups. Those included patients for whom the initial rhythms were pulseless electrical activity or asystole, which generally have a poorer prognosis.
As Dr. Goldberger explains, "these patients tend to have underlying causes for their cardiac arrest that can be reversible." And because you can't defibrillate pulseless electrical activity or asystole, "those patients need more medicines, more compressions and probably more time."
In the U.S., about 200,000 hospitalized patients experience cardiac arrest every year, and only half survive the arrest. An even smaller percentage—20%—survives to discharge. Conventional wisdom, meanwhile, holds that prolonged resuscitation efforts "provide no additional benefit because if patients don't survive early on, then their overall prognosis is poor," says Dr. Goldberger.
A bigger window
The authors also learned that most people who came back from their arrest did so in less than 30 minutes. But they were surprised by the proportion of patients who revived only after more resuscitation.
"We found that at least 15% of patients needed a bit longer," says Dr. Goldberger. When you compare that to the information about nonsurvivors, which showed that resuscitation had been stopped after 15 minutes in a third of patients and within 30 minutes for about 75%, he explains, "it suggests there is a substantial opportunity for improvement."
The study could not offer information about which specific patients in cardiac arrest may need a longer resuscitation attempt. "That has to come down to the clinical judgment of the physician at the bedside," he says.
Dr. Goldberger hopes that hospitalists and others involved in in-hospital resuscitation will think carefully before stopping, particularly if they have been trying to resuscitate a patient for only 15 or 20 minutes.
He also notes that he and his team did not do a cost-effectiveness analysis. But "once you invest all the resources that are needed to do resuscitation—you gather all the housestaff and hospitalists, you open the crash cart, you get out all the meds, you start compressions—asking doctors to stand for 10 more minutes and continue may not be wasting more resources," he points out. "Those additional minutes can have substantial implications in critically ill patients."
Deborah Gesensway is a freelance writer who covers U.S. health care from Toronto.