By: Dr. Geoffrey Modest
So, I happened to peruse the last few issues of the journal Resuscitation on my coffee table and found a couple of interesting articles about CPR… in any event, here are the articles.
1. A Swedish study looked at 222 patients who underwent unsuccessful CPR and had autopsies done (see doi.org/10.1016/j.resuscitation.2014.09.017). of these 83 had manual CPR and 139 had mechanical with a LUCAS device (a Swedish mechanical device for doing chest compression, which in some studies achieved better circulation than manual compression). Results:
–75.9% of those in manual CPR and 91.4% with mechanical had CPR-related injuries
–54.2% with manual and 58.3% had sternal factures
–64.6% with manual and 78.8% with mechanical had at least one rib fracture (signif difference at p=0.02), with median numbers of ribs fractured at 7 in the manual and 6 in the mechanical groups.
–None of these injuries were considered to be cause of death
–Subgroups: all 46 patients with signs of osteoporosis had rib fractures, 82.6% with sternal fractures; and (perhaps related) older people tended to have more traumatic injury.
–(but this is a select group of nonsurvivors)
2. Another Resuscitation journal article looked at in-hospital cardiac arrest survivors to assess their memories in a prospective multi-center study (see doi.org/10.1016/j.resuscitation.2014.09.004). Results:
–330 survivors of 2060 cardiac arrests (16%), of whom 140 were deemed fit to interview (not clear why so few?? The listed reasons were that they died after discharge, were not deemed suitable by their MD, or did not respond to the invitation to be included. But there is a likely significant selection bias in the 140 included)
–46% had memories with 7 cognitive themes: fear; seeing animals/plants; bright light; violence/persecution, e.g. being dragged through deep water; deja-vu; family being present or talking with them; recalling events post resuscitation, eg a tooth coming out after removing the endotrach tube.
–9% had “near-death experiences”
–2% recalled seeing/hearing actual events related to the resuscitation
So, what does this all mean?? I think CPR is a challenging conversation with patients, part of the issue being that the popular culture depicts it deceptively as typically successful and with really good outcomes. For example, a study done assessing the survival in reality-like medical TV shows from 1994-1995 (ER, Chicago Hope, Rescue 911) found that 75% survived CPR and 2/3 were discharged with full brain function (thanks, Jenny Siegel). It probably makes sense that patients have a more appropriate, medically grounded understanding. And the real outcome data are actually pretty bad. Out-of-hospital survival rates are in the 1-6% range (a 2012 study of adults found that only 2% of adults who collapse on the street and got CPR achieve a full recovery), perhaps in the 5-10% when done by EMS types. In-hospital, it is 15% or so of patients who survive to discharge (and many of these patients are not exactly restored to their former health…). These studies above highlight another component of the issue. A very high percentage develop rib fractures and other traumatic injuries (one concern about the poor survival rate in hospitals is that studies have found that trained health care providers pretty consistently do not do CPR correctly, though perhaps the higher rib fracture rate with the mechanical device attests not only to its improved achieved circulation but also to its actually really compressing the chest…..). And there are clearly documented psych effects (PTSD) along with some pretty miserable memories or associations. A study done in 1983 (which perhaps dates me a tad) looked at factors influencing survival post in-hospital cardiac arrest (e.g., terrible if have underlying diagnosis of pneumonia, sepsis, poor urine output/high BUN, prior fitness, or if resuscitation taking >30 minutes). But of significant interest to me was that of the 41 survivors (14% of those getting CPR and surviving to discharge), 100% reported a functional status decrease and 42% stated that they would NOT choose to be resuscitated in the future (up to 47% when asked 6 months later), see (cpr bedell nejm 1983 in dropbox, or N Engl J Med 1983; 309: 569-76). So, the patient may well be bringing to the discussion of CPR very unrealistic expectations, reinforced by the ambient culture. In order to get a real sense of what the patient wants, seems to me that we as clinicians should outline several of the issues above: the survival likelihood overall is not great (though of course some can be expected to do better than others: my guess is that the stats are better for the reasonably healthy 32 year old who arrests on the table getting electrophysiological studies), that there is a really high incidence of rib/sternal fractures with chest compressions (esp. if older, osteoporotic), and that patients rarely come back to their prior state (with cognitive, psychiatric and medical issues). Then the patient can choose more knowledgeably.