2012- October R3 Journal Review
Goldberger Z, et al. Duration of resuscitation efforts and survival after in-hospital cardiac arrest: an observational study. The Lancet. Published online September 5, 2012 http://dx.doi.org/10.1016/S0140-6736(12)60862-9. This was a prospective cohort study of patients who underwent an index in-hospital cardiac arrest at facilities participating in the National Registry of Cardiopulmonary Resuscitation. The definition of cardiac arrest used was unresponsiveness, apnea, and absence of a central palpable pulse. Patients undergoing arrest in the Emergency Department, operating rooms, procedure areas such as cath labs, and rehabilitation areas were excluded. The primary end-points were return of spontaneous circulation and survival to hospital discharge. A secondary end-point of neurologic status at discharge was rated on a 1-5 scale with scores of 1 or 2 signifying good neurologic status. The goal of this study was to evaluate the effect of the length of resuscitation attempts on these end-points.
A total of 93,535 arrests occurred at 537 hospitals of these 64,339 cases were included in the analysis. A total of 48.5% of patients had return of spontaneous circulation with 15.4 percent surviving to hospital discharge. Of the patients who survived to hospital discharge, 80.6% had a good neurologic outcome. When compared on length of resuscitation, those with return of circulation had an average resuscitation time of 12 minutes compared to 20 minutes for those that didn’t. A secondary analysis was performed which stratified hospitals based on the average length of their resuscitation attempts. In this analysis, they found that there was increased survival in the quartile of hospitals with the longest resuscitations compared to those with the shortest. This was most apparent when dealing with asystolic and PEA arrests. When looking strictly at neurologic outcome there was no difference between the hospitals.
In their discussion the authors attempt to correlate longer resuscitations with survival. This was not readily apparent in their initial data. On initial review of the data it appears to show what has been previously apparent, namely that those patients who are going to have good outcomes are most likely to have earlier return of spontaneous circulation. It does, however, emphasize the importance of evaluating for reversible causes, particularly in the more complex asystolic and PEA arrests. These are the arrests that may have a more delayed return of spontaneous circulation and may benefit from a prolonged resuscitation, although it may not result in good neurologic outcome.
Le May MR, et al. Reduction in mortality as a result of direct transport from the field to a receiving center for primary percutaneous coronary intervention. Journal of the American College of Cardiology. 2012 Oct 2; 60(14):1223-30. This study used data from the prospective STEMI registry at the University of Ottawa Heart Institute to evaluate outcomes of patients referred for primary percutaneous coronary intervention (PCI) between May 1, 2005 and April 30, 2011. The study compared outcomes for STEMI patients referred directly to the PCI center versus those who had been transported to a non-PCI center before eventual referral to the study PCI site. The primary outcome measure was all cause mortality at 180 days. In total, 1389 consecutive patients with STEMI were assessed by pre-hospital providers and referred for primary PCI. 822 (59.2%) were taken directly from the field to a tertiary PCI center while 40.8% were transported to a non-PCI facility first. The decision to taken patients to a non-PCI center was largely based on pre-hospital EKG not meeting the pre-established STEMI criteria, or due to an inability of paramedic responders to interpret the EKG. Patients who presented in cardiogenic shock and patients who were comatose following resuscitation were excluded because these patients were transported to the nearest ED. Patients who self-transported to the ED were also excluded. Coronary angiography was performed on 99.1% of all patients. Primary PCI was performed on 93.1% of patients referred directly from the field versus 90.3% of patients transferred from a non-PCI center. The median door-to-balloon time was shorter for patients transported directly from the field (66 min) as compared to the non-PCI referral group (117 min). A door-to-balloon time of < 90 minutes was achieved in 82.6% of patients transferred directly from the field versus in 20.8% of patients in the non-PCI-capable hospital group. Follow-up was available in 1329 patients (96%) at 180 days. The primary outcome of all-cause mortality at 180 days occurred in 5.0% of patients in the field to PCI group and in 11.5% of patients in the group transported to the non-PCI center (p < 0.0001). This study supports the implementation of STEMI receiving centers to reduce time delay to primary PCI. This finding further supports the ACC/AHA STEMI guidelines established in 2009 advocating the establishment of networks reducing the time to PCI. This study is limited in the fact that it was not a randomized trial. Further limitations include the fact that these results may not apply to regions where trained paramedics are not able to establish STEMI in the pre-hospital setting.