NEW ORLEANS — Implementation of an organized transfer protocol has yielded proof that moving high-risk ST-segment elevation myocardial infarction patients—even those who are in cardiogenic shock—from community hospitals for percutaneous coronary intervention is safe.
Primary percutaneous coronary intervention (PCI) is the treatment of choice for ST-elevation MI if done at experienced centers in a timely fashion. Unfortunately, in the United States, only 25% of hospitals have PCI capability, which makes transferring these patients for PCI essential most of the time, Dr. David M. Larson, of the Ridgeview Medical Center, Waconia, Minn., and the Minneapolis Heart Institute, said at the annual meeting of the American College of Emergency Physicians.
No deaths occurred during transfer of 746 consecutive ST-elevation MI (STEMI) patients for PCI using the Level 1 Heart Attack program, a standardized transfer protocol developed by a team of cardiologists and emergency physicians from the Minneapolis Heart Institute, Dr. Larson said.
The patients were transferred from the emergency departments of 28 rural and community hospitals, at distances ranging from 23 to 210 miles, to Abbott Northwestern Hospital in Minneapolis. Two-thirds of the patients were transferred by helicopter and the rest were moved by ground ambulance, with median transport times of 28 and 32 minutes, respectively.
The median door-to-balloon time was 97 minutes for the hospitals that were up to 70 miles away from Abbott Northwestern, and 117 minutes for the hospitals that were up to 210 miles away. The national door-to-balloon time average for patients receiving ad hoc transfer for PCI is 180 minutes, Dr. Larson said.
“Our times are excellent and show that transferring STEMI patients is definitely doable, as long as you have an organized approach.”
All patients were very high risk, with ST elevation or new left bundle branch block. Seventeen percent were aged 80 years or older, 14% had cardiogenic shock, 10% had a cardiac arrest before their transfer for PCI, and 46% had a Thrombolysis in Myocardial Infarction (TIMI) risk score of at least 4.
A pretransfer fibrinolytic was given to 252 patients (33.8%), and endotracheal intubation was performed pretransfer in 34 patients (4.6%) and during transfer in 5 (0.7%).
During transfer, 12 patients experienced cardiopulmonary arrest but all were resuscitated, with return of spontaneous circulation. However, two of these patients, who had severe cardiogenic shock, died during angiography, and one died from anoxic brain injury. The remaining nine patients were discharged neurologically intact, Dr. Larson said.
An organized, integrated system involving collaboration among cardiology, emergency medicine, nursing, and prehospital and other ancillary medical personnel is required to achieve the recommended door-to-balloon times for patients with STEMI who are transferred for primary PCI (see above article), Dr. Larson said.
This requires the development of a standardized protocol that empowers the emergency physician to make key decisions, he added.
“One of the key features of our program is that we allow the emergency department physicians to make the decision to activate the cath lab, so we don't have to wait until a cardiologist calls back and consults us. As soon as we make one phone call, the cath lab team will be waiting for the patient when he or she arrives. This really empowers the physician,” he said.
Additionally, each hospital should have prearranged transfer agreements in place with local ambulance and helicopter companies.
Also, patients should be taken immediately to the cath lab and not undergo reevaluation in the emergency department upon arrival at the PCI center, Dr. Larson said.
A patient being transferred under the Level 1 Heart Attack protocol is unloaded at Abbott Northwestern Hospital. The door-to-balloon time for patients transferred from up to 70 miles away from Abbot is 97 minutes, about half the national average. Barbara Unger