Selected topics: prehospital careTwo deaths after prehospital use of adenosine1
Introduction
Existing prehospital studies conclude that adenosine is safe and effective despite rhythm misidentification rates of about 25% 1, 2, 3, 4, 5. Almost uniformly, these reports did not identify severe complications of adenosine use, although the studies were not randomized, patient numbers were fairly limited, and they equated rhythm conversion with beneficial outcome.
Two deaths occurred in our Emergency Medical Services (EMS) system associated with the use of adenosine. Clinical assessment determining the etiology of a rhythm may be just as important as rhythm identification and focusing on conversion to sinus rhythm.
Given the frequently erroneous use of adenosine, the stability of most supraventricular tachycardia (SVT) patients in the field, and an effective option of electrical cardioversion for unstable patients, an argument can be made for re-evaluating the risk/benefit ratio of field adenosine use.
Section snippets
Case 1
A 48-year-old man awoke from sleep just after 3:00 AM with severe dyspnea. Previously well, he had no significant medical history, took no medications, and had no allergies. He was reportedly alert but anxious with paresthesias in his hands and, although there was no chest discomfort, his breathing was labored. Skin was cool and moist and said to be ashen-colored. The blood pressure was 92 mm Hg by palpation, pulse 150–190 beats/min, and respiratory rate 40 breaths/min. His electrocardiogram
Discussion
These patients had underlying, life-threatening clinical conditions that probably led to their deaths; nevertheless, there was a striking temporal relationship to the use of adenosine. Adenosine usually results in brief asystole or bradycardia, and neither of these compromised patients may have tolerated the momentary drop in cardiac output. Both likely suffered from right ventricular strain and were more difficult to resuscitate than a patient who simply experiences a postadenosine dysrhythmia.
Conclusions
The two deaths in this report should change the perceived risk/benefit ratio of adenosine use. Given transport intervals in most EMS systems, the frequency of rhythm conversion in this setting (about 63%), and the potential threat to the patient posed by the dysrhythmia, randomized clinical trials would be appropriate. One question would be how to weigh the value of reducing a patient’s symptomatic interval even if there is no immediate danger. At the least, EMS systems should audit rhythm
References (6)
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Adenosine for the prehospital treatment of paroxysmal supraventricular tachycardia
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Intravenous adenosine as first-line prehospital management of narrow-complex tachycardias by EMS personnel without direct physician control
Am J Emerg Med
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Effect of adenosine on the management of supraventricular tachycardia by urban paramedics
Ann Emerg Med
(1995)
Cited by (13)
Pulmonary edema postcardioversion: A potential calcium signalling problem
2006, Canadian Journal of CardiologyAccuracy of Arrhythmia Recognition in Paramedic Treatment of Paroxysmal Supraventricular Tachycardia: A Ten-year Review
2004, Prehospital Emergency CareDysrhythmia's everest
2001, Journal of Emergency MedicineFactors Influencing Medication Errors in the Prehospital Paramedic Environment: A Mixed Method Systematic Review
2023, Prehospital Emergency Care
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Selected Topics: Prehospital Care is coordinated by Peter Pons, md, of Denver General Hospital, Denver, Colorado