Prehospital consideration of sildenafil-nitrate interactions

Objective. To determine whether paramedics and on-line physicians screen patients for use of sildenafil citrate (Viagra) prior to prehospital administration of nitrates. Methods. A prospective, observational study was performed over a one-month period in three EMS systems. Consecutive radio communications between on-line physicians and paramedics concerning male patients with cardiac complaints were monitored. Investigators observed the frequency with which on-line physicians screened for sildenafil use prior to ordering nitrates. After observation of the radio communications was completed, a written survey was distributed to all paramedics in the three EMS systems. Results. Seventy-six physician-paramedic interactions were monitored. Nitrates were ordered by on-line physicians in 56 cases. No paramedic reported sildenafil use/nonuse, and no on-line physician inquired about the patient's potential use of the drug. Only half of the surveyed paramedics reported that they routinely screen for sildenafil use, and approximately a fourth reported that its use would not alter their management of chest pain patients. Conclusion. In this study, on-line physicians in three EMS settings did not screen for sildenafil use prior to ordering nitrates. While some paramedics do screen for sildenafil use, practice patterns among paramedics in these three systems were inconsistent.