Cardiac & Resuscitation, Patient Care

Study Analyzes whether Gender Affects Cardiac Care

Issue 5 and Volume 37.

Aguilar SA, Patel M, Castillo E, et al. Gender differences in scene time, transport time, and total scene to hospital arrival time determined by the use of a prehospital electrocardiogram in patients with complaint of chest pain. J Emerg Med. 2012; Feb 15. [Epub ahead of print].

These authors retrospectively analyzed San Diego EMS charts, measuring the effect of prehospital 12-lead ECGs on scene times. Out of 21,742 chest pain calls, no significant scene time increases or differences were found between patients with and without ST-elevation myocardial infarction (STEMI). This is nothing new; this has been studied many times. The researchers did, however, find that in STEMI cases, male patients had an average of 17-minute scene times vs. females, who had 20-minute scene times. This delay is then projected to a possible increase of 0.25–1.6% greater mortality.

This study adds to a growing body of literature showing that women experiencing acute coronary syndromes receive delayed diagnosis and care. Possible explanations could include atypical presentations, delayed symptoms or comorbidities. I’ll add my own observation that performing prehospital 12-leads on women involves a certain need for tact and social privacy that may cause a delay. In any case, now that we are aware of it … let’s all try to speed up identification and care for women having STEMIs.

Waldron R, Finalle C, Tsang J, et al. Effect of gender on prehospital refusal of medical aid. J Emerg Med. 2012; Feb 9. [Epub ahead of print].

It shouldn’t be any news that patient refusals often end in adverse outcomes and continue to be a problem for EMS. I applaud these authors for discovering a new angle to this issue. This New York City project retrospectively reviewed one year’s worth of patient-care reports for a single hospital-based ambulance service. The staff at this service is made up of 82 EMTs and paramedics, with 67 men (82%) and 15 women (18%). Out of 19,455 total patient encounters, 238 refusals were documented. (If this is accurate, congratulations are due on a 1.2% refusal rate. This is one of the lowest ever reported in recent literature).

Although most of the refusals came during the evening tour, no correlation was found to it being in the beginning or near the end of the crew’s shift. The authors did, however, discover that crews composed of two male providers were four times more likely to have an encounter end in a refusal when compared to a crew that had one or both female crew members.

In the discussion, the authors note that differences in communication styles between genders may lead to perceptions of behaviors demonstrating greater care by female healthcare providers.

Treatment of Seizures
Silbergleit R, Durkalski V, Lowenstein D, et al. Intramuscular versus intravenous therapy for prehospital status epilepticus. N Engl J Med. 2012;366(7):591–600.

The much anticipated results from the Rapid Anticonvulsant Medication Prior to Arrival Trial (RAMPART) study were published in February in the New England Journal of Medicine. The study’s main objective was to show that prehospital intramuscular (IM) midazolam (10 mg) was just as good as the in-hospital standard of care: IV lorazepam (4 mg) for status epilepticus.

Because lorazepam has a short shelf life when it’s stored un-refrigerated, most EMS systems find it costly and impractical to carry. Midazolam is widely used, but it hasn’t been studied well in the prehospital environment. This landmark prehospital study will likely be remembered more for its rigorous scientific methods rather than for the actual results. It’s a great example of the “gold standard” of research: double-blinded, prospective, randomized studies with great follow through to hospital discharge. The authors used some innovative and groundbreaking strategies to overcome the usual hurdles that make prehospital research so difficult.

First, the details: RAMPART involved 4,314 paramedics from 33 EMS agencies and 79 receiving hospitals across the U.S. They enrolled 893 patients and randomly assigned them to either the midazolam or the lorazepam group. Neither the patient, the paramedic nor the receiving hospital were aware of what medication was administered. The results: IM midazolam stopped the seizure before hospital arrival 73.4% of the time while IV lorazepam was 63.4% effective. They conclude that midazolam is safe and effective.

Although IV lorazepam had a more rapid onset, establishing an IV in a seizing patient was widely variable. Thanks to accurate time stamps, this study clearly proves that auto-injectors allow for rapid administration of medications and faster seizure cessation—even if the IM medication is slower to take effect. Patients who received midazolam were also hospitalized less often and required fewer intubations.

Now for the unique components that make this a landmark study. The authors used a special box that contained both an auto-injector and the IV medication. The paramedics were blinded to which treatment they were administering by having them give all patients an IM shot first, then starting an IV and giving everyone an IV bolus. All the auto-injectors and syringes looked the same, so it was impossible to tell which had active medication.

If the box contained “active” midazolam auto-injectors, then the IV bolus was a placebo and vice versa. If the box had “active” lorazepam IV bolus, then the auto-injector was a placebo. This is clever because many studies have shown that providers will go to great lengths (even tasting the two medications) to uncover which is the “active” medication. This often destroys the randomization process that is so critical to research.

Another interesting technique was the inclusion of an automatic, time-stamped voice recorder that was activated as soon as the box was opened. Most studies try to use the notoriously inaccurate times on the patient-care report or have providers fill out an extra piece of paper with study information—or sometimes they even have to be interviewed by telephone after the fact. The paramedics in this study could simply say what was happening, such as the “IM shot has been given” and “the seizure has stopped.” The recordings were later analyzed and the accurate time stamp extracted.

Note that Seattle’s Medic One program has measured improvements objectively for decades with voice recordings for cardiac arrest patients. This system provides valuable feedback, which the crews look forward to hearing to help measure improvements objectively. The technique, however, is dependent on a cumbersome ECG monitor add-on, and it unfortunately hasn’t caught on with the rest of us. It’s too bad we appear to be more afraid of recording our errors than we are motivated to learn from them, and eventually save more lives. Congratulations to RAMPART for incorporating state-of-the-art recording boxes to get accurate data. This article originally appeared in May 2012 JEMS as “Gender Matters: Study compares cardiac care for male vs. female patients.”