Cardiac & Resuscitation, Patient Care, Trauma

Research Studies Measure Prehospital Identification of Sepsis

Issue 3 and Volume 37.

EMS & Sepsis
The recent focus on prehospital identification of severe sepsis and lactate testing should remind us of the early days in ST-elevation myocardial infarction (STEMI) recognition and 12-lead ECGs. Those questioning the value of EMS and ALS argued that machines were too costly, that 12-lead interpretation—and the inevitable required transmission—was too difficult, and that the number of patients who would benefit was too small.

I’m happy that history has proven the skeptics wrong. EMS now plays a central role in STEMI care with unquestionable success. This success isn’t necessarily because we administer thrombolytics in the field but because improved assessment and recognition leads to improved care in the hospital. Early recognition of sepsis seems to be playing out the same way.

Band R, Gaieski D, Hylton J, et al. Arriving by emergency medical services improves time to treatment endpoints for patients with severe sepsis or septic shock. Acad Emerg Med. 2011;18(9):934–940.

These authors evaluated 963 severe sepsis patients who presented to a single Philadelphia emergency department (ED). Patients were split into two groups: arriving by EMS and not. Those who arrived by ambulance received antibiotics 36 minutes faster (116 minutes vs. 152 minutes) than patients who presented to the ED on their own.

They also noted that the 397 EMS patients tended to be sicker, with higher serum lactate levels and acuity. When the authors mathematically adjusted for these differences, there found no difference in mortality between the two groups despite earlier care. They discuss the possibility that unmeasured differences in severity might account for this.

This study focused only on the mode of arrival and not EMS’ role in recognition. It’s unclear how many arrived by BLS vs. ALS ambulances, but no difference was seen between municipal and private ambulance arrival, or whether the EMS crew clearly identified the patients as being a “sepsis” patient.

Studnek J, Artho M, Craymon G, et al. The impact of emergency medical services on the ED care of severe sepsis. Am J of Emerg Med. 2012;30(1):51–56.

Studnek and his group also primarily looked at sepsis patients arriving by EMS, but secondarily, they looked at the effect of a prehospital field diagnosis of sepsis. The setting is a single large EMS agency in North Carolina and single large hospital in that system.

Out of 311 patients with a diagnosis of sepsis and complete records, 51% received EMS care before arrival and received antibiotics 35 minutes sooner (111 minutes vs. 146 minutes) than those arriving by other means.

Severe sepsis criteria for adults included 1) confirmed infection, 2) pulse > 90/min; respirations > 20/min 3) temperature > 38° C or < 36° C, 4) systolic blood pressure < 90 mmHg or mean arterial pressure of < 65 mmHg after 20 mL/kg fluid bolus; 5) serum lactate greater than or equal to 4.0 mmol/L. The authors note that “measurement of temperature or point-of-care lactate could aid EMS personnel in more timely and accurate diagnosis of sepsis.”

Pryor R, Seitz J, Morley J, et al. Estimating core temperature with external devices after exertional heat stress in thermal protective clothing. Prehosp Emerg Care. 2012:16(1);136–141.

Temperature is one of the basic vital signs, and its measurement is essential to good patient care. This group from Pittsburgh designed a prospective controlled trial to check the internal core and external skin temperatures of 50 firefighters exerting themselves while wearing full protective clothing, including self-contained breathing apparatus. Core temperature (Tc) was measured with an ingestible pill with radio receiver (right out of a Bond movie). Tc was compared to temperatures measured by two different tympanic (ear), a temporal artery and an adhesive forehead thermometer.

Kudos to this group for constructing a thorough and realistic experiment on such a basic and important topic. Unfortunately, none of the external thermometers reliably correlated with the Tc. The authors’ conclusion warns us that temperature readings from these external non-invasive devices are inaccurate and could be misleading during fire-ground rehab operations. EMS providers should maintain a high index of suspicion for heat-related illness regardless of thermometer readings. Perhaps a brilliant inventor might read this and create a new more accurate device.

Watch Box
The National Association of EMS Physicians held its annual meeting in January in Tucson, Ariz. Preliminary reports from large trials were previewed. Look for the full reports on the following: Wik L, Olsen JA, Persse D, et al. Comparison of survival-to-hospital discharge between integrated AutoPulse CPR and manual CPR during out-of-hospital cardiac arrest; The Circulation Improving Resuscitation Care (CIRC) Trial. Prehosp Emerg Care. 2012:16;P152.

Many of us were curious to see the results of this CIRC trial, especially after the premature discontinuation of the Aspire trial due to preliminary negative effects of the AutoPulse. This prospective, randomized controlled trial enrolled 4,559 cardiac arrests from multiple international and U.S. sites. Survival to discharge in the AutoPulse group was 9.4% vs. 11% with high-quality manual CPR. Their conclusion: AutoPulse is statistically equivalent to manual CPR.

My conclusion: I look forward to reading the full paper and getting more details before running to make a purchase. Mathematical adjustments may equate a 1.6% difference, but that’s still roughly 35 humans (by my crude math) who might be alive today if had they received manual
CPR. This article originally appeared in March 2012 JEMS as “Time & Temperature: A recipe for good EMS care.”