Implementation of an EMS protocol to improve prehospital sepsis recognition.

PURPOSE: Optimal sepsis outcomes are achieved when sepsis is recognized early. Recognizing sepsis in the prehospital, EMS setting can be challenging and unreliable. The purpose of this study is to evaluate whether implementation of an EMS sepsis screening and prehospital alert protocol called PRESS (PREhospital SepsiS) is associated with improved sepsis recognition by EMS providers. DESIGN: We conducted a 12-month, before-after implementation study of the PRESS protocol in a large, public EMS system. The study intervention was a PRESS training program delivered to EMS providers. EMS patient inclusion criteria included: age ≥ 18 years, EMS systolic blood pressure < 110 mmHg, EMS heart rate > 90 bpm, and EMS respiratory rate > 20 bpm. Study exclusion criteria included the presence of any of following EMS conditions: trauma, cardiac arrest, pregnancy, toxic ingestion, or psychiatric emergency. Retrospective chart review was performed on all eligible EMS encounters during the study period. The primary outcome variable was the proportion of patients with sepsis who were identified by EMS providers. RESULTS: Approximately 300 EMS providers were trained to use PRESS. A total of 498 patient encounters met criteria for study inclusion; 222 were excluded, primarily due to trauma. A total of 276 patient encounters were analyzed. Sepsis recognition by EMS providers increased from 12% pre-PRESS protocol to 59% post-PRESS protocol (p < 0.001). In a post-hoc analysis of the post-PRESS cohort, septic patients who were identified by EMS received antibiotics 24 min faster than septic patients who were not identified by EMS [28 min (IQR 18-48) vs 52 (IQR 27-98), respectively, p = 0.021]. CONCLUSION: Implementation of an EMS sepsis screening and prehospital alert protocol was associated with an increase in sepsis recognition rates by EMS providers and a decrease in time to first antibiotic administration in the emergency department. Further studies are needed to evaluate the impact of this protocol in other populations.

A fluorescent screening assay for identifying modulators of GIRK channels.

G protein-gated inward rectifier K+ (GIRK) channels function as cellular mediators of a wide range of hormones and neurotransmitters and are expressed in the brain, heart, skeletal muscle and endocrine tissue(1,2). GIRK channels become activated following the binding of ligands (neurotransmitters, hormones, drugs, etc.) to their plasma membrane-bound, G protein-coupled receptors (GPCRs). This binding causes the stimulation of G proteins (Gi and Go) which subsequently bind to and activate the GIRK channel. Once opened the GIRK channel allows the movement of K+ out of the cell causing the resting membrane potential to become more negative. As a consequence, GIRK channel activation in neurons decreases spontaneous action potential formation and inhibits the release of excitatory neurotransmitters. In the heart, activation of the GIRK channel inhibits pacemaker activity thereby slowing the heart rate. GIRK channels represent novel targets for the development of new therapeutic agents for the treatment neuropathic pain, drug addiction, cardiac arrhythmias and other disorders(3). However, the pharmacology of these channels remains largely unexplored. Although a number of drugs including anti-arrhythmic agents, antipsychotic drugs and antidepressants block the GIRK channel, this inhibition is not selective and occurs at relatively high drug concentrations(3). Here, we describe a real-time screening assay for identifying new modulators of GIRK channels. In this assay, neuronal AtT20 cells, expressing GIRK channels, are loaded with membrane potential-sensitive fluorescent dyes such as bis-(1,3-dibutylbarbituric acid) trimethine oxonol [DiBAC4(3)] or HLB 021-152 (Figure 1). The dye molecules become strongly fluorescent following uptake into the cells (Figure 1). Treatment of the cells with GPCR ligands stimulates the GIRK channels to open. The resulting K+ efflux out of the cell causes the membrane potential to become more negative and the fluorescent signal to decrease (Figure 1). Thus, drugs that modulate K+ efflux through the GIRK channel can be assayed using a fluorescent plate reader. Unlike other ion channel screening assays, such atomic absorption spectrometry(4) or radiotracer analysis(5), the GIRK channel fluorescent assay provides a fast, real-time and inexpensive screening procedure.