Monday Morning Medical Director’s Message
Sepsis and its most severe consequence, septic shock, are time-sensitive, life-threatening illnesses. In previous weeks, we discussed how an astute EMS provider armed with the basic skills of history-taking, physical examination, use of ancillary testing, and differential diagnosis is quite capable of diagnosing sepsis in the field. Early diagnosis and early intervention improve survivability.
What are the pathophysiological events that are responsible for the vital sign abnormalities, organ damage, and clinical deterioration that invariably occur in the patient whose septic condition is undetected or untreated? The usual culprit is an infectious agent, most often bacterial, although viruses and other pathogens could be involved. Bacterial invasion, with release of endotoxins or exotoxins, triggers a vigorous response from the body’s immune/inflammatory systems. The body’s cellular defense system is stimulated, causing activation of monocytes and neutrophils (white blood cells), as well as tissue macrophages, which engulf and digest bacteria and recruit T lymphocytes to assist in fighting the bacterial invasion. | 
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In addition to these cells that respond to the invasion, several chemicals are released during the immune/ inflammatory reaction, which include cytokines, proteases, kinins, and reactive oxygen species. Although the purpose of the immune/inflammatory reactions is to contain, suppress, destroy, and remove the invading organisms, often in sepsis these reactions are exaggerated and counterproductive, leading to coagulation, vascular dilation, and vascular injury. These events can lead to a vicious cycle resulting in organ damage, hypotension, and all the clinical signs that healthcare providers battle as they struggle to keep patients alive.
Early and aggressive intervention is required to provide the septic patient with a favorable chance of survival, which begins in the field. EMS providers are well-equipped with the capacity to make a reasonable diagnosis of sepsis and impending septic shock. Basic tenets of intervention include IV or IO insertion, oxygen, cardiac, and capnography monitoring. Our EMS protocols call for a crystalloid fluid bolus (normal saline) of 20 cc per kg. The fluid boluses can be provided in increments (250 or 500 mL) and repeated. Vital signs should be repeated every 5 minutes. Paramedics should document the clinical response to each fluid bolus.
Septic shock, the most severe complication of sepsis, carries a high mortality rate. By definition, septic shock is present when a patient remains hypotensive despite an adequate fluid bolus, thereby requiring the use of vasopressors to maintain adequate perfusion. The patient will have elevated lactate levels of 4 or higher, and signs of end-organ impairment will be present. Vasopressors in the field include push dose epinephrine as in our UH protocols, or dopamine. Epinephrine, the most versatile drug in our armamentarium, is not only a vasopressor causing vasoconstriction via vascular alpha-1 activation, but it is also an inotropic agent that increases cardiac contractility, or force of heart contraction. Furthermore, epinephrine is also a positive chronotropic agent, increasing the heart rate. These direct cardiac stimulatory effects occur via activation of beta-1 receptors in the heart. These three epinephrine-related compensatory responses are necessary to combat the vasodilation, cardiac suppression, and hypotension that occur in septic shock.
Most authorities agree that early antibiotic administration improves survivability based on evidence. The goal for antibiotic administration is within one hour of recognition of sepsis. To this end, some EMS agencies across the country have protocols for antibiotic administration in the field for septic patients. EMS providers were trained to draw blood cultures. A 2020 study in the HCA Healthcare Journal of Medicine showed evidence that prehospital antibiotics improved morbidity and mortality of EMS-transported patients with sepsis. The length of ICU stay was reduced, as well as days on the ventilator.
Thank you,
Andrew Garlisi, MD
EMS Medical Director
University Hospitals EMS Training & Disaster Preparedness Institute