Sepsis 101—diagnosis and treatment

In this video, from our Infectious Disease Essentials course, Dr John Fisher explains how to diagnose and treat sepsis, where sepsis can originate, and how to make sense of it all. You will also learn about the quick Sequential Organ Failure Assessment (qSOFA) score and why it's a critical tool in the management of your patients.

Manage common infections with confidence in this course. You’ll cover viral, bacterial, fungal, and parasitic disease processes, plus learn a systematic approach to differentiating between and treating various life-threatening infections, as well as less serious cases. Learn to determine whether urgent empirical therapy is needed or if it is safe to pursue an exact diagnosis before treating.

[00:00:00] Sepsis can best be defined as a systemic deleterious host response to infection which when severe can lead to acute organ dysfunction or septic shock which is not easily reversed with fluid resuscitation. Septic shock carries a mortality of 40% to 70%. Many cases of sepsis are associated with bacteremia but a focus of infection outside

[00:00:30] the bloodstream can cause the entire process. Sepsis originates from pulmonary infections and about half of the cases with 20% of patients having bacteremia from an unspecified source. Most of the rest come from the genitourinary tract or gastrointestinal tract. It can be caused by either Gram-positive or Gram-negative bacterial infections although the latter are slightly more common. The presence

[00:01:00] of Gram-positive or negative organisms stimulates an immune system cascade which leads to the production of both pro and anti-inflammatory cytokines. When an over-response occurs in this process, sepsis develops. Some patients with sepsis are obviously acutely ill upon presentation with confusion, high fever and chills, and hypotension resulting from widespread vasodilation. Babies

[00:01:30] exhibit fever or hypothermia, respiratory distress or problems of gastrointestinal function such as poor feeding, weak suck, vomiting, abdominal distension or worsening jaundice. Elderly patients often have vomiting, diarrhea, general weakness, and oliguria. When late manifestations occur, sepsis is usually obvious. Very ill patients are often unconscious,

[00:02:00] show very low blood pressure, rash, and other skin lesions or gangrenous changes in the extremities because of widespread peripheral hypoperfusion. The cytokine storm also frequently leads to the acute respiratory distress syndrome. At other times, the physician must maintain a high index of suspicion for sepsis in patients who present to emergency facilities or in hospitalized patients who develop some of the following unexplained signs

[00:02:30] or symptoms: hypothermia, tachycardia, tachypnea or hyperpnea, abdominal pain, pelvic pain, vaginal discharge, abnormal blood clotting, and altered mental status. The quick sequential organ failure score or qSOFA was developed to prompt physicians to look for organ dysfunction, initiate early antibiotic treatment that is within one hour, and refer the patient to an ICU.

[00:03:00] Thus, altered mentation with a Glasgow Coma score below 14, systolic blood pressure below 100, and a respiratory rate of over 21 are the three parameters to quickly assess. A score of greater than or equal to 2 is highly suggestive of organ dysfunction and a poor outcome of sepsis. Sepsis is most common and most dangerous in pregnant women,

[00:03:30] older adults, and children under one year old, people with chronic health conditions like diabetes, kidney or lung disease or cancer, and immunocompromised individuals. So it is important to quickly and efficiently diagnose sepsis, especially in these patient populations so the treatment can be initiated immediately. The management of sepsis can be complicated. Emergently, the patient's oxygenation, and organ perfusion needs treatment.

[00:04:00] Oxygenation is satisfactory if the central venous O2 saturation is above 75%. Fluid resuscitation is necessary to maintain a CVP of 8 to 13 mmHg and a mean arterial pressure of at least 65 mmHg of mercury. If fluids fail to reach these targets, norepinephrine is the pressor of choice. Antimicrobial failure is likely in the presence of a large abscess.

[00:04:30] Thus, the abscess has to be located and adequately drained. When adequate history and physical signs are available, identifying the offending organ system is crucial to the selection of antimicrobial agents. When no history is available and there are no physical signs suggesting the offending organ system, several blood cultures should be obtained and very broad antimicrobial coverage, for example, with a carbapenem should be given.

[00:05:00] In many instances, microscopy and recent culture results will direct appropriate antibiotic choices but if not, empirical therapy is necessary. Empirical choices should be based on the suspected source of infection. For pneumonia, a fluoroquinolone or azithromycin plus an antipseudomonal beta-lactam like piperacillin-tazobactam or cefepime should be given. If the causes an intraabdominal infection,

[00:05:30] piperacillin-tazobactam or a carbapenem are excellent choices for mixed aerobic and anaerobic infections. For patients with a beta-lactam allergy, a fluoroquinolone plus metronidazole is a good alternative. For urosepsis, a fluoroquinolone is a good choice. And for sepsis of unknown cause, vancomycin plus a carbapenem like meropenem is warranted.