Sepsis is the primary cause of death from infection. Early identification and treatment of sepsis is important in improving patient outcomes. The consensus conference sought to differentiate sepsis, which is defined as “life-threatening organ dysfunction caused by a dysregulated host response to infection” from uncomplicated infection.
Sepsis was last classified in a 2001 guideline that based its definition on the presence of two or more systemic inflammatory response syndrome (SIRS) criteria, which included an elevated temperature, heart rate higher than 90 bpm, respiratory rate higher than 20 breaths per minute, and a white blood cell count greater than greater than 12,000 mcL or less than 4,000 mcL or greater than 10% immature bands.
The problem with the SIRS definition of sepsis is that while it reflects a response to infection, it does not sufficiently distinguish between individuals with infections and those with a dysregulated response that leads to a poor prognosis, which is the definition of sepsis. The current consensus conference redefines sepsis with a more direct emphasis on organ dysfunction, as this is the aspect of sepsis that is most clearly linked to patient outcomes.
In the consensus conference document, sepsis is defined as a “life-threatening organ dysfunction caused by a dysregulated host response to infection.” The guidelines recommend using the quick version of the sequential (sepsis-related) organ failure assessment score (qSOFA) to identify patients with sepsis. In its long form, the SOFA used seven clinical and laboratory data points for completion, and is best suited to use in an intensive care setting where detailed data are available. The qSOFA score has only three criteria and by being easier to use can aid in rapid identification of sepsis and the patients most likely to deteriorate from sepsis.
The qSOFA criteria predict poor outcome in patients with infection who have two or more of the following: respiratory rate greater than or equal to 22 breaths/min, new or worsened altered mentation, or systolic blood pressure less than or equal to 100 mm Hg. Unlike the full SOFA score, the qSOFA does not require any laboratory testing and so can be performed in the office or bedside on a hospital floor. The qSOFA does not necessarily define sepsis, rather it identifies patients at a higher risk of hospital death or prolonged ICU stay. The consensus conference suggests that “qSOFA criteria be used to prompt clinicians to further investigate for organ dysfunction, initiate or escalate therapy as appropriate, and consider referral to critical care or increase the frequency of monitoring, if such actions have not already been undertaken.” The task force suggested that the qSOFA score may be a helpful adjunct to best clinical judgment for identifying patients who might benefit from a higher level of care.
Septic shock is defined as a subset of sepsis in which profound circulatory, cellular, and metabolic abnormalities are associated with a greater risk for death than sepsis alone. Septic shock can be identified when, after adequate fluid resuscitation, the patient requires vasopressor therapy to maintain mean arterial pressure of at least 65 mm Hg and has a serum lactate level greater than 2 mmol/L.
Once sepsis is suspected, prompt therapy needs to be started as per the Surviving Sepsis Campaign Guidelines. The qSOFA criteria can be used to identify patients at high risk for morbidity and mortality. Within 3 hours, a lactate level should be obtained as well as blood cultures from two separate sites drawn prior to administration of antibiotics (but do not delay antibiotic administration). Empiric broad-spectrum antibiotics should be given within 45 minutes of the identification of sepsis. Antibiotic choice will vary per clinician/institution preference, but should likely include coverage for Pseudomonas and MRSA (piperacillin/tazobactam and vancomycin, for example). Antibiotics should be reassessed daily for de-escalation. Administer 30 mL/kg crystalloid for hypotension or lactate greater than or equal to 4 mmol/L. Within 6 hours, vasopressors should be given for hypotension that does not respond to initial fluid resuscitation to maintain a mean arterial pressure (MAP) of at least 65mm Hg. In the event of persistent hypotension after initial fluid administration (MAP under 65 mm Hg) or if initial lactate was greater than or equal to 4 mmol/L, volume status and tissue perfusion should be reassessed and lactate should be rechecked if it was initially elevated.
The bottom line
A 2016 international task force recommended that the definition of sepsis should be changed to emphasize organ dysfunction rather than a systemic inflammatory response. Use of the qSOFA score, which relies only on clinically observable data rather than laboratory evaluation, is recommended to identify patients at high risk for morbidity and mortality. Early recognition of sepsis and evaluation with qSOFT should facilitate early treatment and improve survival.
References
Singer M, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) FRCP; JAMA. 2016;315[8]:801-10. doi: 10.1001/jama.2016.0287.
Levy MM, Fink MP, Marshall JC, Abraham E, Angus D, Cook D, et al. 2001 SCCM/ESICM/ACCP/ATS/SIS International Sepsis Definitions Conference. Crit Care Med. 2003 Apr;31(4):1250-6.
Singer M, Deutschman CS, Seymour C, et al. The third international consensus definitions for sepsis and septic shock (sepsis-3). JAMA. 2016 Feb 23;315(8):801-10.
Dellinger RP, Carlet JM, Masur H, Gerlach H, Calandra T, Cohen J, et al. Surviving Sepsis Campaign guidelines for management of severe sepsis and septic shock. Crit Care Med. 2004 Mar;32(3):858-73.
Dr. Mills is assistant residency program director and assistant professor in the department of family and community medicine and department of physiology at Sidney Kimmel Medical College at Thomas Jefferson University. Dr. Botti is a second-year resident in the family medicine residency program department of family and community medicine at Sidney Kimmel Medical College at Thomas Jefferson University. Dr. Skolnik is associate director of the family medicine residency program at Abington (Pa.) Memorial Hospital and professor of family and community medicine at Temple University, Philadelphia.
