Last month, new definitions for sepsis and septic shock (Sepsis-3) were released and published in the Journal of the American Medical Association (JAMA). The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)
is the work of a consensus panel of experts from the Society of Critical Care Medicine and the European Society of Intensive Care Medicine. There have been multiple revisions and evolutions to the definitions of sepsis and treatment strategies over the years as we continue to increase our understanding of the complex biology of sepsis and the physiologic effects of sepsis on the body. We are constantly adapting this knowledge to clinical practice. Despite advances in our understanding of sepsis biology, it remains a condition associated with high morbidity and mortality worldwide. Despite constant advances in pharmacologic treatments and organ support devices (i.e. mechanical ventilation, renal replacement therapies, etc.) early identification and treatment of patients with sepsis remains the cornerstone of improving survival. The new definitions simplify the classification of sepsis and provide tools to identify those with suspected infection that are at risk of developing complications of sepsis by utilizing the Sequential (sepsis-related) Organ Failure Assessment (SOFA)
and qSOFA scores.
The new definitions and risk assessment scores take the focus off inflammation and place it on the organ dysfunction related to the dysregulated host response that is sepsis. In fact, Sepsis-3 defines sepsis as “Life-threatening organ dysfunction caused by a dysregulated host response to infection (Singer et al. 2016).” A lay term definition is also provided in the article describing sepsis as “a life-threatening condition that arises when the body’s response to infection injures its own tissues and organs” (Singer et al. 2016). This provides helpful terminology in speaking with families about the complex and complicated condition.
Why the change?
Prior to the release of Sepsis-3, healthcare providers generally referred to four different levels of sepsis: systemic inflammatory response syndrome (SIRS), sepsis
(SIRS in response to a confirmed infectious process), severe sepsis
(sepsis plus organ dysfunction as evidenced by hypotension or hypoperfusion to one or more organs), and septic shock
(sepsis with persisting arterial hypotension or hypoperfusion despite adequate fluid resuscitation).
Over the years, there has been much controversy over the SIRS criteria, as they are considered to have poor specificity and sensitivity for predicting the development of sepsis. The SIRS criteria – fever, tachycardia, tachypnea, leukopenia/leukocytosis – are present in many conditions, both in chronic medical illness and in acute reactions to infection. A patient with acute bacterial pharyngitis with dehydration from poor intake and tachycardia from dehydration and fever can be treated outpatient and is at very low risk of progressing to septic shock despite meeting SIRS criteria. Furthermore, the “levels” of sepsis infers there is a continuum or spectrum that a patient with sepsis follows in the course of illness and this is not the case.
In a nutshell, the focus of the new definitions as described above is defining sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. The Sequential (sepsis-related) Organ Failure Assessment (SOFA)
is presented as a tool to identify organ dysfunction and the risk of a patient with infection in developing sepsis. SIRS has been eliminated from sepsis vocabulary, as has severe sepsis, which was considered redundant. So now we have:
- Sepsis: life-threatening organ dysfunction caused by a dysregulated host response to infection. Organ dysfunction is measured by changes in the Sequential (sepsis-related) Organ Failure Assessment (SOFA) score of two points or more. In a patient with unknown baseline, the beginning score is zero.
- Septic shock: a subset of sepsis with vasopressor requirement to maintain MAP >65 and serum lactate > 2 mmol/L in the absence of hypovolemia (i.e. after a patient has received adequate fluid resuscitation).
The SOFA Score (Vincent et. al 1996) provides clinical measures to identify organ dysfunction; these criteria identify infected patients most likely to develop sepsis. Organ dysfunction is identified as an acute change in SOFA score of greater than or equal to two. These clinical variables include PaO2/FiO2 ratio, platelet count, bilirubin, MAP with and without the presence of vasoactive agents, Glascow Coma Scale, creatinine and urine output.
(Quick SOFA) Criteria is an additional tool highlighted in Sepsis-3. The clinical variables of the qSOFA are:
- Respiratory rate > 22
- Altered mentation (GCS < 15)
- Systolic blood pressure ≤ 100
The presence of any two of these criteria (qSOFA) in a patient with a known infection should prompt further evaluation for organ dysfunction. This tool can be utilized by the bedside nurse.
Nursing implications of Sepsis-3
While these definitions will not change how we treat patients with sepsis or presumed sepsis, they do provide more straightforward terminology, as well as a bedside tool to evaluate a patient with infection, potentially allowing us to both identify at-risk patients sooner and treat earlier. The presence of the qSOFA criteria in a patient with infection should prompt further evaluation of the patient and possible measurement of the more detailed SOFA criteria to evaluate for organ dysfunction. As a nurse, awareness and understanding of the most up-to-date terminology surrounding sepsis improves care of our patients and allows for better communication of patient information to colleagues in a consistent manner. Nurses are in a key position at the bedside to monitor and identify patient in the early stages of clinical decline and have the potential to positively impact patient outcomes by facilitating early interventions and treatment of the septic patient.
With this information, we can improve our communication. In the past, we might have said, “I am very concerned about Mr. X. He was admitted to the floor for treatment of a urinary tract infection. I just have a feeling this patient is declining; he looks like he might be septic.” Now, with our new definitions, we can say, “I am very concerned about Mr. X. He was admitted to the floor for treatment of a urinary tract infection. Since admission, he has deteriorated clinically; his qSOFA score is two, he has a respiratory rate of 30 and his systolic blood pressure is 80. When he arrived in the ED, his SOFA score was one due to a creatinine of 1.5. Now his urine output is down to 15 mL/hr, and his MAP is 60. I think we need to order more labs and have someone come re-evaluate the patient for possible transfer to the ICU.” As nurses, we often know when something is changing and our patient’s clinical condition is headed in the wrong direction. Familiarization with these tools provides us with more objective data to present and support our concerns.
It has now been several weeks since the release of Sepsis-3. In reviewing medical commentary, there are varying supports and criticisms of both the new definitions and on the utility of the SOFA and qSOFA scores. True, qSOFA and SOFA are not diagnostic of sepsis or septic shock, the SOFA is a predictor of mortality; but they provide objective data points that can be easily measured in the hospital setting. What remains unchanged is our goal of early identification and early treatment to reduce overall morbidity and mortality related to sepsis. Sepsis is a complex condition; in addition to overt symptomatology, there is complex biochemical, genetic and endogenous factors involved in the pathobiology of sepsis. Some pathways are well understood while others are only on the brink of being understood.
I am personally happy with the new definitions and the simplicity of the diagnostic terms of sepsis vs. septic shock. I am looking forward to the improved dialogue and communication using the SOFA criteria. As with any changes in medicine, there is typically a lag time from publication to implementation. At my hospital, in particular in the ICU, there has certainly been a lot of buzz and support for the new terminology. I would love to hear how other hospitals and facilities have reacted to Sepsis-3!
Megan Doble, MSN, RN, CRNP
Singer M, Deutschman CS, Seymour C, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-810. doi:10.1001/jama.2016.0287.
Vincent JL, Moreno R, Takala J, et al; Working Group on Sepsis-Related Problems of the European Society of Intensive Care Medicine. The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. Intensive Care Med. 1996;22(7):707-710.