Several studies have made it clear that requiring two or more systemic inflammatory response syndrome criteria to define sepsis does not identify the sickest patients with a greater risk for death, one researcher noted. From Medpage Today.
This article originally appeared in MedPage Today.
Updated definitions of sepsis and septic shock unveiled here Monday eliminate criteria previously used for diagnosis that, research has shown, are nonspecific and have led to missed diagnosis as well as overdiagnosis, researchers said.
The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3), made public at an afternoon session of the Society for Critical Care Medicine (SCCM) 45th Critical Care Congress, were simultaneously published in the Journal of the American Medical Association.
The new definitions do away with the current use of two or more systemic inflammatory response syndrome (SIRS) criteria for sepsis diagnosis. Components of SIRS include tachycardia, tachypnea, hyperthermia or hypothermia, and elevated white blood count.
Led by Mervyn Singer, MD, of University College London, and Clifford Deutschman, MD, MS, of Hofstra-Northwell School of Medicine in New Hyde Park, N.Y., the international task force that developed the new definitions unanimously considered the requirement for two or more SIRS criteria to be unhelpful in the diagnosis of sepsis.
Recent studies have shown that SIRS symptoms occur in a large majority of hospitalized patients and are often associated with benign conditions.
"The SIRS criteria do not necessarily indicate a dysregulated, life-threatening response," the task force wrote. "SIRS criteria are present in many hospitalized patients, including those who never develop infection and never incur adverse outcomes."
The new definition for sepsis includes evidence for infection, plus life-threatening organ dysfunction, which is clinically characterized by an acute change of two points or greater on the Sequential [Sepsis-related] Organ Failure Assessment (SOFA) score.
Septic shock is now defined to include sepsis with fluid-unresponsive hypotension, serum lactate level greater than 2 mmol/L, and the need for vasopressors to maintain mean arterial pressure of 65 mm Hg or greater.
"These updated definitions and clinical criteria should clarify long-used descriptors and facilitate earlier recognition and more timely management of patients with sepsis or at risk of developing it," according to the task force's publication.
"Sepsis is common and it is one of the top killers in U.S. hospitals and worldwide," task force member Christopher W. Seymour, MD, of the University of Pittsburgh School of Medicine, told MedPage Today.
"It has been almost two decades since a rigorous approach has been undertaken to better define sepsis and during that time a lot of new science has emerged examining the pathophysiology of sepsis, in particular how the body responds to it."
He noted that in just the last year or so, several studies have made it clear that requiring two or more SIRS criteria to define sepsis does not identify the sickest patients with a greater risk for death.
Seymour and colleagues conducted a study to examine the validity of the revised sepsis definitions in a cohort of 148,907 suspected sepsis infections.
Their analysis identified a rapid method for identifying suspected sepsis outside the critical care hospital setting which includes two or more of the following clinical criteria: respiratory rate of 22/min or greater, altered mentation or systolic blood pressure of 100 mm Hg or less.
The bedside clinical scoring system is known as "quick SOFA" or qSOFA.
The one in four (25%) patients in their analysis with two or more positive qSOFA symptoms accounted for 70% of sepsis patients, Seymour said.
"We showed that the qSOFA model is finding the sickest patients who should go on to have the full SOFA assessment or a full battery of laboratory tests to confirm sepsis," he said.
The task force recommended that qSOFA criteria be used to prompt clinicians "to further investigate for organ dysfunction, to initiate or escalate therapy as appropriate, and to consider referral to critical care or increase the frequency of monitoring."
"The task force considered that positive qSOFA criteria should also prompt consideration of possible infection in patients not previously recognized as infected," the task force wrote.
The revised task force recommendations define septic shock as as a "subset of sepsis in which underlying circulatory, cellular and metabolic abnormalities are associated with a greater risk of mortality than sepsis alone."
"Adult patients with septic shock can be identified using the clinical criteria of hypotension requiring vasopressor therapy to maintain mean BP 65 mm Hg or greater and having a serum lactate level greater than 2 mmol/L after adequate fluid resuscitation."
In an editorial published in JAMA along with the new definitions, Edward Abraham, MD, of Wake Forest School of Medicine in Winston-Salem, N.C., cautioned that the new definitions, while helpful, do not alleviate concerns regarding the nonspecific nature of sepsis, which is still considered a syndrome and not a disease.
"Although the present definition for sepsis provides needed evolution in categorization of this syndrome, incorporation of more information about the molecular and cellular characterization of sepsis may have been helpful," he wrote.
"Hopefully, the next iteration of this consensus process will take full advantage of the rapidly advancing understanding of molecular processes that lead from infection to organ failure and death so that sepsis and septic shock will no longer need to be defined as a syndrome, but rather as a group of identifiable diseases, each characterized by specific cellular alterations and linked biomarkers."
The new definitions were endorsed by some three dozen other organizations worldwide besides the SCCM, including the American Thoracic Society, the European Respiratory Society, and the European Society of Intensive Care Medicine, as well as related organizations in Africa, Asia, South America, and the Middle East.