Septic Shock: Moving in the Right Direction
By: Steven Q. Simpson, MD, FCCP, FACP
February 8, 2017
Septic shock accounts for much of sepsis’ morbidity and mortality. With reports of rising incidence and declining mortality rates in septic shock, this month’s issue of the journal CHEST includes an examination of septic shock incidence and mortality trends over 10 years at 27 US academic medical centers (AMCs) using electronic health record (EHR) clinical data vs claims data.
Researchers examined hospitalizations of all adults from January 2005 through December 2014 with either the septic shock ICD-9 code or clinical criteria (≥ 2 consecutive days of vasopressors, blood culture orders, and 4 or more days of antibiotics). This clinical definition provided a more objective measure than medical claims data for identifying patients who receive treatment for septic shock. The study concluded that these clinical criteria indicate that septic shock incidence is rising and mortality decreasing, but less dramatically than demonstrated by ICD-9 codes.
Incidence Is Increasing
There are a lot of things packed into this CHEST article. First, it’s clear that the incidence of septic shock is increasing. This is not surprising given that two separate epidemiological investigations demonstrated in the early 2000s that the incidence of sepsis, per se, was rising at a compounding rate of approximately 8.5% per year. With the incidence of overall sepsis increasing at that rate, it is expected that the incidence of septic shock would also rise unless we intervene earlier to prevent clinical deterioration.
Mortality Is Decreasing
The second important fact revealed by the study is that the mortality rate from septic shock is decreasing. The authors sought to determine whether administrative claims based on ICD-9 codes for septic shock were inflating numbers of septic shock patients by adding patients who are less ill and have better outcomes via a “Will Rogers” effect. Since coding and administrative claims are dependent on physician documentation and its interpretation, diagnoses can be subjective. However, the more objective measure of whether or not vasopressors were used suggests that we actually are improving our treatment over time.
The current paper can’t tell us anything about why we are doing better with septic shock. However, it’s likely that we are taking a more structured approach to the care of the septic shock patient. The truly seminal and key principle of early goal-directed therapy (EGDT) is that our approach to septic shock patients should be structured, orderly, and follow logical resuscitation principles is definitely intact, and more institutions are adopting that approach over time. The Surviving Sepsis Campaign has disseminated that key principle. The campaign’s own data demonstrate that adherence to the principle results in substantive improvements in survival. It is clear that the hospitals with the best outcomes for severe sepsis and septic shock have achieved those outcomes via standardizing their approach to diagnosis and treatment.
Continue The Momentum
This sampling of academic centers represents only about 1% of the hospitals in the United States. However, the nationwide data from hospitals of all sizes and locations that prompted the investigation mirror the information that these authors found in their administrative data and that were, in fact, the impetus for this study. Quantitatively, the national numbers likely overestimate the incidence of septic shock, but qualitatively, they demonstrate that the incidence is increasing and the mortality declining in all hospitals, as the more objective data from this study demonstrate in the academic centers. It should remain reasonable for the average, nonresearch hospital to follow their administrative data as an indicator of their progress in caring for patients with severe sepsis and septic shock because the trends, at least, should be trustworthy.
These data support that there is no patient-centered need for new diagnostic criteria to diagnose severe sepsis or septic shock. We are gradually, but steadily making reductions in the lethality of these conditions, which should be our principal concern. The proposed changes by the Sepsis-3 consensus conference are interesting, but they were chosen to have higher predictive validity for mortality or prolonged ICU stay, and they have not been shown to be of benefit to patients. The most important thing we can do for our patients is to continue to make headway with recognizing sepsis early to prevent septic shock, when possible, and to pursue aggressive, data-driven approaches to septic shock when we cannot prevent it. This paper reinforces that we have been moving in the right direction. Our emphasis should be on continuing the momentum.
Steven Q. Simpson, MD, FCCP, FACP is a sepsis expert and researcher, a CHEST member, and a Professor of Medicine and Interim Director of the Division of Pulmonary and Critical Care Medicine at the University of Kansas.