Does the degree of sepsis determine the incidence and severity of acute kidney injury?
In contrast to acute kidney injury, sepsis syndrome has benefited from the development of a consensus-driven standardized definition for more than 20 years.
This definition was modified to reflect advances in the pathobiology, management, and epidemiology of sepsis. In this new schema, sepsis is defined as “life-threatening organ dysfunction caused by a dysregulated host response to infection.”
Organ dysfunction is best identified as an acute change in the total Sequential Organ Failure Assessment score ≥2 points, which reflects an overall mortality risk of approximately 10%.
Septic shock is the most severe form of sepsis with profound cellular, metabolic, and hemodynamic abnormalities that include hypotension (requiring vasopressors), as well as elevated serum lactate levels. Septic shock is associated with mortality rates over 40%.
While there are no studies assessing the incidence of acute kidney injury utilizing the new definition of sepsis, prior studies have shown that there is a stepwise increase in the severity of acute kidney injury in patients who are stratified by the severity of sepsis.
For instance, in one study, the incidence and severity of acute kidney injury, defined by the AKIN criteria, increased markedly when stratified by sepsis severity.
Furthermore, as patients progress from sepsis to severe sepsis to septic shock, the incidence of acute kidney injury that requires dialysis also increased.
Incidence of Acute Kidney Injury That Requires Dialysis
INCIDENCE OF AKI
|AKI REQUIRING DIALYSIS|
AKI , Acute kidney injury.
• Sepsis : criteria for systemic inflammatory response syndrome (SIRS) with suspected or present source of infection. SIRS criteria:
• Temperature >38°C or <36°C
• Heart rate >90/min
• Respiratory rate >20/min or PaCO 2 < 32 mm Hg
• White blood cell count >12,000/mm 3 , <4000/mm 3 or >10% bands
• Severe Sepsis : sepsis plus organ dysfunction, hypotension, or hypoperfusion as defined by:
• Lactic acidosis
• Systolic blood pressure <90
• Systolic blood pressure drop ≥40 mm Hg of normal
• Septic Shock : severe sepsis with hypotension despite adequate fluid resuscitation