Episode 119: Is a Restrictive Fluid Strategy Better for Septic Patients?
Article: Corl KA, et al. The restrictive IV fluid trial in severe sepsis and septic shock (RIFTS): A randomized pilot study. Crit Care Med. 2019; epub ahead of print.
Background
Research indicates that administering IVF to increase stroke volume and organ perfusion concurrently damages vascular integrity leading to organ edema and dysfunction
Observational studies have associated high volume IVF resuscitation with increased mortality
Optimum IVF resuscitation strategy in sepsis uncertain
Study Objective
Assess the feasibility and initial efficacy of a restrictive resuscitation strategy that significantly limits the amount of IVF administered to septic patients over the first 72 hours of ED and ICU care
Study
Randomized trial conducted in EDs and ICUs of 2 US hospitals (Brown and B&W)
Patients
Included
Adult patients > 18 years of age
Admitted from the ED to the ICU
Suspected by the treating physician of having severe sepsis or septic shock by Sepsis 2.0
Allowed patients with < 2 SIRS criteria to be enrolled if the treating attending believed sepsis to be their primary cause of illness
Have refractory hypotension (MAP < 65 mm Hg) or lactate >= 4 mmol/L after 1 L of IVF
Interventions
First 72 hours of treatment
Restrictive IVF Group
Permitted to receive up to 60 ml/kg
Usual Care Group
Received resuscitative IVF without any pre-specified or suggested limits
Resuscitative Fluids included all IVF boluses (NS and LR) and maintenance IVF
Target MAP was 65 mm Hg with IVFs and vasopressors
Type and timing of vasopressors not restricted
IVFs with meds termed non-resuscitative IVFs and not restricted. Albumin, TPN, and blood products also considered non-resuscitative IVFs
Primary outcome: 30-day all-cause mortality
Results
109 formed final study cohort; 55 in restrictive group and 54 in usual care group
IVF Resuscitation
Restrictive group: 47.1 ml/kg
Usual care group: 61.1 ml/kg
Difference of 14.0 ml/kg; 823 m
Primary outcome
Restrictive group: 21.8%
Usual care group: 22.2%
Adjusting for baseline imbalances in CKD and amount of nonresuscitative IVFs yielded no difference in observed 30-day mortality
Secondary outcomes
No difference in 60-day mortality, ICU or hospital LOS, rates of new organ failure, or changes in electrolytes
Did not observe a significant difference between groups in the number of ventilator free days among the 32 participants with respiratory failure, the restrictive group spent 22 fewer hours ventilated that usual group
Limitations
Sample sizes of pilot trials makes it underpowered to detect superiority or noninferiority in mortality
Patients and providers not blinded to the intervention
Relatively small difference in IVF between study arms may not reach clinical significance (823 ml)
Did not incorporate a formalized measurement of volume status or fluid responsiveness
Selection bias by excluding those who received more than 60 ml/kg - less sick study cohort
Take Home Point
A restrictive fluid strategy in patients with severe sepsis or septic shock did not appear to increase mortality, organ dysfunction, or adverse events
