The recommendation for a 30 mL/kg crystalloid fluid bolus in a septic patient was established by the Surviving Sepsis Campaign (SSC), with the current guidelines published in 2018 still recommending the bolus regimen (strong recommendation, low quality of evidence). Since its publication, reviews and commentaries from real world settings note the minimal supporting clinical data and reliance on expert opinion for this recommendation. These reviews suggest that the 30 mL/kg fluid challenge can needlessly expose patients to large volumes of fluid, and could actually be harmful by overloading organ function and paradoxically worsening shock. Other guidelines like American College of Emergency Physicians (ACEP) recommend individualizing fluid resuscitation needs for each patient. [1], [2], [3]
A 2020 review discussing the lack of supporting evidence for fluid resuscitation in septic shock recommends a flat initial bolus of 500 mL of balanced crystalloid solutions, followed by monitoring of patient’s response and contemplation of further bolus doses. This recommendation is based on the initial findings from a 1832 publication that pioneered the concept of fluid resuscitation that administered a fluid “ounce after ounce” while closely observing the patient. In other words, the recommendation lacks clinical evidence, but the authors consider it a safer approach to resuscitation of critically ill patients. [2], [3], [4]
A 2014 article reviews the evidence around fluid administration in patients with septic shock by comparing goal-directed fluid therapy (GDT) approaches to usual care or historical controls. The GDT approaches aimed to achieve specific fluid administration targets within a defined time period, often targeting a central venous pressure (CVP) of 8-12 mmHg. The four randomized controlled trials that were assessed comparing GDT to usual care did not find a significant reduction in mortality with GDT. However, these trials were inconsistent and heterogeneous. When the largest trial (ProCESS) was removed, the remaining three trials showed a significant reduction in mortality with GDT. Notably, the ProCESS trial found that patients receiving usual care received significantly less IV fluid at 6 hours and had numerically lower mortality compared to the GDT group. [5]
Eighteen observational studies were also analyzed. While bundled GDT was associated with a significant increase in survival overall, the difference in IV fluid volumes administered between treatment groups showed significant heterogeneity across studies. Most studies reported greater IV fluid volumes in the GDT groups, but the differences were inconsistent. There are also several limitations noted across the randomized and observational studies. In particular, multiple interventions were compared between groups, not just fluid administration, making it difficult to attribute outcomes to any single component. The inconsistent results regarding IV fluid volumes administered further complicate determining the optimal fluid resuscitation approach. These findings suggest there are potential risks of excessive IV fluid administration in septic shock patients. However, the evidence does not firmly provide quantitative fluid administration targets and there was no direct evidence for rounding down fluid boluses to the nearest 500 mL or 100 mL amount. [5]
In a 2021 retrospective chart review, medical records of emergency general surgery (EGS) patients who were undergoing surgery for abdominal sepsis within 24 h of admission were analyzed for incidence of mortality. A total of 301 patients (55% male, mean age 55 years) were included over 8 years, of which 257 (85%) patients survived to discharge. Though fluid restrictions were not assessed within the study, investigators observed an increasing mortality rate per increment with increasing preoperative resuscitation fluid per kg (<10 to <70 mL/kg; 8.8% vs 31.6%; p= 0.004). Lower mortality rates were observed in patients who received <30 mL/kg (11.3%) versus patients who received >30 mL/kg (21%; p= 0.02). However, once analysis was corrected for age and physiologic factors, there were no significant differences in mortality between groups. [6]