Small-volume hypertonic saline/pentastarch improves ileal mucosal microcirculation in experimental peritonitis

Area of Science:

• Critical Care Medicine
• Sepsis Pathophysiology
• Microcirculation Research

Background:

• Septic shock significantly impairs microcirculatory blood flow, particularly in the ileum.
• Early resuscitation is crucial for managing septic shock and preventing organ dysfunction.
• The efficacy of different fluid resuscitation strategies on microcirculation in early sepsis remains under investigation.

Purpose of the Study:

• To compare the effects of hypertonic saline/hydroxyethyl starch (HSS-HES) and isotonic saline/hydroxyethyl starch (ISS-HES) on ileal microcirculatory blood flow (MBF) in early septic shock.
• To evaluate the impact of these fluids on systemic hemodynamics and metabolism.
• To determine if HSS-HES can improve ileal microcirculation despite low mean arterial pressure (MAP).

Main Methods:

• A porcine model of fecal peritonitis-induced septic shock was utilized.
• Ileal mucosal and muscularis MBF were continuously measured using laser Doppler flowmetry (LDF).
• Animals were randomized to receive either HSS-HES or ISS-HES (10 mL/kg over 10 min) post-septic shock induction.

Main Results:

• Septic shock led to reduced MAP, cardiac index (CI), and significant decreases in ileal mucosal and muscularis MBF.
• HSS-HES administration significantly increased ileal mucosal MBF (+192%) compared to baseline, whereas ISS-HES did not.
• Muscularis MBF did not change significantly in either group; HSS-HES group showed higher osmolarity and sodium levels.

Conclusions:

• Small-volume resuscitation with HSS-HES, but not ISS-HES, effectively improved ileal microcirculatory impairment in a peritonitis-induced septic shock model.
• This microcirculatory improvement occurred even with low MAP, suggesting a potential benefit for early severe sepsis management.
• HSS-HES may be a valuable therapeutic option for addressing microcirculatory dysfunction in the initial phase of sepsis.