Splanchnic Perfusion Monitoring in Septic Shock Using Doppler Ultrasound

Splanchnic Perfusion Monitoring Using Doppler Ultrasound in Septic Shock Patients: Correlation With Lactate Clearance, Organ Dysfunction, and Enteral Feeding Intolerance

evaluation whether splanchnic Doppler ultrasound indices (SMA resistive index, portal vein pulsatility fraction, hepatic artery resistive index/flow parameters) can:

1. Reflect regional tissue perfusion in septic shock, as correlated with lactate clearance.
2. Associate with organ dysfunction severity and progression (SOFA dynamics).
3. Predict enteral feeding intolerance in ICU patients receiving enteral nutrition

Sepsis is a life-threatening condition caused by a dysregulated host response to infection, leading to severe organ dysfunction. Globally, sepsis accounts for approximately 48.9 million cases and 11 million deaths annually.

A central clinical challenge is hemodynamic incoherence, where systemic targets (e.g., mean arterial pressure [MAP]) may improve while regional tissue perfusion remains impaired. Conventional systemic markers, including blood lactate clearance and central venous oxygen saturation, reflect global metabolic status and may lag behind microvascular dysfunction within specific organ beds.

The hepatosplanchnic circulation is particularly vulnerable during septic shock and may contribute to progression toward multiple organ failure through a sustained inflammatory cascade. The splanchnic region has been described as the "motor" of multiple organ failure and the "canary" of the body.

Bedside Doppler ultrasound has emerged as a noninvasive tool to assess regional perfusion. Doppler-derived indices such as the resistive index (and related parameters including portal pulsatility fraction) may detect early hemodynamic impairment at the organ-bed level before systemic biomarkers change.

Accordingly, improved bedside perfusion monitoring especially for the splanchnic circulation-may help optimize resuscitation strategy and nutritional management, and may clarify relationships between regional perfusion, organ dysfunction, and enteral feeding tolerance.

Inclusion Criteria:

• 1. Adult patients (≥18 years). 2. ICU admission with septic shock (Sepsis-3 definitions).

Exclusion Criteria:

- 1. Advanced chronic liver disease. 2. Portal vein thrombosis. 3. Mesenteric ischemia (or clinical suspicion strongly suggesting it). 4. Severe right-sided heart failure. 5. Pregnancy. 6. Morbid obesity or any condition causing poor/unsafe ultrasound acoustic window.

7. Intra-abdominal conditions preventing adequate Doppler assessment. 8. Limitation of care / do-not-resuscitate orders. 9. Pre-existing major gastrointestinal bleeding/obstruction if that is relevant to enteral feeding intolerance outcomes in your ICU.