Efficacy of Liberal Versus Restricted IV Fluid Approach in the Management of Sickle Cell Vaso-Occlusive Crisis (FLASC)

Imam Abdulrahman Bin Faisal University

Status: Not yet enrolling

Conditions: Vaso Occlussive Crisis; SCD

Treatments: Drug: Sodium Chloride (NaCl) 0.9 %

Study type: Interventional

Funder types: Other

Identifiers

NCT07188766

2025-01-0451

Details and patient eligibility

About

Sickle cell disease (SCD) is a prevalent inherited blood disorder characterized by vaso-occlusive crises (VOCs), which lead to severe pain and complications. Despite hydration being a cornerstone of VOC management, the optimal fluid strategy remains uncertain. This study evaluates restrictive versus liberal fluid management strategies in patients with acute VOC.

This multi-center, open-label, non-inferiority RCT will enroll patients with SCD presenting with acute VOC. Participants will be randomized to either a restrictive or liberal intravenous fluid management protocol. Primary outcome is pain score reduction. Secondary outcomes include time to pain resolution, ED length of stay, hospital admission rate, cumulative opioid dose, adverse events (incidence of fluid overload, pulmonary congestion), acute chest syndrome, incidence of acute kidney injury, revisit rates within 72 hours of ED discharge, need for intensive care or high-dependency unit admission, need for additional interventions, and 28 days overall mortality. Data will be analyzed using intention-to-treat principles.

We hypothesize that a restrictive fluid strategy will achieve non-inferior pain control compared to a liberal strategy, while minimizing fluid-related complications. This study will provide evidence to inform clinical guidelines for fluid management in SCD patients experiencing VOCs.

Full description

This study is a prospective, non-inferiority, open-label, multicenter randomized-controlled trial (RCT) conducted in the emergency departments (EDs) of tertiary care hospitals in Saudi Arabia. The primary objective is to compare two fluid management strategies- restrictive (intervention) vs. liberal (control) in adult sickle cell disease (SCD) patients hospitalized for VOC. The study evaluates whether a restrictive fluid approach is non-inferior to a liberal strategy in terms of pain resolution, hospitalization duration, and other clinical outcomes.

Patients will be randomized upon ED admission, and their assigned fluid regimen will be administered within the first hour. Clinical teams will monitor outcomes throughout hospitalization or up to 28 days post-enrollment.

Study Population

1. Recruitment Screening: All patients admitted to the ED with VOC will be screened for eligibility.

   Consent Model: A priori informed written consent will be obtained from conscious, coherent patients or substitute decision-makers.

2. Inclusion Criteria Age >18 years with confirmed SCD diagnosis.

   Presenting with VOC requiring hospitalization.

   Willingness to participate and provide informed consent.

3. Exclusion Criteria Requiring specialized IVF management per physician discretion.

Cardiac/Renal Conditions:

Congestive heart failure (CHF) or symptomatic systolic heart failure.

Chronic kidney disease (CKD), acute kidney injury (AKI), or renal transplantation.

Hemodynamic Instability:

Shock (SBP <100 mmHg or MAP <65) with hypoperfusion signs.

Other Exclusions:

Known/suspected pregnancy.

Prior enrollment in this trial within the last 30 days.

Concurrent enrollment in another trial affecting fluid management.

Inability to obtain IV access.

Trial Intervention

1. Screening & Randomization Screening occurs upon ED admission; evaluations must precede randomization.

   A screening log will track eligible vs. randomized patients.

2. Informed Consent A-priori consent model used due to the conscious-coherent state of most SCD patients in VOC.

   Efforts will be made to obtain consent immediately from the patient or surrogate.

3. Intervention Arms A. Intervention (Restrictive)Keep-vein-open (KVO) rate only (minimal fluids to maintain IV patency). No additional IV fluids administered.

B. Control (Liberal) 20 mL/kg IV bolus (NS or LR over 1 hour) + maintenance fluids (1.5-2 mL/kg/day).

Initiation: Both regimens start within 1 hour of ED admission and continue until ED discharge.

Hospitalized Patients:

Pain scores (NPRS) recorded at 24 & 48 hours. Total fluid intake documented at hospital discharge.

Enrollment: 394 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Patients >18 years old with a confirmed diagnosis of SCD.
2. Presenting with a VOC.
3. Willingness to participate and provide informed consent.

Exclusion criteria

1. Patient requiring specialized IVF management as per the treating physician discretion.
2. Patients with congestive heart failure, and /or acute or chronic symptomatic systolic heart failure
3. Patients with a history of chronic kidney disease, acute kidney injury or renal transplantation
4. Patients with signs of shock (low SBP <100 or MAP < 65) and signs of hypo perfusion
5. Known or suspected pregnancy
6. Previously enrolled in this trial within the last 30 days
7. Enrolled in another trial study that interfered with fluid management
8. Unable to obtain IV access.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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394 participants in 2 patient groups

Restricted approach group

Experimental group

Description:

Patients in this arm will receive maintenance intravenous fluids at a keep-vein-open (KVO) rate and no extra intravenous fluids is administered

Treatment:

Drug: Sodium Chloride (NaCl) 0.9 %

Drug: Sodium Chloride (NaCl) 0.9 %

Liberal Approach Group

Active Comparator group

Description:

Patients will receive an IV bolus of 20 mL/kg of normal saline or lactated Ringer's over 1 hour, followed by maintenance fluids at 1.5-2 ml/kg times the calculated daily maintenance requirements

Treatment:

Drug: Sodium Chloride (NaCl) 0.9 %

Drug: Sodium Chloride (NaCl) 0.9 %