The Efficacy of Adjunctive Intravenous Ascorbic Acid on Blood Loss in Patients Receiving Intra-articular Tranexamic Acid for Total Knee Arthroplasty: Randomized Controlled Trial

Status

Active, not recruiting

Phases

Phase 4

Study type

Interventional

Source

TCTR

Registry ID

TCTR20251201004

Enrollment

Registered

2025-12-01

Start date

2025-12-01

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Patients diagnosed osteoarthritis undergoing primary unilateral total knee arthroplasty Osteoarthritis of Knee, Total Knee Arthroplasty, Ascorbic acid

Interventions

- First dose: 1 gram intravenously, administered 15-30 minutes before surgery - Second dose: 1 gram intravenously, administered after tourniquet release - Third dose: 1 gram intravenously, administer

Experimental Drug,Placebo Comparator Drug

Treatment Group (Ascorbic Acid),Control Group (Placebo)

Eligibility

Sex/Gender

All

Age

55 Years to 85 Years

Inclusion criteria

Inclusion criteria: 1. Patients diagnosed osteoarthritis undergoing primary unilateral total knee arthroplasty 2. Age 55 - 85 years 3. Able to provide written informed consent

Exclusion criteria

Exclusion criteria: 1. Preoperative hemoglobin < 10 g/dL 2. Coagulopathy or bleeding disorder (defined by laboratory results: INR > 1.5 or aPTT ratio > 1.5) 3. Known allergy to ascorbic acid or tranexamic acid 4. Contraindicating use of ascorbic acid - Diagnosed G6PD deficiency or sickle cell disease - Use of major interacting medications: - Warfarin within 7 days prior to surgery (diminish the activity of anticoagulant) - Receipt of chemotherapy drugs within the last 6 months prior to surgery 5. History of venous or arterial thromboembolic disease (DVT, PE, stroke, myocardial infarction) 6. Severe renal impairment (specifically: Creatinine Clearance < 45 mL/min) 7. Severe hepatic impairment (Child-Pugh C) 8. Substance abusers including drugs and alcohol 9. Participation in another interventional clinical trial

Design outcomes

Primary

Measure	Time frame
Total calculated blood loss (mL) at 72 hours after surgery using Hb balance method	—

Secondary

Measure	Time frame
Total calculated blood loss (mL) at 24, 48 hours after surgery using Hb balance method,Postoperative Hb level (g/dL) at 24, 48, 72 hours CBC,Hemoglobin drop (g/dL) at 24, 48, 72 hours CBC,Inflammatory marker at 24, 48, 72 hours CRP (mg/L), Fibrinogen (g/L) ,Blood transfusion rate (%) admission period rate,Operative time (minutes) Intraoperative period record,Pain scores at 24, 48, 72 hours (VAS, 0-10),Incidence of adverse events and complications admission period record	—

Measure

Time frame

Total calculated blood loss (mL) at 24, 48 hours after surgery using Hb balance method,Postoperative Hb level (g/dL) at 24, 48, 72 hours CBC,Hemoglobin drop (g/dL) at 24, 48, 72 hours CBC,Inflammatory marker at 24, 48, 72 hours CRP (mg/L), Fibrinogen (g/L) ,Blood transfusion rate (%) admission period rate,Operative time (minutes) Intraoperative period record,Pain scores at 24, 48, 72 hours (VAS, 0-10),Incidence of adverse events and complications admission period record

—

Countries

Thailand

Contacts

Public ContactNatthapat Niyomrattanakit

Srinagarind Hospital, Khon Kaen University

nattni@kku.ac.th0914360239

Outcome results

None listed

Source: TCTR (via WHO ICTRP) · Data processed: Aug 10, 2026