NCT07037485

The Predictive Value of Doppler Based Renal Ultrasound and Urinary Oxygen Tension for Prediction of Acute Kidney Injury After Open Heart Surgery

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 50 (estimated)
• Sponsor: Tanta University · Academic / Other
• Sex: All
• Age: 21 Years
• Healthy volunteers: Not accepted

Summary

This study aims to investigate the predictive value of Doppler-based renal ultrasound and urinary oxygen tension in the development of acute kidney injury after cardiac surgery.

Detailed description

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a complication following cardiac surgery occurring in 15-30% of patients. It is associated with increased morbidity and mortality as well as prolonged hospital stay and higher medical costs. The renal artery pulsatility index (RAPI), which is determined using Doppler measurements, has been reported to detect patients with a high risk of AKI. Additionally, the renal resistance index (RRI), measured by Doppler ultrasound, can accurately predict the occurrence of AKI. Urinary oxygen partial pressure in the bladder has been shown to decrease in the setting of sepsis, reduced renal blood flow, and decreased cardiac output.

Conditions

• Doppler-Based Renal Ultrasound
• Urinary Oxygen Tension
• Acute Kidney Injury
• Open Heart Surgery

Interventions

Type	Name	Description
OTHER	Renal resistive index	It will be measured with ultrasound-Doppler using an abdominal curvilinear probe ultrasonography by two independent, trained sonographers (who will not be involved in patient care). After visualizing the kidney in ultrasound mode and checking for renal abnormalities, an arcuate or inter-lobar artery will be localized, and three successive Doppler measurements at different positions in the kidney (high, middle, and low) will be performed. The average value for each kidney will be taken. The renal resistive index will be calculated as follows: (systolic peak flow velocity - diastolic minimum flow velocity)/systolic peak flow velocity
OTHER	Renal Artery Pulsatility Index	It will be measured using an abdominal curvilinear probe ultrasonography by two independent, trained sonographers (who will not be involved in patient care). After visualizing the kidney, the interlobular artery will be located using color Doppler mode, and the velocity of the interlobular arteries will be assessed in one or two kidneys. The Renal Artery Pulsatility Index (RAPI) will be calculated as follows: RAPI = \[(peak systolic velocity) - (end diastolic velocity)\] /average velocity
OTHER	Urinary oxygen tension (PUO2)	Urinary oxygen tension (PUO2) will be measured preoperatively (baseline), postoperatively just after intensive care unit admission, 12 hours after surgery, and then once daily for 7 days.

Timeline

• Start date: 2024-10-01
• Primary completion: 2026-09-01
• Completion: 2026-09-01
• First posted: 2025-06-25
• Last updated: 2025-06-25

Locations

1 site across 1 country: Egypt