Interest of Urinary Oxygen Partial Pressure (PO2u) in Predicting the Onset or Recovery of Acute Renal Failure During Shock States - OXYpi Study

Condition(s) studied

Investigational drug(s) / intervention(s)

Continuous measurement of uPO2 (both groups): uPO2 is collected continuously for the first 5 days of admission or until discharge from intensive care or removal of the urinary catheter.

Study summary

Shock state is defined as an acute, life-threatening, circulatory failure with impaired tissue oxygenation (or tissue hypoxia). The cause of the shock state can be septic, anaphylactic, hypovolemic or cardiogenic. Its management is based on etiological treatment and replacement of organ failures. Acute kidney injury (AKI) may be lead by renal hypoxia. Acute kidney injury is frequent in patients admitted to intensive care unit (ICU) and associated with an increased mortality. Serum creatinine is the reference biological marker in the diagnosis of Acute kidney injury. However, its use is limited by a delayed increase in plasma creatinine level in relation to the causal renal agression, at a time when renal tissue damage may already be established. Thus, the identification of a biological marker making it possible to estimate renal hypoxia continuously during a shock could allow us to identify early a situation at risk of evolving into Acute kidney injury.

The renal medulla is vulnerable to tissue hypoxia with a risk of acute tubular necrosis. As in situ measurement of mPO2 is not possible in current practice in humans, several studies have shown a positive correlation between variations in mPO2/uPO2 and occurence of Acute kidney injury. In humans, studies have shown a significant association between the reduction in uPO2 in cardiac surgeries and the occurrence of postoperative Acute kidney injury. The aim of the study is to describe the association between uPO2 values and the onset of Acute kidney injury and/or the ocurrence of early recovery of renal function after Acute kidney injury. Any patient in shock (group A) or without shock and requiring urinary catheterization as part of treatment (group B) admitted to the Medical-Intensive Care Unit of Angers University Hospital is eligible for inclusion. After inclusion, a continuous uPO2 measuring probe is introduced with the placement of the urinary probe. uPO2 is collected continuously for the first 5 days of admission or until discharge from intensive care or removal of the urinary catheter. uPO2 is also measured by a gasometry on a urine sample on a multi-daily basis. Serum creatinine is collected every 12 hours (twice a day) and diuresis every two hours for 5 days.

Eligibility

Primary outcome measure(s)

• A - For patients without acute kidney injury at inclusion, the occurence of acute kidney injury and its severity according to the KDIGO criteria — During the first 5 days after inclusion.
  A KDIGO Criteria: Increase in serum creatinine ≥ 26.5 µmol/L during the 48 hours following inclusion Or an increase of ≥ 1.5 fold the admission serum creatinine during the first 5 days Or Diuresis \< 0.5 mL/kg/h for 6 hours during the first 5 days
• B - For patients with acute kidney injury occurring during the first 3 days following inclusion, early recovery is defined by the return to pre-shock renal function 48 hours from the start of acute kidney injury — During the first 5 days after inclusion.
  A KDIGO Criteria: Increase in serum creatinine ≥ 26.5 µmol/L during the 48 hours following inclusion Or an increase of ≥ 1.5 fold the admission serum creatinine during the first 5 days Or Diuresis \< 0.5 mL/kg/h for 6 hours during the first 5 days
• C - For patients with acute kidney injury occurring at inclusion, describe the evolution of PO2u values in patients with worsening renal function — During the first 5 days after inclusion.
  A KDIGO Criteria: Increase in serum creatinine ≥ 26.5 µmol/L during the 48 hours following inclusion Or an increase of ≥ 1.5 fold the admission serum creatinine during the first 5 days Or Diuresis \< 0.5 mL/kg/h for 6 hours during the first 5 days

Trial sites (2)

More University Hospital, Angers trials in France